4.5 V8 into W111

[SwissCheese]

Hello
I want an M117 4.5. I have an r107 v8 manual bell housing. I have a 4-speed manual transmission in my W111. Combine all of this and you get a 200hp 4-speed fintail

Those are my plans, the m117 will fit into the fintail without any modification, I think just different engine mounts. Does anyone know if I have to lengthen/ shorten the driveshaft? Will there be any problems with the headers, downpipe?

I do need the m116 manual transmission flywheel if anyone has one for sale?

Any help/ input appreciated.
Thanks

[t walgamuth]

I would not have thought a v8 would fit a finney without some surgery.

[ScooterABC]

Unless your existing engine in the fintail is dead, why would you take this on? The M117 isn't terribly powerful compared to other engines you could fit and sounds like a lot of work.

[Tomguy]

Sounds like a fun project, although you might consider a 5.6 from a w126 or r107. About 100HP more, and if you really wanted, you could make it D-Jet to look "Old-school" (or otherwise just Megasquirt it, or another aftermarket setup for EFI).

I think you need to re-locate the brake booster, but otherwise, I don't think there would be major modifications required to the engine bay.

[fonzi]

W111 3.5 coupe had a modified firewall I thought.

Maybe compare to the w108 to some what matches a 4.5.

I think “tony H” or a similar handle is boring out a 4.5 to 5.6 to do a manual trans old school look with lots of torque. http://www.peachparts.com/shopforum/vintage-mercedes-forum/321240-project-iron-block-5-6-a.html

The 3.5 manual flywheel is still available from MB as I understand it, about $800-900.

[Tony H]

Yea it's been in progress for a while but my car was optioned with a manual V8 trans so some of the work is already done. You will be in it for many$ by time you address the flywheel, bellhousing, clutch, driveshaft etc. I'm working on a solution to install a T5 Mustang transmission behind the M117 but it's only the bellhousing I'm addressing at this point.
Swiss: I don't think the 6 cyl 4 speed(If that's what you are referencing) will fit on the 3.5 bellhousing. I think you will need a 3.5 manual transmission.

[rwd4evr]

Yes firewall is different in v8 cars. The booster and master aee moved over toward the fender. The pedals are different too. I can't say a v8 won't fit with the 6 cyl firewall but mother Benz changed it for some reason. A smaller booster may be necessary. Not sure on the 6 cyl trans to v8 bell but I do believe the shafts are different lengths. May be able to make it work but not sure. Your 3.92 or 4.08 rear axle is going to suck with a v8 as well. Best bet is get a w108 280se 4.5 donor car and get to cutting and welding. The v8 3.27 rear axle is key unless you adapt an overdrive trans. Flywheel is close to 1000$ new. There's a guy that says he's getting copies made by findanza which will be awesome if it happens. It will be an awesome car if you can get it together. I have similar aspirations but a few cars in line ahead of the fintail.

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[Tony H]

The ratios on the 3.5 box are not great-1st is so low it's a joke and they are way far apart. Really bad with the original 3.69. Not that great with a 3.27.

[rwd4evr]

Originally Posted by Tony H

The ratios on the 3.5 box are not great-1st is so low it's a joke and they are way far apart. Really bad with the original 3.69. Not that great with a 3.27.

Yep. I've got a 3.69 in my 450slc drift car. Don't get me wrong it's quick, but 1st is a very short launch and to get a little temp in the tires. I could pull away in second no problem. The ratios are kinda unbelievably the exact same as the 6 cyl cars. Not sure what they were thinking really. I'm completely out of gear at I think 125 mph at 6500 rpm. It gets there in a hurry though. They don't really shift fantastic either. My syncros are pretty shot(since I've had it). 1 -2 shift is grinding if I rush it. 2-3 is ok. I will say it takes a beating well. I broke the clutch disc sprung hub and welded it up solid and rebalanced it. The r107 v8 trans uses a spline that absolutely nothing else ever has used. Ive read that the w108/w111 use the
1 1/8 10 spline like the 6 cyl but I can't confirm that. Tony may be able to. Hang onto that bellhousing, I'm not saying don't go for the factory parts because they work but you can do better with some money and ingenuity. A mustang t5 is better alll day long but when you modify be ready for the domino effect. I'm very knowledgeable and pretty crafty, I've been reasearching and planning a 5 speed swap for years now. Fact is I'm still running stock parts. I could sell you close to everything you need to get it together but you will still have fabrication to do. Driveshaft, shifter, exhaust. The brake master is question mark. There is a 4.5 powered fintail built awhile back, full thread on it. I can't recall what he did about that. Price tag on the full flywheel, trans, clutch isn't small. Finding it laying around in bits won't be easy either. Scour every possibly location for a **** box 350sl/SLC and roll the dice if you find one. Me and fonzi have 4 of them between us but I'm not really inclined to let go and I don't think he is either. Using an alloy block 3.8,4.2,5.0,5.6 sounds awesome until you realize it's really a different animal in a similar skin. Nothing bolts up but motor mounts. Not even the oil pan. Luckily a w111 will take w126 oil pans. Not trying to tell you don't do it but there are obsticals. My dream of m119 dohc power in my 64 220b with a 5 speed is gathering dust.
Hate to say it but an LS swap makes more sense . Way more. But again, domino effect. Ask Tony. I've gone diesel for my street car. Maybe my race cars in the future too.

