LS engine builders - referrals welcome

[AK47SS]

Hi looking at building a LS7 (427) with a 2.9L whipple, who is recommended builder and why?

If anyone has this set up what RWHP are you getting ?

[71RS/SS396]

What is your intended use for the car? The 2.9 intercooler in not very efficient and will heat soak very quickly. The LS7 block is not a wise choice for boost they have very thin cylinder walls, if you want a boosted 427 I would start with the RHS block, it's much stronger than the factory block and has priority main oiling.

[AK47SS]

Many thanks for that, it's only for street use, il consider the RHS , is it heavier?

[71RS/SS396]

Many thanks for that, it's only for street use, il consider the RHS , is it heavier?
I've never actually weighed one vs the LS7, I would guess maybe slightly heavier but I don't think it would matter much if you're bolting a heavy blower on top.

[jwcarguy]

Many thanks for that, it's only for street use, il consider the RHS , is it heavier?

Consider what Tim said!
Also, the weight of the block shouldn't be a factor over strength in a boosted application

Just for refernce:
stock GM "LS" aluminum blocks compared to their "Vortec" counterpart iron blocks is only approx a 75lb. difference

And and good builder (ones that I deal with also) usually recommend a GM iron block or quality aftermarket one as Tim suggested, when dealing in boosted applications

If you want to read up on a bunch of stock LS7 block failures under boost, head over to the Corvette forums and grab a drink, you'll be there awhile!

Not saying that there are boosted aluminum blocks out there (ie alot of Gen5's running s/c's)

plus it depends on, as asked, intended usage, boost level and as always Budget!!