Hello,

I'm working on restoring/repairing my first, which is an 87 IROC-Z Convertible. I bought it 2 years ago, and it had been previously stolen and pretty much gutted. The engine in it now is a 350 small block with a 4bbl carb, which had to be rebuilt the day after purchase (due to a spun bearing). It's been alot of work just fixing all of the wrongs. I doubt I'll ever take it back to the original TPI status, as the harness is diced quite well, and I haven't had any luck finding one yet.
So here is important question number one. After upgrading the intake and carb (an Edelbrock intake and a Holley 650 cfm dual feed)...the rebuilt motor pressed two rocker studs out of their seats. So, I pulled the heads, pulled all the studs, tapped the heads and installed threaded studs. I cleaned the heads, repainted them, and re-installed them to the block. This is where it sits now. I'm going to upgrade the timing to a gear drive, but want a little more cam. So the question is, with a stock engine, can a cam with a .480 lift and a set of roller-tip rockers (1.6:1) work with these stock heads? The engine is roughly a 1977 350. I can get the stamp numbers, if needed. I have been told by a few that it will work, as long as I also upgrade the trans and exhaust, which I'm doing. I am going to install a 2300-2500 stall (B&M) non-lock converter and a Reverse Manual valvebody into the 700-R4. Are there any sites out there that cover info on specific engine specs...(ie - max cam lift on cyllinder heads, be it stock or high performance)?
I just want to ask some of the more experienced out there before I go through all of the work with negative results. I thank everyone who takes the time to read and reply, and look forward to your input.

Thanks again,

Ace

 

Definitely get the casting numbers of the heads - Both of them (in case they are different). If the engine is a 1977 and the heads are the same vintage, there's little sense in spending any more time or money on them. The '70s heads were typically so poorly cast and machined that there is no way to predict what kind of lift they will tolerate, since valve guide machining depth varies. You could recut the guides, but that would be spending more money and time with heads that are probably best for recycling. Pull your new studs and install them in something better.

Casting numbers?

 

Okay, here are the casting #'s on the heads (they're luckily both the same):

333882

I looked them up, and it shows them with a 350/400 CID with an intake of 1.94, an exhaust of 1.5, and a 76 CC.

Since the motor was rebuilt, I'll have to contact Amcar tomorrow and see if I can get any information on whether or not they changed the valve & CC sizes. Another thing, when the motor was rebuilt, I did pay an extra amount to have a "slightly beefier" cam put in, but I don't know what it's lift and duration is. Hopefully, they can answer that question, as well.
Still...if the heads were in complete stock condition, will it work? Will it work with the .480 lift/ 280 adv duration (230 @ .050") cam and 1.6:1 roller-tip rockers? Or, with the cam it currently has (which has a smooth idle) and the 1.6:1 rockers?
Thanks again for your input and help with this matter!

 

Unless you have a door that won't stay open on its own, don't keep those heads around. They are the epidome of what Vader was describing.

Someone will probably say, "I read this high performance book that said these heads can be made to work..." Sure, if you spend at least as much money on them as readily-available aftermarket performance heads would cost, and said aftermarket heads would perform better out of the box than those heads would after all the money was spent on them.

It's so easy to do better than those heads, it doesn't make any sense to do anything with them.

 

Fair enough. At this point, I'm going to keep the current cam in it and just add the 1.6 rockers, a stall converter and a nice exhaust upgrade with headers. Then, I'll start getting ready to build a 383 stroker for a later swap. Thanks Vader and Five7kid for your input and assistance!

 

LMAO! You're killing me over here!

Ace,

I'd have to agree with 5-7. You can perform a search (either here of across the entire www) for 882 heads. If you're not attached to them, you should get a giggle or two from the results.

As for your initial question, i wouldn't trust the machining on those castings enough to say that they would tolerate 0.480 lifts. You may crash a retainer into a guide. The only way to be certain would be to check every one (since they can vary on the same head) and adjust as necessary.

If you want to retain factory iron heads, the older style intake bolt pattern, and perimeter bolt valve covers, check around for '416 castings.