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[rwd4evr]

Mpg is another thing. My k jet 4.5 is maybe 200 hp with no emissions crap and it runs great but I get worse mileage on the highway than I do towing it in my 5.0 mountaineer. I would definitely be using a d jet engine converted to modern efi. Hell, you can turbo easily at that point.

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[fonzi]

Originally Posted by rwd4evr

Scour every possibly location for a **** box 350sl/SLC and roll the dice if you find one. Me and fonzi have 4 of them between us but I'm not really inclined to let go and I don't think he is either.

I’ve paid $2500+ for totally unknown potential POS non-running cars with the v8 manual, and kind of regret not buying some junk up to $5000 because they are so damn rare.

But to correct the above statement. It’s actually 5:

1) Jason’s 1978? 1979? 450slc drift car (US 450slc w 3.5 manual trans converted in). The only k-jet of the mix currently.

2) Jointly purchased gold 1972? 350sl 4-speed (has a 3.69 6 cylinder rear in it for some reason)

3) “Alonzo” stock (with cosmetic mods) 1972? 350sl 4-speed.

4) 1973? “450sl stick” which is a 350sl 4-speed that does some reason has a 4.5 in it.

5) my recently purchased (stock with cosmetic mods) 1973 350slc 4-speed.

And we also have two manual trans W108,
6 cylinder.

And Jason has two w111 Fintail manual sedans.

And Jason has two w110 manual trans cars in his shop too.

So yes, Jason is very knowledgeable on these topics. When I met him, he didn’t know as much as he does now, but I quickly identified him as someone with some serious skills.

[Tony H]

Wow-that's a lot. If I bought another car I would like a 350SL manual. When I bought my 3.5 coupe I specifically sought a stick shift. It took a while. I have kind of given up on finding a spare transmission-that's part of what is motivating me to find a aftermarket solution so I can put my transmission on a shelf unless I need to put the car back to original. A few years back a W116 3.5 stick shift was in a Pick n pull in N. Ca but we were moving and I could not make the 8hr trip to it. By time we were moved the car had been pulled.

[pedrocamp]

I have been collecting parts for a similar project... a 68 230 W110 M180 auto trans chassis rebuilt with the front sub-frame/disc brakes and 3.27 rear end/discs from a complete 72 280SE 4.5 M117 car I acquired a while back. I also bought a 72 350SL Euro 3.5 M116, 4 speed manual car and will use engine and trans from this chassis. I prefer the Euro 3.5 over the US spec 4.5 (more revs, more hp though lower torque and shorter deck height), will likely use the D-Jet system controlled by Mega/Microsquirt supplied ECU and MPS.
I understand there will be some work to the sheet metal around engine and trans as well as fitting the pedals but don't know the extent of it yet. I am envisioning my project as what would AMG have done in 72-73 if they had built a V8 powered W110 so more modern bits not applicable other than injection controls for $$ and reliability. AMG did build a 280SE powered W110 back in the day. I can't offer much advice yet but am interested in what those with experience with this type of build have to say here.

[rwd4evr]

I don't want to be thread jacking since the w110 build will not be the same as a w111 but I can tell you, I'm building a 67 230 w110 for a customer with a m130 and 4 speed and it's very tight even wirh parts they came from the factory with. I agree the euro 3.5 is better and it will help your brake booster issue since it 3/4" narrower but the problem I think you will have is that the subframe is moved rearward to facilitate a shorter wheelbase in the w110. So the motor mount arms for a 6 cyl w110 are different than a 6 cyl w111 to push the motor forward in relation to the subframe. To get an idea of how much look at your w110 6 cyl motor mounts, they are angled rearward, on a w111 they are dead straight. The engine is still closer to the firewall though. You may get away with the 4.5 motor mounts but it will be super tight on the firewall which could mean exhaust manifold and/or downpipe clearance issues. Possibly steering box as well. The v8 is actually just barely shorter than the 6 with all it's pullys and such so cooling is going to be tricky too. I'm getting a custom built rad from Griffin per the customer's request. If you have the car already and you are comitted it can be done but a w111 will save a bunch of headaches. Driveshaft will need to be rearranged as well. The bearing is in a different place on a w108 and it's longer.

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[pedrocamp]

Thanks for info rwd4evr. Yea, I'll have to look at and probably solve all the issues you mentioned. I am set on the W110 for sentimental and really for the challenge of doing it. A bit more unique in the end.
Has been done... found an un-credited pic on the net of a red W110 with a 3.5 and Ronal R9s, not sure if it was manual trans or not. Apologize to Swisscheese for taking over thread but it is along same lines as his project and likely quite a bit in common.