FastEddy

Chevy's "fast burn" heads are basically an aluminum version of the vortec head - same design, maybe even same casting - except the fast burn's are set up for larger cams than a stock vortec head. It's common to use the vortec on a performance motor by machining/cutting the head to accept bigger springs for larger lift cams. Stock Vortecs are $400 a pair compared to fastburns at over a $1,000. The 1/2 to full point increase in compression usually run with alum heads may offer a tad more power, and maybe a tad crisper exhaust note - a difference only us HP addicts would notice.....

Another thought:
My car had a stock 327/300 with everything on the motor being cast iron. When I switched to crate motor, not only were the heads now alumn, but also the intake, carb (used edelbrock carb - slight bit lighter than Holley and Carter) and the water pump. The headers were also lighter than the old iron exh. manifolds. It all added up to a good savings - I wish I had weighed all the parts. I ended up cutting a coil off my front stock progressive 64 springs, because the car went from sitting about dead level, to nose high. Final stance was perfect for me. I did weigh whole car, but never before the changes. Car weighed 2960 with half tank and no spare on my local state highway scales.

I believe the common formula is a 10lb reduction in weight equates to 1 horsepower gained for the car.

Realtor-Bob

I am not a speed junkie nor a numbers man (something inbetween). I bought a first gen 383 crate motor from The Enging Shop (found on sleezebay) and got a great deal. Balanced and bluprinted for $1,695 delivered. With my 461 big valve heads, it looks pretty darn close to stock but has torq out the wazoo! For just foolin' around when in the mood, I could not be more pleased with the performance. Now if I can just find the time to enjoy it.

oldandtired

If more is better, then too much is just right......

GDaina

I can solve your dilema real quick, whether to buy or rebuild...

for the price of a new motor, whether it's a zz4 or a 383, you end up with two motors, yours and the new purchase...you can keep yours or sell to reduce the purchase price. The way I look at it, two for the price of 1 is better than just one..plus the time factor, buy it install it, you're done, no waiting for months on a shop...

Gimme1MoreC1

400 HP is a nice target to aim for. Pump gas is another nicety. My previous motor was a 355 dyno'd at 507 HP at the crank With a single plane intake, wild cam, Dart angle plug heads, 750 Holley, etc. It was wild as a deer, but just didn't want to idle, fouled plugs constantly and loved the flavor of race fuel @ $6/GL. It was a handful for sure and pulled like a mule to 7000 RPM. BUT, all of this at a price of constant tuning, blowing out power valves in the Holley, and not enough vacuum to make the power brakes function properly (I could get one soft application, then it was all leg). Now I have re-installed the original motor, built to factory L79 specs, and yes, I admit I miss the extra 150 HP, but pump gas, no adjustments, belts stay on, and now I can get the fact A/C running again. I like the ZZ383 for good balance, and would go that direction, if I was starting from scratch. Good Luck, you'll make the right decision.

rfisherman

I helped a friend pull my original 327/350hp out of my 66 roadster and tag and bag it. We then droped in a zz383/425. Two years now and I still can't keep the tires hooked up. It was the right choice then and I will not look back.

midyearvette

you are looking for torque here in a street engine, horsepower is important but torque is KING......case closed