Dynoed my 408..
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Joined: May 2003
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From: Cincinnati, OH
Dynoed my 408.. Well I got my 408 dynoed and I thought that it would make a little more power than it did. It made 445rwhp and 518rwtq. The torque seems fine, but I thought that the horsepower would be more. Is it because it is an A4 w/ a big stall? Let me know what you guys think. Mods are listed below
Stage 3 LS1 heads w/ 2.08 1.60 valves, 225 cc intake runners and 84 cc exh.
11.3:1 compression
.608 .612 240 244 112 Comp Cam
LS6 intake
Ported Stock TB
4L60E w/ 4400 stall convertor
Hooker Long tube headers w/ Dynomax Bullet mufflers off the headers
Stock 10 bolt w/ 3.73 gears
36lb injectors
If there is anything else let me know, Thanks
Stage 3 LS1 heads w/ 2.08 1.60 valves, 225 cc intake runners and 84 cc exh.
11.3:1 compression
.608 .612 240 244 112 Comp Cam
LS6 intake
Ported Stock TB
4L60E w/ 4400 stall convertor
Hooker Long tube headers w/ Dynomax Bullet mufflers off the headers
Stock 10 bolt w/ 3.73 gears
36lb injectors
If there is anything else let me know, Thanks
Nice numbers especially the torque! You would probably benefit greatly from a FAST 90mm setup but I would inquire to people w 408's first. BTW That's a beautiful SS you have there. Congrats!
Some of it is definitely due to your stall, but a few items you have are less than optimal for a 408. You would really really really benefit grom a 90mm intake and TB, probably an easy 15 or 20 rwhp, if not more. The Hooker headers are 1 3/4", you'd probably see 5-15 from a set of 1 7/8" headers. Also, who did the heads? What do they flow?
IMO, with the bigger headers and 90mm stuff, you'd see honest 15-30 rwhp gains. Your numbers are good, and about on par with other big inch A4 cars, it probably hauls ***.
Shawn
IMO, with the bigger headers and 90mm stuff, you'd see honest 15-30 rwhp gains. Your numbers are good, and about on par with other big inch A4 cars, it probably hauls ***.
Shawn
Last edited by SPANKY LS1; Feb 27, 2005 at 08:01 PM.
Are your converters locked??? My 383 made 460rwhp and 432rwtq with a 4400 stall and a 12 bolt with 4.11 gears. Ia m expecting 500/500 in the power department at least with the 408 I am building
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Thread Starter
TECH Apprentice
iTrader: (3)
Joined: May 2003
Posts: 305
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From: Cincinnati, OH
CNC Cylinder Heads in florida did the heads, I am not sure exactly what they flow, As far as the convertor goes I don't think it was locked up either. Thanks for the compliments on the car too.
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nice ride...the paint looks great!!
um, how long have you had the motor in? I ask because i've seen a 408 (m6 though) dyno 502hp and later do 537hp. ALso, your cam seems a tad small. Not by much though. Im running a 246/248 @6xx/61x lift....
here check this out...my APE motor on an engine dyno made 591hp, with 1 3/4 headers, ls6 manifold and stock tb. It has a set of stage 3 heads (APE race heads: lq9 2.08/1.60), and a comp cam @ 246/248 60x/61x lift 114lsa.
With my auto, i have a ss3600 stall and a stock rear. Lets go nuts and take away a 20% drivetrain loss. form 591hp we get 472.8hp..... The point is that either a you probably need to recalibrate your tune or (and i know you would probably hate to open her up again..) go to a larger cam..but not much.
Personally, i think your numbers look great and its not necesarily peak numbers but how early that torque straightened out. With your auto, numbers are gonna be less but will still destroy a similar car with stock cubes and same hp. With the fast 90/90, you should see some nice gains but i would stay with the 1 3/4 headers.....if anything get a cutout....your not gonna see that much more of a hp/trq. difference with a larger header.
dont worry though, with that kind of power you should see 120mph+ trap speeds which is good for 11'z easy or 10'z..... if you get bored...well you can always drop the CR and go boost or hit it with some magic salsa!!!'
good luck!!
um, how long have you had the motor in? I ask because i've seen a 408 (m6 though) dyno 502hp and later do 537hp. ALso, your cam seems a tad small. Not by much though. Im running a 246/248 @6xx/61x lift....
here check this out...my APE motor on an engine dyno made 591hp, with 1 3/4 headers, ls6 manifold and stock tb. It has a set of stage 3 heads (APE race heads: lq9 2.08/1.60), and a comp cam @ 246/248 60x/61x lift 114lsa.
