L92 heads with a little work would be cheaper than LS7 heads and about as good for a blower motor IMO.

 

I'll leave the light on

Just to clarify: I want to build the car for two different types of events. Plain old Saurday night bracket racing, where consistency and reliability are the key to success. But also have it caopable of running Quick 8 or Quick 16 at various tracks in the region. So, I have been thinking of a blower, turbo, or nitrous setup. Run low boost/no nitrous at the local track on Saturday nights and then crank it up for the occasional Qucik event. Once you start running mid sevens or quicker, it becomes impossible to get the dead-on consistency to win the brackets. And it gets too maintenence intensive to do it week in-week out.

There is a way out of that conundrum I have considered - an NA BBC that is HUGE and therefore not twisted too hard. Kind of the best of both worlds. Launch it easy and shift it early for the brackets and go ***** to the wall for Quick events. But that is old hat and just doesn't interest me. A boosted SB of whatever generation does, but especially the gen III.

Rich

 

900+ HP NA LS7 motor.... I think the tally is over $20K at this point.

 

I still think a turbo LSx would be the coolest.

BTW, I saw you at NYIRP tonight but didn't have time to come say hi.

 

Like the paint job on the 27?? I think it's pretty sweet. Definitely stop by next time.

Rich

 

It looked awesome! I was in the staging lanes when you ran, all I saw was you going from the staging lanes to the burnout box.

I'll stop by for sure next time.

 

511 cubes can be had out of an LSX block. With that displacement, if you only made 1.4HP per cube N/A, (falling off a log), you'd be at 715FWHP. If you split the difference with your supercharger I don't think getting it all done by 7,000rpm's would be entirely out of the question.

Food for thought:

The LS7 gets it's output with a 211/230 .593/.588 camshaft. Guys are seeing 550FWHP with just a longtube header swap. Take away the fuel mileage, emissions, and need to idle with a glass of wine sitting on the intake requirements and it's easily a 650HP cam only motor. Now take that same motor, with the same camshaft that got you to 650HP, and add another 84 cubes to eat up that cam and bring things back down to idling with wineglasses territory: then tweak the heads.

 

A 427 LS7 headed motor in street car form CAN do 650rwhp.

 

So those LS7 heads have some real potential then, huh? Do you think they can adequately support a 500ci motor, or are we going to have to wait for Dart to step up to support this steroid injected version of the "mighty mouse."

 

Well we are using modified ones to support 440cubes up to 8000rpm, but they aren't very efficent up there. I don't really think there is much that can support 500cubes out there yet. They are a very good head imho, and there might be enough room in there to get them to work over 6000rpm with 500cubes but I haven't run any numbers on that yet.

The REAL issue is getting 500cubes, you don't do that cheaply. The LSX in a tall deck version could pull that off, but it's all stroke. Reguarless of what GM says about the LSX sealing 4.250" bores on a 4.400" bore centerline is not a easy task. 4.200" is as far as I would build one on that centerline, that leaves you with a 4.500" stroke and stuffing a small and strong rod in between the bottom of the bores and pan rails.

Bret

 

Damn straight! You get your butt down here and I'll take car of ya. Give me a buzz ahead of time so we can do schedules, but I'm telling ya, the local Pro Mod and King of the Hill racing is top notch. Think maybe $3.00 per gallon has anything to do with that??

OH..... BTW. My wet bar wins everytime. Never been able to beat it yet. Can't say I haven't tried.

 

I've seen actual dyno sheets in the 630 range. Pretty stiff stuff in my book.

 

Yeah I was thinking 4.185 and a 4.5 stroke for a 496 I believe (I could have those numbers wrong). But you're right, I didn't even think about how short that rod would have to be. I guess I could get some custom made though.

So the LS7 heads aren't up to the task then? I guess I will just have to wait for Dart to step up and fill the void once big cube LSx motors really start showing up in racing.

 

Paying with a LS7 head now that could do 6500rpm on 500cubes and maybe go out to 7000rpm but it's going to be pushing it. Anything CAN be done, but you could make more HP per cube by doing it better. Going down 0.2+ hp/cube in a class where you run more lbs per cube ain't a good idea to me.

The biggie is really the intakes attached to the heads.

Denny, BTW that 630rwhp I think will easly do the 650rwhp+ at some point here soon.

Bret

 

Do you like to mess with the individual runner setups with these motors or the conventional style LS intakes? Or some other type of intake?

Are you and OldSStroker going to the 40th celebration in Detroit next month?

Jeremy