Hi all i finally found the motor i want to use in my 1984 Z28 Camaro. I was woundering if you could tell me if this is a good combo? The motor is a freshly rebuilt 400ci small block done .030 over stock bottem, stock rods, pistons are a ??? but i assume it's got stock c/r. The motor is out of a late 70's truck with q-jet and early HEI, and the best part is it's $450 for the whole thing from carb to pan. Now for the combo.

400ci .030over
Brodix Track 1's 67cc (10:1 cr?)
Harland Sharp 1.5 Roller Tip Rockers
CompCams XE284H kit (cam, timing chain, lifters, springs and retainers)
Weiand Stealth Intake 300-36
750cfm BG Carb
MSD Super HEI Kit 6al

What would this run in a stock Z28? DD2000 gives me 435hp@5500 and 451tq@4500. Also do you think the motor will take a 100shot with a stock bottom end?

 

the passengerside pipes for cyls 2 and 8 will touch the front crossmember in about 2 places. Be preparied to get a die grinder out.

 

Thats almost exactly my set up. Except I am running Iron eagles. Your HP numbers are about 25 high. But close. With the stock rods it wont like to rev, 5500, is where it will wind out at. At idle it has a nice lope, but cruising its nice and smooth, Also every now and then you won't have real great brakes. As for nos a 100 shot it should be fine, I have to change rear before I try NOS.
Later
John
The holley intake will be going back in the car this winter

 

Sounds like a very potent mouse

I would go easier on the cam, though. A Comp XE268 is the biggest I'd run. You will have excellent driveability and terrific performance across the rpm range. The 400 isn't a high winding engine and that cam won't pay for its keep until you are running out of rpms. You spend a lot more of your time in the under 3500 rpm range. Don't let the desire for lopey idle fake you out. All that means is a soggy low rpm engine.

 

http://www.brodix.com/onlinecatalog/...page11-12.html

Have you looked at the intake port dimensions on those heads? Do you know if that little bitty emissions-legal street intake will even completely cover the ports, much less port-match up to them?

Brodix recommends 11½:1 CR minimum for them.

Those are essentially pure race heads, not a good match for a street motor at all. Above all, they are set up for MASSIVE FLOW, which means high RPM usage. Not a good match for a stock short-rod cast crank cast dished piston grocery-cart-built short block. All in all, not a good match: way massive huge overkill on the heads, or not enough short block, or both. You can easily make 435 HP with a 350 short block and a set of Vortec heads; there's no point in spending that much money, but only getting that little out of a set of heads that's good for around 550-575 HP at 6500-7000 when installed and configured properly on a 400 CID engine. This would be a classic case of too much money for not enough results.

 

Very few genuine stock 400s exist today with the original pistons, rings, etc. They've almost all had at least one rebuild. Either that or they're locked up so tight you need a sledge hammer to get the old pistons out of their bores!

Lets say you've found one that really IS original. DEFINITELY look at the tops of the pistons before you buy your heads- stock 400 pistons are pretty heavily dished all across the face and have 4 "eyebrows" for valve reliefs as well. If they're flat tops or domed- the motor's definitely been apart at least once. Also, with all the cubes it's easy to send compression to the moon using common 64-67cc heads even with flat top pistons. You'll be at 11:1 before you can blink. Be ALWAYS mindful of your true compression ratio with a big cube small block.

Even if it IS original, are you sure you want to bolt a bunch of expensive parts on a 25 year old short block? Think about this long and hard. It would be a real shame to disintegrate a piston or snap a rod bolt and destroy those nice new heads. The original 400 bottom end will NOT tolerate high RPMs for very long. The stock flimsy rod bolts are usually the first thing to "let go". I ALWAYS install ARP wave loc rod bolts on a 400 bottom end, even if it's a fairly mild one.

The heads you are considering I have never used. I would tend to agree with RB on this one. I've built a LOT of street engines and those heads never made it on the short list. Don't forget about the required STEAM HOLES that must be drilled into ANY head you choose for a 400.

 

As above you should check and calculate your true compression ratio with 67cc heads.

A flat top 400 will want a 72 to 76 cc head depending on your
actual piston deck height clearance.
The track 1's will work fine once you rework the chamber
to get the compression right if nessessary. There is lots of meat there to play with. Target for no more than 10.2:1 just under 10:1 is best. Big bore motors are not as tolerant as say a 350 nor are they need as much cr. Don't get carried away and port them out real big. Keep them small for good volocity.
You don't say what converter or rear gear your going to use.
If you will use a 3000+ converter and high gears the the xe284 will be good. I'd go for a VIc JR intake thou.

If your useing a milder converter then go with a XE274 cam
and the Weiand Stealth. It will be much more snappier with still plenty fo top end with a near stock stall converter. Much nicer to live with overall.

If you have cheap replacement cast pistons then skip the NOS.
They are intolerant of even slight NOS tuning mistakes. (they'll brake)

 

yea i been thinking about the brakes issue i kinda like to stop when i want but the 274 doesn't really hurt the power either from what dd2000 says and i been thinking od dart iron egal heads cause thier $725 for a complete pair