Yeah... but they spin 8000 to 9000 RPMS, with 15:1 compression, low-tension rings, dry sump oil system, undersized journals, and plenty of race gas.

I don't think there is anything "standard" about those bottom ends other than the casting numbers . Due to the soft piston slugs, and focus on light rotating weight, we'd be lucky to get 40,000 miles on an engine like that in street duty (they rebuild these things AT LEAST once a season, sometimes once per race, when used in race duty... ie. during high RPM operation). Combine this with expensive tricks like narrow-seat contact valve jobs (BAD for the street), ground to the outside edges of the valve seats, etc... even "stock" heads are way beyond the price of AFR's most of us would use for these numbers.

Doesn't NASCAR permit SB2.2 heads?

 

I doubt it. And then if you did do it, its not even an LT1 by then, and with all the money you have spent, you should just switch to a sbc/bbc

 

They rebuild NASCAR engines every race.

The limiting factor on the SUPR motors is the valvetrain. The ramp rates on the cam are so extreme that they require outlandish valvespring pressure. That much pressure destroys valvesprings, valveseats, cam lobes, and, quicker than anything else, cam bearings. You wouldn't get 1000 street miles out of a 670 fwhp SUPR motor. Also, with the low-tension rings, oil consumption would be high. They don't even install dip sticks. As the engine builder says, if you have to check it, you need to change it.

That reminds me of another saying I once heard:
If ya' have to feed it, and ya' can't eat it, you don't need it. [pets]

Mike

 

No kidding... A rocket block with 18* Brodix heads sounds awefully good by then:

4.150" siamesed bores (427ci anyone?), priority main-bearing oiling, larger cam journals (for more RPM stability), raised cam journals (for more stroke), 4-bolt mains, indexed lifter bores, square decked, and available in aluminum and 1 or 2-piece seals.

Cost? on ~$2500 for the block/caps. Considering the work nessesary to machine an LT1/SBC to these specs it almost sounds like a deal... almost.

Use some SB2.2 heads/valvetrain, a dry sump oil system, and other goodies... voila! 700 fwhp NA of course you'd need to convert to HEI, then decide if you want a FAST computer or carb, so it isn't exactly cheap. Est: $12000+.

 

lol... not exacly "street" worthy.

 

Rocket block, schmoket block... it's all Motown now.

 

You're on the right track, but the cost estimate is way low. Figure block and rotating assy at ~$7,500, $3,000 for the valve train, $5,000 for the heads and intake, $4,000 for the engine management and fuel system (assuming EFI) and a few thousand for odds n' ends like the exhaust system, fasteners, gaskets, etc. and you up to close to $25,000. Then you have to get all the supporting components. Not a cheap project and it still wouldn't be streetable.

700 streetable rwhp from a SBC running on pump gas = forced induction, no two ways about it.

Rich Krause

 

I would have to agree. going to be hard as hell to get that number. I still think Jimlabs is a little low on Drive train loss but not by much. I am sure it will scream but I think it is going to take a little longer then expected to fully dail in. I would love to hook up and see it as I work less then five miles from him.

There are a few of us that are planning big HP Engines around here. None of us plan on going over 600RWHP with out a power adder. We are all planning on being close

It takes ALOT of money and alot of time and effort. Look how long it has taken JimLab to get his engine done and now doing the installation. Every thing is Custom and cost more.

Good luck or your project.

 

R u in denver? if you ever needed any work i know ray is always looking. i got lucking in how i met him. i am good friends with the owner of lakewood muffler and brake, who knew ray.

does it really make that kind of difference from the bottom?

also to correct a mistake, it was 620 dyno. it had been awhile and not quite sure how i got the numbers mixed. as for the z being on the bottle? nope. we are talking about putting n2o in his car after mine. mine is the first car ray has dealt with that has had nitrous. anyways, why argue over what is and what is not possible? the dyno will tell all.

i guess while we are going over stuff being done to the car. ray has been going nutz about me getting a cage and 5pt restraints for safty. he said hed install it all for free if i bought it. do any of you have a 4pt cage and 5pt restraints intalled? have pics? thx as always, drew

 

So now it's down to 620 RWHP? Let me know when it gets down to 520. With LTx heads, that's a lot closer to the realm of believability.

 

The BMR K-member and Hooker LT's make a HUGE difference when working on the car from the bottom. I can reach up and grab the #6 and #8 spark plugs with my fist. Before, I couldn't even see them.

The motor mount bolts are very easy to get to, as are the oil pan bolts.

Mike

 

Hey, where's UB and Big Show when you need them. Someone said you'd need the best 23* heads available, and I'd wager them to be it. We all know that peak numbers don't mean everything, and by the looks of those heads low and mid lift, I'd expect at least 75hp more from a set of C3s on JimLabs setup. Make sense to anyone else? Ok, so noone actually HAS a set of these heads. All the pics UB has are photochopped. LOL j/k.

SUPPOSEDLY, MM&FF is going to test a set in the next couple months on a mustang. Will be nice to see what they finally dyno.

I know this isn't directly in this topic, but alot of people in the other one posted here too, about intake port size. Why do you guys think 225 is too big for a street app? My friend is building a SBF 436 CID stroker with AFR 225s, solid roller, Kooks headers, etc. We figure it should be good for at least 520 rwhp. Probably more, but its not gonna go past 6200 cause it has 3in mains. We'll see.

 

no not to 520. well it will be around that in denver, but im building the car for sea level when i move back to cali. so scrifice hp here for the motor i want there. anyways, like i said before, the dyno will tell.

 

Drew, I think you should get the motor built, in the car, and on the dyno before you start telling everyone what it's going to make... I think you're in for a rude awakening, but that's just my opinion.

 

I'm with Jimlab.

Not to bash you but you need a big wallet to try to get 550rwhp out of a LT1 setup.

No let me correct that, you need a big wallet or a good head to get that kind of power. Mindgame got his power because of what he knew and people he knew, Jimlab paid for the best stuff out there for his motor.

IMHO you are not going to get 1.9-2.0HP per cube, it's just not going to happen on a street driver. 1.8 takes every little trick in the book on a street car in a real streetable RPM range.

Bret