Supercharger, engine rebuild, & compression ratio

90muustanggt

Founding Member

Sep 3, 2001

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Northern VA

Jan 31, 2004

#1

• Jan 31, 2004

• #1

I just finished my engine rebuild. Its a mild rebuild with gt40p heads and a summit forged rebuild kit. The problem is that summit rates its forged rebuild kit at like 12:1 and the GT40P heads are supposed to raise the sompression ratio more.

Can someone explain if the 12:1 ratio is correct for the summit kit and will i be able to supercharge it?

 

90muustanggt

Founding Member

Sep 3, 2001

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Northern VA

Jan 31, 2004

#2

• Jan 31, 2004

• #2

NM i just rered that it is 10.13:1 with the summit kit. Whit the GT40P heads is this too high compression for a SC?

 

nito88stang

Founding Member

May 23, 2002

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Fullerton, California

Jan 31, 2004

#3

• Jan 31, 2004

• #3

I did the same thing, mild build with P heads but went with the hyper 9.08:1 kit instead. 10:1 can be supercharged but you'll definitely be running premium gas with low initial timing. I dont think you'll be able to run much boost though. I myself am content with 6lbs. Hopefully someone with more exp will chime in.

 

Rick 91GT

Mustang Master

Nov 29, 1999

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PA

Jan 31, 2004

#4

• Jan 31, 2004

• #4

What is the cc of the head, deck height of the block and the cc of the valve reliefs, what thickness gasket are you running?

 

90muustanggt

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Sep 3, 2001

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Northern VA

Jan 31, 2004

#5

• Jan 31, 2004

• #5

i have no idea, this was my first rebuild. I am running GT40p heads whatever the cc is of them. a stock (brand new) 5.0l block and the speedpro pistons that came with the kit. I am using a felpro head gasket. would a thicker gasket help any? Sorry for my crappy knowlege of engines

 

Rick 91GT

Mustang Master

Nov 29, 1999

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Jan 31, 2004

#6

• Jan 31, 2004

• #6

DId the pistons come to the top of the block surface/bore, were they under or were they above? If so what is that measurement

 

90muustanggt

Founding Member

Sep 3, 2001

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Northern VA

Jan 31, 2004

#7

• Jan 31, 2004

• #7

they came just about to the top of the deck. they had 4 reliefs i think they are called for the valves. Sorry i didnt take a measurement. all i did was buy the kit, get the crank and rods cleaned up and put it all into a new finished bore block. Not the best way to build is it? I'm also guessing because i didnt take measurements that there is no way to accuratly judge the compression ratio? Oh well it was my first build, live and learn i'm only 19. But any info will help greatly!

 

Rick 91GT

Mustang Master

Nov 29, 1999

9,692

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PA

Feb 1, 2004

#8

• Feb 1, 2004

• #8

Is this the piston PT# you have UEM-KB115030-8? Was the motor bored .030?

What pt# kit did you get?