I mean I take it for their price they aren't incredible flowing heads, but are they half decent? I'm trying to get a budget 350 together and I want a set of cheap heads that will still give me decent horsepower numbers until I can afford a good set of heads.
http://cgi.ebay.com/ebaymotors/ws/eB...tem=1873085788
I'm looking to using the Xtreme Energy 274, 1.6 rockers, Weiand Stealth Intake, and I'm not sure on the carb yet, but that is a basic run-down of what I want, and am looking for a 375-400 hp combo with a good set of heads on it.

 

These are one of the better smog open chamber heads.
They will not make 375/400 hp as they are.
They would need to be generously ported. Bigger valves would be nice too.
The EXTRA cost z28 springs would be the minium required
Remember that in the price + shipping.
They will make about 330 hp as is, on the motor you discribe.
They are 76cc's stock. Unless they are milled down, they will not make 10:1 cr with a flat top 350.

I would consider buying a better "Budget performance" 64cc head like Vortec's. Dart Iron eagles or Pro topline 180cc iron heads. They will make the power your looking for.
The little extra money on better heads will return the performance you're after without having to port them yourself.
Goof proof.

In the mean time you can/ could buy a set of stock 882's or 305 heads for $100 till you save for the better heads.

 

What heads do you own right now?
casting #'s?

 

Whatever heads are stock for the L69.

 

Why don't you just port those ones?
They're actually better then 487 heads for your application.

 

With a little work the L69 heads (416 casting) is a far superior head. The only problem with them is that they come with a 58cc chamber which will bump up the compression a bit.

 

that's a problem?

 

Well with a low octane fuel on the street with flat top pistons, yes. Depends what kind of relief he's using on the pistons, or no relief at all.

 

Well if you want to go faster aren't you going to have to
put more in. {$$$'s gas etc.} Can you get something for nothing?

 

It is just an L69 so it ain't packing serious compression anyway. Lucky if he's got 9:1, so a good port and polish job is the cat's meow for him.

 

Vortec Heads are the way to go. You can get them for under $250 for a complete set just about anywhere including GM Performance stores. These will give the most bang for your buck, if not then I would just have your first set ported like F-BIRD'88 says. But you might pay more for that. You might need a vortec intake also but hey there not that much$$$ and its just worth it if your gonna take your heads off anyways.

 

You have mail!!!!!

 

https://www.thirdgen.org/techbb2/sho...869#post847869

 

I have those heads on my firebird, and they are alright. The springs on mine float bad but thats my own dumb fault for not replacing them. But before I wore the springs out and busted the fuel pump, it was quite fast, and still can bake the tires through 1st gear with a 350. But I am buying new heads this winter for the car. Will I chuck these heads, no way, but I want more compression and more flow, and I dont feel it is worth it to rebuild these heads. They may end up on my next project.

As of now though, with an XE 262 cam, my car is much faster than any 305 Ive run into, and is as quick as my buddies highway geared LT1. Food for thought.

 

He's putting them on a 350. Not a 305.

And the L69's had 9.5:1 compression from the factory anyway, which is pretty reasonable.

 

Yeah he's right, it is going on a 350.

 

Bill you already own the best set of "Budget hi perf head" castings
going. $ best bang for the buck$

All you need to do is thouroughly home/port them and upgrade to
a set of budget 1.94x 1.60 valves and some new springs.
You can "pin the studs" if you're "pressed in stud" paranoid.
When you're finished, your chamber cc will be 60/62cc's.
Just right....
(Valve deshrouding)
You can achieve 235/240 cfm in and 180+ ex flow, as I do, with these heads. All you need to do is put the time and effort in.

Search my past posts on the subject, its all there.

 

I'm not going to be able to upgrade the valve sizes on my own, a machine show will have to do that right?

 

You are quite right! My mistake

 

Thats right. Take the heads with you to a shop, to get and estimate on this. Then take them home and port them and pin the studs. Then take them back and drop them off. They will cut in a new valve job for the new valves for ya. Have them install the valves and springs for ya if you don't know how.
To eliminate the exhaust rotator/retainers U just shim the exhaust spring seat up with .105" of spring shims and use a stock chevy retainer. gives you 1.70/1.73" installed height.

Don't over $work$ them. Or let the shop over $work$ them.

Not all heads need the guides repaired. If yours are not worn,
skip this operation. Unless they are exessively worn,
a guide knurling and ream is good enough for 50,000 miles more.
Talk this over with the machine shop. Let them know you're on a budget. You should be able to pull this off for $350/$400US tops.


If you want to use 1.6 rockers , you may have to elongate the pushrod slot in the head. I do it with a rat tail file in a drill.
You'll find this same rat tail file real useful on the intake port walls and roof too.

 

I just got the book How To Build the Smallblock Chevrolet from Summit today. I don't know a lot of the terms or the names of the tools yet, haha. Oh well, looks like it could be an experience, but I do know a couple of people who may be willing to help who do have experience. Now I just need to save the $$$. I'll rework the heads I have now, unless I find a good deal on a good set of heads.

 

Vortec Heads and Intake, Its a Direct replacement and yes for your TBIs and TPIs. A friend of my tried it out and we run SCCA Solo 2(this is a once a month get together where people bring their street camaros, mustangs, civics, mom's groecry getter for fun) with our camaros (Both TBI) and he said he felt a pretty good bit of difference in the car as he would pull out of a low speed corner. So my Guess would be that the set is a Low End Torq deal, which is always fun I wish I would of kept my 305 and made the swap out myself:

 

Hmm, what about L98 heads, how would they compare to the "souped" up heads off the L69?

 

The iron L98 heads 081 for 305 and 083 for 350's
has the same potential when ported as the 305 416 castings.

check out this link
http://www.fl-thirdgen.org/head_porting.htm


here is a flow test of some iron L98 heads done by a fellow
thirdgen.org member:

L98 cast heads 083
numbers are:
Lift Intake Exhaust
.1 63.8 41.4
.2 120.6 88.2
.3 178.9 124.1
.4 215.2 154.3
.5 240.1 171.8
.6 241 180

This agrees with what I get with the 416 casting heads
after porting and larger valves.