Quest to 400whp!!
Thread Starter
4th Gear
Joined: Oct 2018
Posts: 4
Likes: 0
Quest to 400whp!!
So I’m trying to reach my goal of 400rwhp. Kinda close but yet kinda far at the same time so far my mods are
the car is an AUTO
SLP lid
1 3/4 long tubes
DMH cutout
LS6 intake
mild cam 218/227 .600/.600 lift
PRC stage 2.5 862 heads
36lb injectors
all supporting mods lifters, pushrods, ect.
the car put down 380hp/371tq i don’t thinj these are bad numbers for the build the car does have 125k miles so that has a lot to do with it. Just trying to get to the 400rwhp mark. Please don’t say to swap a different cam or different heads I know a bigger cam would do better but then I’d have to replace the stall in the Trans and everything. Any suggestions on what I could add to get me there any suggestions would be great. I was thinking maybe a under drive pulley? Ported FAST 92/92?
the car is an AUTO
SLP lid
1 3/4 long tubes
DMH cutout
LS6 intake
mild cam 218/227 .600/.600 lift
PRC stage 2.5 862 heads
36lb injectors
all supporting mods lifters, pushrods, ect.
the car put down 380hp/371tq i don’t thinj these are bad numbers for the build the car does have 125k miles so that has a lot to do with it. Just trying to get to the 400rwhp mark. Please don’t say to swap a different cam or different heads I know a bigger cam would do better but then I’d have to replace the stall in the Trans and everything. Any suggestions on what I could add to get me there any suggestions would be great. I was thinking maybe a under drive pulley? Ported FAST 92/92?
Le Mans Master
Joined: Sep 2014
Posts: 5,278
Likes: 539
From: Kelowna BC
How about a cam upgrade? DOH! 
I don't know that much about your cam and heads, but kinda surprised you're not at 400, I guess the auto is sucking that final 20 out.
Seriously doubt an underdrive pulley will do anything near that gain. Maybe the 92?
I don't know that much about your cam and heads, but kinda surprised you're not at 400, I guess the auto is sucking that final 20 out.
Seriously doubt an underdrive pulley will do anything near that gain. Maybe the 92?
Pro
Joined: Jul 2014
Posts: 524
Likes: 48
From: Allenspark Colorado
So I’m trying to reach my goal of 400rwhp. Kinda close but yet kinda far at the same time so far my mods are
the car is an AUTO
SLP lid
1 3/4 long tubes
DMH cutout
LS6 intake
mild cam 218/227 .600/.600 lift
PRC stage 2.5 862 heads
36lb injectors
all supporting mods lifters, pushrods, ect.
the car put down 380hp/371tq i don’t thinj these are bad numbers for the build the car does have 125k miles so that has a lot to do with it. Just trying to get to the 400rwhp mark. Please don’t say to swap a different cam or different heads I know a bigger cam would do better but then I’d have to replace the stall in the Trans and everything. Any suggestions on what I could add to get me there any suggestions would be great. I was thinking maybe a under drive pulley? Ported FAST 92/92?
the car is an AUTO
SLP lid
1 3/4 long tubes
DMH cutout
LS6 intake
mild cam 218/227 .600/.600 lift
PRC stage 2.5 862 heads
36lb injectors
all supporting mods lifters, pushrods, ect.
the car put down 380hp/371tq i don’t thinj these are bad numbers for the build the car does have 125k miles so that has a lot to do with it. Just trying to get to the 400rwhp mark. Please don’t say to swap a different cam or different heads I know a bigger cam would do better but then I’d have to replace the stall in the Trans and everything. Any suggestions on what I could add to get me there any suggestions would be great. I was thinking maybe a under drive pulley? Ported FAST 92/92?
I think a ported FAST will get you close to 400 and if you get rid of cats also you should for sure get there. My headers were cracking so needed replacement anyways, not a cheap upgrade but going catless is cheap! Obviously this isn’t an option for everyone.....
Thread Starter
4th Gear
Joined: Oct 2018
Posts: 4
Likes: 0
it does just a mild cam they call it a “High lift hot cam” because it has a .600/.600 lift. Even the tuner said it should be at 400 I guess I should of also stated that I made the 380hp on the 6th pull and it was a 101 degrees in the building of the dyno. I know someone that put down 632hp at one dyno then went to the same dyno as me and only put down 600hp. So I wanna say maybe the dunk reads low and I probably didn’t pick the best day to get a tune lol
Thread Starter
4th Gear
Joined: Oct 2018
Posts: 4
Likes: 0
when My 6spd had stg 2.5 317 heads, cam (226/228 .600/.600) with 1 3/4” headers, LS6 intake I dynod 405/370. A year later I added ported FAST 90/90 & catless 1 7/8” headers and I dynod 433/396..... a gain of 27 hp and 26 tq.
I think a ported FAST will get you close to 400 and if you get rid of cats also you should for sure get there. My headers were cracking so needed replacement anyways, not a cheap upgrade but going catless is cheap! Obviously this isn’t an option for everyone.....
Pro
Joined: Jul 2014
Posts: 524
Likes: 48
From: Allenspark Colorado
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2020 Corvette of the Year Finalist (performance mods)
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Thread Starter
4th Gear
Joined: Oct 2018
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Pro
Joined: Mar 2004
Posts: 714
Likes: 104
From: Springfield Ohio
Go for the Fast 90 with an LS2 throttle body. It will get you very close. Add a decent CAI, like the Callaway Honker and you should go well over 400 rwhp.
Last edited by tbrowne; Oct 31, 2018 at 01:58 PM. Reason: Fix spelling.
Burning Brakes
Joined: Jan 2007
Posts: 968
Likes: 122
From: Lighthouse Point FL
You need a cam.
I made 440 rwhp on my new LS1 motor and it has an LS6 intake, heads and throttle body. The cam and lifters (and a new short block) took me from 380 to 440. Car has Vararam, long tube headers, mid-pipe and Z06 mufflers. And a 6 speed.
I made 440 rwhp on my new LS1 motor and it has an LS6 intake, heads and throttle body. The cam and lifters (and a new short block) took me from 380 to 440. Car has Vararam, long tube headers, mid-pipe and Z06 mufflers. And a 6 speed.
Last edited by maj75; Oct 31, 2018 at 09:36 AM.