After much searching, I am still a bit confused about the capabilities of a boosted LS7. I see a lot of comments stating "It's all in the tune". But at what point is the LS7 with stock internals/sleeves
at risk even with no detonation and a spot-on tune? I am considering the purchase of a SBE C6Z making 800rwhp at a bit less than 6 lbs of boost. Are the cylinder pressures required to produce that
amount of power in excess to what a stock short-block can live with?
Thanks for any insights.
Wayne

 

thin cylinder walls and cylinder pressure is where the problem lies

 

Thanks Russ, much appreciated. So, is that to say the cylinder pressures required for 800whp will be more than the SBE LS7 can tolerate, even with no detonation?
Thanks
Wayne

 

Living on the edge for sure. Could it last a long happy life, maybe. Could it blow up on the way home, maybe.

I wouldn't expect a long life out of a 800rwhp SBE blown ls7, but some people do. All depends on the octane you feed it and duty cycle it deals with. It only makes that power at WOT high RPM, so if the car is just cruised around, not raced, and doesn't see 5k+ besides a dyno once a year, it would live a long happy life. If it is something you plan to take racing every weekend, I would start budgeting a new short block now.

 

Good information. The engine sees a good amount of 100% meth with 93 octane fuel. Going by the YouTube posts, the car sees some fairly aggressive roll pulls up to 160+ mph. The 1/4 mile pulls only produce
traps of ~140mph on what looks like decent driving in decent air. The time-slip splits mirror my passes from a 708whp C5Z so I wonder if the dyno was a bit "happy" and the power level is more in the 730-750 range.
I know driver is a big factor, but my driving pretty much sucked on the passes I compared.
Thanks gain for your input. It looks like you have real world experience with a boosted LS7 as does Russ.
Much appreciated,
Wayne

 

I’d be careful about buying another guys highly modded C6z, there are two I would have considered, a black one recently sold and if the car your speaking of is Nardi’s yellow vette I’d consider that one as well, but 98% I’d say just build it yourself or buy it know a rebuild is is the near future most likely.

a booster LS7 is a damn animal, and a whole lot of fun, but it’s a gamble for sure...especially if you run it hard. I’d at a minimum want a forged piston set up and a refreshed bottom end(that’s what I did and I’ve got a complete rebuild thread on here) now that’s not guaranteeing me anything. I’ve got a great tuner, I run ethanol and meth and have done a lot to help it survive what I put it through....but race cars break man, **** happens.

If you follow Unreal’s build he’s spared no expense and over built, but **** still happens or you could look at Detoxx, dude has ran 700whp-1000whp on a SBE LS3 for like 40k+ miles and his **** is still running hard....it’s just the nature of the game we play unfortunately. I think going into with the mind set to keep a car like that running at peak performance is gonna take cash...a good bit and you’ll be replacing parts way more frequently then others, some things that may last the life of the car are now consumables that’s will just need replacing.


Now with that said, I’ve never not had the biggest child like smile when boost comes on just messing around, and when I’m really driving this thing I’m locked in 100% and get a similar feeling to when I am conducting high risk military training or ops down range. The danger factor is real, and respect is always given...an 800+whp C6z is real rowdy and can get away from you in a hurry! If you’ve lost traction at triple digits I’m sure you know what I’m talking about, if you haven’t....it’s an experience that’s for damn sure.

 

Thanks for the great advice and insights. I think the forum members who have replied have covered the questions I had very well. Thanks to all of you for the help.
Wayne

 

Just to add to this any one throw a number at how much psi the stock head gaskets can typically take?

 

The LS7 pistons seem to be the weak link. Is this the yellow Z06 from Delaware you are talking about? That's an incredibly nice car!

 

Yes, that is the one. That car really is exceptionally well done.
Thanks for the reply,
Wayne

 

Negotiate a few grand off the price and put some pistons in with that. Simple

 

Sleeve failure is pretty common on LS7s and other big bore Aluminum stock blocks.
Even with a great tune, great fuel, its almost inevitable to occur due to thin cylinder walls.
Like unreal mentioned if you plan on just cruising the car and having a little fun here and there it'll probably survive and be fine.