The 603 turbos are waaaay too large for the 602, at least in stock form. The flanges are different and it's not a bolt-on either. The 602 has a T2 (I think) and the 603 is a T3. The T3 on a 602 would be a total dog until boost finally builds. Maybe with those 7.5mm pump elements it would work better, lol...

OK I need to get into the specifics for just a bit -

1. As per above I'll run a direct line from VCV to tran vac mod, removing the two dampers that are currently used.

2. There is a vac line from BFS to ALDA. Do I plug that line?

3. I perform GSXR's wastegate pressure actuated conv.

4. I may then remove all vacuum transducers on pass side & BFS or driver side.

Am I correct?

TGD

1) Try it without any dampers, but you can also try one damper and see if there is any difference. I forget if I ended up using one or not.

2) It's a pressure line from the ALDA, but yes, disconnect and either remove or plug all unused hoses and tubes.

3+4) Correct - after the pressure wastegate conversion, THEN you can remove the tranducers on the passenger side for the old wastegate, EGR, and flapper valve.

4) The BFS is totally separate and can be bypassed / removed with or without the pressure wastegate conversion.

Right. I did not mean to suggest that the BFS had anything to do with the vacuum transducers on the other side or your wastegate mod.

My thinking as I wrote was that this is all the stuff I get to remove.

I've got about 5 to 6 weeks off, after my upcoming surgery and before the start of the next semester, and I'm hoping to pull the dash and replace all the vacuum actuators for the HVAC system & do the wastegate mod.

Always good to have a project or two!

Thanks again everyone. Your comments/suggestions/experience is/are (or is it are/is) appreciated.

TGD

Get a box and put all the removed components in it... and weight it.

My box of under the hood removals is about 25 lbs.

I guess I've added much of that back again as other components to the car, so there is no winning this weight race.

It's just fun to see "how much isn't required" by weight.

__________________
Cheers!
Scott McPhee

1987 300D

"Required" is a relative term. If the manufactures put it on/in, there was a reason. Maybe federal requirement or what have you.

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92 300D 2.5L OM602 OBK #59

True, true, required is a relative term. I see of lot of parts on the old Benz's that simply aren't required the for car as I need it now. Many parts were added into the design, I think, to meet Mercedes Benz's own standards of the day... Which have since changed and you won't find those parts on newer model years. 'round 93 is when the bean counter became more important than the engineer at MB and that's when the requirements shifted to "make it cheaper".

__________________
Cheers!
Scott McPhee

1987 300D

I understand what you're saying. I think they changed from a PSI activated waste gate to vacuum activated waste gate to meet emission requirements. People have change back to the PSI activated waste gate because it's more reliable and cheaper than the EDS controlled (vacuum activated) setup.

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92 300D 2.5L OM602 OBK #59

And also, more importantly, to disable EGR and keep nasty black soot out of the intake tract. Can't do that without the wastegate conversion.

I can't delete the EGR without also converting to the pressure wastegate???

On a 1990-up MB turbo diesel, yes, that is correct.

__________________
Dave
Boise, ID
Check out my website photos, documents, and movies!

On the 5 cylinder anyway. The W126 350SD/SDL do not use EDS to control the turbo

The W140 does use EDS for boost control.

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

Ah, that's right. I think there was an error in the factory docs, which state that the 90-91 603.970 engine has a vacuum wastegate, but it really does not. It's been a while since I checked into this.

The 92-95 603.971 definitely has a vacuum wastegate, and the 90-93 602.962 also has a vacuum wastegate. These cannot have the EGR disabled without converting to a pressure wastegate, or getting very creative with electronics to fool the EDS.

Thanks. I'll clean my EGR and put it back on then, till I get the new actuator.