[Z06] Bolt ons, how much hp?
Thread Starter
Advanced
Joined: Jan 2014
Posts: 69
Likes: 0
From: Connersville Indiana
Bolt ons, how much hp?
Hi guys, I have a 02 z06, looking into ordering some stuff for it and wanted some people's opinions, or personal gains with minimal bolt on mods. Currently, I have LG super pro 1 7/8 longtubes, offroad 3in xpipe, LG big 3 catback, and a Vararam B2 in my shopping cart, ready to order. I have seen a lot of people make 400 with setups typical to this one, however, i just read a thread where some guy only made like 370 with pretty much this exact setup, except the longtubes were the street versions. This is a pretty pricey setup, so I would be fairly upset if I didn't make 400 or a little more, with a proper tune of course. Any dyno numbers/track times with setups similar to this one would be much appreciated. Thanks in advance, Devin 
Pro
Joined: Feb 2011
Posts: 579
Likes: 50
From: Chambersburg Pa
Unless you plan on doing heads and cam you are better to go with 1 3/4 headers and hi-flow cats.The factory cat back is fine.My 04 Z06 with headers and Vararam with conservative street tune dynoed at 374 rwhp. These cars dyno stock about 350-355.If anyone claims 400 rwhp from headers,cai and tune then they are on a very generous dyno or fudging the numbers.
Thread Starter
Advanced
Joined: Jan 2014
Posts: 69
Likes: 0
From: Connersville Indiana
Unless you plan on doing heads and cam you are better to go with 1 3/4 headers and hi-flow cats.The factory cat back is fine.My 04 Z06 with headers and Vararam with conservative street tune dynoed at 374 rwhp. These cars dyno stock about 350-355.If anyone claims 400 rwhp from headers,cai and tune then they are on a very generous dyno or fudging the numbers.
Instructor
Joined: Aug 2006
Posts: 142
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From: Orange County California
Sorry, just seen they do. Wasn't an option when I got mine. I'd get the 1 7/8" leaves you room to grow later if you get more cubes. If not going to go bigger cubes later, the 1 3/4".
Last edited by kwik ws6; Mar 29, 2014 at 02:12 AM.
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Racer
Joined: Dec 2007
Posts: 472
Likes: 12
From: Ontario
Burning Brakes
Joined: Aug 2013
Posts: 896
Likes: 6
From: Dallas TX
Just dynoed my '04 Z06 only 2 weeks ago with 1-3/4" Long-Tubes, Catted X-Pipe, Vararam, Borla Axle-Back + Tune...
Put down 391/379 which I've been told is about standard for our cars. Getting to 400 with these mods is VERY rare.
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VPP
Put down 391/379 which I've been told is about standard for our cars. Getting to 400 with these mods is VERY rare.
--
VPP
Racer
Joined: Oct 2006
Posts: 286
Likes: 18
From: Rochester MI
Most guys I've spoken with say if you go 1 7/8 header instead of the 1 3/4 in a standard intake and exhaust LS6 bolt on car, you will be about 10whp and 10 torque shy of what it could have produced.
Racer
Joined: Dec 2007
Posts: 472
Likes: 12
From: Ontario
So your saying the larger tubing is actually robbing power with the standard 'hardware'?
Burning Brakes
Joined: Dec 2003
Posts: 1,243
Likes: 5
From: Loveland CO
that will be everything in front of the throttle body.. Air Filter, Air Bridge over radiator and coupler connecting to the TB.
larger Primary tubes on the LT headers will give you better power if you do a cam and/or ported heads. Stock cam/heads it will not gain anything... So it will be something you need to figure out what you want for your power goal and budget. If you are doing a cam then get the larger primaries, if you are keeping stock cam then get the smaller primaries.
S
Racer
Joined: Oct 2006
Posts: 286
Likes: 18
From: Rochester MI
Absolutely! The smaller 1 3/4 header helps keep the exhaust velocity on a standard 346ci. It has been proven time and time again that the 1 3/4 headers make more power then the larger 1 7/8...I believe they are good to mid 500whp then the 1 7/8 is appropriate exceeding that pwoer level. I don't know why people seem to disregard the professionals that produce the headers and/or the dyno results. The proof is on paper and the best tuners will advise you to go with the 1 3/4 unless it's a blower car or a large cube motor. The car just makes more hp and torque plain and simple.
Drifting
Joined: Apr 2008
Posts: 1,464
Likes: 32
From: Ocala FL
Look at the guy who just posted his dyno results above.
"Just dynoed my '04 Z06 only 2 weeks ago with 1-3/4" Long-Tubes, Catted X-Pipe, Vararam, Borla Axle-Back + Tune...
Put down 391/379 which I've been told is about standard for our cars. Getting to 400 with these mods is VERY rare."
From another thread -
Toque - "2004 Z06 here.
This is what I got with LG Pro Long tubes (1-3/4), Vararam, air bridge, B&B bullet cat back, and Dyno Tune.
To the REAR wheels - 390 HP, and 378.8."
My '04 put down 392/377 with 1 7/8 Kooks headers, no cats, Vararam, and tune. Pretty much identical and I've seen plenty of dyno threads over the years on this forum to back this.
Drifting
Joined: Jan 2014
Posts: 1,285
Likes: 164
From: MA
Nah, this doesn't hold water. Results are typically identical.
Look at the guy who just posted his dyno results above.
"Just dynoed my '04 Z06 only 2 weeks ago with 1-3/4" Long-Tubes, Catted X-Pipe, Vararam, Borla Axle-Back + Tune...
Put down 391/379 which I've been told is about standard for our cars. Getting to 400 with these mods is VERY rare."
From another thread -
Toque - "2004 Z06 here.
This is what I got with LG Pro Long tubes (1-3/4), Vararam, air bridge, B&B bullet cat back, and Dyno Tune.
To the REAR wheels - 390 HP, and 378.8."
My '04 put down 392/377 with 1 7/8 Kooks headers, no cats, Vararam, and tune. Pretty much identical and I've seen plenty of dyno threads over the years on this forum to back this.
Look at the guy who just posted his dyno results above.
"Just dynoed my '04 Z06 only 2 weeks ago with 1-3/4" Long-Tubes, Catted X-Pipe, Vararam, Borla Axle-Back + Tune...
Put down 391/379 which I've been told is about standard for our cars. Getting to 400 with these mods is VERY rare."
From another thread -
Toque - "2004 Z06 here.
This is what I got with LG Pro Long tubes (1-3/4), Vararam, air bridge, B&B bullet cat back, and Dyno Tune.
To the REAR wheels - 390 HP, and 378.8."
My '04 put down 392/377 with 1 7/8 Kooks headers, no cats, Vararam, and tune. Pretty much identical and I've seen plenty of dyno threads over the years on this forum to back this.
