So I recall that that 2000-2002 have revised manifolds which flow better than years previous to 2000, and am wondering what kind of HP headers are worth? I assume nobody has dyno'd before and after? From what I can gather we are talking maybe 9-12 RWHP more max.

There was another thread on this site were it was discussed that these 3800s as a daily driver primarily will benefit most from mid-length headers, as opposed to long-tubes -- so that is the assumption I am working with here.

Current power mods:
Borla Cat-Back, DMH E-Valve (still to be installed), SLP CAI & Bilsteins,Auburn LSD, Whisper Lid, Ultra Z style Ram Air hood.

 

With your manifolds you will not see signifigant gains on a stock 3800. The redesign made access to the plugs much easier and they have really good flow characteristics that rival headers on a stock engine. If you plan any internal mods to the engine like a cam or what not then yes the headers are the way to go, if you have the old style manifolds (95-99) then yes you will see small performace gains but most of all changing plugs will be better.

Hope this helps.

Massey

 

Thanks, but I wonder if there is still much left on the table, per:

*- Camaro Home Page Tom Henry Chevrolet

"Inside the right exhaust manifold in the area circled is where we believe there is exhaust flow turbulence and restriction."

 

Yes that sounds about right due to the angle that that tube joins the others but like I said with a stock engine you will not really notice anything. The Tom Henry Camaro has a highly modified engine that would lose quite a bit of power with the stock manifolds.

Massey

 

According to the article, the headers, a whisper lid, and an "updated computer programming", gave a gain of 13 hp over their previous test. Also keep in mind that's on an already modified engine. Your gain results will vary, likely to be lower. To me, that's a high dollar to hp tradeoff.

 

I am debating what's the next best bang for the buck for a little more power out of this V6 -- this seems like the next "easy" mod to do... Any others I should be considering?

I also thought about replacing this S-Pipe restriction with all 3 in. pipe to match my Borla catback and adding a high-flow cat. Wonder if I would loose low-end torque by doing this?

 

Once your out of the header area it is all about restictions. While the S pipe and Cat might restrict you at 5500 to 6000 RPM range I find it hard to believe you would have any effect under 4000 RPMs.

Remember all of the HP gains you read about are at RPMs our daily drives never see. I have my OBX headers and a guted Cat with a 2-1/2 hybred flowmaster Cat back with a Magnaflow muffler spliced in. If I upgrade to the Best exhaust money could buy I would bet I would not feel the differents under 4000 RPMs.

 

^ That's helpful Gorn, and you almost seem to imply that the S/Cat area might help low-RPM power?

So you lead the next question -- what are the best ways to improve <4000 RPM performance then?

 

Cam, but then you would still want/need headers.
Gears, stall, shift kit.

 

If the hi flow Cat helps at lower RPMs it is because of it condition Cat not its design. I had no change in butt dyno or Ipod pocket Dyno when I gutted the Cat.

I would think new increase ratio rockers would be the best bang for the buck for a daily driver. When you do a preformance Cam you change the Cam profile and you open the valve higher(lift) and faster(duration). This is really felt at the higher RPMs and can hurt lower RPMs. Rockers just cause the valve to open more but they still have the same duration. This will not shift your torque curve to higher RPMs, Dyno results of this upgrade would not show much Max HP because the larger lift and stock duration of the stock Cam profile/rockers would cause the valves to not be happy over 5000 RPMs.

Its also a pretty easy mod to do and undo if you don't like it.