Sexy Bolt-ons - Throttle Body Fuel injection

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Sexy Bolt-ons - Throttle Body Fuel injection

Post by Rizz280s » Fri 04 Jan, 2019 11:15 pm

Hey all,

While thinking about how to transition my old girl to a daily driver I have weighed up a heap of different options from engine swaps to electric motors to fuel injection. My main concerns are reliability across different weather, gains of power/economy and complexity/cost for setup.
The current winning option at the moment is fuel injection, namely throttle-body fuel injection.

There's loads of this stuff made for the American hot-rodder market already, but I am keen to hear what people here have to say. I have a love-hate relationship with my carby - as I know many of you do too - but ultimately, it's inefficient and can't adjust on-the-go to changing weather conditions too well.
I have read a lot on here about people's experience with MegaSquirt, but not about going from a carburetted engine to anything that can be controlled by a megasquirt ECU for example.
So, does anybody have any experience with going from carby to factory injection, or carby to throttle-body EFI?

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by cuisses » Sat 05 Jan, 2019 11:08 am

Rizz280s wrote:
Fri 04 Jan, 2019 11:15 pm
My main concerns are reliability across different weather
Isn't it always sunny and 27 C in Perth? If a carbie cannot cope with Perth, heaven help it in a place that actually has weather. :laughing6:
David Williams

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by Rizz280s » Sat 05 Jan, 2019 2:18 pm

The last 2 years have been a bit colder, wetter and more miserable actually!
She struggles to get going in the wet (though it might be an electrical problem) - but really I am hoping for an improvement in both economy and power

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by CraigB » Sun 06 Jan, 2019 12:09 am

I like the line of thought. The most common questions/actions you see are people wanting to change power plants and I wonder if they have done their sums because that sort of thing usually costs a lot more than what you think - different if doing it just because you want to and don't care about money. But i often think down the track about keeping things going and what might help something older be a 'daily'. I am just in the process of getting rid of our 'disposable' daily and going back to something that can be economically repaired. Depends where you are and how fast you need to go, but for me a properly running 280s is fine for go but economy is where a lot of these cars fall behind modern stuff ( but not all of them - my 96 defender is a lot more economical than a newish diesel Hilux doing the same job - don't believe manufacturers economy claims). Because it does its lion's share of the miles, have always tried to have one reliable, economical car but I also hate depreciation. I was thinking along the lines of a used Prius and convert to a plug in, but the reality of potential battery replacement cost, extra battery cost etc etc, what electronic jiggery can still go wrong and what it will be worth after all the new electric cars start to flood the market in a few years time and I just think it is too soon and certainly doesn't make economic sense - we don't do a heap of miles anyway.

So that's a long background to my thoughts. I ran a manual 108 250s as a daily for a long time on LPG - it was a good conversion by a guy who knew his stuff and had good power and economy. I also had a W116 280s that I got converted to straight gas for less money than it was to try and reliably fix my 'Solex' problems. I wasn't sure what to expect, I just wanted it to run right, but it actually put out good power on the dyno compared to standard and a lot more torque and at the time LPG was a lot cheaper. But hearing other stories and driving other cars, you can have vastly different results and not all lpg conversions are equal. I don't know what the rebate situation is now but the price of gas alone would make it harder to make the numbers work and if you really need more power then you are probably at best going to maintain it.
Rizz280s wrote:
Fri 04 Jan, 2019 11:15 pm
My main concerns are reliability across different weather, gains of power/economy and complexity/cost for setup
Just checking your list..... your 108 was designed for a cold, wet climate and I have never had any trouble with any of mine starting, so something is wrong , but I don't think that is the point - and all have been reliable. Not a light car so I am not sure how much you could hope for with economy.

If it was a carby M110, you can just change to an injected head to go down an injected route. M130 is a different shape block and head and don't know what would be involved in fitting injectors. The only way would be getting an entire engine to go to the factory set up you are asking about. There is a bit to go wrong in the set up too, so i guess a running but rusty 280SE would be what you would be looking for as a donor. And I am guessing that is all getting a bit complex. Finally getting to the title - I don't know about these throttle body set ups but you will need to think about manifolds to make that all work. I don't know if an injection manifold will bolt straight up to your head, possibly would, and not sure the impact but they have quite long runners. And agreed I haven't heard of anyone going megasquirt on the SOHC 6's.

