true duals on an lt1 ? worth it ??
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From: EAST MOUNTAIN TEXAS
Re: true duals on an lt1 ? worth it ??
QUOTE=97 RedSS]True dual will gain you some hp Kris...as long as you dont have a problem getting it inspected and dont mind the sound, I'd do it...
Cody[/QUOTE]
AND WHERES MY OBD1 PCM .... LOL
Cody[/QUOTE]
AND WHERES MY OBD1 PCM .... LOL
Thread Starter
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From: EAST MOUNTAIN TEXAS
Re: true duals on an lt1 ? worth it ??
Originally Posted by 97 RedSS
I had one lined out but someone was wanting to sell their car 
Go 3" all the way!
Cody
Go 3" all the way!
Cody
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Posts: 2,985
From: In a house by the bay
Re: true duals on an lt1 ? worth it ??
'96 LT4 Corvette
Heads/cam 355 with bolt ons
2.5" dual exhaust, summit x-pipe & borla (3" in/3" out) xr-1 mufflers
428 rwhp/400 lbs-ft SAE corrected
Same car with 3.0" dual exhaust, summit x-pipe & same borla xr-1's
436 rwhp/ 405 lbs-ft SAE corrected on same dyno
more avg. tq & hp from ~3200 rpm up
-Mindgame
Heads/cam 355 with bolt ons
2.5" dual exhaust, summit x-pipe & borla (3" in/3" out) xr-1 mufflers
428 rwhp/400 lbs-ft SAE corrected
Same car with 3.0" dual exhaust, summit x-pipe & same borla xr-1's
436 rwhp/ 405 lbs-ft SAE corrected on same dyno
more avg. tq & hp from ~3200 rpm up
-Mindgame
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Posts: 627
From: Edmonton, AB, Canada
Re: true duals on an lt1 ? worth it ??
Area is proportional to radius squared but Flow is proportional to radius to the power of 4.
2.5^4 x 2pipes = 78.125
3^4 = 81.
Assuming a perfectly straight pipe and assuming air has zero viscocity and assuming the length of both pipes is exactly the same, the 3" single pipe will outflow the 2.5" dual by a factor of 81/78.125.
2.5^4 x 2pipes = 78.125
3^4 = 81.
Assuming a perfectly straight pipe and assuming air has zero viscocity and assuming the length of both pipes is exactly the same, the 3" single pipe will outflow the 2.5" dual by a factor of 81/78.125.
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Posts: 2,525
From: SoCal
Re: true duals on an lt1 ? worth it ??
Originally Posted by med_reject
Area is proportional to radius squared but Flow is proportional to radius to the power of 4.
2.5^4 x 2pipes = 78.125
3^4 = 81.
Assuming a perfectly straight pipe and assuming air has zero viscocity and assuming the length of both pipes is exactly the same, the 3" single pipe will outflow the 2.5" dual by a factor of 81/78.125.
2.5^4 x 2pipes = 78.125
3^4 = 81.
Assuming a perfectly straight pipe and assuming air has zero viscocity and assuming the length of both pipes is exactly the same, the 3" single pipe will outflow the 2.5" dual by a factor of 81/78.125.
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Posts: 652
Re: true duals on an lt1 ? worth it ??
Originally Posted by GREAT_WHITE
is it worth doing a dual exhaust on an lt1 ??? does anyone have any proven gains or coments on it ???? i was told a single 3" exhaust does better..... comments ?????
kris
kris
Last edited by Brettinator; Feb 19, 2006 at 12:34 PM.
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Posts: 454
From: So. Cal
Re: true duals on an lt1 ? worth it ??
After reading all this, this is what I'm going to do with my current rebuild. This will be a 355 with at least 450hp hopefully more according to DynoSim. 
This needs to be smog legal. Anyways 1 3/4" shorty headers with 3" collector. 3" to the 3" dual cats. Cats will act like a resonator box. Then neck down to 2 1/2" to my Flowmaster 2.50" to 3.50" Y connector. Than the 3 1/2 inch Mufflex system using a Magnaflow 3 1/2 inch muffler.
