Best iron heads? Advice please.
Thread Starter
Drifting
Joined: Sep 1999
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From: Manassas, VA, USA
Best iron heads? Advice please.
Well, bad news on the Aluminum head plan. We got the new pistons in and checked the deck height, and even with 64cc heads I can only get about 9.5:1 compression (yes, I know I could go to domed pistons, but I'm not going to). I don't want to deck the block because I don't want to ruin the value of my numbers matching engine. Since we won't really get the advantage of the Al heads, I don't want to spend over $1,000 on them. I'm now back to looking at irons.
Originally I thought Vortec heads, but I've heard that they have clearance problems with over 0.400" lift. And my cam had 0.500 inch lift. What have been your experiences with aftermarket iron heads?
TIA. :cheers:
Originally I thought Vortec heads, but I've heard that they have clearance problems with over 0.400" lift. And my cam had 0.500 inch lift. What have been your experiences with aftermarket iron heads?
TIA. :cheers:
Pro
Joined: May 2001
Posts: 524
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From: watchung N.J.
Re: Best iron heads? Advice please. (lyonsh)
I would only advise the sportsmanIIs if you buy them bare and install your own components, I hade 50% of the dampers break in mine until I installed
springs and dampers from comp cams. Otherwise they work very well, I dont know if they come in less than 64cc, have you thought about using a metal
shim head gasket? you can raise comp. over a point by using thinner gaskets.
springs and dampers from comp cams. Otherwise they work very well, I dont know if they come in less than 64cc, have you thought about using a metal
shim head gasket? you can raise comp. over a point by using thinner gaskets.
Pro
Joined: Jan 2002
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From: FL
Re: Best iron heads? Advice please. (lyonsh)
Bravo for considering iron. I am fond of iron and feel just the opposite about aluminum. Plain and simple, I don't think the stuff is tough enough.
It's been a long while since I put mine together. Back then they were simply called Dart-II heads. I got the large port (220 cc intake), large chamber (72cc) models. With my big flat-top (slotted) slugs and zero deck height I get 10.25:1. I ported and polished them and built them up with top of the line hardware: Severe duty undercut valves (Manley), 3 piece 175 lb springs, good steel keepers/locks, double seals (Teflon and rubber umbrellas), screw-in big block studs, and guideplates.
By the way, nothin' says you can't run your coolant cooler with iron heads to get some of the same detonation resistance aluminum is so well known for. I do. :yesnod:
My Dart-IIs have been performing admirably. I have never regretted the choice.
-Noel
It's been a long while since I put mine together. Back then they were simply called Dart-II heads. I got the large port (220 cc intake), large chamber (72cc) models. With my big flat-top (slotted) slugs and zero deck height I get 10.25:1. I ported and polished them and built them up with top of the line hardware: Severe duty undercut valves (Manley), 3 piece 175 lb springs, good steel keepers/locks, double seals (Teflon and rubber umbrellas), screw-in big block studs, and guideplates.
By the way, nothin' says you can't run your coolant cooler with iron heads to get some of the same detonation resistance aluminum is so well known for. I do. :yesnod:
My Dart-IIs have been performing admirably. I have never regretted the choice.
-Noel
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Re: Best iron heads? Advice please. (lyonsh)
Vortecs can handle up to .460-.470 without doing anything to them. But it only costs about $80-$100 to get the valve guides cut down and the spring pockets widened. Then you should really get screwed in rocker studs, I haven't priced that since I installed my own (the studs are easy to get out, and Comp and Crane both sell a cheap tool that helps in installing them.) Then you can run any high lift spring you want.
The real problem with Vortecs is the specialized intake and no EGR. If you take them to get them machined you might as well have the temperature sensor hole bored and tapped for the bigger sensor that the C-3 uses. I didn't and really regret that move, finding a smaller sensor that is compatible with the early C-3 temp gauge.
If you are going to do all that work, you might as well buy a set from one of the Chevy dealers like Pace or Scoggins-Dickey, that have already been modified with all the good upgrades. I've seen them complete in the $600-$650 range.
Dart Iron Eagle heads are a very good choice for inexpensive performance heads for a C-3, but I think that with a little work the Vortecs can be another good choice for C-3 owners.
The real problem with Vortecs is the specialized intake and no EGR. If you take them to get them machined you might as well have the temperature sensor hole bored and tapped for the bigger sensor that the C-3 uses. I didn't and really regret that move, finding a smaller sensor that is compatible with the early C-3 temp gauge.
