TXNC5

We have started testing some different 402 combinations. Here is a brief description of the results so far:

SDPC 402 using GM Performance Parts LS2 block (Part # 12568950), Callies 4" crank, JE flat top pistons (~11.5:1 CR)

Using GM LS6 CNC Heads (Part # 88958665), a stock LS6 intake, a BBK 80mm TB, and an SDPC Z+ cam - 220/224 @ 0.050 0.551/0.551 lift on a 114 (with 1.7 rockers *** NOTE we were using some custom 1.75 roller rockers, so the lift was actually .567/.567)

With this small cam, HP = 537 @ 5400 and TQ = 564 @ 4600 (almost 500ft/lbs from 3000-6000)

On this setup, we were running a custom vacuum pump. The pump pulled a solid 8-10inHg during the run, and it probably contributed 8-10hp. Unfortunately, the pump broke while tuning our next setup. We expect to have it back in operation for our next round of testing.


We then installed a larger cam, BigStick240 - 240/246 @ .050 .600.600 lift on a 112 (with 1.7 rockers; we were using 1.75 rockers, so our lift was .618/.618).

With this medium cam, HP = 599 @ 6300 and TQ = 572 @ 4800


We then installed a FAST 90 and used a SDPC 90mm TB.

With the FAST 90, HP = 619 @ 6200 and TQ = 582 @ 4800


We have more head/cam combinations to try.


For pics, vids, and more detail, see here.

Florian

Great numbers guys....a quick question though. Why the LS6 intake/heads and not aftermarket>? just curious.


F

TXNC5

The last pull was with a FAST 90. If you check the link in the thread, you will see some of the other stuff that we hope to test. It does include some other heads. We wanted to started with these heads because many people don't realize how good they are.

89lx-ls1

iTrader: (23)

Engine Dyno Correct?

TXNC5

Yes. In fact, there is a vid of a customer's 402 being pulled on the dyno in the link above. It sounds good.

JBT

Great numbers!
What sort of callies crank do you use, racemaster, magnum?
Rods?
How much is that short block?

thinkBIG

Can't see the video at work: Is this engine or chasis dyno?

Edit: Nevermind, I read the thread over.

What do you suppose the results would be to the wheels?

Big-DEN

Was real interesting on these, is that the larger cams lose almost 0 low speed tq and only positive up top. They dont show the graph before 3000 rpm tho. I'm sure the 1000-3000 rpm story a bit different.

Paynful

STP Corrected (J-607)?

MSURacing

iTrader: (1)

I am guessing that it is. No vender would want to report in J-1349 because it is going to be 5% down from eveyone elses numbers
We have to get over the J-607 thing. I think that this is the true aftermarket number because if you want to, you can lookup almost every post on this board and it will be in J-607.

I think it is time us truth seekers give up as the aftermarket will never come over to the truth side!!!

TXNC5

I went back and double checked the data, and I don't have anything below 3000. These runs are mostly to see what kind of top end power we can get out of various combinations. I will see about getting some data down that low for comparison. Who wants to live below 3000RPM

TXNC5

The dyno owner/operator says it is SAE. I will triple check, confirm correction factor, conditions, etc.

TXNC5

There are a lot variables to derive the number at the wheels. Intake and exhaust setup as well as automatic vs manual and what driveline components are used. We believe (and as seen/reported by other 402 setups) that 500RWHP is definitely achievable in a very drivable combination.