Exhaust Question
 

I have no doubt there are many opinions on this board about exhaust systems. My question concerns switching from "true headers" like CMI to a more dependable Stainless Marine Gen 3 manifold system. Around a 1000 horsepower..........any performance loss?????

If Supercharged (especially postive displacement), engines care less about tuning lengths and ID's than Naturally Aspirated. They, however, want as least restrictive as possible with sizes 'within reason.'

At 1000HP you will have no HP loss (or torque if supercharged) using the Gen III with 4 1/2 or 5" tailpipes.

Gen 111's make more power on blower motors from what I hear. I have a couple sets waiting for the fountain if you want to put them on for mock up and measurement. I'll be back in the shop tomorrow if your around herb.

Interesting comments. 1/2 the price and no disadvantages. Seems to good to be true. Yes, I can come by tomorrow. Actually have a pair coming to see if they fit in between the 2 engines ok. Just ordered them this afternoon. If you have a pair maybe I can call first thing in the morning and tell them not to send out. Save some time and money.

CMI's are a piss poor example of a "true header". If you look at the runner length in a Stainless Marine gen 3 and a CMI it's got to be pretty dam close.

Well I don't know about the runner length being equal, but CMI is pretty much the only game in town for headers these days aren't they?

How much better are the SM 3s vs the GILs?

TTT.

How much better are one over the other. Throw in the PF Marine headers that lightning sold too. Those castings has big runners.

Stainless yes. Aluminum I think the Thunder and lightning are a much better setup. Diamond Performance bought the molds from KE. Although they look hideous I believe they are the best performing exhaust on the market. I'm happy with the Stailess Marine Gen 3's but if I had it to do over again I would probably go with the Thunder and lightning's. Some want the bling of the CMI's but me personally I wish my hatch would never have to come open.