Valve springs for Isky cam in a HS50

[Carlos]

What valve springs (and poundage) are you guys using for your Isky camshafts in your HS engines? (either with Isky's 230 or 220 camshaft @.050" checking)

Are you sourcing them from another engine or are you sticking with the std. springs?
Also what spring seat pressures are you aiming for?

 

[ole4]

I am using springs he sent me with the cam. I sent the stock springs for reference and he sent me ones same diam but stiffer.

 

[Carlos]

Which cam do you have? ... the 230 (he said this is the more popular cam with lift at about .276")
Which engine are you running the cam in?

 

[ole4]

230 in a hs50

 

[Carlos]

Thank you ... that's helpful.

Did you have to machine valve pockets in the head and/or reduce the valve margin to accommodate the lift?
What is the power band like?
Do you have a tachometer on the bike?

 

[ole4]

It's been a while but I think I put it together without a head gasket and the valves did not hit the head so I figured with a stock .040 head gasket I was fine. I installed a old style exhaust valve which is a larger diameter than the later motors like I had. I asked tim to keep the base circle the same or slightly larger so I would wind up with less clearance so I could grind the valves for clearance. I do have a tach and have had it up to about 5K max. It has a torque converter and at 5k it is kinda scary to go any more. I could put a smaller sprocket on but it already wheelies too much and has thrown me and a lot of others off it. Power band is not much different than stock just faster. The torque converter gives so much torque multiplication You can't easily tell the difference. I wanted to play with timing but got onto other projects and it always runs great and starts right up so I've left it alone.

 

[Carlos]

OK I've answered my own question on this ...

What valve springs (and poundage) are you guys using for your Isky camshafts in your HS engines? (either with Isky's 230 or 220 camshaft @.050" checking)

I measured a Tecumseh 31672 valve spring at installed height of .865" and 5x coils @ .085" thick.
To avoid coil bind a minimum of .040" would be safe between coils.

Isky's .275" lift camshaft, definitely needs a spring with fewer coils to accommodate the lift.

Isky's .260" lift camshaft on .008" valve lash would leave .047" between coils.
However the quality of the Tecumseh springs looks dubious, I doubt they would hold their load rating for long, if not break.

Simple solution, order Isky springs for either Isky cam!

 

[cdoublejj]

It's been a while but I think I put it together without a head gasket and the valves did not hit the head so I figured with a stock .040 head gasket I was fine. I installed a old style exhaust valve which is a larger diameter than the later motors like I had. I asked tim to keep the base circle the same or slightly larger so I would wind up with less clearance so I could grind the valves for clearance. I do have a tach and have had it up to about 5K max. It has a torque converter and at 5k it is kinda scary to go any more. I could put a smaller sprocket on but it already wheelies too much and has thrown me and a lot of others off it. Power band is not much different than stock just faster. The torque converter gives so much torque multiplication You can't easily tell the difference. I wanted to play with timing but got onto other projects and it always runs great and starts right up so I've left it alone.

could it do more with sturdy/safe and or billet flywheel?