The other thread was turning into a flame war, so Im sure this will do the same, BUT Im hoping this can remain civil.

For your diagnostic pleasure....



2002 Z28 - 5,000 miles on the car at time of dyno
M6 transmission
Stock 10-bolt w/ 3.42's
OEM SLP airlid
Free Ram Air mod
ASP Pulley
Jantzer Stage II ported TB
Kooks 1-3/4" race style coated longtubes
Lane's true duals with x-pipe
G5X-3 cam
Patriot LS6 style heads w/ 59cc chambers (11.5:1 CR)


<-Flame Suit On

-Wade

 

good numbers i guess



wasnt the G5X-2 pulling those #'s on stock heads?

 

https://ls1tech.com/forums/dynamometer-results-comparisons/116369-dyno-results-patriot-ls6-style-heads-g5x-3-cam.html

Use that as a reference

 

Whats the highest a heads/cam ls1 has ever dyno'd on that dyno? The highest we've ever had at the place in austin is 424rwhp, and that was high dollar LS6 heads and a healthy cam, through no mufflers and no cats on a Z06. You have to compare against the locals that dyno on the same dyno IMO.

 

Raging motorsports has hit 461 rwhp on ls1 (5.7 Liter) heads. that was 346" and a cam similar to that you ran.

 

We had a 00 FRC Vette with an RPM cam and CNC heads put down 439rwhp/400rwtq on the same dyno.

Cam was MUCH smaller(232/236 .571/.577 112) and they were stage 2 LS1 heads!

 

Were all of these through the same type of exhaust? (Full or cutout open ....etc) .. I would think an open cutout could mean about 20hp difference ...

Crowley

 

Lanes True Duals all the way out the back. We dropped the exhaust at the header and lost 10 throughout the band and peak.

 

where do you stand with the new compression test? maybe i misunderstood the previous posts but has one been conducted since the h/c swap?

 

Dyno #'s look normal to me. Everyone cant have HIGH dyno #'s.

 

i say take it to the track and get a time. if it runs high 11s or low 12s then something is wrong but if it does a good time then dont worry about it.

 

Theres a problem. Look how fast the power drops. 20 hp in a matter of a few hundred RPM.

it should carry the peak a lot more than what it did.

 

Ditto, the few X3 dynos I've seen have carried (barely lost) any power up to 7k.....

Shawn

 

torque is down 30 ft lbs to from what I have seen, maybe try another dyno, but if putting on the heads loss power over the last set of stg1 heads you said from the last post, than I would say maybe the heads are not up to the level of others, PDD only did 386rwhp with the pp ls6 heads and tr224 cam, dont understand how 2 other cars did over 440 unless they were ringer cars, well have to wait and see other results with the same heads

 

The X-3 is not that much bigger.

 

I believe Chris is going to dyno it at LG sometime soon. The heads have been on many different cars, in many different states, on many different dynos. They HAVE performed, or Chris wouldnt have bought them.

Everyone around here says that our dyno is about 5-7 hp low(give or take) but definetly not 20.

 

I totally agree. We have a customer that recently dynoed 422 RWHP with the Patriot stage II 5.3L cylinder heads and our 224R camshaft. This was not on our dyno, FYI. The heads have proven themselves, and so has LG's cam. It's possible that there's a "gremlin" to be worked out of the setup.

Trevor
Texas Speed & Performance

 

I'm still voting for the SLP OEM AIRLID as where the problem is.

If I'm wrong oh well, but on my H/C I gained 12rwhp and 6-9rwtq by just switching from the SLP Aftermarket Airlid and I've seen the OEM Blackwing piece, I know it's big but it does have a really small oval-shaped neck.

 

But would changing the lid yield a 20 hp gain?

TTT

 

OK, since the kids ruined the last thread I'd like to get back to the topic at hand. It appears as though the main questions left are either:

rocker arm geometry and/or engine compression

I will contact LG and then we can check both over there and then redyno with a retune if necessary afterwards to see if in fact this is causing a power deficit. I'll post the new results regardless of how much different they are or aren't. Right now the car doesn't feel like it should and I will eliminate every variable and figure out exactly what's up.

Again, I'm not trying to bash anyone here and if the heads are performing they will dyno 450rwhp after the resolution of any possible geometry or compression issues. I'll change the lid just because that is easy and it will eliminate any doubts out there about the SLP piece.

Stay tuned because we just did 3 more cars all with the same heads and all used stock lifters so this shouldn't be an issue with them. I'm curious to see more results myself so time will tell

Chris