who here races with exhaust manifolds?

[sixtynine]

Hi - My 69 Chevelle has manifolds and was thinking of getting her to the track BUT.... was interested to see what folks are running ET / MPH wise with stock or ported exhaust manifolds... anyone?

On a side note, my car looks like a stock 396/350 hp car but dyno'd 450hp/530 tq with cast iron GM intake & a Qjet (albeit with dyno headers)...

[Postsedan]

All the Pure Stock racer run them.... http://www.purestockdrags.com/

Dan

[sixtynine]

Yeah I know but asked for some advice over there but didn't get any sort of response....

That said, I only want to run low, low 12s... If I could do that with unported manifolds it'd be a bonus.

*Spoke to Greg Gessler and he has zero room to accomodate any further manifolds for porting due to time....

[protree68]

i watched a stock ZL1 on the dyno it made 430 hp with manifolds we tried headers and it was a hole differant animal on the first pull it made 518 hp.i had my manifolds for my car ported by the vorteck pro.

[mockingbird812]

<span style="font-style: italic">.... was interested to see what folks are running ET / MPH wise with stock or ported exhaust manifolds... anyone?</span>


'70 Chevelle LS6/M22/4.56 pure stock rules: 12.2 @ 108 mph

[Chevy454]

Been racing Pure Stock since '99...car has ran a best of 11.72 @ 118 so far @ 3700+ lbs...L72/400/4.56 Yenko Camaro.

[sixtynine]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chevy454</div><div class="ubbcode-body">Been racing Pure Stock since '99...car has ran a best of 11.72 @ 118 so far @ 3700+ lbs...L72/400/4.56 Yenko Camaro. </div></div>

Thats a real good mph for manifolds..... Are they untouched or extrude honed or ported?

[Chevy454]

Untouched, other than a shot of &quot;Cast Blast&quot; spray paint...

[Ryan1969Chevelle]

Hi fellow Canadian.

Plan to attend PSMCDR in September everyone I have met there has been great, I bet they would share lots of information to help.

Ryan

If you need directions follow me, I will be attending as a spectator again this year.

[Vortecpro]

Protree, its Vortecpro, get it strait.

[VintageMusclecar]

OEM iron BBC manifolds will easily support 425+ HP, which is enough to take a well-sorted 3800 lb car well into the low 12's (depending on elevation, track/weather conditions, etc.)

[sixtynine]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mockingbird812</div><div class="ubbcode-body"><span style="font-style: italic">.... was interested to see what folks are running ET / MPH wise with stock or ported exhaust manifolds... anyone?</span>


'70 Chevelle LS6/M22/4.56 pure stock rules: 12.2 @ 108 mph </div></div>

M22..... yeah!

[mockingbird812]

w/ an M22 is talent for sure. That was done in 1983 by the then owner David Bunn and he set an IHRA World Record with those numbers. <<GRAEMLIN_URL>>/laugh.gif

[sixtynine]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mockingbird812</div><div class="ubbcode-body">w/ an M22 is talent for sure. That was done in 1983 by the then owner David Bunn and he set an IHRA World Record with those numbers. <<GRAEMLIN_URL>>/laugh.gif </div></div>

yeah, I used to race mine with a stick for years then gave in a swapped in a TH400 (eventually ran 11.30s at 121)... changed car a few years back missing the stick and now have the urge again to race but wanna keep it 4 speed / stock appearing.

[JLerum]

Last dyno session I saw was 35 HP between headers and exhaust manifolds. I think it is more if the carb was tuned for the headers. The cam is a 143 dimension spec cam. The more horsepower you make the more it hurts.

I run a 4 speed with the manifolds. Shift a 6000 to keep it real.