92 GMC Typhoon T76, 4L80E, AWD, Forged 370
#22
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Not trying to sound like a jerk here but you have too many mismatched parts. Before buying anymore parts do some research. Those pistons with will yield at best 8.5:1 compression with those heads, and that's if they are milled enough. The problem with milling stock castings is you will lose deck thickness and clamping force. Neither is good for forced induction motors if you plan to run much boost. The cam you have is a hydraulic roller cam not a solid roller like your lifters. The valve springs are great for that cam but will not work for solid roller, they will need to be a good bit stronger to run high RPM's and the higher lift associated with solid roller cams.
My advice would be to look for a set of 799 heads to bring the compression up. Sell the solid roller setup since you will not benefit by having them at all, and get stock rockers and lifters. That cam and springs will work and has been proven. Not the most ideal but will work. The turbo will be fine unless you are planning to go for big numbers, but will work fine for up to 650 to 700 rwhp which is all that cam and springs is going to let you make.....Just trying to help you from making a huge mistake buying the wrong parts, not putting you down.
My advice would be to look for a set of 799 heads to bring the compression up. Sell the solid roller setup since you will not benefit by having them at all, and get stock rockers and lifters. That cam and springs will work and has been proven. Not the most ideal but will work. The turbo will be fine unless you are planning to go for big numbers, but will work fine for up to 650 to 700 rwhp which is all that cam and springs is going to let you make.....Just trying to help you from making a huge mistake buying the wrong parts, not putting you down.
#23
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Not trying to sound like a jerk here but you have too many mismatched parts. Before buying anymore parts do some research. Those pistons with will yield at best 8.5:1 compression with those heads, and that's if they are milled enough. The problem with milling stock castings is you will lose deck thickness and clamping force. Neither is good for forced induction motors if you plan to run much boost. The cam you have is a hydraulic roller cam not a solid roller like your lifters. The valve springs are great for that cam but will not work for solid roller, they will need to be a good bit stronger to run high RPM's and the higher lift associated with solid roller cams.
My advice would be to look for a set of 799 heads to bring the compression up. Sell the solid roller setup since you will not benefit by having them at all, and get stock rockers and lifters. That cam and springs will work and has been proven. Not the most ideal but will work. The turbo will be fine unless you are planning to go for big numbers, but will work fine for up to 650 to 700 rwhp which is all that cam and springs is going to let you make.....Just trying to help you from making a huge mistake buying the wrong parts, not putting you down.
My advice would be to look for a set of 799 heads to bring the compression up. Sell the solid roller setup since you will not benefit by having them at all, and get stock rockers and lifters. That cam and springs will work and has been proven. Not the most ideal but will work. The turbo will be fine unless you are planning to go for big numbers, but will work fine for up to 650 to 700 rwhp which is all that cam and springs is going to let you make.....Just trying to help you from making a huge mistake buying the wrong parts, not putting you down.
Now for the lifters and valve-train, i have been debating on selling them and just going to with LS7 lifters, zo6 pushrods, and stock rockers. I have everthing else but the lifters.
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here is the info on combustion chamber volume http://www.performancetrucks.net/for...-heads-442909/
here is the compression calculator http://www.csgnetwork.com/compcalc.html
with your current setup the cr will be low 8s.
with out changing your pistons, the 243, 799 head is your best choice, even a 241 over your current setup. you have to change your lifter to a hyd, roller.
what converter are you running? the 80e has a higher first gear, 2.48 first gear vs 3.060 for your 4l60. will result in a big disappointment.
here is the compression calculator http://www.csgnetwork.com/compcalc.html
with your current setup the cr will be low 8s.
with out changing your pistons, the 243, 799 head is your best choice, even a 241 over your current setup. you have to change your lifter to a hyd, roller.
what converter are you running? the 80e has a higher first gear, 2.48 first gear vs 3.060 for your 4l60. will result in a big disappointment.
#27
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lol I was posting on moblie phone, i just noticed your user name for the syty forums. I know it want spool well i was thinking like a 2500-3200 stall just started looking for waiting to find a good deal. Did you use the rpm 4l80e shift cable?
#32
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Your typhoon was sooooo nice!! and the trans am too lol. Ya i know the feeling, i has to send back parts that were wrong and wait for parts that they never shipped the first time. Decide not to use their pan for the Ty, so i cut up and factory pan so i did have the run oil lines in the engine bay. I have over 5 years in to this project, making all fit is the hardest part.
#34
I doint know much about them turbos, but im pretty sure they are a copy of the tc76. The tiny exhaust wheel will hold you back. On a 370 with a precision pt76 is a fun quick spooling combo...and thats a lil close to maxing out that turbo
#35
Your typhoon was sooooo nice!! and the trans am too lol. Ya i know the feeling, i has to send back parts that were wrong and wait for parts that they never shipped the first time. Decide not to use their pan for the Ty, so i cut up and factory pan so i did have the run oil lines in the engine bay. I have over 5 years in to this project, making all fit is the hardest part.