Question about striaght pipes
Question
I have cutouts after the cats on my truck..that bypass the muffler..it's loud and the SOTP is noticable with the exhaust uncapped. I am confused as to how this leans things out if you have the cats still..?? Excuse my stupidity but the lean condition makes no sense to me.
Bad for the motor??
Sorry, but no way.
Most of you know my setup, for those that don't:
Long tubes, Electric cutouts and custom mid pipes, O2 sims and Bassani cat-back....in that order. No cats.
I have dyno proven 1psi higher and 40hp with the cutouts open.
I'm still surprised to read that people lose boost. I know I gain every time I open the cutouts....I can do it on the pull and see it go down on the dyno boost feed.
I know that when I put on the KB and went to a 30 psi gauge, it was next to impossible to read 1 psi. Seriously, look at the guage while at full throttle and tell me, with the earth screaming by, that you can tell the differance between 18 and 19 psi. Even with the Eaton and less boost, it's tough.
Not to mention the error factor with the Autometers that most guys run.
The dyno (if you don't know) can read fractions of boost...so I consider it more reliable.
I have never had lean issues (beyond dialing fuel pressure and the boost-a-pump in) as a result of this setup.
I also imagine that my cylinder pressures are lower with the less restrictive system...that usually would equate to a more reliable, less stressed powerplant--particularly when using N2O.
Personally, I don't see...nor have I experianced...a drawback.
The sound of the truck at full throttle is almost un-explainable...just crazy phucking loud.
- Andy
Most of you know my setup, for those that don't:
Long tubes, Electric cutouts and custom mid pipes, O2 sims and Bassani cat-back....in that order. No cats.
I have dyno proven 1psi higher and 40hp with the cutouts open.
I'm still surprised to read that people lose boost. I know I gain every time I open the cutouts....I can do it on the pull and see it go down on the dyno boost feed.
I know that when I put on the KB and went to a 30 psi gauge, it was next to impossible to read 1 psi. Seriously, look at the guage while at full throttle and tell me, with the earth screaming by, that you can tell the differance between 18 and 19 psi. Even with the Eaton and less boost, it's tough.
Not to mention the error factor with the Autometers that most guys run.
The dyno (if you don't know) can read fractions of boost...so I consider it more reliable.
I have never had lean issues (beyond dialing fuel pressure and the boost-a-pump in) as a result of this setup.
I also imagine that my cylinder pressures are lower with the less restrictive system...that usually would equate to a more reliable, less stressed powerplant--particularly when using N2O.
Personally, I don't see...nor have I experianced...a drawback.
The sound of the truck at full throttle is almost un-explainable...just crazy phucking loud.
- Andy



Nuff said, thanx Andy.