305 and 350 compatability
10-12-2000, 06:10 PM
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Car: 1992 Camaro RS
Engine: 355
Transmission: th400
Axle/Gears: 3.89
305 and 350 compatability
I plan on purchasing a 350 4 bolt block from SDPC. I currently have a 305 in my RS and I had read that the stroke on the 350 and the 305 are the same, so does that mean that I can reuse my crank? I also intend to keep my TBI and also plan to jet up my NOS kit to put out about 250 hp. I already know I need forged pistons.
10-12-2000, 07:17 PM
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the cranks are different. You need a new crank (or a used one--just get it checked) and rods. The heads will work but not as well as another set could.
Jeremy
------------------
92 Z conv
5-spd B&M
alston SFC, few mods, some free, some not
Jeremy
------------------
92 Z conv
5-spd B&M
alston SFC, few mods, some free, some not
10-12-2000, 09:39 PM
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Car: was: 1984 Camaro Z28
Engine: was: L69
Transmission: was: 700-R4
Actually the cranks are the same, BUT balanced differently (due to smaller 305 pistons). The way to tell if you have a 305 crank from a 350 is, see the notches on the crank counter-weights. Those are reliefs for weight (IIRC) and if you can lay a straight edge on them that touches all of them without any gaps (or very little) then you have a 305 crank. You cannot do this with a 350 crank, the reliefs are offset. JFYI 
You really don't want to use the 305 crank, not because it could be weaker (that false), but because you will have to add mallory weight (read as $$$$) to it to compensate for the added 350 piston weight. Unless of course you are in a class that requires cast OEM cranks, and you are using light weight pistons, but I doubt this is the case.
------------------
George P. Lara
1994 Z28 LT1 T56
1984 Z28 High Output
Member: SCCA, SCFB, SC3GFB
[This message has been edited by MRZ28HO (edited October 12, 2000).]
You really don't want to use the 305 crank, not because it could be weaker (that false), but because you will have to add mallory weight (read as $$$$) to it to compensate for the added 350 piston weight. Unless of course you are in a class that requires cast OEM cranks, and you are using light weight pistons, but I doubt this is the case. ------------------
George P. Lara
1994 Z28 LT1 T56
1984 Z28 High Output
Member: SCCA, SCFB, SC3GFB
[This message has been edited by MRZ28HO (edited October 12, 2000).]
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