Ion

Hi guys..

Im rebuilding this 425 Toro engine, casting# 389244D.

I got the short block with C-heads, but these heads were cut and inserted Chevy big block valves in, and I have to figure all the geometry before I can use those.
Instead Ive currently stuck som Ga-heads on this engine, and Im in desperate need of the pushrods and rocker bridges for the 425 Toro engine. As Ive understood this engine has a differen lifter angle and lifter diameter, and requires other pushrods and bridges? I need those. Lifters followed the engine luckily.
I found out when I tried to use the pushrods and rocker bridges and rockers from a 1974 Toro 455 engine, didnt work. Gonna rebuild this next, but the 425 is the engine I want to use.

Can anyone help, where to get these, or have something to sell me?

Thanks

Oldsmaniac

The C heads and G heads and 74 Toro heads all used the same rocker arms and bridges stock. Toro heads already have big valves, Intake so I don't know what was done to them. Pushrods are the last thing to order once heads, lifters and rockers are installed. Then you can measure or see what pushrods you need. Rockers and bridges are available new from most auto stores although the bridges may be different, single instead of two in one.

Ion

Okey, thanks. I read somewhere that the 425 Toro with 39 degree angle had other taller bridges, but one reads alot of different stuff everywhere.
Then I have the bridges, rocker and lifters, only have to measure the correct rod length then..

joe_padavano

The pivot assembly is dimensionally the same on every 1964-1990 Olds V8. Only the pushrod length changes. Your best bet is to get a pushrod length checker and figure out exactly what you need for your combo. In engines with stock valves and heads, the 1965-66 RWD 425s used 9 5/8" pushrods. The 66-67 Toros used 9 7/16". The 67 RWD 425s used 9 21/32". The 455s used 9 37/64". Again, this all assumes a new factory short block and heads with stock valve stem heights and a steel shim head gasket.

Oldsmaniac

Except the 64 330 with the shaft mounted rockers.

Ion

So then, if I wanted to utilize the C-heads I have, that has been modified with big Chev bigblock valves, I just need to cut the valves down to "stock" Olds length?
I bet it isnt that easy is it?

joe_padavano

Correct. I meant to write 65-90, but force of habit made me write 64 instead.

edzolz

Take a straight edge and place it across the tops of the valves. If they are all the same, the valves do not need to be cut. If the intakes are longer, the heads will have to be taken apart to cut the length of the valves.

Ion

These valves has never been in these heads before.
They have been cut and fittet to the new seats.
Length wise they are not cut, universal with double grooves for the retainers now. Have to figure out the length over the valve spring seat (isnt that correct?) they should be for the right geometry..