380SL Diesel Conversion Project - Page 3 - PeachParts Mercedes-Benz Forum

t walgamuth · #1 11-30-2011, 01:29 PM

He'll find out!

A little vibration may not be an issue. It is after all a sports car!

mach4 · #2 11-30-2011, 06:38 PM

Quote:

Originally Posted by t walgamuth

A little vibration may not be an issue. It is after all a sports car!

I'm expecting some additional vibration... how much, I'll just have to find out. If it's too bad, I've got several choices, including going back to the original engine mounts. Other options include drilling out portions of the urethane to make it softer, or filling with a softer urethane. I'm fairly soft now, but can go quite a bit softer.

This strategy is normally used to firm up the engine for performance reasons. For the track many people go with solid mounts that are terrible for vibration, so this solution is kind of in between normal soft mounts and solid mounts.

mach4 · #3 12-06-2011, 07:48 PM

Today was focused on getting the subframe spacers done.

I'm a member of the local EAA (Experimental Aircraft Association) chapter and they have a couple of lathes at the hangar that are available to members, so I was able to go down there and log some lathe time.

They will never win a machinist award, but they are functional. I made them a little more than 1/2" but I can just turn the shoulder a bit if I end up with better hood clearance than I'm anticipating.

Druk · #4 12-10-2011, 02:48 AM

Quote:

Originally Posted by mach4

Today was focused on getting the subframe spacers done.

I'm a member of the local EAA (Experimental Aircraft Association) chapter and they have a couple of lathes at the hangar that are available to members, so I was able to go down there and log some lathe time.

They will never win a machinist award, but they are functional. I made them a little more than 1/2" but I can just turn the shoulder a bit if I end up with better hood clearance than I'm anticipating.

Are you still having to go down this spacer road? I would be concerned that by spacing the subframe away from the body you're going to alter the angles the steering box and idler arms make with the tierods to the wheels. Have you done a trial lock -to -lock with the steering? I ask because I'm in the throes of a similar conversion and at full lock the inner balljoints are very close to the sump edge both sides. By dropping the engine relative to the center tierod that clearance may be gone. Being in the UK I have a different problem. Whereas your steering box fouls the oil filter, on a right-hand-drive car it's the exhaust downpipe that has no place to go; the steering box being on the opposite side.

mach4 · #5 12-10-2011, 03:33 AM

Quote:

Originally Posted by Druk

Have you done a trial lock-to-lock with the steering? I ask because I'm in the throes of a similar conversion and at full lock the inner balljoints are very close to the sump edge both sides.

Hmmm... No I haven't, but I should be able to get the subframe back in the car this weekend and check. I just need to get the urethane poured in the subframe mounts and it will be ready.

Which sump are you using? And which engine?

Remoting the oil filter is a relatively simple task compared to "remoting" the down tube. What is your plan?

Druk · #6 12-10-2011, 04:18 AM

I'm using the 606 turbo engine which has an ally sump. The engine is inclined naturally so doesn't have the same height issues. The down tube is being routed in front of the main subframe Xmember which is where the original went in any case. My car was a Euro 280SL in it's past life

. That will require the turbo to be re-mounted back-to-front with the Xhaust outlet facing the rad but that is a minor job.
BTW, I'm using the same type rubber feet as you but uprating to the petrol 500 V8 version. I did a deflection test on the original 280 mounts and compared that to the hydraulic ones that came from the W210 donor car. The difference was 1.5mm more for the 280 ones. Almost insignificant but I'm going to the V8 ones which have a harder compound (I'm reliably informed). Interesting that you filled yours with urethane. I'm now looking at sourcing some of the same in the UK. My original ally engine feet are way out so will be fabricating new ones to suit the mounts using 10mm steel.

There's a member of the UK Mercedes-Owners-Club who has the same engine conversion as you in an R107. Unfortunately, he's not on the Club forum so I can't ask him questions.

mach4 · #7 12-10-2011, 11:34 AM

Quote:

Originally Posted by Druk

I'm using the 606 turbo engine which has an ally sump... That will require the turbo to be re-mounted back-to-front with the Xhaust outlet facing the rad but that is a minor job.
BTW, I'm using the same type rubber feet as you but uprating to the petrol 500 V8 version... Interesting that you filled yours with urethane.
There's a member of the UK Mercedes-Owners-Club who has the same engine conversion as you in an R107. Unfortunately, he's not on the Club forum so I can't ask him questions.

Sounds like a great project. I look forward to comparing notes. Too bad the guy in the UK club isn't on the forum, it would be nice to have the benefit of his experience. One of my goals with the build thread is to document my thinking and solutions for those that might want to tackle a similar project.

Your downtube solution is elegant.

Did you have to clearance the subframe at all with that engine?

Isn't that engine electronically controlled? And if so have you figured out that aspect? I made the decision to stay with a completely mechanical engine to avoid any of those hassles.

mach4 · #8 12-11-2011, 08:10 PM

Quote:

Originally Posted by Druk

Have you done a trial lock-to-lock with the steering? I ask because I'm in the throes of a similar conversion and at full lock the inner balljoints are very close to the sump edge both sides.

Well looks like I'm going to be ok. Did a temp install of the subframe, installed the drag link and laid my original pan on the crossmember. With the steering at full lock I've got plenty of bottom clearance.

And side clearance is ok too. It's a bit close in this picture, but I've gone with the "smooth" pan and so have plenty of extra space over what this picture shows.

I had to add more urethane to the subframe mounts as I mis-calculated the amount it would take... it really takes quite a bit. Here is how the spacers work in the car, dropping the subframe about .6 inch. Bad news is that the mounting bolts aren't long enough, so I'll have to source longer bolts before actually doing a final mount of the subframe.

Started work on the radiator. Here it is mocked up in position so I can begin to fabricate the bottom mount. The top mount will be really simple as I can use the original clips from the 300D, just need to cut some slots for the clips.

Ran out of time for the other things I wanted to get done, but all for another day.

Druk · #9 12-12-2011, 03:08 AM

Quote:

Originally Posted by mach4

Well looks like I'm going to be ok. Did a temp install of the subframe, installed the drag link and laid my original pan on the crossmember. With the steering at full lock I've got plenty of bottom clearance.

Excellent. Are you planning on shortening the road springs slightly to maintain the body height?

mach4 · #10 12-12-2011, 10:42 AM

Quote:

Originally Posted by Druk

Excellent. Are you planning on shortening the road springs slightly to maintain the body height?

No plans for right now. It's only 1/2" so it might not make a discernable difference. In fact the extra engine weight may take care of most of that. I'll just wait and see what I've got. I do plan on turning down as much of the spacers as I can once everything is in, running and settled.

Still too many moving pieces.

whunter · #11 12-06-2011, 08:12 PM

all pictures to this thread

vstech · #12 12-06-2011, 09:43 PM

Quote:

Originally Posted by whunter

all pictures to this thread

I edited the thread and substituted locations so all the pics are on our server.

unkl300d · #13 12-15-2011, 09:30 PM

Very neat !!

jusme · #14 12-28-2011, 10:05 PM

I REALLY want to do this, REALLY WANT TO. I will bookmark this thread for sure. I may need a few pointers via private messages, hehehe. Seriously though, way to blaze that trail.