What valve springs : V-Twin Forum: Harley Davidson Forums

atengnr · 01-22-2005, 10:26 AM

What valve springs should I install on SE Heads for good longevity, up to 550 lift. Ive heard that the springs in the SE Heads are too stiff for good valvetrain life....Your thoughts?

Thanks

HDMD88 · 01-22-2005, 11:11 AM

Quote:

Originally Posted by rpajewsk

What valve springs should I install on SE Heads for good longevity, up to 550 lift. Ive heard that the springs in the SE Heads are too stiff for good valvetrain life....Your thoughts?

Thanks

The sspring pressure is related to the cam you are using....saying that, what cam do you have: Duration anad brand.
S/E has three sets of springs....which one do you have?

atengnr · 01-22-2005, 11:35 AM

I have production screamin eagle performer heads. I believe they are 175 installed force springs with .575 max lift.

I currently have ss510G cams (238, 252), but may switch to a andrews 55 or ss570G in the future.

HDMD88 · 01-22-2005, 11:56 AM

Quote:

Originally Posted by rpajewsk

I have production screamin eagle performer heads. I believe they are 175 installed force springs with .575 max lift.

I currently have ss510G cams (238, 252), but may switch to a andrews 55 or ss570G in the future.

The 175 seat pressure spring is a double wound spring with a flat dampner spring in between the two springs. This spring has 450 lbs pressure at full open, that might be a little much for your 510 lift but its good for the 252 duration. Your springs are in the middle area for S/E spring kits. There is one set that is good up to .620 lift but the seat pressure is only 150 lbs and full open is 345 lbs. And I believe you can get by with these with no problem. The high end set is good for .650 lift with a seat pressure of 195 lbs and full open pressure is 505 lbs. If you are ever in doubt what pressures you need, call the cam manufacture and they will gladly tell you what you need to run with their cam.

atengnr · 01-22-2005, 12:05 PM

Am I sacrificing significant valvetrain longevity with the extra spring force? Are the softer springs you mention stiff enough if I use a SS570G cam?

HDMD88 · 01-22-2005, 12:13 PM

Quote:

Originally Posted by rpajewsk

Am I sacrificing significant valvetrain longevity with the extra spring force? Are the softer springs you mention stiff enough if I use a SS570G cam?

I have used them with a 240 duration and a .590 lift with out a problem.

atengnr · 01-22-2005, 03:30 PM

Can I use the factory springs (175 lb) in the SE Heads with ss 570G or will that be eating away too much valvetrain life??

HDMD88 · 01-22-2005, 04:26 PM

Quote:

Originally Posted by rpajewsk

Can I use the factory springs (175 lb) in the SE Heads with ss 570G or will that be eating away too much valvetrain life??

Yes you will be fine with the 175 springs

atengnr · 01-22-2005, 10:12 PM

HDMD88 - I ordered he softer springs you recommended. Thanks for your help.

HDMD88 · 01-23-2005, 09:14 AM

Quote:

Originally Posted by rpajewsk

HDMD88 - I ordered he softer springs you recommended. Thanks for your help.

Wise dessision...thank you

LilEvilAmy · 01-26-2005, 12:47 PM

The #18223-98 springs will not be sufficient for the S&S 570 cams, larger heavier valves, and heavier/adjustable pushrods. When in doubt you are always better off to err on the side of safety. You will not significantly wear your valvetrain at a faster rate with the supplied #18273-00 springs. It would be much worse to have your valves make contact with each other or the piston. Harley supplies those springs with those heads for a reason.

HDMD88 · 01-26-2005, 04:54 PM

Quote:

Originally Posted by LilEvilAmy

The #18223-98 springs will not be sufficient for the S&S 570 cams, larger heavier valves, and heavier/adjustable pushrods. When in doubt you are always better off to err on the side of safety. You will not significantly wear your valvetrain at a faster rate with the supplied #18273-00 springs. It would be much worse to have your valves make contact with each other or the piston. Harley supplies those springs with those heads for a reason.

Amy first of all welcome to the fourm. The cam this man is using is a .510 lift not a .570. Even at that I have used the softer 345lb spring with .590 lift and it works fine.....I don't always use this spring but it can be used. I am not new to building motors, and I agree if your not sure go with stronger set. The HTCC heads (which come with the 18273-00 springs) are usually used with the 211, 256, and 257 cams which require the heaver springs....but for a .510 he can get away with the lighter springs. It takes horsepower to open the spring, the stronger the spring the more horsepower is used up....its called mechanical losses, and I'm sure you know that. Springs are rated for a cam not a head, even though you have a good point with the heaver valves.
You have a good head on you Amy, keep up the good work.

LilEvilAmy · 01-26-2005, 05:38 PM

Hi, hdmd88! Thanks for the welcome.

Quote:

Springs are rated for a cam not a head

Springs are not rated for a cam, either. The proper springs are chosen based on application (rpm range, cams, valvetrain, etc.). The point I was trying to make is that he stated in an earlier post that he was going to be switching to either the TW55 or S&S 570 cams in the future. Why should he waste $$ by changing to lighter springs when he'll have to change them back later. Even S&S recommends 160 pounds of seat pressure with the gear drive system, and higher seat pressure is required for higher performance levels. The lighter springs won't be sufficient at the higher rpm that the SE heads will allow the engine to perform to. We've seen these heads that we've ported, with the supplied springs, float the valves with a .560 cam. It wasn't pretty. I just think he's wasting his money and time by switching to springs that may not even be enough for the 510's, much less future upgrades. I still say that its better to be safe, with $130 still in your pocket, than sorry.

atengnr · 01-26-2005, 10:42 PM

Quote:

Originally Posted by LilEvilAmy

Hi, hdmd88! Thanks for the welcome.

Springs are not rated for a cam, either. The proper springs are chosen based on application (rpm range, cams, valvetrain, etc.). The point I was trying to make is that he stated in an earlier post that he was going to be switching to either the TW55 or S&S 570 cams in the future. Why should he waste $$ by changing to lighter springs when he'll have to change them back later. Even S&S recommends 160 pounds of seat pressure with the gear drive system, and higher seat pressure is required for higher performance levels. The lighter springs won't be sufficient at the higher rpm that the SE heads will allow the engine to perform to. We've seen these heads that we've ported, with the supplied springs, float the valves with a .560 cam. It wasn't pretty. I just think he's wasting his money and time by switching to springs that may not even be enough for the 510's, much less future upgrades. I still say that its better to be safe, with $130 still in your pocket, than sorry.

What speed did the valve float at? I dont plan to exceed 6200 rpm...I hear what you say, but I must point out that those springs have 450 lbs of force at .575 lift! That is exactly double the force of stock spring at its max lift. To me that sounds like 225 lbs of extra loading on the valvetrain at max lift!! Directionally, I would think that means significantly more valvetrain wear -

Youre right, I would like to keep my options open for future cams maybe a .550 cam.