Not sure if any of that helps but its my thoughts - have you looked on Benzworld? Having a strong US focus and their hotrod enthusiasm, might be someone there that has gone down that road.

And have you looked into the weber conversion? People seem to love them, but not heard dyno figures if there is power increase and/or economy increase. No doubt the easiest way to get easier starting and a matter of if it meets your other aims.
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by Rizz280s » Sun 06 Jan, 2019 2:04 am

Hi Craig,

Thanks for your thoughts. The car has a holley 'conversion' already - a home-job intake manifold with a 2-barrel Holley carb slapped on top. It doesn't give me much grief, except for when the humidity rises. I still can't figure that one out, as it fires up first time when the temp is anywhere near 25C.

I've always had the 'disposable daily' alongside something more fun and now I am thinking of getting a motorbike as my economical daily driver, but that will also take a bit more planning and commitment on my part yet. I actually reckon an old hybrid could be a great option very soon - as hybrid batteries start to conk out, while battery prices are falling, you could get a cheap hybrid and, if you got around to fitting a newer replacement battery, it would probably extend the range beyond factory spec. Who knows how electric cars are going to shake things up though.
I was actually struggling to find flat-head screw drivers and drill bits in Bunnings today - old technology can make things difficult.

The LPG option is an intriguing one to me. I've only recently learned that factory LPG (in Falcons anyway) is basically just a carburettor system. Very basic. I have owned several LPG cars now though (including my current run around) and I am noticing that prices for LPG are going up to a point where it's almost not worth having anymore and it's becoming harder to find petrol stations selling LPG! The complete loss of boot space is the final straw that kills that idea for me.

I love the idea of 'making' a hybrid drivetrain (either with hub motors like this: https://www.youtube.com/watch?v=iQ4lTPVR3qc
or with a belt-assist, purely for torque like this: https://www.youtube.com/watch?v=4-Vck6oCi3A&t=80s
You could get the instant torque of an electric motor (taking some of the demand off the engine around town), while getting the range from petrol. But that's all a bit of a pipedream for now...

Back to bolt-ons, I've been seeing a load of videos about these 'FiTech' systems lately, that are essentially adaptive throttlebody fuel injection and supposedly give a boost for reliability and economy. Basically they don't have a traditional ECU (where you would have to tune the thing on a dyno and write a new fuel/ignition map for the particular vehicle), but rather just a small computer that adjusts the glorified carby on the go by taking data from a plug-in O2 sensor and adjusting the mix to ensure you get a clean burn. I searched Ozbenz and found a single post about them, but I would not be surprised if we begin to see more here. $1700 for the base model on eBay doesnt sound bad, but I want to hear a second opinion first.

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by drew56cus » Sun 06 Jan, 2019 8:27 am

Hi,
I am not really that clued up, JoeB is clever with things like this so hopefully he chimes in, but here are some random notes i have in my head from reading things over the years:
- I remember someone on Benzworld had gone with megasquirt, but it really didn't do much for economy. It would take years and years to pay for the changeover cost due to fuel savings
- you would want to use the intake with the long runners of the FI motor rather than the carb intake. Something to do with puddling of fuel in the short one.
- I ran a 220S and 280S in Brisbane for many years and had no problems. I run a '76 Escort now with a carb and again, it is no big deal in winter. Just get them set up right.

Cheers,
Drew
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by AMG » Sun 06 Jan, 2019 10:41 am

OK, I'll chime in, but I guess what I have to say won't sit well with some.

You have 3 options.

1. return the carb to the original setup, with a properly overhauled stock carb, and tune it on a rolling road.

2. get rid of the holley, search for Weber DCOE carbs and manifold ($$$$) if you find s/h in europe, then buy it. then get the carbs properly cleaned here locally (AKSES in brisbane was my old go-to a couple of decades ago) You can DIY a weber overhaul. they are not rocket science, however you do need some tools and you will eventually buy them regardless. so do it upfront and teach yourself the mysteries of Weber. hint... there aren't any. All you neeed to know is that emulsion tubes and air correction jet nomenclature changed and you need to know which type you are using.

3. EFI conversion.
There are a few ways to go about it. The one way you don't, is by using a holley efi kit or some equally atrocious thottlebody injection system. Theya re a waste of time, deliver no performance over a carb, and use just as much fuel, tempremental idle and heat soak issues just like carbs. WOFTAM.

