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Cross Fire engine build.. Opinions on whats to come.

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Cross Fire engine build.. Opinions on whats to come.

Old 11-20-2018, 06:01 PM
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Car: 1989 Trans Am GTA
Engine: 5.7L 350 TPI (Deleted Cats)
Transmission: 700r4
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Cross Fire engine build.. Opinions on whats to come.

Profiler 195cc heads
10.25:1 static compression
Forged flat tops and rods
Comp xm276hr retrofit roller
Dynamic compression around 8:1 depending on calculator used.
93 octane
Quench will be set around .045
Ebl flash
Long tubes into 2.5 true duals with an x pipe at another time. Cant empty the bank account all at once. Probably in the spring.

Whats everybodys opinion?
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Old 11-20-2018, 10:49 PM
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Re: Cross Fire engine build.. Opinions on whats to come.

Originally Posted by brianlibby791 View Post
Forged flat tops and rods

Quench will be set around .045
"Flat Tops" means NOTHING until you start specifying compression distance. It's REALLY easy to get pistons that sit too low in the cylinder, and then require excess milling of the block decks to get the quench distance right.

Quench at .045 is at the very top of the acceptable range. "I" would look at .035 to .040 depending on piston rock. Engine I'm building now is zero-decked or very close, and a .039 gasket pair. I probably should have left the piston .005--.010 in the hole (less material cut from the deck) and used .029 gaskets.
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Old 11-24-2018, 04:22 PM
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Transmission: 700r4
Axle/Gears: Original 3.27
Re: Cross Fire engine build.. Opinions on whats to come.

Originally Posted by Schurkey View Post
"Flat Tops" means NOTHING until you start specifying compression distance. It's REALLY easy to get pistons that sit too low in the cylinder, and then require excess milling of the block decks to get the quench distance right.

Quench at .045 is at the very top of the acceptable range. "I" would look at .035 to .040 depending on piston rock. Engine I'm building now is zero-decked or very close, and a .039 gasket pair. I probably should have left the piston .005--.010 in the hole (less material cut from the deck) and used .029 gaskets.
Right now they're at roughly the stock depth in the block, (.025) Obviously when the heads come off I'll actually measure the volume exactly and adjust accordingly but using everyone else's findings that's about the height it should be at.... It's a healthy rotating assembly, no sense messing with it at this point. Good compression, no ring blow by. Honestly I thought quench was a .04-.05 target but that's why I asked. I'm by no means an expert on this.
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Old 11-24-2018, 04:55 PM
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Re: Cross Fire engine build.. Opinions on whats to come.

Originally Posted by brianlibby791 View Post
Right now they're at roughly the stock depth in the block, (.025) Obviously when the heads come off I'll actually measure the volume exactly and adjust accordingly but using everyone else's findings that's about the height it should be at.... It's a healthy rotating assembly, no sense messing with it at this point. Good compression, no ring blow by. Honestly I thought quench was a .04-.05 target but that's why I asked. I'm by no means an expert on this.
.025 in the hole, plus a typical .040 gasket = no quench.

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Old 01-23-2019, 05:51 PM
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Car: 1982 Z-28
Engine: 5.7L Crossfire
Transmission: TH-350
Axle/Gears: GM Posi, 3.73
Re: Cross Fire engine build.. Opinions on whats to come.

The stock TBs and Crossfire intake will be restrictions. I would go with an aftermarket Renegade intake. You need to have the stock TBs bored out, but I don't know anyone that does it anymore. After that, its all about fuel delivery and getting enough fuel into the engine. At a minimum, you need to upgrade to Vette injectors and will likely need to bump fuel pressure up as well.

I'm close to maxing out the fuel system with nothing near as radical as you have. See build specs below.
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Old 01-23-2019, 05:54 PM
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Re: Cross Fire engine build.. Opinions on whats to come.

Forgot to mention, fuel pressure currently set at 18 PSI. I've heard you can go as high as the mid 20s, but I don't need that much with what I currently have.
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