500E exhaust manifolds

[revbond]

I have been told that in order to remove the exhaust manifolds on a 1992 500E, the cylinder head cover and possibly heads would have to be removed. Is this true? If not, what would be the alternate procedure? The W124 cd is not clear on the matter.

Thanks,

John

[This message has been edited by revbond (edited 03-01-2000).]

[Benzmac]

I have not had to take any off. Why are they coming off.?

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Benzmac:
1981 280GE SWB
1987 16V
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

[revbond]

I'm thinking about headers.

[jeffsr]

Well, just imagine what would happen if you had to remove your tranny or replace the exhaust (just in case it wore out). Whoever told you that to remove the exhaust manifolds required head removal was having a grand time with your psyche. What would Midas do?? I've never heard of that being necessary in any production passenger car (at least the kind most folks can afford).

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Jeff L
1987 300e
1989 300e
1987 BMW 325

Revbond,

I'm curious. Have you ever had headers on a car before?

Larry

[revbond]

Larry -

Only on my 2.3-16v, which comes with factory headers. Why do you ask?

John

[Lou Nielsen]

I've looked into headers for the 500E. Equal lenght stainless headers from RennTech are aprox $5000. I've also spoken with an exhaust fabricator / tuner. He felt that it could be done with great difficulty with little to gain for the money. His price approx. 2000-3500 depending on materials of construction. Per RennTech, no real horsepower gain from the headers is to be had until you move to a 6.0L motor.

Improvement in the flow of the stock manifolds is a possibility through extrude honing. I would experiment with some new (not installed) manifolds before I would do anything.

revbond,

I asked because if you had ever had aftermarket tubing exhaust headers, you would know the downsides to them. These negatives are; they are prone to leaks, they rust out over time (of course the stainless ones mentioned above obviously would not rust), they are somewhat noisy, and because they are an aftermarket item they usually provide obstructions to access of other engine components such as starters and the like. Also with many modern engine compartments, which are crammed in almost all cars these days, it's necessary to pull the motor, or at least raise it, to get them in place.

In my younger hot rodding days, headers were a great improvement for any Detroit V8. Almost every one of the Detroit engines came with EXTREMELY restrictive log type manifolds. Most aftermarket headers in those days were made with flanges that were too thin and leaked constantly. These leaks will occasionally warp an exhaust valve, if it happened to stop almost closed at the leaking header port. But in spite of all that, the improvement was worth the hassle.

On every Mercedes I've ever seen, the cast iron exhaust manifolds are impressive pieces. They always are layed out such that you can tell by looking at them that they flow well, not just a log with some openings toward the exhaust ports. I expect that the main reason for this is the fact that in Germany, cars are taxed(heavily) based on engine displacement. This means that M-B (and every other MFG in Germany) has to build cars that make the most power with the least displacement. Detroit can build horsepower with cubic inches instead of engineering efficiency into their standard motors. This of course has gotten better in the last decade or two.

I expect that the headers on your 190 were factory stainless items, well thought out for that car, and properly built. I wouldn't want to bet that I could get exhaust headers that good from the aftermarket.

So to wrap up my thesis here, I believe that you have very little and maybe even nothing noticeable to gain in return for a lot of hassle and potential maintenance problems in the future.

It's easy for me to make a lecture like this toward someone else, but at the same time, I understand the urge to make improvements.

That's my $0.02, I'm sorry it took you $100.00 worth of time to read all of it.

Good Luck,

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Larry Bible
'84 Euro 240D, 516K miles
'88 300E 5 Speed
Over 800,000 miles in
Mercedes automobiles

[Michael]

Inclined to agree with Larry..what gains do you expect?

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Best regards, Michael
'92 500E
'88 300TE