So, you can choose a factory injection setup - which you'll need to overhaul at $$$$ (or possibly $$$$$ for a MFIS m100) or you can go in for some fabrication / adaptation.

Standalone EFI systems like Autronic, adaptronic, motec and haltech among others are far more robust and supported than megasquirt DIY.
Unless you want to devalue your car for the next owner, stick with a known reputable aftermarket brand with a proper wiring harness and use only new components where required.

You can adapt late model MB parts, like MAF's or fly by wire accelerator pedal / throttle body afm. OR you can go the aftermarket route. Choice is infinite and yours alone.
If you know little, then do not stuff around yourself. It will cost you twice as much as having a pro do it for you. If you do know what youre doing and have the tooling necessary to do it properly, then DIY is a cost saving from the labour perspective only.


At minimum you need: an airflow meter / map sensor, a throttle position sensor, coolant temp sensor, a crank trigger, a cam trigger, a wideband O2 sensor, an adjustable fuel pressure regulator, and the normal conventional parts for any modern EFI vehicle, such as fuel pump(s) filters, return lines, injectors, ignition coils, plug leads etc.
You may also choose to use a flex-fuel sensor, and some other sensors (k-type thermocouple for exhaust, an oil temp sensor, and a gear position sender-switch)

By the time you work all this out, I'm going to roughly estimate it's somewhere in the vicinity of about $5k in parts, including the ECU and harness.

You will need tools to crimp injector plugs and such, and the manual that came with your ECU to tell you how to wire it all up.

You're still going to need a professional with a dyno to tune the ecu properly - but this is moreso the case with motec / haltech / adaptronic which have a high resolution map setting and this cannot be done without a dyno. In some cases you have to pay to unlock a feature on the ecu to allow this (motec is an example of pay for everything) Autronic SM4 has a very high resolution automatic tune in semi-closed loop function or open loop if you have a proper high res wideband O2 (NTK) super fast probe.

O2 sensors are literally the difference between a finely tuned engine and a hand grenade. A cheap nasty O2 sensor will not reward you with anything but trouble. At the other end of the scale, a true NTK probe will hurt you to the tune of $1K, and it is not recommended you use it for daily driving, simply because it's so expensive and O2 sensors do get clogged with crap, and will do so quickly on a poorly mapped engine being tuned for the first time.

If you wonder why dyno tuners take all day, this is one reason. start-up, quick run, get data, shutdown. Lather, rinse, repeat. Only when the map is better than 80% will they do a properly loaded run. Then they will go back and adjust values up and down the fuel and ignition maps. They will do this for full throttle, part throttle and idle, in each gear - IF they know what they are doing. There are plenty of tuners out there who think they know what they are doing because they have a laptop and a dyno and an R34 skyline or an STi wrx in their workshop driveway.

Avoid those places if possible.

You want someone who knows your ECU AND your engine. This will be difficult to find, but ultimately, it will fall on you to trust someone who understands older cars, and you may also find they are reluctant to tune, unless you can validate the engines internal condition - compression, mileage, recent rebuild etc. There are a lot of places who will simply not touch your car, because on a dyno, things will and do FAIL. And unless your dyno operator is a complete kook, the problem actually remains with you.

Plenty of cars have blown up on dynos, because an owner was looking for a magic number.

Leave your ego at home when you go to a dyno. Talk to reputable workshops and ask them who they know and then go see them to decide for yourself.

Mate of mine just lost a $20K 13b turbo rotary to an incompetent dyno operator, who was recommended by his engine builder. Another engine was built at no cost - because the data from the dyno run showed the operator made a fuelling mistake.

both reputable guys, both working together and both understand that the customer wasn't going to pay until the engine was in his car.

And that's another thing.... an engine dyno is always a much better way of doing this than a rolling road. But they are few and far between here in oz. you will need to visit a racing engine workshop.

could go on and on, probably not worth it. Hopefully You've understood that the cheapest and best option is to return it to original with a properly rebuilt carb. failing that, go for webers. both options are cheaper than standalone EFI and throttlebody efi is a complete waste of f-ing time and money.
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by VFRBoy » Sun 06 Jan, 2019 11:10 am

What a great thread!

