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Discussion Starter · #1 ·
Picking heads for my daily driver...... 1994 Roadmaster Wagon...... Stock cam (for now) possible GM 227 cam in the future. I am looking to freshen up the upper half of the engine. Please keep banter to a minimum. If you do not know what you are talking about or just have a comment please keep it to yourself.

What I have to install:
GM Performance 1.6 rr
Stock cast or stock aluminum heads (will have stock aluminum heads cleaned up).
Crane 10309-1 spring kit for cast heads (If I use aluminum heads I will go to LS1 beehive springs).

I can buy worked over heads as cheap or cheaper than I can have the cores I purchased done. But I do not want to lose to much velocity (effecinency and torque) with "over ported" heads. Gas mileage and torque are key. I pull a 2000 lb camper and LOVE the way the stock motor pulls it. Converter will stay stock for gas mileage.

Should I leave the heads stock?

Do a light port job?

Or just buy these heads/intake and be done?

Lift In. Ex.

100 69 77.2
200 131 146.7
300 181 202.7
400 220 246.4
500 245 274.4
600 255.7 286.4
700 260 291.2

What head gaskets should I use?
 

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......I can buy worked over heads as cheap or cheaper than I can have the cores I purchased done.....
Those exhaust flow numbers are a bit high (IMO)......I'd be real concerned about that in a NA application. I know they're cheap......but they may not be a particularly good deal if they're junk.

With your stated goals.....if I were in your shoes, I'd get those cores ported......with a stated goal of of keeping compression in the 10.5:1 range (maybe 54-56cc combustion chambers) and a mild performance cam like the 227 (that you seem to like).

BTW......a mild cam upgrade with the stock heads is a strong/viable option too.....but not the route I'd take.

But hell......that's just me :cool: .

KW
 

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Either Head is Good.
Port and Polish while they are off.

The 227 is the perfect Street Strip Cam.
Porting will add bhp and higher shift points from better flow.

FWIW ...
Freshen the Bottom Ed with fresh Bearings and Rings.
The new Rings will add 20 more hp.

D
 

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Discussion Starter · #4 ·
Those exhaust flow numbers are a bit high (IMO)......I'd be real concerned about that in a NA application. I know they're cheap......but they may not be a particularly good deal if they're junk.

With your stated goals.....if I were in your shoes, I'd get those cores ported......with a stated goal of of keeping compression in the 10.5:1 range (maybe 54-56cc combustion chambers) and a mild performance cam like the 227 (that you seem to like).

BTW......a mild cam upgrade with the stock heads is a strong/viable option too.....but not the route I'd take.

But hell......that's just me :cool: .

KW
I guess that is the answer I expected...... I agree with those exhaust numbers they are very big.


Either Head is Good.
Port and Polish while they are off.

The 227 is the perfect Street Strip Cam.
Porting will add bhp and higher shift points from better flow.

FWIW ...
Freshen the Bottom Ed with fresh Bearings and Rings.
The new Rings will add 20 more hp.

D
Would love to do exactly as you say. I have an extra motor I could have freshened up and do a complete drop in, but it is a lot more work.
 

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I'd have no concern with high exhaust flow numbers. I just don't believe them. They intake flow looks like stock heads, with possibly inflated numbers at the high lift........which makes me doubt the low lift numbers too. I'd hedge my bet on stock heads rather than these.
 

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Would love to do exactly as you say. I have an extra motor I could have freshened up and do a complete drop in, but it is a lot more work.[/quote]
=====================================
If you have an extra engine.. DO IT !
You are stressing an bottom end with 100K plus miles..
Just clean and add parts..less than $700.

D
 

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i think u should upgrade the head for a l92 and while ur at it put a l76 manifold on top.. now if ur money aint hurting there then i would change the block for a lq4 bottom and u should be about... yeah i think u should be good by then.
 

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I have some nice LE2 heads for sale! sell your stock alums for some cash and have some brand new LE2 heads for about $1000. lmk!
 

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Discussion Starter · #9 ·
Just bought a set of New GM performance LT1 heads....... Got a great deal. Trying to find flow number (if they are different that the stock heads) and info on the double springs that are on the heads. I know they do not flow as well as the cast heads, but not sure about the GM performance stuff.
 

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Just bought a set of New GM performance LT1 heads....... Got a great deal. Trying to find flow number (if they are different that the stock heads) and info on the double springs that are on the heads. I know they do not flow as well as the cast heads, but not sure about the GM performance stuff.
i didnt know gm made a performance lt1 head. im curious to see the numbers on this too.
 
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