If you are going to do all that work, you might as well buy a set from one of the Chevy dealers like Pace or Scoggins-Dickey, that have already been modified with all the good upgrades. I've seen them complete in the $600-$650 range.
Dart Iron Eagle heads are a very good choice for inexpensive performance heads for a C-3, but I think that with a little work the Vortecs can be another good choice for C-3 owners.
Instructor
Joined: Oct 2001
Posts: 224
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From: Austin TX
Re: Best iron heads? Advice please. (lyonsh)
When I first got my car back on the road my vac. advance was sticking and I didnt know it. (Problem cured all the heating probs with high revs.) Even after blowing a fan belt and running the thing to 300!! (total accident and could kill pep boys for the faulty altenator that threw the belt) the irons still seals and kept my engine running....I think the al. would have warped and blew the gasket. So with our such high engine temp cars, for a daily driver I wouldnt use anything other!!!
Thread Starter
Drifting
Joined: Sep 1999
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From: Manassas, VA, USA
Re: Best iron heads? Advice please. (Smokehouse69)
Thanks for the input so far. guys. :cheers:
But I'm surprised there aren't more opinions. Are all you "iron-heads" just ashamed to speak out around the aluminoids?
What about World Products heads (not just Sportsman II)? Any more opinions on those?
But I'm surprised there aren't more opinions. Are all you "iron-heads" just ashamed to speak out around the aluminoids?
What about World Products heads (not just Sportsman II)? Any more opinions on those?
Drifting
Joined: Nov 2000
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From: Honolulu Hawaii
Re: Best iron heads? Advice please. (lyonsh)
I think you are making a wise choice based on your compression circumstances. I run Sportsman IIs and find it a very versatile head. Although my motor is no where near the horsepower potential of these heads, they run real good on the street. Magazine articles (if you are inclined to beleive what they say), report that the Sportsmans behave like the SR Torquers up until 3000 rpm. From there they start to really shine.
Based on 1/4 mile mph calculations, the SIIs gave me 55 bolt-on horsepower vs. stock smog heads.
Regardless of what heads you end up getting, MAKE SURE YOU TAKE IT EASY ON THEM THE FIRST TIME YOU START HER UP. I've READ that the springs need to go through an easy hot-cold cycle first to avoid potential breakage. I don't know the reason behind this recommendation, but since it is easy to do, I did it. So far no spring breakage problems. Good luck with your build.
Based on 1/4 mile mph calculations, the SIIs gave me 55 bolt-on horsepower vs. stock smog heads.
Regardless of what heads you end up getting, MAKE SURE YOU TAKE IT EASY ON THEM THE FIRST TIME YOU START HER UP. I've READ that the springs need to go through an easy hot-cold cycle first to avoid potential breakage. I don't know the reason behind this recommendation, but since it is easy to do, I did it. So far no spring breakage problems. Good luck with your build.
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Re: Best iron heads? Advice please. (lyonsh)
Remember that you can get a set of L98 alu. heads with 58cc chambers and have higher compression with flat tops. That is what I have. I got them for $550 with new valves, springs, 3-angle valve job, guide plates, straight milled .010" for 57cc chambers, and screw-in studs. The only problems are that you are limited in valve size (1.94/1.50 stock) and you have to use center-bolt valve covers. You can take the valves out to 2.00/1.55 or 1.94/1.6, but mine are staying where they are. If you are not going above 5500-6000 it shouldn't be a big deal anyway. The S/R's or most others will out-flow them out of the box but I am getting mine bowl ported and for a stroker that should be fine. Just a thought.
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Re: Best iron heads? Advice please. (compuvette)
Another vote for Sportman II but you might want to buy the bare heads and add your own hardware.
There are other choices and one is GM Performance heads, I never hear anyone talking about them but wouild like to know what people think.
Fast Burn aluminum heads for about $700US check it out:
Also some iron heads there too, I wonder if anyone has tried these.
http://www.johnbear.com/cylinder_heads.htm
[Modified by MotorHead, 3:24 PM 2/18/2002]
There are other choices and one is GM Performance heads, I never hear anyone talking about them but wouild like to know what people think.
Fast Burn aluminum heads for about $700US check it out:
Also some iron heads there too, I wonder if anyone has tried these.
http://www.johnbear.com/cylinder_heads.htm
[Modified by MotorHead, 3:24 PM 2/18/2002]