These thoughts have been back of mind for a while here also, but tending towards the turbo route. To my mind the engine is well suited - strong bottom end, relax the compression a little and add a modest amount of boost.

Has this been done?

I have a 1966 250S with floor shift manual. The Zenith carbies are well sorted but mileage could be better. 18lt/100km around town, and just got 13 on a 300km trip to the coast.

The diff ratio could be taller, guessing that a USA sourced 4.5 transplant would be best, even without the turbo idea.
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by CraigB » Sun 06 Jan, 2019 2:04 pm

It is an interesting read. Confirming and summarising thoughts in my head - not all well described so far - as great as it would be to have the 108 looks and the ultimate power/economy for a daily, there are going to be limits on what can actually be achieved and just like race cars, every extra HP gets more and more expensive proportionately. I have a feeling the 'sweetspot' for the cheapest/most bang for buck improvement to get it to start well, reliability, give some power and economy increases and a known cost of around $1k from all the people who have done the redline Weber kit - this I reckon is that sweetspot. I also get that feeling when someone with the sort of knowledge and experience of Ron in qld have done this to cars more than once and raved about it. Not saying Joe doesn't have great knowledge and experience but I don't think you have played directly with 108's..... be sensitive Joe if you want to explain why you haven't played with 108's!

And Joe, is DCOE a typo? Imagine you mean the redline downdraught kit - DGAV i think it is. I've seen 3 x DCOE hanging off the side of a M110... but not great economy!

You could get Zeniths and work on them and put it back to original but I suspect time and money involved, new Webers will turn out cheaper. I have had a good run (touch wood) with Zeniths, but they are old and once shafts start wearing, bodies warping etc the the time and/or money starts clocking up. Also the reference to using rolling road - my understanding is that those redline kits are already jetted perfectly for the car and its just a matter of minor fine tuning to get it right. But worth checking this with those that have done it and also what they have got with power and economy increases - preferably numbers and not just 'seat of pants'.

But not as much fun as all these other thoughts are to discuss! A lot of what i read in to most of these suggestions is time. If I only had one car I was playing with and interested in then it would be different but I am just spread too thin with current projects i really want to do that are straight, not complex resto things. Still, I'm interested where others have done legwork - have you read Alastair Dow's description of his M116 megasquirt conversion. You get some idea of how much time he put into that and his testing and also the level of increases.
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by Rizz280s » Mon 07 Jan, 2019 12:30 am

Wow, this is turning into a great thread! It seems these kinds of thoughts are swirling around in many of our minds.

VFRboy - I considered turbo as well, but I think to turbo a carb'd engine of any sort is a very complex art, and one that puts your engine at much greater risk of mechanical failure (with the increased chance for knock if for example timing isnt set properly). That's just not a good road to go down in my mind, but I'm happy for someone else to do the experimenting haha.

AMG - thanks for the write-up. I think you're absolutely on the money. (1) Going back to stock doesn't particularly excite me - though carbies designed for this car should really work better than the low-end American carby on dodgy home-made manifold setup I have. It's an option.
(2) Holley and Weber carburettors are the same as each other in my mind, but that's probably completely uneducated statement. What are the benefits of a Weber?
(3) TBI EFI - I came to the same conclusions about these setups after exhaustive searching last night: There's rave reviews about the Holley Sniper, this FiTech thing and others, but ultimately they are glorified carbs. When trying to find any actual benefits to power or economy, I just couldn't find any. They are just carburettors which adjust the idle to match a fuel-air ratio, as detected by an inbuilt MAF and feedback from an O2 sensor - ultimately not any more precise or economical than a well-tuned carby. The fuel is not under high pressure, so fuel intake really isn't any more controlled. There are seeming benefits to starting and idle of TBI EFI setups, and the FiTech supposedly controls ignition timing too - so that might have some benefits to either power or economy, but I could not find any hard data and a system that relies on constant feedback could not be as responsive as a system running on a properly mapped ECU.
The fabrication-of-injection route has gotten my imagination going, but who am I kidding - I am still a time-poor university student on bottom dollar. The quoted power output figure on wikipedia for the 280S (100kw) is better than most other carburetted 2.8L engine vehicles of the same era and up to about 1985, and the car gets off the mark fairly respectably, so I guess I shouldn't really complain. It's shifting almost 2 tonnes of mild steel and leather down the road after all!

