L98auto

Are the iron heads found on early '86 Vettes the same as '85 heads?

corvettenorway

yes ! 462624 casting nr !

L98auto

Thanks!

ghoastrider1

and neither one flow very well.

corvettenorway

gerardvg

Well the flow limitation is the TPI inlet isn't it ?!?
Way back wheni had the old standard engine, simple add on's like headers cold air intake, airpump delete and adjustable fuel pressure regulators. Tuning and trail and error i managed to get my 85 from the standard 14.4 seconds quarter mile to 13.2. Not bad for TPI and std cast iron heads.

Now with my 383 i could not justify spending thousands on AFR heads, mini ram manifold to make it worthwhile. with a blower i just get more h/p torque everywhere and can spin into the redline easily.

The cast iron heads are not as bad as people make out, my old 350 did more than 170,000 miles no head gasket problems like alloy heads. The rings were not coping with the boost and could not seal, the heads were checked and were good to go.

Joe C

three of the four C4's I've owned have been L98's - two aluminum head, and one iron head. my preference, my 2 cents, and FWIW - I'd take an iron head L98 over the aluminum head version any day of the week. heat wise, my old 85 has been to hell and back - more than once. I doubt, either of my 90's would have faired as well.

flow wise, w/ gerardvg - limited by the TPI inlet -

sorry to get OT -

DanielRicany

I disagree with the iron heads flowing well claim. I had a flat tappet zz409 cam, headers, miniram, 3.75s, 58mm throttle body, and all the free mods and some miscellaneous mods, and I couldn't even keep up with a stock C5. Now I have AFR heads, and I can guarantee it'll blow them away!

Joe C

who made that claim?

Tom400CFI

And futher more...you can't gaurantee squat. You haven't even got the car running yet, based on other posts I've seen..

Something was very wrong w/your original combo if you couldn't keep up w/a stock C5, with the parts you listed.

ghoastrider1

my statement wasn't very clear. The iron heads AND the alum heads don't flow any better than the old fuelie heads., The vortec and aftermarket heads flow better , hands down. Sure, the old heads could help your car go fast, and many did, but they need expensive work to flow as well as newer heads.

DanielRicany

Well apparently you haven't been seeing anything. If you read my previous threads you would have seen that I have been driving it. And yeah, what was wrong with the previous combo was the iron heads!

cohocarl

And the "624's" in the day were put in V8's (76cc b.t.w.) on several different GM vehicles and were not Corvette specific like the aluminum "113" heads.

But if you wanted to sell your 624 heads on Ebay, be sure to say "Corvette" heads so someone will pay more money for them....

Tom400CFI

Negative. Plenty of people have been able to get "C5" levels of performance out of heads like that. I was, using worse 882 heads, and CFI!

Since your driving it, and you can make a "guarantee" on your C5 beating performance, what are you 1/4 mile times?

DanielRicany

Haven't run it yet.

Tom400CFI

There you go then...you can't guarantee squat. SOTP meter don't mean squat.

powerpigz-51

Here are the flow rates i could find in the 624's and 113's.

624 heads-

198/134@.400
216/139@.500

113's-

189/157@.400
190//171@.500

The iron heads have the advantage on intake flow, the 113's on exhaust. The D shape raised port does the job. Seems like a wash, except the small chamber on the 113's seem to give a compression advantage, and of course, a weight advantage. But even a crappy pair of aftermarket heads are superior performance wise. Flow numbers for the 624's was hard to come by, so I cannot confirm them as they came from one source. These were the 1.94's.

milsurpman

One thing about the 624's is I had a hell of a time giving a set away(free). In the future if I ever somehow end up with a another set I will use them as Lawn art out by my shop.

corvettenorway

http://www.joby.se/corvette/div/vetteinfo.htm

HlhnEast

They may not flow like aftermarket but if I would have had aluminum heads when I blew my head gasket, they would not have survived. Exhaust into coolant raised temps higher than I thought the gauge went. Had to nurse it home a couple of miles at a time with 30 minute cool down cycles. Hit 260* and pull over, Repeat, repeat, repeat. Took the iron heads in and they did no more than do a light mill and freshen the seats and valves with new seals. I woulda been shopping for new heads had they been aluminum. Until I break down and throw some thousands at the engine, I will stick with iron and be thankful.