Rpm question

[Todi]

Can some one tell me how much Rpm a pair of CB Wedge Port Heads 44x37,5 will do direct out of the box, no make over. I have a Fk87 cam.

[Bewitched666]

Damn thats a ruff one but i dont think heads will have influence on your rpm.
Rpm depends on the rotaing mass like crank,cam etc. But i think your cam can hit in the 8000 rpm

[airstuff]

the springs will suffer,and wil get softer,do you have normal springs and valves,or do the heads coem with their LS-1 valve/spring package.

FK-87 creates a lot of lift,for VW lenght springs.

[Todi]

the springs will suffer,and wil get softer,do you have normal springs and valves,or do the heads coem with their LS-1 valve/spring package.

FK-87 creates a lot of lift,for VW lenght springs.

The heads I have is 94 bore and what I can see you will only get LS-1 with 90,5/92 bore, or am I wrong..... How about some Chevy springs then? 

[airstuff]

the springs will suffer,and wil get softer,do you have normal springs and valves,or do the heads coem with their LS-1 valve/spring package.

FK-87 creates a lot of lift,for VW lenght springs.

The heads I have is 94 bore and what I can see you will only get LS-1 with 90,5/92 bore, or am I wrong..... How about some Chevy springs then? 

You must know how much you payed for the,then you know what is included.

Some Chevy springs would do better with this cam,but here are people who can tell you exactly what you need.

Come on guys

[BeetleBug]

Without the LS1 package you`re on the limit and close to coil bind when you have reached the correct pressure. And no, you do not need Chevy springs or K800`s. The FK87 is easy on the valve train and do not need monster spring pressure.

[Ohio Tom (DdK)]

With the 87 cam, the lobes have very gentle ramps. As long as you keep the valve lift reasonalbe, you can make the springs last a little while.
However, even with worn springs, you should still see 6,800-7,000rpm before valve float.

[JS]

Those springs wear out kinda fast, I have revved mine to 8000 a couple of times, normally I shift at 7000 at the drags.
After 2000km on the street and a few drags (one short summer) there were only 110lbs left in them...

[Todi]

So it seem to be a good idee to change the springs I have now in to my chevy ones... Can point out that the engine I have is for dragracing only!   

[Shubee2 (DSK)]

I would not use them right out of the Box First off do A 3 Angle valve job on them and check for coil bind  depending on cam used and spring seat pressure  before just bolting a set on..

[Todi]

I would not use them right out of the Box First off do A 3 Angle valve job on them and check for coil bind  depending on cam used and spring seat pressure  before just bolting a set on..

Sorry for my bad english, but coil bind ??

[j-f]

I would not use them right out of the Box First off do A 3 Angle valve job on them and check for coil bind  depending on cam used and spring seat pressure  before just bolting a set on..

Sorry for my bad english, but coil bind ??

There is a thread where Jim explain how to check coil bind. It's the clearance you have between each spring coil.

[JS]

How long can you expect valve springs to last in a high hp application on our engines before loosing a lot of tension? I see the top fuel guys check them after every run?

[BeetleBug]

Try this;

Take out one or all your new, unused springs and messure them, then press them all the way to coil bind and messure them again. Do not be suprised if you have lost spring pressure. Crappy springs are a problem.