As you go on to say - the cost-benefit ratio starts to wear thin when you look at the actual cost of all components and labour involved in going to true fuel injection, at which point I think, 'gee, I can get a salvage 2010 Falcon for $1800 with a 4L engine putting out 195kw, 391nm of torque at almost double the fuel efficiency and swap out the engine, exhaust and trans' and consider that a more economical route. But then, its still all time and money. I'd still have to fit it properly (hours of fiddling, probably fab new mounts, possible changes to trans tunnel, re-wire, flash the ECU etc), still have to get it approved by an engineer, approved by department of transport and all that jazz to essentially have a heavy Falcon with no aircon or safety gear.
Good tips on the dyno though - Youtube had me believe there's dynos all over the place and that a tune takes a few hours max.

Drew and Craig - I reckon you're both right too. It's the old law of diminishing returns. Every extra bit of economy/power is going to get more expensive and time-consuming and ultimately, it's probably worth my time to just get the carbs I've got running right.
The car does run well and power and economy actually aren't too horrific. The cheapest solutions would be to improve power-to-weight ratio (by stripping out some of the soul of the car), throw in a gearbox with overdrive (another potentially expensive pain in the ass project) or just get the car up to scratch and enjoy her how she is. Who knows - a year or two from now I might not even be in the same country and it might not make sense to take the old girl with me. It's all fun to think about though!

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by CraigB » Mon 07 Jan, 2019 8:39 pm

That all sounds good. I think the only question i can answer in there is the one about "what are the benefits of a Weber" - I can't vouch for all Holley carbs - I had one on my M110 W116 and it ran horrible - but very little investigation and it was clear it was totally the wrong Holley for my car - someone probably got a 'free' carb off a mate and thought "I can make that fit" - hey its a carb that mixes a bit of fuel and air - all the same aren't they and this one is free!...... then spend god knows how many hours making it fit and trying to tune it and then ending up with shocking fuel economy and power.... like it was when i got it. I guess that's why ages ago when you said about your carb and manifold I think i was picturing something like my situation and I think I mentioned that.

So the point I was making is it's not about Holley or Weber or even Zenith who no doubt have all made at least some good carbs over the years. My point is that going on averages of comments here and OS forums (and there are exceptions of course), there are lots and lots of people that have trouble with old and possibly worn out Zeniths. I reckon if you could buy brand new W108 Zeniths at a reasonable price, that would be a great solution. But you can't. Then on averages of comments there are lots of people who have fitted those redline Weber kits (not any old Weber a mate gave them but a brand new specific Weber that has been set up, jetted and tuned specifically to go on a W108 and with the same features that replicate those of the original zenith with the choke set up etc. - what i have read is you basically bolt them on and go. Without looking it up I think it is a DGAV and lots of cars used that carb i think, and you could go to a wrecking yard and find some no doubt and then look for bits to make up linkages and then get it all on there and then find a good place with a dyno and good range of jets and emulsions tubes or whatever and x hours of dyno time down the track you might be able to replicate what the company would have done to derive the set up so they could sell lots of these kits! So that's why I was suggesting it as a good option - but hoping someone who has done it chimes in with some data on economy ... and power would be good if someone put one on a dyno. So its $1000ish but that's it compared to all the other discussion of the costly set up stuff. But i haven't personally done it and this is just the vibe I got out of other comments from people...... hope that makes sense.
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by Bartman4800 » Tue 08 Jan, 2019 12:54 pm

Craig, It's a DGEV that is best suited (or rather a pair of)

The DGAV opens both throttles at the same time (better for track use), the DGEV is a register carb (first the one throttle, then the 2nd opens progressively). The E stands for electric choke, which is what you need.

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by CraigB » Tue 08 Jan, 2019 1:24 pm

Thanks Bart - I was just being lazy not looking it up.... but yes, what you have described is a replication of what the original Zenith had - but its new and without a reputation for warpage etc.
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by AMG » Fri 11 Jan, 2019 9:29 am

Craig,

I was talking DCOE, not DGV DGAV or DGEV, all of which I have transplanted on jap 4 & 6 cyl cars, holdens, fords and valiants (yes downdrafts on a crappy standard 245 hemi - why :wall: ). The weber DG downdrafts are really a compromised design, and further to that, you still have a 90 degree bend for the mixture to negoatiate into a standard manifold with an adapter plate. Not a fan. It is the cheapest carb-swap method when your zeniths are leaking like sieves and the entire body needs machining (happens often).

