Could I be Floating the Valves?

[TT/Ameasap]

When my car spins the tires, my RPM's go to 6000-6100 and it seems like im hitting a rev limiter. My tire marks skip in the road...like 20ft of rubber then nothing for 10ft then 20ft of rubber and so on to about 80-100ft.
Car has always done this with different setups. When I get traction at the track, it is perfectly fine.

 

[Chuck Leeper]

What's the limiter in the chip set for? [If there is one.]
Wheel hop?

 

[TT/Ameasap]

I don't believe there is a limiter. Happened with alky chip too and I know that doesn't have a limiter. Don't think it's wheel hop. The car noses over at the time of skipping like its cutting fuel.

 

[PSID6]

Never had it happen to a 3.8 V6. But did build an LS v8 a few years ago that I put on an engine dyno that had some bad valve float and it sounds very much like a limiter just a lot more violent.

 

[TurboTdr3.8]

Do you have any logs when its happening , my car was doing like it had rev limiter and it does not and it was the valve spring also floating , chased that problem 6 months till I figured it out, on my logs it would go bad rich and kr when it happened .

 

[TT/Ameasap]

Yes I have logs. I get false KR when it happens.
Now, if this IS floating valves, wouldnt my RPM's go through the roof if I corrected it?

 

[TurboTdr3.8]

wouldnt my RPM's go through the roof if I corrected it?

RPM`s will be a limited factor to your head flow and camshaft design I would think . It should stop your so called rev limiter for sure if you get the valves in order from floating .

 

[Mike Licht]

tell us more about the cam, we have springs that will fix it if need be
Mike

 

[TT/Ameasap]

tell us more about the cam, we have springs that will fix it if need be
Mike

Ya, I'm not sure it's valve float from everything I have read or seen on YouTube. This is more of an ignition cut if you will. The car loses power for a second and comes right back.
Here's the specs to the cam.

 

[Mike Licht]

That lobe is super aggressive I have used it, I know you dont want to change the springs but I am going to bet you have valve float. What springs did weber use? Setting up the heads for that cam is tricky.
Mike

 

[TT/Ameasap]

It doesnt say specifically which ones they used...but if you know this combo, I will trust you in thinking this really could be valve float Mike.
Lemme know what kinda deal you can get me to do everything including tools if necessary.

 

[Mike Licht]

call me tomorow so we can discuss this a bit please. I would like to do this right rather than just sell you some parts
Mike

 

[dr_frankenstein]

why did they marke your cam card as Odd Fire?

 

[TT/Ameasap]

why did they marke your cam card as Odd Fire?

roller cams are odd fire as I have seen

 

[Mike Licht]

The cams are all even fire but the billet blanks have odd fire noses on them so they list them that way on the card, not sure why

 

[bison]

I wouldn't use those lobes with less than 170lbs on the seat and with a 1.55 ratio rocker. If higher ratio I'd use even more seat pressure. Setting iron heads up for that lobe is a little bit of work as mike stated but can be done


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[StageII86]

When your tires are braking loose the springs are experiencing different harmonics and they are likely floating hard. We used to have very aggressive LS cars that would act similar with silly large cams. With traction or in upper gears (slower pull), we could get the power and RPM, but lower gears we would have issues. Problem is that once you do that a few times you've likely killed the springs, lost tons of seat pressure, and you may quickly wind up with dangerously low pressures all around. The remedy there was A) realizing that you didn't always need a square lobe to go fast, and B) the valve spring technology caught up!

 

[TT/Ameasap]

Thanks guys! I will get in contact with you later for more info and purchase.