(please read "self distructing parts" to get up to speed)

Ok so me and my dad got the intake off and it was a mess with the ammount of oil build up.

Once getting it half clean we put it in the van and I drove it to be vatted. Well, the guy at the engine shop called the next day to say there was a crack in the block.

So now me and my dad are going to buy a new engine (aftermarket 350) and reuse the old intake/carb. So, now I'm left with a good set of 305 heads, pistons, spings, and exhaust valves(4 of the intake valves are bent).

Any ideas of what to do with these other than using them as paper weights?

 

Not much call for used 305 parts. Pitch 'em.

 

Exactly... nobody wants any of that. We all throw it in the trash if we can't avoid coming into contact with it.

 

Weeeell, depends.

I'd put it all up on eBay in seperate auctions. There are lots of dumb guys out there rebuilding 305's.

Also, the heads might be desireable depending on the casting. Some of the more preferrable heads will go for $100 US in top quality.

Worth a shot, at any rate.

 

where can i get caaasting #'s?

 

The crank and rods are good for a 350.

 

[QUOTE]Originally posted by Open_Slot
where can i get caaasting #'s? [/QUOTE

Try mortec.com]

 

You might be able to get away with a core on the 305. I did this at Checker Auto. I picked up a 350, and dropped off a 305
Unless they open them up, they can't tell the difference over at Checker.
You can throw it togather, and save a couple hundred bucks on a core...

Ron

 

I know people who have successfully used 305 cranks in 350 motors. It does seem to work OK, however, they are not the same. The 305 crank is lighter. I quote from Lingenfelter's book "Modifying Small Block Chevy Engines":

"In mild street applications, the 305 crank can be used with stock weight replacement (350) pistons allowing the rotating mass to be properly balanced. Unfortunately, when high performance rods and/or pistons are added, the weight difference will require expensive "heavy metal" to properly balance the crank. A 305 crank is not the best choice in this case."

FWIW.

 

Exactly, the stroke is the same - that's it.

His book even showed the part numbers where the same, but using a straight edge on the counter weights showed the difference.

Ron

 

Yeah but for a mild all cast engine wouldn't a 305 crank be better? Less weight = less recriprocating mass = more and faster revs? I understand that in a high preformance application a stronger peice is needed but isn't that true anyway?

 

Ya but then you'd have engine vibraation that would take a specaail balancer, no?

Yes, the letter aa on my keyboaard is messed up...

 

not at all. just a lil 350 one. BTW a buddy of mine ran consistant 12.1x on a 350 with a 305 crank - for years.

 

Did he use the rods as well or use the 350 rods?

 

For mild engines it is fine, but the point Lingenfelter was making is with the offset weighting of the 305 crank when used with non-stock parts. The 305 pistons being smaller in diameter weigh a little less, needing less offset weight on the crank. That, as far as I know is the issue. You are right that less reciprocating weight is better for revs, but the offset weight of the crank has to be equal (or close) to the weight of the pistons, rods, rings, etc. That's why we spend extra $$ for balancing.

 

I am not sure what rods he used but I do know that they were lightened alot. BTW he did have the whould assmbly balanced.

 

The difference is not the piston weight, it's the rod weight. 305 rods are thinner than 350 rods, and so require less counterweight to make up for their lower rotating mass.

You don't have to change the rotating balance (counterweights) to make up for a change in reciprocating mass.

A crank is not reciprocating mass, so its counterweights don't affect the engines internal losses that much. Problem is, to use the 305 crank, you also have to use the weaker 305 rods.

You could build a 350 with a 305 crank and a set of 305 rods, as a set. Although for any kind of real power, the weaker 305 rods are a gamble. You cannot mix 350 cranks and 305 rods, or vice-versa. You can hang any piston you want on the end of any rods you want without affecting the rotating balance, as long as all of them weigh the same.