apexman

I have a 98 Z28 M6 that put down 365 HP @ 5500 and 385 TQ at 4200 o a Mustang Dyno. I have bullet muffler with what looks to be a restictive custom dual out back. Just wondering what the gains might be with a cutout before the bullet in the I pipe. Also, I have Macs w/ stock cats w/ Mac Y pipe.
No pulley either.

I just recently did this camswap myself but have yet to get it to the track. I plan on going this friday as the 1/4 and trap is what I really want to see. This is a car I drive everyday and mainly do autocross in.

I ordered a cutout and will install it before I take it to the 1/4 this Fri. I ran it at 13.4 at 106 with a lid before. Should be alot better now.

Think I can gain about 10 HP?

apexman

Wow, no reply yet. I guess there are more readers and posters like myself on here. No worries.

I sure wish there were boards like this back when I had my '70 Firebird and '67 RS Camaro back in high school.

This board was a huge help for me the last month.

thanks

Cobraeater

What kind of catback do you have?(Sounds like a stock exhaust)

Anyway a cutout should give you at least 10 hp maybe more with that cam and headers, and you could put the cutout before or after the bullet since bullets flow well.

Lose the cats and you'll make even more power though.

SouthFL.02.SS

apexman, what's up. We met at an SFFBA meeting a couple of weeks ago (Black SS w/ the TSP 231/237 cam). Remember the difference between cutout open and closed on my setup? 20hp. Do it! Do it!!!
Hehehe, anyhow, post your track times once it's said and done with. Good luck!

PS. I'm going with X-pipe true duals next week.

WOT

iTrader: (1)

netted me only 7, but i guess every one counts.

andy98Z

iTrader: (4)

I have dual cutouts in my Y pipe. I made 440 with them closed and 453 open(mustang dyno). So my guess is you will make about 8rwhp, I have loudmouth exhaust. If you have a muffler it should gain more.

apexman

Thanks for the replies. I just had it installed today, as I don't have a welder YET!
I put it before my bullet muffler. The catback I have is basically stock with A bullet in the I pipe. So, hopefully it will do well. It does feel like it lost torque but hopefully will gain on the top end. That is what I expected. Will post results after friday.

SF02SS, I do remember you. I may try and make the meet this Thurs. but not for sure. Mine is actually kinda quiet I guess the cats keep it that way. You can hear the cam thumping better though!

SouthFL.02.SS

apex, your torque is all at the top now. Try doing a 65mph drop gear punch on the xpressway with the cutout open- you'll see where the torque went.