D-Jetronic replacement system - Page 2 - PeachParts Mercedes-Benz Forum

kip Foss · #16 05-31-2004, 07:31 AM

Kitcarlson

Check www.colectorcartraderonline.com for MB sls and slcs. They usually have atleast 70 slcs losted and hundreds of sls. Many slcs in the $2-3,000 range.

cth350 · #17 05-31-2004, 08:47 PM

another good candidate...

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2480732224

-CTH

psfred · #18 05-31-2004, 10:41 PM

Tobst:

I am unaware of any quick easy way to get more hp. Easiest thing to do is get a 3.5, but you really aren't getting that much more power, to say nothing of 96 octane fuel. A 6.9 would be next option, or a 560 M119, but both will require considerable work to install as they both use K-Jet injection. An M100 is both too expensive and too much trouble.

They will all use MORE fuel under normal driving conditions than the 4.5.

"fiddles" tend to be expensive when you find something out by causing a mechanical problem.

There are essentially no aftermarket parts to increase poiwer. AMG probably goosed the output quite a bit, but finding parts 30 years later is going to be a challange.

Peter

Tomguy · #19 05-31-2004, 11:00 PM

3.5 heads would require racing fuel, the compression is 12.6:1 with them according to calculations I did a while ago. If you want more power, going from a higher-torque 4.5 to a lower-torque same HP 3.5 isn't the way to go. Cams may be. The BEST would be a redesigned exhaust with less restrictions, and open the intake and exhaust ports up (on the head) a bit, and then smooth out the insides of them. Mod the manifold to take a wider throttle body as well - if you do that, and set it slightly richer, then under full throttle with the 10% mixture boost it won't be overchoked, due to getting more air -> more power!

For now... try cutting off the lower part of the air intake snorkel (where it's super narrow) and move the temp sensor up more, or cut the whole thing off, widen the hole, and design a larger snorkel. I figure this has got to be worth a good 15-20 HP alone!

j9fd3s · #20 06-01-2004, 09:51 AM

maybe i'll pull the air cleaner off on the dyno and we'll see

bumping the compression to 9-9.5 (like the 3.5) from the stock 8:1 would help too

kip Foss · #21 06-01-2004, 08:52 PM

Regardless of what you do to your engine, in the end you, still have a MB engine with all the related costs of parts and upkeep. If you are going to put something like a 6.3 in an sl of slc you have not only taken on a hell of a conversison job but you have created a car that is non-standard as far as retaining the originality of the car. You also not only still have a MB engine but now you have one that is much bigger than you need for the required HP, and you have an old style MB engine with really expensive parts on top of that.

If you are going that far you might as well put a 5.0 lt. Ford in there. I have a Euro 280slc parts car that someone tried to put a 5.0 into. Although the workmanship on the job was absolute crap the engine did fit with plenty of room around the bell housing (unlike the 350 Chevy conversion). Unfortunately he butchered the cross member rather than modify the oil pan. I think that if he had modified the pan and lifted the engine slightly it would have gone in nicely.

At least with something like a Ford the parts are reasonable and it doesn't require a fortune to get 300hp out of one. I am not pushing Ford but they do have a front sump oil pan. There may be other more promising engines out there (dual overhead cams, etc.) that will fit but considering the availability of Fords and their parts I think they would be a good choice.

psfred · #22 06-01-2004, 10:15 PM

If you are going to swap engines, why not just drop in an M119 5.6L? Only thing you have to change is the fuel/ignition, otherwise even the tranny will bolt right up.

Beats the pants off a Ford 302, and fits directly.

Peter

tosbt · #23 06-01-2004, 10:19 PM

Looks like this thread has come down to how to improve performance on my 4.5. We have been here before and unfortunally there is really not much one can do to the 4.5 to give it slightly more power without great modifications. Please understand that I realy like my 300SEL 4.5 much like it is, I do not intend to butcher it into something other that what it is. To me this car is a work of art. Could be improved a bit here and there, I would love a little more power. Maybe a really good set of Headders would do the job, maybe the 3.5 cams but as I see it from here there is not much more that could be done. Well thats OK, this is still one great car. Thanks for the advice all.

psfred · #24 06-01-2004, 11:04 PM

Tobst:

I seriously doubt you could improve even the headers much, given the lack of space and the fact that you have equal length runners on the right side now!

MB doen't make high restriction exhausts, they are pretty good right from the factory.

I'm in the process of taking the left manifold off at the moment. No way you are going to mash anything but something very similar to the existing mainfold in there, it's almost impossible to reach the nuts on the bottom now!

Peter

j9fd3s · #25 06-01-2004, 11:40 PM

Quote:

Originally posted by psfred
Tobst:

I'm in the process of taking the left manifold off at the moment. No way you are going to mash anything but something very similar to the existing mainfold in there, it's almost impossible to reach the nuts on the bottom now!

Peter

i hate the nuts on the bottom! if they made the damn thing 3" longer they would be so easy to get at from the bottom

mike

psfred · #26 06-03-2004, 12:48 AM

Yeah, I know!

I've got all but one off now (the bottom studs came out, which suits me fine -- better than breaking them off!!!! I'll locktite them in. I split the top nuts with a dremel tool using a cut-off wheel -- this is really the cat's meow! No way to get to the bottom ones, though, so I used a socket and extension.

I'm going to have to remove the pipe to get the last one out, no way to get to it from above. Will be easy once the pipe is out, but I'm going to have to drive it over to my brothers, I have a dead Volvo in the garage and I refuse to work under the car on a slope.

Unless I really bugger something up, I expect it will only take an hour or so to get the new manifold on from this point.

It never stops, does it?

Peter

kitcarlson · #27 06-08-2004, 03:56 PM

CTH350 generously sent technical information that will help in the application of the KitCarlson EMS for MB.

In the review of the information, since the original D-jet system used 2 groups of 4 injectors, only one EMS unit is required.

A conventional solid-state ignition with electronic dwell and timing is may be a better approach than going to a DIS system. The DIS would require mounting 2 quad coils and plug wire change...

These changes will reduce the cost by a few hundred dollars.

I feel a test D-Jet MB in my future.