BMF_Racing

iTrader: (6)

I know this subject has been addressed over and over again but I was unable to find a thread that matched my questions/setup.

I currently have just the std deck LsX block. This engine will be drag raced only, with no street driving at all. The engine will run on methanol (no intercooler). I really have one goal in mind, make it last a long time. Below are the basic components that I have in mind on ordering.

Forged crank, rods, pistons.
Turbo cam
PRC Ls3 aftermarket 250cc 6-bolt heads
Victor ls3 intake with elbow
235lb Moran injectors (w/appropriate fuel sys)

My goals are to run the engine in the 850 to 1150 whp area for now but leave room in the setup to go higher Hp with a bigger turbo (pt4788 currently) down the road.

I like the idea of more cubes and lower rpms along with the low end Tq added with the 408 over the 370.

I read some say 408s don't last as long due to the a lot of reasons, does that all still apply in a Lsx block? What are everyone's thoughts?

El_Diablo

iTrader: (9)

A solid roller 370 would be gangster..If it's a race motor with no street time why be concerned with low rpm torque? Are you planning on racing a certain class? What's the goal?

BMF_Racing

iTrader: (6)

No specific classes at this time. I my experiences the less you buzz a motor the less wear and lasts longer. To be honest I guess I'm just unsure why 408 is not the way to go (rotating assembly cost the same). I don't want to regret anything if I can with a little more planning. In the past I've always built for 1000 Hp and run it at 500 to 600 Hp and it last forever with no broken parts.

El_Diablo

iTrader: (9)

If you aren't planning to run a class (trying to keep up with a field) build a 408 and have fun. Unless you're wringing it out to run a number it ought to be plenty dependable as long as the tuning is on point.

InsaneDomestics

iTrader: (28)

^^^ x2

BMF_Racing

iTrader: (6)

Ok, if I can still get the power im looking for and rev it to say 6500 (I know that's no much rpm for most), that works for me.

Thanks guys. Just figured I'd ask before I go ordering parts.

ajrothm

No downside to the 4" crank. You can rev them just as high, support the same or more HP and they cost the same.. Really no drawback at all.. No replacement for displacement, even with boost... It will likely leave harder/spool better.

The only argument you will get will be about the pistons with the wrist pin in the oil ring scenario... Lots of people get away with it tho..