I am contemplating using a built LS1 in a hybrid application and had a few questions. I was wondering what the RPM limitation of the LS1 was. Is it mostly in the valve train or does the lower end need to be beefed up to turn more RPM. Would a head and cam swap with some intake upgrades get me some more revolutions? The body it's going into is old enough that emissions is not a concern so figure on pretty much open exhaust, headers, 3" pipe race mufflers.
Thanks in advance. This is one of the best boards I belong to.
Jon

 

It's both. Rod bolts are a key action item (crank is fine) and valvetrain weight would also help keep rotating mass in check. Stock bottom modified top though peeps are spinning to 6500+ no problem it seems i.e. with large lsa cams like the ls6 which doesn't serve up any power real low.

 

I've got rod bolts in my stock short block and it has seen plenty of 67-6800 rpm shifts. Been 7000 rpm on the dyno a few times too. These motors are pretty stout.

Bruce

 

FYI, The rod bolts in the 2000 and up are a little stronger than 97, 98, and 99. They mention this in the GM parts catolog

 

I've been reading about swapping rod bolts but some people seem to think that new rod bolts affect clamping, not really sure what, but some sort of distorsion of the circle, anybody ever run into an actual problem with this?
Before I drop the engine in, I'd like at address as many issues as possible without spending a fortune. The car I'm swapping into is going to be super light, so power shouldn't be an issue, I'd just like something reliable.
What sort of valve train mods will help out? Besides a head cam swap.

 

are you sure the rod bolts are stronger on the 2000's I thought it was the 01 and 02 f body that had the stronger bolts?

 

Most of the limitations to high RPM in the LS1 are oiling system related as you can make everything else work great. We have turned LS1s over 8000 for short periods drag racing and over 9000 rpm with dry sumps. Any extended time over 7000 I would think you need a dry sump system.

Basically the LS1 shreds and foams the oil as it trys to return to the pan. All the oil drainback from the top of the engine on the LS1 is right on top of the spinning crank therefore the oil gets aerated big time and needs time to settle and let the bubbles go to the top so the pump pickup gets LIQUID oil otherwise you are pumping air which isn't a real good lubricant I've heard!