Considering a head swap, suggestions?

[SappySE107]

Watch ebay for cylinder heads. I never pay more than 50 plus shipping for a set, unless i have to have them asap.

[ForcedFirebird]

I haven't flowed an iron head to compare its flow vs a gen 2 3.1. I have the 2.8/3.1 heads flowed and on the site. I wouldn't use the 3.1 heads when you can use 3400 heads. 3500 heads won't fit a 3100 bore.

The iron heads have a lot bigger CC than the aluminum heads. I can modify a 3400 head to have a large combustion chamber but you would still be running high compression. With proper tuning and a good cam, thats not a problem.

SFI requires the ECM, not the top end. The SFI manifolds flow better than the MPFI manifolds. Again, not sure on iron head stuff, so im commenting on aluminum head.

How high of compression? I have a CNC machinist in my pocket (good friend plus I'm remodeling his house) I just don't know how much material is there that can be removed without trying it, and the cheapest JY AL's I can find local are $75 each.
When I get the pistons, I'll see if they can be dished slightly also.

[ForcedFirebird]

1. I think the 3.4L Camaro heads flow a little better then the 3.1L aluminum heads, but I can't find any specific data right now... Can anyone confirm this?
The newer 3100 and 3400 aluminum heads flow way better then the old 3.1L and the 3500 heads outflow everything.

The Camaro heads I looked at are iron.

2. The aluminum head cc's are all nearly the same. You're looking at approximately 12:1 compression with Camaro pistons and aluminum heads.

12:1, isn't that conservative? I've heard it was closer to +13:1 (unconfirmed). With this question, I was asking what are the largest chambers for the AL heads, and what did they come out of (year)?

3. SFI is a form of MPFI that gives you better mileage, and is only a function of computer programming. Without an OBD2 computer, your car will be MPFI.

The reason would simply be that the port pattern looked different on the SFI from the MPFI. It looked to me that I would need to use the SFI IM to go with the heads.

You could look at getting an entire top end from a 2000+ 3100, or a 3400, or best of all a 3500. With any of those top ends you'll be doing way better then with your current top end, but you'll have to change your pistons.

I'm getting such a good deal on the pistons, I want to use them in the next engine. If this means I MUST stay with iron, I will. However if I can mod the AL heads to work with these pistons, would be even better. Either way the heads would go on the current engine that has the pistons that mate with the iron heads.
Does anybody know if there is enough material in the chambers of the aluminum's to lower the CR enough to run on pump gas?
Also thicker head gaskets could be used (would help a little).

[SappySE107]

I haven't flowed an iron head to compare its flow vs a gen 2 3.1. I have the 2.8/3.1 heads flowed and on the site. I wouldn't use the 3.1 heads when you can use 3400 heads. 3500 heads won't fit a 3100 bore.

The iron heads have a lot bigger CC than the aluminum heads. I can modify a 3400 head to have a large combustion chamber but you would still be running high compression. With proper tuning and a good cam, thats not a problem.

SFI requires the ECM, not the top end. The SFI manifolds flow better than the MPFI manifolds. Again, not sure on iron head stuff, so im commenting on aluminum head.

[discostu]

1. I think the 3.4L Camaro heads flow a little better then the 3.1L aluminum heads, but I can't find any specific data right now... Can anyone confirm this?
The newer 3100 and 3400 aluminum heads flow way better then the old 3.1L and the 3500 heads outflow everything.

2. The aluminum head cc's are all nearly the same. You're looking at approximately 12:1 compression with Camaro pistons and aluminum heads.

3. SFI is a form of MPFI that gives you better mileage, and is only a function of computer programming. Without an OBD2 computer, your car will be MPFI.

You could look at getting an entire top end from a 2000+ 3100, or a 3400, or best of all a 3500. With any of those top ends you'll be doing way better then with your current top end, but you'll have to change your pistons.

[ForcedFirebird]

I went to the JY to find a manifold and came across a lot of 3.1's. Quite a few were FWD with aluminum and saw one (93?) Camaro.
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Just a couple of questions...
1. Would the 3.4 Camaro heads flow better than the 3.1(LHO)?
2. If I do go with the FWD aluminum heads, what years had the largest combustion chambers (in hopes of not changing my pistons yet)?
3. Is the SFI better/worse than MPFI (could take the whole top end)?

I really want to use the Keith Black .30 over forged pistons I am looking at (getting them for $100) in my next engine and would like to work a set of heads that can be transferred over to the .30 over block.
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Any suggestions would be appreciated!