Cutout Gains For FI vs. NA
Cutout Gains For FI vs. NA Just wondering if the gains for the forced induction crowd were significantly better vs the guys that are naturally aspirated.
I have seen gains of 5-10 horsepower for some NA guys, but I wondered if its the same for the procharger guys mainly, as well as turbo gurus.
If you have graphs....post em up.
I have seen gains of 5-10 horsepower for some NA guys, but I wondered if its the same for the procharger guys mainly, as well as turbo gurus.
If you have graphs....post em up.
Depends on the rest of the exhaust setup, on my ltd going open 3.5" cutout vs through 6 mufflers gained me zero mph at the track with a lot of testing. All straight through 3" mufflers though and mandrel bent nice exhaust.
That's crazy. You'd think you would pick up atleast a couple mph. If you had chambered mufflers i bet it would have made a difference
When I had the APS twins @ 7psi before, one dyno session I dynoed 571rwhp. Everything else staying the same, all we did was close the electric cut-out that I had on the I-pipe and I literally lost 70rwhp to the tune of 501rwhp. SEVENTY RWHP!
Summary: Turbos hate backpressure. <That's a period
Summary: Turbos hate backpressure. <That's a period
Trending Topics
This was with the same boost controller settings, just opening the cutout. Less backpressure after the turbine allows more heat extraction and more turbine speed so you get more boost. So with the same settings roughly 50hp
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo surprisingly enough, I am in love with the exhaust setup I have for the street. Its just the right sound, and loudness. I am pretty sure is would be a major restriction though.
Roll Tide. (notre dame goin down)
I picked up 70rwhp by opening my cutout with the d1sc, but I had pacesetter headers too. What size headers are you running? I would say 2" are needed with your setup. I just put some kooks 1 7/8 on mine.
It is just what Justin said..... all depends on the power level and the capacity of the exhaust behind it
I have a full single 3" exhaust that has two mufflers in series, very quiet........... at 15psi boost i see a big time jump when i open the cutout
But friends that have a nice full length 4" exhaust say they dont see much of anything till they have the, boost up by 20+
On similar engine combos and turbos
I have an electric cutout..... but it gets old having to open and close it all the time
I am swapping to a trick SS boost actuated pneumatic cutout, it opens under power, shut when not
I have a full single 3" exhaust that has two mufflers in series, very quiet........... at 15psi boost i see a big time jump when i open the cutout
But friends that have a nice full length 4" exhaust say they dont see much of anything till they have the, boost up by 20+
On similar engine combos and turbos
I have an electric cutout..... but it gets old having to open and close it all the time
I am swapping to a trick SS boost actuated pneumatic cutout, it opens under power, shut when not
i dynoed a buddies D1 car open vs closed. low boost (7#'s), kooks lt's to a mufflex 3.5" or 4" with a spintech. didnt gain ****. like nothing. i would have lost money on that bet
before people flip out on the graph, its showing the AVERAGE numbers for the graph, not max. max was 487/460
before people flip out on the graph, its showing the AVERAGE numbers for the graph, not max. max was 487/460
My car picked up about 25rwhp with the cutout open at 12psi or so. It has a full 3" exhaust/magnaflow muffler with a mpt70. I think the turbine is more of a restriction than the exhaust is. I did loose a some power with the air filter removed though. I have some of the graphs somewhere I will see if I can find them.
My headers are 1 & 7/8ths.
My exhaust cutout will be electronically controlled by a key fob. Cuz I am not getting down there over and over. Call me lazy, but its only 79.99 extra for it.
My exhaust is the slp loudmouth plumbing with a dynomax resonator. I will not change it. It's a neat sound that I am not willing to part with.
Well, those gains seem to be pretty significant at times. Not sure why tally didnt gain anything. Maybe 7 lbs on the D1 was not enough pressure to really notice. Thats strange that it would not even gain 1hp though.
My exhaust cutout will be electronically controlled by a key fob. Cuz I am not getting down there over and over. Call me lazy, but its only 79.99 extra for it.
My exhaust is the slp loudmouth plumbing with a dynomax resonator. I will not change it. It's a neat sound that I am not willing to part with.
Well, those gains seem to be pretty significant at times. Not sure why tally didnt gain anything. Maybe 7 lbs on the D1 was not enough pressure to really notice. Thats strange that it would not even gain 1hp though.
