408 LS3 top end Dyno results
#1
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I have a 2002 camaro m6 stock rear with a 408:
408CID
forged bottom end with wiesco flat tops 3cc valve relifes
10.5:1 compression
EPS 236/242 .629/.629 114+2 LSA
L92 heads with minor port/polish work
LS3 intake (stock)
92mm TB
85mm MAF
SLP flo pack (soon to add an SSRA)
TSP 1 7/8" headers with 3" true duals
On a mustang dyno i made 440whp and 420 wtq
![](http://i1299.photobucket.com/albums/ag72/kingpin1094/358249F1-5E38-4248-9694-9B9065003B89-2824-00000373E6F13DC1_zps0147af87.jpg)
I also took it to the track, and on a 100 degree day ran 12.63 at 117.5.
408CID
forged bottom end with wiesco flat tops 3cc valve relifes
10.5:1 compression
EPS 236/242 .629/.629 114+2 LSA
L92 heads with minor port/polish work
LS3 intake (stock)
92mm TB
85mm MAF
SLP flo pack (soon to add an SSRA)
TSP 1 7/8" headers with 3" true duals
On a mustang dyno i made 440whp and 420 wtq
![](http://i1299.photobucket.com/albums/ag72/kingpin1094/358249F1-5E38-4248-9694-9B9065003B89-2824-00000373E6F13DC1_zps0147af87.jpg)
I also took it to the track, and on a 100 degree day ran 12.63 at 117.5.
#5
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I agree, i expected to see the low ET cause it couldnt hook at all, and would even lose traction in the 1->2 shift some times. But i think i should be able to get 125 out of it. Im gonna go back on a cooler day and see what i can do.
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#11
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I just calculated my DC at 10.3 static compression, and based on my calculations my dynamic compression is at 9:1. From what i understand thats already a bit high. So if i raise my static compression to 11.5:1 then that would only raise my DC higher closer to 10:1 which may cause detonation and the tuner will have to pull timing for it to run right. Any thoughts on this?
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If I were you go back to a cathedral port head and bigger cam I made around this power with my 347ci. IMO I just don't like a ls3 style head on a 408 or smaller but if u were to boost this it'd be fine if you're trying to do something n/a I'd go another route.
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Did you change the valves in the heads? I know the square port heads fit on a 4.030 bore but seems like I read there really wasn't enough room and caused valve shrouding. The shrouding hurts the air flow into the cylinder. That's why some of the companies make small bore ls3 heads.
Also are you sure you have a 92mm TB? Isn't the GM factory intakes 90mm? If you have a 92mm TB then your air flow into the intake could be messed up.
Also are you sure you have a 92mm TB? Isn't the GM factory intakes 90mm? If you have a 92mm TB then your air flow into the intake could be messed up.
#15
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Did you change the valves in the heads? I know the square port heads fit on a 4.030 bore but seems like I read there really wasn't enough room and caused valve shrouding. The shrouding hurts the air flow into the cylinder. That's why some of the companies make small bore ls3 heads.
Also are you sure you have a 92mm TB? Isn't the GM factory intakes 90mm? If you have a 92mm TB then your air flow into the intake could be messed up.
Also are you sure you have a 92mm TB? Isn't the GM factory intakes 90mm? If you have a 92mm TB then your air flow into the intake could be messed up.
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i made 465/432 with stock bottom lq4 at 10.5 comp, 230/238, stock ls3 heads, stock l92 intake, 1 7/8 lt, 92 tb, 6spd w/ 4.10s. this was on a dynojet but should be right with you on a md. I think your cam is installed wrong or the tune is off. Something is deff wrong but its not the heads/intake. Im only on a 4.0 bore so your 4.030 is also not the problem.