Disapointed in Dyno #s 408
Disapointed in Dyno #s 408 Mods in sig, finally got a dyno tune today, 455/455. I'm disapointed. Trust me the car is super fun to drive and a hand full, but from what I've seen here I expected at least 470. I was hoping for 490+.
Here's the story, couple things hurting HP:
My 342 rear was bad so I dropped in my 323. I've already ordered 373s.
My CNC Patriot2 heads?
Cam?
Unported 92 Fast
Hooker LTs 1 3/4s I think, non super comp. Thinking of TSP 1 7/8 LTs
I reached peak HP at 5800, a little flat to 6300. I'm ok with that don't want to rev to the moon, though I think it should still pull to 6300. Springs are the double HD good to .650.
Next week I'll have the new gears in.
I've considered ported L92s or Ls7s or more porting on the 243 Ls6 heads.
Fuel is good and timing was 33 max at WOT. AF was 12.5-12.7
Think it may be a combination of needing a custom cam, porting fast 92 and hooker LTs. This all may add up to 50 HP I'm missing...
My goal is 500 NA. So Those ported L92s and LSX int with 1 7/8 LTs should put me into the 500na range.
Here's the story, couple things hurting HP:
My 342 rear was bad so I dropped in my 323. I've already ordered 373s.
My CNC Patriot2 heads?
Cam?
Unported 92 Fast
Hooker LTs 1 3/4s I think, non super comp. Thinking of TSP 1 7/8 LTs
I reached peak HP at 5800, a little flat to 6300. I'm ok with that don't want to rev to the moon, though I think it should still pull to 6300. Springs are the double HD good to .650.
Next week I'll have the new gears in.
I've considered ported L92s or Ls7s or more porting on the 243 Ls6 heads.
Fuel is good and timing was 33 max at WOT. AF was 12.5-12.7
Think it may be a combination of needing a custom cam, porting fast 92 and hooker LTs. This all may add up to 50 HP I'm missing...
My goal is 500 NA. So Those ported L92s and LSX int with 1 7/8 LTs should put me into the 500na range.
Last edited by RyanSws6; Jul 11, 2009 at 07:18 PM.
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From: Bryant/Fayetteville, Arkansas
Some larger primaries will open up some constricted horsepower, but not to the level youre wanting. Other factors come into play on that, hopefully someone who knows more than me will chime in on that.
Yeah been thinking that...I got those heads when I was planing a Ls6 build.
I just got the GM high tech issue with the section on 4.0 bore heads. I may do this along with the 1 7/8 headers.
I just got the GM high tech issue with the section on 4.0 bore heads. I may do this along with the 1 7/8 headers.
Take it to the track....
Dyno numbers mean very little due to so many variances in dynos and other factors....
The track for the most part will give you a much better idea of how your car performs
Dyno numbers mean very little due to so many variances in dynos and other factors....
The track for the most part will give you a much better idea of how your car performs
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Verdad Gallardo Not looking for a dyno queen. But my goal for this build was 500NA. I think you guys can understand that. I've been reading how dynos give different #s. Trying not to focus on the #s but hard not to when I didn't hit my goal.
Now need to decide if to rework the CNC Ls6 heads
OR
Buy AFRs or Trick flows
OR
Go Ls3/L92
Now need to decide if to rework the CNC Ls6 heads
OR
Buy AFRs or Trick flows
OR
Go Ls3/L92
[QUOTE=RyanSws6;11895943]Not looking for a dyno queen. But my goal for this build was 500NA. I think you guys can understand that. I've been reading how dynos give different #s. Trying not to focus on the #s but hard not to when I didn't hit my goal.
Now need to decide if to rework the CNC Ls6 heads
OR
>Buy AFRs or Trick flows<
Get the AFR's or TFS heads, port your FAST 92 and TB and you'll pick up that extra power you are looking for.
Jimbo
Now need to decide if to rework the CNC Ls6 heads
OR
>Buy AFRs or Trick flows<
Get the AFR's or TFS heads, port your FAST 92 and TB and you'll pick up that extra power you are looking for.
Jimbo
Try lowering your timing if you have 243 heads. They make best power around 22-26 degrees of total timing. If you did the L92 heads you would need a different cam as they work better with a lot smaller cam. What is your compression ratio and was the cam degree'd to the specified valve events?