This needs to be smog legal. Anyways 1 3/4" shorty headers with 3" collector. 3" to the 3" dual cats. Cats will act like a resonator box. Then neck down to 2 1/2" to my Flowmaster 2.50" to 3.50" Y connector. Than the 3 1/2 inch Mufflex system using a Magnaflow 3 1/2 inch muffler.
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Joined: Jan 2004
Posts: 1,406
From: Downey, CA
Re: true duals on an lt1 ? worth it ??
Originally Posted by med_reject
Area is proportional to radius squared but Flow is proportional to radius to the power of 4.
2.5^4 x 2pipes = 78.125
3^4 = 81.
Assuming a perfectly straight pipe and assuming air has zero viscocity and assuming the length of both pipes is exactly the same, the 3" single pipe will outflow the 2.5" dual by a factor of 81/78.125.
2.5^4 x 2pipes = 78.125
3^4 = 81.
Assuming a perfectly straight pipe and assuming air has zero viscocity and assuming the length of both pipes is exactly the same, the 3" single pipe will outflow the 2.5" dual by a factor of 81/78.125.
parts of this thread, and especially the posts by Injuneer. I also suggest you
take a look at some gas law equations if you are really curious.
http://www.lmnoeng.com/DarcyWeisbach.htm
http://www.chem.mtu.edu/~fmorriso/cm...sible_flow.pdf
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Posts: 1,406
From: Downey, CA
Re: true duals on an lt1 ? worth it ??
Originally Posted by Brettinator
The only true comparison/benchmark would be if someone dynoed before & after comparing there old 3" catback followed by a 3" true dual setup which ran all the way to the rear bumper, this way backpressure benchmarking would be compared (keyword 3") to get a true comparison.
comparison, but logic would indicate that a 3" dual would perform as well
or better than the 2.5" dual in higher rwhp applications (as evidenced in
the Mindgame post). It's also difficult, without many dyno pulls, to verify
+- 5 rwhp. The original comparison was a flowmaster single to flowmaster
dual which netted a 12 rwhp gain.
http://web.camaross.com/forums/showthread.php?t=256932
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Posts: 652
Re: true duals on an lt1 ? worth it ??
Originally Posted by truedualws6
This is not 3" single to a 3" dual comparison, it's a 3" single to 2.5" dual
comparison, but logic would indicate that a 3" dual would perform as well
or better than the 2.5" dual in higher rwhp applications (as evidenced in
the Mindgame post). It's also difficult, without many dyno pulls, to verify
+- 5 rwhp. The original comparison was a flowmaster single to flowmaster
dual which netted a 12 rwhp gain.
http://web.camaross.com/forums/showthread.php?t=256932
comparison, but logic would indicate that a 3" dual would perform as well
or better than the 2.5" dual in higher rwhp applications (as evidenced in
the Mindgame post). It's also difficult, without many dyno pulls, to verify
+- 5 rwhp. The original comparison was a flowmaster single to flowmaster
dual which netted a 12 rwhp gain.
http://web.camaross.com/forums/showthread.php?t=256932
Thread Starter
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Posts: 335
From: EAST MOUNTAIN TEXAS
Re: true duals on an lt1 ? worth it ??
So It Pretty Much Comes Down To Is What You Would Prefer....being That Both Come Close To One Another....im Probly Gonns Go Ahead And Do The Dual 3" Since There Is Not A Whole Lot Of Difference... This Has Turned Out To Be A Very Good Post In My Opinion Due To Math Calculation And Feedback.... It Deserves A sticky 
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Posts: 652
Re: true duals on an lt1 ? worth it ??
Originally Posted by GREAT_WHITE
So It Pretty Much Comes Down To Is What You Would Prefer....being That Both Come Close To One Another....im Probly Gonns Go Ahead And Do The Dual 3" Since There Is Not A Whole Lot Of Difference... This Has Turned Out To Be A Very Good Post In My Opinion Due To Math Calculation And Feedback.... It Deserves A sticky