Cheap does not net you huge differences for your outlay. Counter that with "Webers are not cheap" - what I mean is 'path of least resistance'

Sure, you will improve over standard if your original setup is horribly out of tune or completely fkd. But so will anything replacement in that situation.

Looking at it with a degree of dissociative logic, I cannot fathom why anyone would 'spend' unless they had 2 absolutes written in stone - those would be:
1. I want a relatively straightforward bolt-on solution with minimal work
2. I am not flush with enough cash to do a proper induction setup

Now that's not being mean about it, that is just straightforward logic. Yes these cars are old, parts are getting scarce, whatever is available IS going to be expensive, so a DGV type downdraft will be cheaper and easier than rebuilding zeniths, and deliver an improvement - from the sheer fact that 2 new webers are exactly that - brand new. So unless they are completely mis-configured (ordered incorrect base model) they will be almost a 100% bolt-on swap, with maybe an air correction jet or emulsion tube swap, or both, and worst case a main jet or idle jet size change.... but that would go back to my previous statement about ordering the wrong carb... because Webers are orderable in configurations that are more or less spot-on for nearly every carburetted vehicle on the planet. Whether it's a 1600cc fiat twincam or a beetle, an old 2.7 porker flat 6 with ID3c's or 4x 48 IDA's on a redline for a 383 stroker holden 308. They are literally catalogue-part number orderable and have been for over 25 years.

The absolute obvious "improvement" on an m130, m180 m110, m127 or m129 is to use the factory fuel injection induction setup - be that just intake manifold or the intake and head where required.

I'll throw a spanner in the works and say this:

It would be cheaper to take a w124 300e donor with a 3.0 m103 and 722.3 transmission, remove the CIS-E harness carefully from the engine bay, along with the fuel pump relay, OVP and EZL, and drop the whole lot into the 108, with some engine mount adapters, and be done with it.

not only would the fuel economy improvement be out of sight, the motor would be the strongest and cheapest thing you could shove in there, (short of an m117 v8 for the torque)

Not a purist car then though, and I'm willing to bet you could source an entire w124 sedan in good condition with a good engine and trans for less than the cost of two DGEV's and adapter plates and a dyno tune. - it would be fuel injected, quiet, reliable, low cost maintenance, go forever if looked after and deliver a truckload more power than the original engine... and a better transmission to boot.

bit sideways with the discussion, but often the seeds are already planted when someone starts looking for alternatives to a straight-up overhaul of an existing problematic component.... and if you are looking for alternatives, then there are quite a few factory ones. even a 2.3L m102 or an M111 would be an improvement (and with a manual box, would be awesome in a 108)

Then there's the dream-team combos - m117.968, OM606, M113k, M104+Garrett... They have all been done in 108's and obviously there are a lot of other upgrades required with a huge power difference, but initial outlay for a used engine may not really be all that different from a pair of new Webers and adapter plates... The issue is the associated cost, time and labour that comes with an engine swap, versus a bolt-on upgrade....

really that is the entire crux of the discussion.... rebuild stock, buy bolt-on improvement or go all-out.

Far too many permutations and combinations to examine each in detail, and perhaps that is really the problem being faced... when there are too many options available, one can easily get caught out if the 'original' decision is not adhered to... people do change their minds, and often too.

I know someone nearby who is going through this right now with a 190e project :laughing6: :laughing6: :occasion5: Oh and another mate down the road with a 124 coupe which is slowly evolving in a different morphology each week. I'm not sure how either will finally end up, but I have my hunch that both gentlemen will only be satisfied with the original outcome for a very short period before revisiting their projects and making some alterations.

We ALL do this when we start changing things from standard. It's a disease that permeates your brain, leaving it addled. Researching the subject of choice only leads to excessive accumulation of knowledge on subjects closely associated with the actual task, most of which will not ever be used - and even if it is, subsequently becomes forgotten, until something else goes wrong - and you go back, re-read and remember... then the Homer Simpson moment occurs.

Regardless, I still stand by my original statement and advise against any standalone throttlebody injection setup design like holley use. Individual runner intake setups using Weber-style EFI throttle bodies are okay, but are still not as efficient as a true port-injection (like m103/m117 for example) type setup. You can adapt those CIS injectors for EFI with grommets and do a standalone as easy as you can do a carb swap, and the outlay is about the same, but there are costs involved with additional tuning on the rolling road or engine dyno.