I have a friend with 408ci Gained almost 15rwhp in mid range and peak power from swapping a cam very similer to your to PatG Custom grind and after that he changed his 1.3/4 LT Headers to Kooks 1.7/8 Headers
Numbers were Like this 1st Run a4 408ci Similer cam and Patriot Stg 3 heads
made 466rwhp
Patg Cam with M6 Swap made 495rwhp
final numbers with PatG Cam, M6, Stg 3 Patriot Heads, Kooks 1.7/8 headers
a great 505rwhp 475rwtq
Get TSP Thire awesome , Talk to Pat about a cam, port your Intake
(talk to Ron@vengeance) and if you can change the heads
thats 500+rwhp setup right there for sure and BTW Your numbers are not that abd for the setup.
can you post a graph??
Numbers were Like this 1st Run a4 408ci Similer cam and Patriot Stg 3 heads
made 466rwhp
Patg Cam with M6 Swap made 495rwhp
final numbers with PatG Cam, M6, Stg 3 Patriot Heads, Kooks 1.7/8 headers
a great 505rwhp 475rwtq
Get TSP Thire awesome , Talk to Pat about a cam, port your Intake
(talk to Ron@vengeance) and if you can change the heads
thats 500+rwhp setup right there for sure and BTW Your numbers are not that abd for the setup.
can you post a graph??
TECH Senior Member
Joined: Mar 2004
Posts: 14,620
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From: BFE
I know how to make $$ in the US. Run a happy dyno, that is all poeple care about.
You see nothing in a dyno graph but the peak number
>I do not see a Ram air, if you are only running lid you are choking.
>1 7/8 headers, 10 or maybe 15rwhp
> cam is good, but if it peaks that early, degree it and retard it 2>4*
>what exhaust do you have? if Y pipe run cutout.
That should get you 30rwhp
You see nothing in a dyno graph but the peak number
>I do not see a Ram air, if you are only running lid you are choking.
>1 7/8 headers, 10 or maybe 15rwhp
> cam is good, but if it peaks that early, degree it and retard it 2>4*
>what exhaust do you have? if Y pipe run cutout.
That should get you 30rwhp
TECH Resident
Joined: Jul 2006
Posts: 840
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From: SE OHIO
WORD 
For a cam that size to peak at 5800rpm, I'd start by rechecking the intake centerline it was installed at. That seems a good bit early (again, without knowing full details on the cam spec and VE's). And then get the rest of the combo up to par like the heads, intake, exhaust so the engine can breath in and out efficiently.
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Matt, the cam I had ordered from John at the same time I ordered the 408. I will be ordering the 1 7/8 headers you guys have.
The peak is way too early. I don't think my tunner played with the timing much as we did 3 pulls.
I've been in several 500rwhp cars I saw on the dyno and went for a ride. I know exactly what I want NA.
It is a ram air with OE box, hood and SLP lid.
I want to get the 92 fast ported any recomendations?
Looking into this now...
Will install a cutout prior to the Y.
TSP 1 7/8 headers
Porting Fast 92
Further research: HEADS, AFR or TFS or reworking the Patriot 2s.
Catback is similar to my Borla on my LT1. Hooker Y into a resonator straight out the rear, then like in the borla SLP 2OTL. Sound is perfect! No rasp.
The peak is way too early. I don't think my tunner played with the timing much as we did 3 pulls.
I've been in several 500rwhp cars I saw on the dyno and went for a ride. I know exactly what I want NA.
It is a ram air with OE box, hood and SLP lid.
I want to get the 92 fast ported any recomendations?
Looking into this now...
Will install a cutout prior to the Y.
TSP 1 7/8 headers
Porting Fast 92
Further research: HEADS, AFR or TFS or reworking the Patriot 2s.
Catback is similar to my Borla on my LT1. Hooker Y into a resonator straight out the rear, then like in the borla SLP 2OTL. Sound is perfect! No rasp.
buy some heads that flow 320-340 maybe tfs 235's or etp 245's but patriot stage III's and a 24x-25x cam should be in the 500+ and with 1 7/8 i think 10-15 is what they will net you if you go true duals
Thanks, I just ordered the 1 7/8 headers and sold the Hookers. Now I'm working on the heads. From what I've been reading the cam I have should still net 500. Looking at bumping up compression from 10.2 to 11.5-8.
......that and slow down the tach. If you don't have that much faith in your machinist is it worth the $1 savings?
To make HP NA, you need RPM, thats all you got.