allngn_c5

iTrader: (3)

Updated chart
346 - afr 205 (59cc), g6x3 cam, ported FAST 90, ported NW 90 tb, ewp, ud pully, lg pros (no cats), bullets and VaraRam w/K&N .040 cometic head gaskets, 30# inj's

402 - afr 205 (58cc), g6x3 cam, ported FAST 92 from Vengeance racing that is opened to 95mm, Rev Xtreme 95mm tb, EWP, UD Pully, LG Pros (no cats), LG Big 3, VaraRam w/K&N .051 or .056 gm mls head gaskets, 42# inj's

346 rwhp rwtq 402 rwhp rwtq GAINS rwhp rwtq
3000 210 360 3000 240 420 +30 +60
3500 240 370 3500 300 460 +60 +70
4000 300 395 4000 375 485 +75 +90
4500 370 430 4500 440 510 +70 +80
5000 420 440 5000 480 500 +60 +60
5500 450 430 5500 500 475 +50 +45
6000 475 415 6000 515 455 +35 +40
6500 480 395 6500 505 410 +25 +15

So as you can see here the 346 with basically the same parts as the 402 doesn't even compare. That is unless you wanted to spin these motors to 7500 rpms. Had I planned on spinning the 402 to 7500 rpms, I'd have opted for a better flowing head because it was a foregone conclusion that as the RPMS came up the 402 would move a lot more air then the 346 and would need to breathe better up top then what the milled afr 205's would allow. You have to admit though, the 346 was coming on strong and had we pushed to higher rpms I believe the 346 would've made more hp/tq at 7500, perhaps as early as 7000 rpms. Only due to the heads inability to flow enough air in the 7000-7500 rpm range on a 402. Doesn't matter though, the afr 205's did their job on the 402 better then expected, and I couldn't be happier with the results.

Just can't wait to drive it.

2FNQUIK

iTrader: (17)

Nice numbers/comparison..did you go with a stroker kit or a completely new assembled 402 shortblock

Beaflag VonRathburg

iTrader: (176)

I love seeing results like this. This is a perfect example of when people try to compare stock cube to stroker setups.

allngn_c5

iTrader: (3)

LS2 block, with a callies forged crank, compstar rods, and mahle -12 cc pistons. All work done by LG Motorsports. Machining, assembly, install, and tuning.

allngn_c5

iTrader: (3)

Just trying to help out. Same car, same dyno, only differences are different day and more cubic inches. LOL. Should be pretty consistent.

jmill96Z

iTrader: (3)

So same guts huh? I like this comparison. I always wonder what would happen if I went 402/408 on a serious budget re-using heads and cam. Very cool.

allngn_c5

iTrader: (3)

No not same guts. New forged internal. Callies and Mahle in an aluminum ls2.

jmill96Z

iTrader: (3)

Meh, you know what I mean. LOL I am thinking of picking up a budget 408, but can't really swing new heads/cam right now. Glad to see there are still solid gains to be had.

allngn_c5

iTrader: (3)

Sorry bro, yes its the same "guts" meaning same h/c from 346 was reused in the 402.

Cgillies86

iTrader: (1)

Here is a graphical representation of his power/torque:

allngn_c5

iTrader: (3)

Hey Chris, long time no see you on tech. You must be taking a break from your studies. Thanks for punching in the data. I already had an overlay from LG but it was 402 vs 346 before the 95mm tb swap and tune tweaked and as you know the 95mm tb really strengthened the mid range. At any rate the graph you did really shows how fat the 402 is under the curve. Lots of torque, and makes a ton of power sooner then the 346 does.

BTW, its looking like I am going to try and fly down on the 24th. Gotta get my time off from work approved. Also hope the last 17 seats don't sell out between now and Monday afternoon.

STAY TUNED ..........................

sixpack_2_go

iTrader: (1)

GREAT THREAD!!!!!! i have been on ls1tech for 3 years now. i have read many great threads but, this is one of the best i have seen.
this is an awsome side by side comparison of effect of bigger cubic inch with no major change in other parts.
also, very well displayed with side by side hp/tq comparison in each rpm.

just out of curiosity, i would interested to see any 383 vs. 402 comparisons with the same head and cam setup. that would be good read too.

allngn_c5

iTrader: (3)

Thanks for the huge compliment.

You wouldn't believe how many Pm's and emails I get asking me questions about how much power I picked up. I thought the chart would better illustrate it then the graph does. A line is nice, but actual numbers seem to be better.

ExceSSive

iTrader: (13)

It all depends if the person looking likes numbers or pictures better. The graph says alot...but the numbers give it value.

BlkBird2000

iTrader: (10)

You have not drove it yet? I'd be going crazy!! Good thread.

382ssz28

iTrader: (24)

Good job, Doug!! Wish I would have done that with my 346-382. I only have the increase in 1/8th mile times. Cubes Rule! Next motor will be BIG!

allngn_c5

iTrader: (3)

Thanks Brian. Coming from you I take it as a real compliment. We've talked and you know your stuff. I wish I knew 1% of what you do about cars, if I did I'd be running a shop. LOL. HINT HINT

allngn_c5

iTrader: (3)

The swap from the 90 mm to the 95mm really helped fatten up the power difference from 3500-5000 rpms. Who wouldn't want to be +60 to 75 rwhp and +60 to 90 rwtq ??? As long as she has traction its a done deal. Should be a lot more fun to drive too, considering all the new lowend power. Cmon 3/24, time to go get this thing.

Moonder

Nice, What is the CR in the 402 ?

allngn_c5

iTrader: (3)

Low 11 to 1 compression. Can't remember exactly, I want to say 11.3 to 1 or 11.1 to 1.

Maybe this will help -12cc pistons, afr 205's w/58cc, gm mls gasket .056 ? What else do you need for the equation.