364 or 402?
#1
Drifting
Thread Starter
364 or 402?
I just picked up an LS2 block for my build. My next step is gathering a few more parts before I drop everything off at RPM Motors.
I originally planned to keep the stock crank and use my LS6 heads and intake but I don't want to regret not going to a 402.
Current mods are ECS Novi 2000, 8 rib, ECS blower cam, 1 3/4 headers, meth, ACT twin clutch, built rear and trans. I will need a fuel system too.
I know it will make plenty of power either way and that the 243 heads and 1 3/4 headers aren't optimal but should I go with a 4" crank or stay stock stroke? The car is a weekend toy that I occasionally drag and some 1/2 mile racing. I'd like to take it to Mojave Mile sometime too.
Opinions appreciated!
I originally planned to keep the stock crank and use my LS6 heads and intake but I don't want to regret not going to a 402.
Current mods are ECS Novi 2000, 8 rib, ECS blower cam, 1 3/4 headers, meth, ACT twin clutch, built rear and trans. I will need a fuel system too.
I know it will make plenty of power either way and that the 243 heads and 1 3/4 headers aren't optimal but should I go with a 4" crank or stay stock stroke? The car is a weekend toy that I occasionally drag and some 1/2 mile racing. I'd like to take it to Mojave Mile sometime too.
Opinions appreciated!
#8
Drifting
Thread Starter
#11
ISIS SUCKS FAT CHOAD
If I were a betting man I'd say that there a few other major reasons that your going to be faster than you were before. decrease in stroke being the least effective of your faster times that you should run.
#12
Le Mans Master
The reason I decided to go 402 was, although most people say the stock crank is good for 1000hp, I was factoring in the strain on the crank from the blower at full load, not to mention mine is an f1r which is known to be very hard to turn...that's likely another 50-60hp worth of strain on the crank and I just wasn't going to take that chance on a $10k motor.. My luck is the one part I don't change is the one that will fail...so for $900 I decided to go to a forged crank for piece of mind...
And since it costs exactly the same to buy a forged 3.62 or 4.0" crank, it seemed to me to have NO down side to going to the 4.0" crank..
Now if I was gonna spin it to 7500 or something I would go stock stroke for sure but.. I just don't see a down side to more cubes if staying at 7k rpms or less..
Plus I figured if I ever pulled the blower off, it would still run decent NA...
And since it costs exactly the same to buy a forged 3.62 or 4.0" crank, it seemed to me to have NO down side to going to the 4.0" crank..
Now if I was gonna spin it to 7500 or something I would go stock stroke for sure but.. I just don't see a down side to more cubes if staying at 7k rpms or less..
Plus I figured if I ever pulled the blower off, it would still run decent NA...
#15
Melting Slicks
Member Since: Jan 2009
Location: Easley/Anderson South Carolina
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From what I found it seems that some say that the piston can rock slightly with a 402/408 setup combined with boost. I could not get 100% certainty with that though.
I decided to go with the stock 365ci over a 402ci, 8.8:1-9.1:1 compression and lots of boost. I figure it will be fast enough.
I decided to go with the stock 365ci over a 402ci, 8.8:1-9.1:1 compression and lots of boost. I figure it will be fast enough.
#16
Safety Car
The 364 is most likely a better motor for a track car, but for the street, the 402 would be more fun.
Thats my opinion atleast.
#17
Race Director
if it were me, with a centrifugal I'd rather have a shorter stroke motor thats higher at higher rpms.
at least in a light weight vette
not to mention the cost savings that can get put elsewhere sticking with a stock crank
at least in a light weight vette
not to mention the cost savings that can get put elsewhere sticking with a stock crank
#18
Drifting
I'd be curious to the gains of doing a solid roller setup at these levels to get all the rpm/powerband you can out of it. At that point you wouldn't want the plastic long runner intakes, etc so it could really bring up the powerband.
#19
Melting Slicks
Member Since: Mar 2008
Location: Houston/Dayton Texas
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On the street you will notice a big difference. 364ci @ 19psi with a YSI still felt super lazy... If we would have went -.200" on the pulley perhaps it would have woken up a bit more. But it felt almost slow even at 900+whp.
The 364 is most likely a better motor for a track car, but for the street, the 402 would be more fun.
Thats my opinion atleast.
The 364 is most likely a better motor for a track car, but for the street, the 402 would be more fun.
Thats my opinion atleast.