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Discussion Starter · #1 ·
I am building another engine for one of my cars. I spoke with a machinist today about head work, he reccomended putting 2.02 and 1.60 valves in the LT1 heads. Does anyone have a part number on these valves that are the correct length for these heads and where to purchase? I have searched but come up with nothing.
 
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Discussion Starter · #2 ·
Is he blindly recommending that or does he actually have a clue? A LOT of the reputable LT1 head shops like 2.00/1.56. If the guy just wants to blindly throw the biggest possible at it GO ELSEWHERE.
 
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Discussion Starter · #3 ·
Originally posted by Southern Comfort:
....2.02 and 1.60 valves in the LT1 heads. Does anyone have a part number on these valves that are the correct length for these heads and where to purchase?....
JB,

How about the GM parts?

Got those valves (intake and exhaust) in those sizes.....in stainless steel.

PM me if interested.

Dwayne.....now you know that you can't make the statement you made without knowing what JB is trying to do :( ....but I bet his mechanic knows what he's trying to do ;) .

KW
 
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Discussion Starter · #4 ·
Originally posted by KW Baraka:
....Got those valves (intake and exhaust) in those sizes.....in stainless steel.....
OK....wrong answer.

The valves I have are 2.00" and 1.56".

But they are the High Performance steel GM valves
.

My searches show no results for GM 2.02" and 1.60" valves
. Looks like you may have to look to the aftermarket.

KW
 
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Discussion Starter · #5 ·
I know shops are getting 270/190+ with the 2.00/1.56. Bigger isn't always better, better is better and better is determined by testing. Too big a valve will actually be shrouded. If you genuinely believe you need something that big you NEED to work with an expert in those castings.
AI, Lloyd Elliot, Combination Motorsports etc. , guys who know the right valves off the top of their head.
 
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Discussion Starter · #6 ·
OK....found what you say you want.

12363753 MIGHT be the 2.02" valves....High Performance

12363754 DOES equal the 1.60" valves....High Performance

These valves are $22 each!

I'll sell ya the 2.00" and the 1.56" High Performance valves for a bit less ;) .

KW
 
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Discussion Starter · #7 ·
Thanks for the responses.
MGR- The machine that I am referring to is a pretty reputable shop in this area. I called him about getting some porting and polishing done and reccomended going with those valves instead on the LT1 heads. Porting and polishing price that he told me was around 500 bux. Valve work pricing was around 180 plus the cost of the valves.
KW- How much do you want for the 2.00 and 1.56 valves that you have?
 
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Discussion Starter · #8 ·
You will need different valve seats in an LT1 head to take advantage of 2.02/1.60" valves. Might as well go with 2.055/1.60" valves if you.

2.00/1.56" valves will work well with stock seats. 2.02/1.60" will seal fine but you'll end up with a heavier valvetrain without any flow advantages.
 
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Discussion Starter · #9 ·
If you're going with new valves anyway, why not get longer valves so you can use a higher lift cam and still maintain correct geometry?
 
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Discussion Starter · #11 ·
Despite what comment Caprice Mgr said about 2.02/1.60 valve...many of us do use that combo.

Race Prep did my heads with Ferra valves of that size. With a very small cam 214/220, I made 350 HP/350 TQ. Have the same heads on my 383 now.
 
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Discussion Starter · #12 ·
Originally posted by BALLSS:
Despite what comment Caprice Mgr said about 2.02/1.60 valve...many of us do use that combo.

Race Prep did my heads with Ferra valves of that size. With a very small cam 214/220, I made 350 HP/350 TQ. Have the same heads on my 383 now.
You CAN use this combo but if the seats are still stock, all you gained (over the 2.00/1.56" combo) is extra valve weight.

I did run this combo on my old motor for a simple reason, 2.02/1.60" valves are a lot more common and cheaper.
 
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Discussion Starter · #13 ·
Originally posted by BALLSS:
Despite what comment Caprice Mgr said about 2.02/1.60 valve...many of us do use that combo.

Race Prep did my heads with Ferra valves of that size. With a very small cam 214/220, I made 350 HP/350 TQ. Have the same heads on my 383 now.
I didn't say bigger was always bad just that it is not always better the way most people believe.

That power throung a T56 does not suprize me, nor do I think 2.02 valves were necessary to achieve it with that mild cam.
 
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Discussion Starter · #14 ·
Originally posted by stonebreaker:
If you're going with new valves anyway, why not get longer valves so you can use a higher lift cam and still maintain correct geometry?
This is very good advice. .100" longer valves are a very common upgrade when going with new valves.

KW, what is the length of the valves that you have?
 
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Discussion Starter · #15 ·
Originally posted by AdioSS:
.....KW, what is the length of the valves that you have?
GMPP Part# 12363757 = 2.00" Lifter

GMPP Part# 12363758 = 1.56" Lifter

None of the valves featured in the GMPP catalog are advertised as being extra long.....so I surmise that they're stock length.

KW
 
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Discussion Starter · #16 ·
That power throung a T56 does not suprize me, nor do I think 2.02 valves were necessary to achieve it with that mild cam.

96capriceMGR
Member # 635

Dwayne:

the choice of valves was made by Race Prep. I am not the expert, they or any qualified shop is. I took LT 1 aluminum heads in and asked them to check them out and I was getting a 845 cam.

Their response was to go with the 2.02/1.60 and a custom grind 214/220 cam. Instead of bolting on 35 HP I added 90 to the wheels, which is exactly what they said I would get out of the set up.

My goal was to have a car with great street maners, smog legal and...more power. Race Prep delivered.

I now have the same heads on the 383 with a 218/224 cam.

Yes, in going with this valve size the seats need to be worked, which they were.

My point is to listen to the qualified machine shops. I for one, and many opinions on this thread, are not a machine shop.
 
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Discussion Starter · #17 ·
Trust me I am all for the mild cams good heads thing, and yours is an example of how well it can work. Race Prep also knows the LT1 better than most shops. I just think there is plenty of proof out there that valve sized do not need to be the biggest that fit.
 
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