DrZ1

Is there a big ( worth the money) difference in spool up or overall performace with stock afm and 26/8 turbo.

thanks
Steve

LFA951

NO

billindenver

Keithr726

No, only if you have a aftermaket turbo and make more than 400hp.

Cory9584

a testpipe is catless. and i dont think youll notice much of a difference at lower power levels unless its clogged. It does sound better without a cat imo though.

reno808

YES SIR

nize

those of you who said 'no', have you performed a before/after dyno test? what are you basing your statement on?

i have performed a before/after dyno test between the stock exhaust (with cat and muffler) vs. the lindsey full 3" system (without cat and with edelbrock 3" rpm muffler) and there is a noticable difference in torque, and quicker turbo spoolup. there is almost no difference in hp though.

because it lowers spoolup substantially, a 3" exhaust system (or at the very minimum, a test pipe) is definitely worth the money on a 951 in my opinion, even if everything else is stock.

documented and proven, not theory nor speculation;

boston951

nize, I like the sound of that (no pun intended). BTW, kudos to you for using emperical data to support your answer.

PorscheDoc

Very interesting. I tested a 2.5" exhaust (no cat) vs a 3.0 Lindsey on a stock car and the gains were 4hp and 7tq as testing on my mustang.

nize

the gain is minimal, but the curve is much better and gives you more 'area under the curve' because it increases spoolup speed.

do you have a before/after graph? post it up!

PorscheDoc

Where are those gains?

Duke

The main restriction is the stock cat. If you ever looked through one (well tried) you would discover that you can't even see sunlight trough it.

A catless 2.5" vs 3" would not differ by much on a stock car (as Doc reports)

nize

yes. the big difference is the stock cat vs. straight-through.

DrZ1

This is what I expected, thanks for all responses. Next question, will the turbulance of the gutted cat be much improved by a staight pipe?


and

Which muffler would be better the stock and slightly,maybe 25%, louder then stock set up(being catless)


Thanks Again
Steve

Mike1982

My cat was plugged, so when I put a test pipe on alone I got 3 more pounds of boost. Had to turn my MBC down then but still felt like more punch and quicker spool up after that.