307 to 403 OLDS

olds307 and 403

olds307 and 403

Geezer
Oct 14, 2008
5,338
113
Melville,Saskatchewan
Don't waste a dime on the stock 4A heads. Mine measured about 86cc and they have a horrible exhaust port. Some 64 to 72 Olds 330(around 64cc) to 350 heads(68 to 70cc) with 2" or 2.07" intake and 1.625" exhaust valves with the bowls opened at a minimum. Better flow and a good compression bump. This will bring your current 7.5 to 8 to 1 compression to around 9 to 1, depending on how far those pistons sit in the hole.
 
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TURNA

TURNA

Geezer
Jul 24, 2009
9,453
113
Socialist NY
Just a cruiser!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
olds307 and 403

olds307 and 403

Geezer
Oct 14, 2008
5,338
113
Melville,Saskatchewan
You did a 2004R conversion on this car, did you not? Make sure a good sized cooler is added. My stock 403 with a 204/214 cam like the 2400 flash stall converter. It was rated at 2000 to 2600 stall.
 
Texas82GP

Texas82GP

Geezer
Supporting Member
Apr 3, 2015
5,239
113
Spring, Texas
Just a cruiser!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Yet the 307 isn't enough.....
 
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TURNA

TURNA

Geezer
Jul 24, 2009
9,453
113
Socialist NY
Yep it will be Olds gold if the swap goes through.

I installed the cooler but the 200C is still in the car

I have a GN 2004r and a D5 waiting to be installed.
 

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