Details: 408LQ4 Mahle -12cc dish pistons (.018 -.020 above deck), 10.93:1 SCR,
PRC Stg 2 Ls6 heads, 64cc chambers .660 dual springs,
kooks 1.75" LTs,
LTD True Duals w/ DynoMax Race Bullets
Catless, 42lb green top SVO injectors
gm mls .055 headgasket
Scat 6.125 rods
Scat 4" crank
242/246 .613 .614 113 + 2
Ls7 Lifters
Tsp Oil pump
Asp 25% UD
Monster Stg 3 Clutch and flywheel kit
moser 12bolt 4:10s
Fast 90/90
Volant Twin cone Fbody CAI
85mm Maf (76mm Maf used after 85mm Failed out during 2nd Dyno Run)
Steel DS

Car is a 2002 M6 WS6, dynoed on a dynojet 248h. Dyno is a bit tough, G6x3 cam, 1.875" Kooks, o/r xpipe, Ud pulley, fast 102, cold air induction CAI, M6 2010 LS3 Camaro put down 483/445wtq on same dyno.

Not My car, but a friend of mines. (Might chime in) I did not tune the car was just reviewing the graphs and logs. Also have the HPT file.

Graph looks smooth and power looks good Just not as high as expected

Car was tuned at Dynosport (About 600+ miles on engine)

Best pull was made with 23* of timing, Pull with 444whp was with 28*

 

Torque looks decent for your setup , but i would have expected more hp, heads and intake are probably hurting u a bit . Bigger intake like a fast 102 and at least a trickflow 225 would definently get u closer to the 500 mark

 

Just wondering why numbers are soo far down from a similar setup like this one:

https://ls1tech.com/forums/dynamomet...cesetters.html

With a stock LS6, Pacesetters, Stock 241s, and damn Near same cam, compression. Biggest difference is pistons

 

You think swapping to TFS 225s and Fast 102 over the Fast 90 and PRC CNC LS6 heads are worth 40whp or more????

 

I would think it would make 40+ more than it did.
There are no misfires or knock?
How many miles are on the 408?

Maybe try a Speed Density Tune instead.

 

over 650 miles on the motor. No Knock at 23 or 28*

No misfires

AFR looks in line and was measured at the exhaust tip with standard DYNOJET Sniffer

 

If u decide to go to a different set of heads , go ahead and get a custom cam ground for the heads and your setup....I also agree on the SD tune, lose the maf

 

Can you post the log files?

 

Only had some still images of the log. The tuner didnt save the full scans

 

mill the heads .030 ull still clear PtoV, u have pretty low compression for the setup u have. it should easily clear 520 rwhp

 

Dont think the intake will seal up since the block has been decked .020 - .030, but I could be wrong......

 

heads are killing it and maf didnt help

 

tried the 85mm MAF before it failed out. Made 440/433

finished tuning it on the 76mm since it still worked

Here it is on the 85mm:

 

Was the cam degreed correctly? Any misfires being recognized? This setup even with those heads should easily be in 470-480 rwhp and 450-470 rwtq IMO. The heads and intake are a restriction, but not nearly enough to equate for the power loss your friend is experiencing.

 

Cam installed dot to dot. its on a 113LSA set on a 111ICL or 113 +2 as per comps final inspection.

 

I dont understand why all the decking on block piston selection and head cc ! Not being a *** just curious why you did it this way ! That is a **** load to be stickig out the block ! I seen them set low ! And seen them .008 out never that far though!
I mean is there a point where to much isnt od ?
valve angle and geomtry intake not fitting?
I am just asking is all and i get 11.35 on compression

 

its close on # if you ask me ! rear end and maf setup is choke point !

 

Like I posted on LS1GTO, you need to address your entire intake setup along with the headers. Even though the cam and heads are less than ideal, it is still a 408 and still needs to breathe. You need a 4 inch intake tract, meaning 104mm Lid, 100mm MAF (or a 4 inch coupler if you go SD), 102mm TB and intake. Also the 1 7/8s headers will help you out a lot too. The numbers also look pretty dead on to me. You are running parts that would choke a 346 running that heads and cam setup, adding 62 cubic inches will only worsen the losses.

 

I DID NOT DO This BUILD!!

I suggested running the Wiseco K394x3 -8cc piston at 0 deck to .004+. Was told that those pistons were around $150* more for a full set of 8 than the -12cc Dish MAHLE.

When I heard about the piston being run that far out of the hole I suggested NOT to. ******** Engines (Builders for this setup) Stated that they run pistons out of the hole all the time for the race engines and that it would make the car have more power with less timing. They also took a little time to take a dye grinder to the valve reliefs on the BNIB MAHLE pistons to "Knock the edges down to combat hot spots".

My friend wanted Blueprint to do the build, the heads that were used came off of his old LS1/MS3 setup. As well as the Intake, TB, Headers and he wanted to reuse his old stuff to save a few $$. So I wasnt going to argue with him or the builders. They were set in there ways to running the cheaper piston and .020 out of the hole to get better compression without milling the heads.

Only thing I can see different between this build and many others (Some have even used stock 799 heads with smaller cam) is the piston selection and how far the piston is running out of the hole.

For the top end parts used on this car there is NO reason it shouldnt be over 460whp.

FAST 90/90 has been used on multiple 402/408 builds with great results. LS6 heads STOCK have put down better numbers on a mustang dyno on other 408s.

Compairing flow numbers alone take into consideration that the LS6 heads are normally measured on a 3.900" Bore plate while ALOT of other heads are measured on a 4.0" plate.

Still open to suggestions. But for the amount of money being suggested in (FAST 102/100mm MAF/104 Lid/Trickflow,AFR heads/ 1.875" LTs/Retune) you will be looking at over $5K to gain maybe 40-50whp! I would hope a Trickflow 225 or AFR 230 setup with everything else listed would be at least 510-520whp. Guess it means this one is only about 70+whp shy ~~

Its not like he is going from stock LS6 intake/Tb/241's to a Trickflow/FAST/Big Mouth setup. Just my .02cents

Still open to more suggestions


Headed back to the dyno today with a 02 firehawk (PRC 227, SNL V.4 cam, FAST 102/102, FTP 104 Lid, 100mm MAF, SLP 1.75" LTs, STOCK BOTTOM END LS1, Moser 12bolt 3.73's) that a friend and I have been working on for awhile.

(Same Dyno as this 408 was on)

 

Considering that my Forged 347 with ported (NOT CNC'd) stock valved LS6 heads, FAST 92/90, 85mm MAF, 1.875" Lts put down 463/416 on the exact same dyno with the 233/239 .598 .603 113LSA cam. 10.7:1 SCR