fk8x vs fk4x

[Jon]

We found out that you can make 500 rpms more with the lightweight lifters with the same setup . If you run the FK 87 or 86C for example you can make up to 8000 rpms with 44 intake valves without valve float .

Hi Udo
What kind of springs and spring pressure are you using? How do you know you have valve/lifter floating, listening or examining the parts after?
Please share, eager to learn.
JHU

[richie]

john,the point here is also by going to a light lifter the existing springs have an easier time,lighter lifter = less spring pressure,
problem goes away?

Yes that's fine in theory. As most don't even know what spring pressure to aim for, guessing how much they can reduce it is a double guess.
I talked with our friend Johannes of JPM yesterday, and he says its better with to much than to little spring pressure. After many hours on the cam analyzer he knows how tough the FK46 are, and how kind the FK89 is (for the lifter).
Btw he uses whatever lifters/ cams and have never had a problem.   

Agreed,my point was people have a spring combo that is marginal and the lifters fail,then swap to ceramics and the lifter problem goes away,then they claim the lifter is the 7th wonder of the world,when reality is they just helped the valve train by saving weight and now are getting away with the spring pressure,I have my own ideas and parts that work for me,no guarantee they will work for anyone else though,some people can break an iron bar in a sand box   cheers richie,uk

[Udo]

We found out that you can make 500 rpms more with the lightweight lifters with the same setup . If you run the FK 87 or 86C for example you can make up to 8000 rpms with 44 intake valves without valve float .

Hi Udo
What kind of springs and spring pressure are you using? How do you know you have valve/lifter floating, listening or examining the parts after?
Please share, eager to learn.
JHU

Hi
I use Gene Berg single , inner and outer springs , next step is manley chevy style and the biggest are K-800 . You can hear the valve float most in 1. gear. We have this by type4 engines that run big heavy valves . But the lifters are ok after this. I never replaced one.

Udo

[Peter]

i guess i ll go for an fk10  or something similar then; changed my mind again
or i have to stop eating hot meals at work and save some more

[cbigpwr]

I think the difference between the 80 series and the 40 series is the overlap. If you have a really good flowing head you can reduce the overlap, make more power, and the motors drive smoother. I have run the 40 series with big rocker (.700 lift) and they drive really nice. but boy do they run good! I ran one in a Ren Kafer type street car and ran the first 11 second pass @ Las Vegas Raceway five years ago. Also ran a 46 in our Super Street car (10:30 @ 130) Suprising it was easy on the cam (never went flat) The 40 series is the latest Cam technolgy; I think every motor should have one in it!

                                                                                                   Anthony Heads Up Performance

[Cheesepanzer]

Hi
I use Gene Berg single , inner and outer springs , next step is manley chevy style and the biggest are K-800 . You can hear the valve float most in 1. gear. We have this by type4 engines that run big heavy valves . But the lifters are ok after this. I never replaced one.

Udo
[/quote]

Udo,
You mention on your web page that you don't recommend break-in.  Really?  Why not? 

Basically, you can fire up a new engine and let it idle, no concerns?  K800 springs?  What about the cam?  Can you do this with any cam?  CB, Engle, etc...?

This is fancinating to me.  Very cool.
 

[Alan Uyeno]

This year I basically started up my virgin 2332 with my udo's like this:

1) got oil pressure with dual chevy springs, rockers and all. Only took aprox 30 sec !!!
2) looked under the car for oil leaks (none  )
3) idled in the garage disturbing my neighbours
4) adjusted the idle and tweeked the a/f mixture screws
5) then I terrorized the neighbourhood.

No nail biting whatsoever. I've never ever experienced such a low stress feeling while starting up a virgin engine. Oddest experience I've ever felt.

I've recently purchased another set of udo's tool steel lifters (regular weight) I weighed my 2nd set and they were 100grams. I'll be using those in my other 2332. Odd.....how I'm using Udo's while I have 2 sets of NOS schubeks sitting in my parts bin.

I"ll have to see how my fk47 works with my Kroc (darren krewenchuk) SE heads. 2yrs ago with my same exact combo with 2289 CB cam I was running 12.00s in my pumpgas (92 or 94 octane) street car. I'm eager to see what this combo does with a different cam.

[Jon]

What kind of spring pressure do you use Alan? Sounds like a great experience

[Alan Uyeno]

What kind of spring pressure do you use Alan? Sounds like a great experience

Chevy springs from CB performance.

The seat pressure is aprox 150lbs and 350ish at full lift depending on what cam I use. Great thing about chevy springs is that they hold pressure for a very very long time unlike vw od springs.

[Cheesepanzer]

What kind of spring pressure do you use Alan? Sounds like a great experience

Chevy springs from CB performance.

The seat pressure is aprox 150lbs and 350ish at full lift depending on what cam I use. Great thing about chevy springs is that they hold pressure for a very very long time unlike vw od springs.

That is awesome!  I gotta check into these bad boys....