SBC valve Springs installation

[dickeymoore]

I have a small block Chevy 350 engine that is on the engine stand with the heads on it and no intake and I would like to change out the valve springs on the heads I know I have to use compressed air in each cylinder but should each piston be at TDC and will it matter if the intake is off the engine with the air in the cylinders

 

[pontiacgp]

It does not matter if the piston is at TDC cause you have to remove the rockers so each valve is closed. With or without the intake makes no difference to change the valve springs but I find it easier without the intake installed to adjust the valves after the spring change

 

[bracketchev1221]

Bring it to tdc with both rockers closed and then you can put the rockers right back on. And if you lose air pressure the valve can’t fall that far. The intake doesn’t matter.

 

[64nailhead]

Definitely have the piston high enough to keep from losing the valve into the cylinder.

https://www.jegs.com/i/Proform/778/66784/10002/-1

I have one of these - the best $50 I spent to change springs on a SBC with the heads on the motor.

 

[RustBucket]

Definitely have the piston high enough to keep from losing the valve into the cylinder.

https://www.jegs.com/i/Proform/778/66784/10002/-1

I have one of these - the best $50 I spent to change springs on a SBC with the heads on the motor.

can you use this without clearance issues on #7 and #8 while engine is still in car?

 

[64nailhead]

can you use this without clearance issues on #7 and #8 while engine is still in car?

I did in 80 Cutlass on a SBC (327).

You ought to have a valve spring installed height measuring tool as well unless you're swapping a set of pretty much stock springs with a stockish lift cam.

 

[565bbchevy]

I have a small block Chevy 350 engine that is on the engine stand with the heads on it and no intake and I would like to change out the valve springs on the heads

I am curious how you end up in a situation where you have an assembled long block on an engine stand and then decide you want to change the valve springs, is this a used engine, fresh build and why do you need to change valve springs?

 

[Turbolq4]

The engine will rotate as soon as you put air to it. Trying to keep the piston up is going to be a waste of time.

 

[64nailhead]

The engine will rotate as soon as you put air to it. Trying to keep the piston up is going to be a waste of time.

That's a reason for a pressure regulator. Itdoesn't take 120lbs of air to keep the valves in the head. Also a set of vise geips on the flexplate or flywheel will solve that problem as well.

 

[64nailhead]

I am curious how you end up in a situation where you have an assembled long block on an engine stand and then decide you want to change the valve springs, is this a used engine, fresh build and why do you need to change valve springs?

I don't want to answer for the OP, but I got into that situation of ordering the minimum springs that will work for 8-10 psi of boost. It seems that they didn't fair as well at 15-16 lol. Boost is addictive - live and learn