If you had an MFIS or Djet induction setup already, then a modern standalone EFI conversion is a no-brainer. If you have carbs, then the dual-inline single plane downdraft manifold with 2 DGEV Webers and adapters is the most straightforward and least complicated swap.
Get it tuned properly by someone who can dyno the vehicle and has a selection of Weber air correction jets, emulsion tubes and main jets. measure AFR's under full throttle and at idle, as well as part throttle at cruising RPM, where the engine spends most of its time.

Just bolting these things on will only get you halfway there. They absolutely must be tuned properly by someone who actually knows how to tune webers... otherwise you're wasting your time and money.
Current:
1987 560SL 4sp. auto Signalrot "Stella"
1987 190E 2.3-16 5sp. man. Blauschwarz "Hermann"
1992 300CE-24 6sp. man. Perlblau / Iceblau "Gretel"
1992 Range Rover Classic 4sp auto Ardennes Green "Oswald"
2012 E63 AMG Speedshift MCT Diamantweiß "Klaus"
Previous:
1986 560SEL Anthracitgrau "Schultz" - In Mercedes Heaven
1987 190E 2.6 4sp. auto Signalrot "Sabine" - which now resides/owns Andrew M's Garage
1972 350SLC Astralsilber "Lurch" - now in the loving care of Craig B
1989 2.5-16 Blauschwarz 4sp. auto (parted) formerly owned by Derek/Hasan.
2012 Renault Sport Megane RS265 Trophy 8:08 6 sp. man. Liquid Yellow "Jean Rédélé"

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VFRBoy
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by VFRBoy » Fri 11 Jan, 2019 12:10 pm

^^ Amen.

FWIW Wilson Carburettors in Airport West had a look at my Zeniths and quoted $900 to rebuild them (both). They're still running fine, just a bit rich, and a little temperamental on the auto-choke sometimes, but it's good to know the option is there should I need it. BTW they have the cleanest, neatest workshop I have ever encountered, and were a pleasure to chat with.

On the engine swap the M103 path is interesting - has anyone direct knowledge of this being done? OM606 most desirable but $$$, yes?
1966 W108 250S
4-speed floorshift

Carn the Dees...

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by CraigB » Fri 11 Jan, 2019 8:32 pm

I had to google the kits to check - I though David Knight bolted them on his 220 and jetting etc was bang on - but then i see the same kit is for 280 and it doesnt' say "tell us what engine it is" - so would appear maybe you do need to do tuning. Still, there info would appear to suggest they have done work on jetting:

The Weber conversions by Redline are unique in many ways:

Redline was the first and is still the best conversion available.
Proprietary changes to the jetting allow for flawless performance.
Tuning and jetting from the leader in Weber conversions.
Expert phone support from an experienced sales staff.
Toll free customer support phone line - real people with real answers.
Factory Direct Pricing and Product Support.
Largest selection of Weber Carbs and parts
Same or Next Day Shipping on virtually every order.
We sell only GENUINE EUROPEAN WEBER carbs - no imitations.
Beware of Chinese made and "NorthAmerican Webers" -they may look the same - but they are not the original Weber carb.
The Redline kits contain the Genuine Weber from Europe.

But my main point with all that was quantifying just how much time is involved in doing stuff like engine swaps and if you can buy something that will save hours of dyno time to get it all correct. If the company did that first, then it should be pretty close and that can translate to saving money.

But if your having fun the time doesn't matter.

And just on the manual injection system set up, the block is different too - ie. just cant change head/manifold.

but interesting discussion.... bottom line, quick won't probably produce that much difference and if you want to get major improvements it will be lots of work.
Craig Baulderstone
280s's
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by Rizz280s » Thu 17 Jan, 2019 11:51 pm

Another little problem has sprung up that has demanded my attention, so the idea of squeezing a few more horses out is on the back-burner.
That said, I've been getting really hung-up on the idea of hybrids - where I could keep the existing engine and just give it a bit of help to get up to speed.
This might be a bit boring (or distasteful) for you all but here's a bit of a summary of my research over the past week or so on hybrids and my thoughts on the practicality of them. There's pretty much 3 types of hybrids on the market.

