Got a new set of heads

[v8440]

Hi all,

This isn't exactly a progress post, and it doesn't refer to actual work being done to the car...but a couple of days ago I did some trading and ended up with a set of B1 original heads, along with the intake, rockers/shafts, etc. They're used, but fresh from the machine shop. 416 cfm at .700" on the intakes, 2.30/1.81" valves, titanium locks, you get the idea. The shortblock hasn't been built yet, but the block is there. It's a brand new mp megablock. The car is gonna get a small motor first, a single turbo 6 liter gm ls motor. The car is already set up for a smallblock chevy/powerglide, so the 6 liter will go in with a minimum of hassle. Speaking of the car, it's a '71 datsun z. I expect it to weigh about 2500 lbs with me and the big motor, less with the 6 liter. Should move on out pretty decent. Yes, it's going to be a street car. No, your mostly stock mustang will not beat it.

 

[Dr.Jass]

You might have so much fun with that LS you'll forego the big block. The development work on the LSx engines is redunkulous, as is the power they're making with them.

 

[Fishy]

Damn you! I've wanted one of those cars since I was a kid, growing up in Japan. You suck!!

 

[v8440]

True, but a stock block-based ls won't make remotely near the power a turbo'd 572 with B1's will.

 

[Dr.Jass]

One of the guys at work was reading an article online last week about a stock-block 5.3L with a hairdrier and essentially-stock rotating assembly that put out over 1,300HP on the dyno repeatedly. I think it was "Truckin'" magazine. Obviously, a pressure-cooked 572 is nothing to sneeze at, but one must admit that's pretty fargin' impressive.

I forgot that you were going to turbo that engine. The B1s are lovable overkill... totally unnecessary but absolutely grin-worthy.

 

[v8440]

Car craft of one of those did a test where they tried to find the limit of a junkyard 5.3 with over 100,000 miles on it. They put a pair of 76's on it, aftermarket efi'd it, put ported stock heads on it, and put an aftermarket cam in it. Those are the only changes they made, except for re-gapping the stock original compression rings wider to accomodate the boost. They reused the original rings, bearings, and pistons. At 1203 hp it would not take any more boost. It didn't hurt the motor, it just would sputter. They figured it was blowing the spark out, which I think is right. They made over 60 dyno pulls, most at or over 1000 hp, and it survived just fine. Then they got to thinking that it was odd that the 5.3 had flat top pistons instead of dished, so they pulled the oil pan off and looked at the crankshaft. Sure enough, they got ripped off-it was actually a 4.8.

So yeah, I'm familiar with the power potential of a boosted ls motor. But, I've always wanted a big power chrysler big block, I have a brand new megablock, and now a set of B1's. I also have a tube chassis datsun, so the combination is a natural.