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- - After the math (https://67-72chevytrucks.com/vboard/showthread.php?t=591009)

Zable49

08-01-2013 10:20 PM

After the math

After doing the math and looking up piston #'s. Why would someone build an engine with 7.9 compression and drop it in a truck without running a blower or turbo? Talk about NO power. Guess i should start looking for a set of cheap pistons
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54belair

08-01-2013 10:25 PM

Re: After the math

85 or 86 octane gas?

Lattimer

08-01-2013 11:20 PM

Re: After the math

Possibly didn't know what they were doing, or they were building a blower motor and ran out of $$.

mmiddle

08-02-2013 12:02 AM

Re: After the math

Quote:

Originally Posted by Lattimer (Post 6200760)

Possibly didn't know what they were doing, or they were building a blower motor and ran out of $$.

2x. Blower motor or stupid.

Zable49

08-02-2013 12:51 AM

Re: After the math

Quote:

Originally Posted by 54belair (Post 6200668)

85 or 86 octane gas?

Nope This is Washington. 87 - 93

Quote:

Originally Posted by Lattimer (Post 6200760)

Possibly didn't know what they were doing, or they were building a blower motor and ran out of $$.

Hey maybe I can talk the wife into a blower. :metal::metal::metal::metal:
Yeah ok thats not feasable on my budget. :( Guess it's new pistons.

WIDESIDE72

08-02-2013 01:21 AM

Re: After the math

Are you sure they are aftermarket postons and not stock dished? What is the bore size?
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Zable49

08-02-2013 01:25 AM

Re: After the math

Quote:

Originally Posted by WIDESIDE72 (Post 6200936)

Are you sure they are aftermarket postons and not stock dished? What is the bore size?
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The engine is bored over +60, and the PO said that he bought the engine from a buddy when he threw a rod in the original 350

Zable49

08-02-2013 01:28 AM

Re: After the math

I guess the question is, should I pick up flat tops or slightly domed... I will be running stocker heads 76cc due to budget.

Lattimer

08-02-2013 07:03 AM

Re: After the math

Quote:

Originally Posted by Zable49 (Post 6200949)

I guess the question is, should I pick up flat tops or slightly domed... I will be running stocker heads 76cc due to budget.

Flat tops with 76cc heads winds up around 8 or 8.5:1. Will run well on regular and act like most stock 350's. With .060" over should be a nice running small block.

From there, you can probably get up to 9.5:1 depending on what you buy. Big limit is the stock heads, and you probably won't make a ton more power going any higher.

I'm almost done building a 327, .030" over with 291 double hump 62cc heads. Flat tops are calculating at 9.6:1 compression. I'm gonna have to run premium in it.

WIDESIDE72

08-02-2013 07:14 AM

Re: After the math

I have run flat tops pistons with old 461 double hump heads on 350's and 383's and a thick head gasket on 87 in the past but you cant run a lot if timing. I forget the details as my brother built it for me but it was a daily driver and remember i would add timing and run 91 octane on ocassion and it really woke up! I later switched to 64cc brodix track1 heads and it was alot more detonation proof due to the heads dissipating the heat better.
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WIDESIDE72

08-02-2013 07:16 AM

Re: After the math

I wouldnt run more than a flat top on the street with iron heads uess you want to spring for the extra octane and imo it wont get you much extra power in return.
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