603 IP differences (eg late model .97) - PeachParts Mercedes-Benz Forum

awsrock · #1 06-07-2014, 08:22 PM

I have read a lot of the previous discussions regarding the .96 and .97 IP differences, and the effect of having an early .97 on a .96 engine can have, but I was curious about the later model .97 IPs. Seeing as the HP rating increased in 94-95 models (maybe 93 too?), my question is, are all of these differences still based on the stock max fueling? For example, the early 3.5 has 134 hp and later had 148 or 150, but did they just adjust the full load from the factory? If so, how does that explain the same torque numbers?

I know there is more to it than just this (such as larger displacement of the 3.4), but for argument's sake, people would say the early .97 only made 134 hp, but at the same time it was at 4k rpm, which if that was dragged out to 4600 like the .96, would still be around 153 hp which is pretty close to the .96 settings. Could the power increase on the later w140s been from the better exhaust manifold??

I'm just trying to figure out if there would be any benefit from trying out a later model .97 IP. I was thinking about going that route for a mild performance upgrade, or possibly looking into the 6mm swap for my current IP. I have an SDL and spend most of my time in it cruising the highway, so passing power/ on ramp acceleration is more of my interest than raw max hp (although I wouldn't mind that either!)

Anyway, if there is any more info or ideas out there, I'd be interested in hearing about it!

winmutt · #2 06-09-2014, 03:20 PM

Same size elements I believe so the only real differences would be internal adjustment. If you want I'll sell you my old pump which had a few screws turned.

Also without a cat, the official MBZ output on a 603.960 is 168hp.

awsrock · #3 06-09-2014, 04:37 PM

168 with the pump maxed out, or just without the cat?

PM sent about the pump

winmutt · #4 06-10-2014, 12:24 PM

Just without the cat. Found it in a euro FSM once.