With my auto, i have a ss3600 stall and a stock rear. Lets go nuts and take away a 20% drivetrain loss. form 591hp we get 472.8hp..... The point is that either a you probably need to recalibrate your tune or (and i know you would probably hate to open her up again..) go to a larger cam..but not much.
Personally, i think your numbers look great and its not necesarily peak numbers but how early that torque straightened out. With your auto, numbers are gonna be less but will still destroy a similar car with stock cubes and same hp. With the fast 90/90, you should see some nice gains but i would stay with the 1 3/4 headers.....if anything get a cutout....your not gonna see that much more of a hp/trq. difference with a larger header.
dont worry though, with that kind of power you should see 120mph+ trap speeds which is good for 11'z easy or 10'z..... if you get bored...well you can always drop the CR and go boost or hit it with some magic salsa!!!'
good luck!!
Originally Posted by 98CustomSS
Well I got my 408 dynoed and I thought that it would make a little more power than it did. It made 445rwhp and 518rwtq. The torque seems fine, but I thought that the horsepower would be more. Is it because it is an A4 w/ a big stall? Let me know what you guys think. Mods are listed below
Stage 3 LS1 heads w/ 2.08 1.60 valves, 225 cc intake runners and 84 cc exh.
11.3:1 compression
.608 .612 240 244 112 Comp Cam
LS6 intake
Ported Stock TB
4L60E w/ 4400 stall convertor
Hooker Long tube headers w/ Dynomax Bullet mufflers off the headers
Stock 10 bolt w/ 3.73 gears
36lb injectors
If there is anything else let me know, Thanks
Stage 3 LS1 heads w/ 2.08 1.60 valves, 225 cc intake runners and 84 cc exh.
11.3:1 compression
.608 .612 240 244 112 Comp Cam
LS6 intake
Ported Stock TB
4L60E w/ 4400 stall convertor
Hooker Long tube headers w/ Dynomax Bullet mufflers off the headers
Stock 10 bolt w/ 3.73 gears
36lb injectors
If there is anything else let me know, Thanks
With those numbers and good traction, it should be no problem to run mid to low 11's. Depending on how aggresive your suspension setup is and how much the car weighs it might be possible to see a high 10 with the Fast 90/90 setup on a cool night.
***Beautiful paintjob! Its my desktop wallpaper on my PC at home.
Jeff
TECH Fanatic
Joined: Sep 2002
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From: -TeXaS-?
my 427 made 447 rwhp and 450 tq through the 12 bolt and 4L60E. Locked the converter and it made 498 RWHP and 490 RWTQ. That was on 22 degrees of timing tuned for a 250 shot.
Those are stout #'s IMO.
Those are stout #'s IMO.
Originally Posted by SNAXS
my 427 made 447 rwhp and 450 tq through the 12 bolt and 4L60E. Locked the converter and it made 498 RWHP and 490 RWTQ. That was on 22 degrees of timing tuned for a 250 shot.
Those are stout #'s IMO.
Those are stout #'s IMO.
Great looking paint job! Don't get hung up on dyno numbers. I've never seen anyone race on a dyno yet. My car only makes 508 rwhp and I'm not doing to bad with my ET. Enjoy that new motor, sounds like an awesome whip you got there.
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From: -TeXaS-?
Originally Posted by 2001 Pewter WS6
Those numbers don't seem right. How can you make more torque with the converter locked than it did with it unlocked
Originally Posted by SNAXS
Ill see if I can find the graph and post it up but thats what it dynoed if I remember correctly.
The numbers don't seem bad for the heads that are on it. I've never seen anything spectacular from CNC in Florida. Really I've been unimpressed with every car I have seen with there heads. Get the parts that are mentioned and you should pick up a good bit.
