Does anyone know right offhand what the largest size valves are that can be used in LT1 heads without changing the seats?

 

Increasing the valve size over the stock 2.00" intake does not really increase flow. I would keep it stock if i were you.

Sorry thats not really an answer to your question, but i don't know that one.

 

I thought the LT1s had 1.94/1.5 valves??

 

Nevermind, i'm retarded. You are correct i was thinking about the LT4 for some reason.

 

My reason for asking is because I'm planning to buy a set of LT1 heads to mod for use on my SBC1 block. I already have some 2.02/1.6 valves that I could use with those, and I'm wondering if they'll fit with the stock seats.
Or would it be better to turn down the valves to 2.00/1.55" or maybe 2.00/1.6 to be used with the stock seats?

 

ttt

 

Since you are shopping for LT1 heads, you might consider the iron heads over the aluminum variety. If you do some homework, you might discover that the iron heads flow better than their aluminum counterparts at least through the 1996 model year.



As an added benefit, the iron heads can be machined for big block valves, and easily have space for 2.05 or larger intakes. My iron heads on the "beater" have 2.02/1.60, and have room for a little more. The real beauty is that the induction hardening of the exhaust seats is plenty deep for larger valves. Cutting aluminum heads may require you to replace the seat inserts, which removes any economy from reworking them versus buying new castings that are already better.

FWIW, I know they flow better than the aluminum LT4 heads with 2.00 valves.

 

Thanks Vader
I've heard that the iron LT1s flow better. But this is for a retrofit to a Gen1 block, and from what I've been reading, the iron ones can't be modded for that. Is that true?
The iron ones are dirt cheap on ebay, I'd get some if the retrofit would work.

 

the irons flow better then the early aluminums...from 94 on the aluminums flow better...the LT4's flowed 242 from the factory....mine have 2.02 1.60 and flowed 248