5.3L Build! (HELP)

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Aug 13, 2020 | 11:49 AM

SingleCabSierra

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5.3L Build! (HELP)

Hey, I need some help picking the right cam for my build. So basically what I have is a stock 5.3l engine that I’m putting 317 heads that are milled .030.. what cam will be the best for max Hp for my build. If you have any other questions just let me know and I’ll try my best to answer ASAP!

Aug 13, 2020 | 01:46 PM

G Atsma

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From: Central Cal.

Which car, what sort of use, street, race, or both?

Aug 13, 2020 | 01:51 PM

SingleCabSierra

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Quote:

Originally Posted by G Atsma

Which car, what sort of use, street, race, or both?

it’s a 2004 GMC Sierra single cab and also street/race more the race side lol

Aug 13, 2020 | 04:02 PM

1FastBrick

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From: JunkYard

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Originally Posted by SingleCabSierra

Are you going with forced induction later? What's the purpose of going to a 317 head???

Aug 13, 2020 | 04:19 PM

SingleCabSierra

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Quote:

Originally Posted by 1FastBrick

Are you going with forced induction later? What's the purpose of going to a 317 head???

I read that the 317 are the same port design as the 243 and 799 so I got those and had them milled and I’ll probably spray it or turbo it down the line..the 243 were just way to hard to find for a decent price

Aug 13, 2020 | 04:34 PM

1FastBrick

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From: JunkYard

Quote:

Originally Posted by SingleCabSierra

A standard 5.3L with 706/862 heads is around 9.5:1 compression.
A standard 706/862 head is 61CC
A standard 317 Head is about 71CC

Even if you milled them enough to achieve 65CC you would be just below 9:1 compression...

I really wouldnt worry about port shape or overpaying for 243/799 heads. You can achieve the similar flow numbers from a 706/862 head by increasing the intake valve. They have a small 1.89 valve. You can install a 2 inch valve and open the throat up when doing a valve job.

Aug 13, 2020 | 07:52 PM

G Atsma

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From: Central Cal.

You might not want to go bigger than 1.95 on the intakes in a 5.3 to avoid shrouding the valves. WCCH uses that when doing 706/862 heads for 5.3's for that reason.