i have a 89 camaro with a 95 impalla lt1. mods include cai,headers and flows,pcmforless performance tune.
any way i was wandering if puting aluminum heads on it would be worth any decent gains with a light home porting job. or should i just leave it sence it is my daily driver

 

The stock iron heads probably flow a bit better than stock aluminum LT1, so their biggest disadvantage is their "road hugging weight".

Egypt in OK?

 

yea it should be bfo

 

We always used "EBF" with the "E" being "East".

But then again, I'm from NY. "Back East" to you guys.

If you aren't going to professionally port some aluminum LT1 heads, such as Lloyd Elliott's work, stay with the iron ones for your daily driver. I have 100K miles on my '96 Impy, and when I redo the mill, it will be a 383 with ported alum heads.

 

Iron LT-1 heads = "Vortec" heads, right?

Aluminum LT-1 heads = LT-1 heads that were only used in F-body and Vette, right?

If so, a further complication would be the different intake bolt pattern unless I miss my guess. Aluminum LT-1/4 heads have a bolt pattern shared with no other SBC head, that I'm aware of. If the iron heads on a Caprice LT-1 have a "Vortec" intake bolt pattern they won't interchange anyway.

???? Am I wrong ????

(honestly, I'd like to know)

 

Yes! LT1 head, is an LT1 head, whether iron or aluminum.

 

Yes, you are wrong. The 94-96 Caprice, Roadmaster, Fleetwood, and impala SS each had iron headed reverse flow Gen 2 motors. The LT1 intakes and blocks are the same.

 

Leave the Iron heads,they flow a little better then the aluminum Lt1's as they were in development longer and the engineers were able to squeeze a few more cfm out of them.

 

...and they help keep the front wheels on the ground on a hard launch.

I believe the Vortec ports are pretty much a copy of the iron LT1 ports which came first.

 

Actually the aluminum heads came first as they were installed in the 93 camaro/firebird,the Iron head Lt1 wasnt available in the roadmaster ect. untill 1 or 2 years later. The vortech heads are a copy of the aluminum Lt1 head and flow nearly as well,Iknow as I ran a set of vortech's a few years back and did months of research.Flow them and find out! I was reading a flow comparo about 5yrs ago and they tested the newer steel head to the older aluminum and the iron came out on top,not by much though!

 

Not always

heh, he's talking about the Vortec (which came out in 96) copying the iron LT1 head (which came out in 94). The alum LT1's port was updated in 96 to match the iron LT1's port. I'm sure OldSStroker has flowed his share of LT1 heads. The LT4 head came next in 96 followed by the Fastburn heads sometime later. And then the Gen3 stuff came out...

 

Flow em? I can hardly lift them.

My 100,000 mile 96 Impy barely gets air under the fronts on a hard launch any more. Time to change out the plugs. I'm afraid if I swapped to some aluminum LE2 or 3s I'd have a problem. I guess it would depend on the cam choice.

So why did EARLY truck Gen III engine have iron heads? And why don't they now? Serious question, BTW.

 

I know nothing of gen 3 stuff although it would seem the aluminum version of the gen 3 vortech(Ls1)makes more power than the steel counterparts as guys are swapping to the aluminum.By the way your impalla must run dang strong to lift the wheels olsstroker!

 

good question...


Did you ever get your imp to the track?

 

It's a basically stock Imp. The only time it gets air under the front is when it's on a hoist! JK with the previous posts.

As I understand the story, Gen III engine design was done mostly by "car" gals/guys in Powertrain, and not by "truck" folks. Although first and most visible application was the '97 Vette, it never would have been born without the use of millions of them in trucks. That's basic economics: investing a half billion or (much) more would have made the LS1 for Vettes, F-cars, and the odd GTO and CTSV VERY expensive.

Anyhow, initially the truck folks were concerned about long term durability of aluminum heads in the 6.0 truck engines (LQ4), and pushed for the old reliable cast iron. I don't think GM had ever used aluminum heads in truck SBC previously. Powertrain folks had to convince the truck folks that not only were the aluminum Gen III heads AS durable as iron ones, but actually MORE durable. That took a while, so some early (1999-2000) 6.0L truck heads were iron. They had the same 210 cc/75cc ports and 2.00/1.55 valves as the 2001+ LS1 and LS6 heads, but 71 cc chambers for lower (9.5 on a 6L)compression. They might make a good FI head. They are pretty easy to identify if you run into them.

My $.02