how does this build sound?

[boosted]

new to the forum...this site is sweet iv been reading so much on here the past few days

i recently found a lq4 at a junkyard from intake to oil pan for $175 it kept fouling plugs n ran like crap
ill tell you what the plans are...as of right now i drive a s10. i am going to sell it, buy a 99-02 z71 and have the lq4 ready drop in...

ok so now about the motor.
its out of a 2001 or 2002 box van
stripped and hot tanked to be cleaned
stock rods and crank
bored .30 over to make it a 370 to clean the walls up
have new freeze plugs and cam bearings installed
diamond pistons
ls6 cam and yellow valve springs
7.425 pushrods (using stock rockers and lifters)
arp rod bolts and head studs

this motor willl be boosted once in the truck. i am looking for around 10-13 psi.

now some questions i have are...there are a bunch of different pistons...i know i want forged for boost...but there are a lot of dish sizes and what compressions ratio would you recomment?
i know the ls6 cam is not that big but hey its bigger than stock! will those valve springs be ok or would you recommend something a little stiffer? and will the heads be ok stock or what work would you recommend to them. they are stock heads so im guessing their 317s? thanks in advance!!

[boosted]

and by boosted i mean mp70 or 76 turbo..thanks

[CHEVROLADE]

sounds good,ide upgrade the springs though.

[boosted]

what springs would you recommend and can you recommend the pistons id need and cr? they offer a lot off dish sizes...

[Show&Go]

Stay somewhere around stock compression with a lq4. They aren't high compression and they arent low compression either. But if you arent trying to crank the boost to insane levels and have a good tuner it should work out nicely. The heads will work fine. But since you got them off you could clean em up with a little porting and gain a few hp. And +1 on stiffer springs. You dont want valves floating or breaking a spring. Im a fan of patriot dual golds. Ive never had issues and very cost effective... But Im sure others will offer opinions. ALSO i think the van 6.0 is a lil different from a trucks. I read about it somewhere but for the life of me cant remember what the difference is.

[aj06bolt12r]

I would not run that cam. Too small, you will be wanting to swap it out in short order. Call Texas Speed and give them your combo and ask them what to run. Its not that expensive to do it right the first time considering what you are already spending. JMO

[boosted]

can anyone verify if there is a difference in the van lq4s and trucks?

[RedHeartbeat]

No difference that I've ever heard of in all the years they've been putting them in there. Most, if not all, van 6L engines have been set up for 80e transmissions.

[boosted]

what makes them be set up for a 80? is it just the flexplate? and no has yet to say much about the pistons i need to buy. i know keep it at stock cr....but what piston do i need they make so many dishes!!!

with the setup i listed in original post if i get a decent turbo cam, what kinda power numbers can i expect at 10psi?

[RedHeartbeat]

the early models had the longer crank extension on the flywheel side along with the flat flexplate. All later models likely had the spacer and flat flexplate, all with the 80e bolt pattern. I'm not 100% certain on the details but that's my guess.

As for pistons, if you're going to replace them with forged pistons for boost you will need to calculate what CR you want to run to determine what pistons you should get. Remember, the lower the CR the less power the engine is going to make before boost comes up.

To calculate how much power you're going to make the general rule of thumb is that for every 15 PSI of boost you make you double your engine's HP.