1. Belt-assist mild hybrid. These are pretty uncommon now and were a way to get a tiny bit more fuel economy out of a car, but featured in a few GM cars. The idea is that you mount an electric motor straight to the crank by a pulley in place of an alternator. In this way it can act as an alternator and a starter, using a serpentine belt - Belt Alternator Starter (GM BAS). They improve fuel economy (supposedly up to 20% on early models) by shutting off the engine while you're idling and by providing some force to the crank, thus taking the load off the engine, which improves fuel economy as well.

2. Integrated Motor Starter. This is basically the same as (1) except the motor is mounted between the engine and the transmission, completely replacing the starter motor and flywheel. A few early honda hybrids had these and they provide benefits in much the same way as the belt-assist hybrids - shutting off engine and quickly restarting at the lights, assisting under load. They have the advantage of not putting their load on the crank and having a more direct power coupling than a potentially slippery belt.

3. Toyota style electric transaxle. These are what you find in Prius and Camry hybrids and at first I was completely overwhelmed by them, but Weber State University have some great Youtube https://www.youtube.com/watch?v=ZmHpSyTsfm0 videos showing how they work (truly giving me a massive appreciation for toyota engineering!). The earlier style have two electric motors in series, coupled to a small (1.3L) super-efficient Atkinson cycle engine by a planetary gear set. The motors are different sizes - a small one to act mainly as a starter motor and alternator, and the other to act as a prime mover and to provide heavier regenerative breaking. The interplay between the engine and two motors is controlled so that everything is contributing to the output shaft when you need to go and only the electric motor is contributing when you're put-putting around. Amazing engineering - and much improved in the later parallel design. The gearing and control means you get the most efficient use of energy from both the (relatively tiny) motors and the engine - just brilliant. The newer parallel type electric transaxle is able to act as a CVT, without having any of the wussy belts and couplings that I thought all CVTs had.

ANYWAY. Could you simply 'bolt-on' one of these systems and go? Complexity of controlling any of these systems is pretty much the big issue here, but it is not impossible! All of these systems provide braking assist, give a nice instant torque boost and only need a relatively small battery pack (1-1.5kwh vs Tesla's 50kwh pack). Chucking in a prius transaxle would be a feat of computer and electrical engineering that could consume the rest of my life, so that's not really practical. The Honda system might require some serious modifications and only provides a modest increase to power and torque, but doesn't seem impossible either. The easiest option by far is the belt approach. To find a nice, strong, high-revving electric motor, a kWh of Li-ion batteries, a serpentine belt and mount couldnt be too expensive or technical either - to earn a respectable time off the mark and a bit of relief at the petrol station. I have no doubt that (first) companies will start up to offer exactly this sort of conversion and (then) bolt-on kits will arrive on the market shortly after.

This is my kind of procrastination! Just a bit of food for thought. Sorry for the essay!
Rizz

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by CraigB » Tue 22 Jan, 2019 9:42 pm

A combined generator/starter in the 1920's was called a 'Dynastart'. But will a motor automatically generate if spun or would you need to do something to it?
Craig Baulderstone
280s's
280SE3.5
280SL Ruby
300TE Otto
350SL Gloria
350SLC Lurch
450SEL Boris
500SEC's...including Syd
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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by Rizz280s » Mon 28 Jan, 2019 1:24 pm

Wow, I had never heard of a Dynastart before, but that's basically the idea. For a motor to act as a generator, it needs to have some permanent magnets. As long as there are a set of permanent magnets and a coil, you can produce a current. Different magnet types have different 'power densities' and the use of high magnetic 'power-to-weight ratio' neodymium magnets is a big factor in why electric motors are compact and powerful enough to powering cars. And that's about where my understanding of electric motors ends!

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Re: Sexy Bolt-ons - Throttle Body Fuel injection

Post by ben108 » Sat 02 Feb, 2019 6:22 am

I'm actually a fan of TBI.
You can use a throttle body, wiring harness and ECM from a US GM TBI car/truck with a bit of work.
I have done a couple of conversions from carbs like this and it can be very inexpensive if you know what you are doing.
Modifying the donor dissy, or your original to accept the donor pickup/module is the trickiest part.
They run geeat and use less fuel because they run closed loop with an o2 sensor.
The GM ECMs can be modded for real time tuning too.
W108 3.5
W211 E55 AMG

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