what would valve float feel like? or symptoms

Yaj Yak

Gladys
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aight on my turboo'd car. when i drive it...

it feels like its almost misfiring... or soomething along those lines at 5k + rpm... but normally the 2-3 shift... not the 1-2... that i can notice at least.

i have 147k miles on all stock valvetrain. stock engine.

it sounds llike its almost hitting a rev limiter or something...

im seeing around 10psi...


or could it be spark blowout?
 

my97gtp

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valve float im sure when i had the rockers on 8psi was about the max i could get removed then and could go to about 12 psi and it brakes up does it pull hard when you shift to third? mine lags alot from about 5k-5.8k then shifts to 3rd and pulls hard as shit for 10psi at least. im hoping the 130's and a long rod fix the prob
 

Mike K

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valve float im sure when i had the rockers on 8psi was about the max i could get removed then and could go to about 12 psi and it brakes up does it pull hard when you shift to third? mine lags alot from about 5k-5.8k then shifts to 3rd and pulls hard as shit for 10psi at least. im hoping the 130's and a long rod fix the prob
Yeah that's pretty much exactly where I'm at right now but I'm running stock rockers and higher shift points. At the top of the gear you can feel it slow down but as soon as it goes from 2nd to 3rd it launches...

Rockers and 105's are coming soon.
 

Yaj Yak

Gladys
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It's a common problem on the turbo cars. What are your shift points set at?

43mph/5800rpm

83mph/5800rpm

should I change em?


valve float, there's pressure on both the intake and ex sides to counter spring pressure

are you saying you think i have valve float?

valve float im sure when i had the rockers on 8psi was about the max i could get removed then and could go to about 12 psi and it brakes up does it pull hard when you shift to third? mine lags alot from about 5k-5.8k then shifts to 3rd and pulls hard as shit for 10psi at least. im hoping the 130's and a long rod fix the prob

whoa. jay. whoa. i don't know what you just said.

I had problems with spark blowout at .40 gap on my car when Bob did it this week and i'm seeing about 11psi. I would look into that, he it sounded like it was bouncing off the rev-limiter and breaking up. He re-did them to .32 and now it runs great.

im prolly gonna go smaller to see if it changes it.



Yeah that's pretty much exactly where I'm at right now but I'm running stock rockers and higher shift points. At the top of the gear you can feel it slow down but as soon as it goes from 2nd to 3rd it launches...

Rockers and 105's are coming soon.

alright. with that description. im thinking that i have spark blowout... cuz my car doesnt do that- mine when it happens- seems to "chug" after 5k rpm.
 

my97gtp

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i guess thats what i get for watching tv and trying to post at the same time what i was trying to say was when the rockers were on i could get to about 8psi till it would brake up so bad i would loose power, i then removed the rockers can now get to about 12psi before it brakes up bad plugs are gapped at .032, just need to order gaskets now so i can get the cam installed mine feels and sounds like a rev limiter sometimes, its worst in second from 5k to 5800 but when it shifts to 3rd it pulls like mad
 

Turbocharged400sbc

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eric pushes over 14.7psi on the whipple and his are gapped at .045 and regularly saw 6500rpm and several 7k hits and never saw an issue...though that's with 150lb springs

if your getting spark blowout at 10psi you have one helluva weak coil, plenty of times i've seen valve springs that have weakened...remember eric had the whipple with the VS and he broke a stock 35k 05 L32 valvespring that damn near destroyed the engine.
stock is good for stock, go ahead and regap them, but do it in coil pairings, then test drive, and move to the next coil pairing, repeat and see if maybe you have a weak coil
 

Yaj Yak

Gladys
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here are two pics of scans.

hpt2.jpg


hptuners-1.jpg
 

10sec

I haz dat teddy bear smile.
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60's max out fast AF with E85. You can make 400whp easy on a stock motor, no need for a cam and reliable. You can destroy transmissions all day with a stock motor, IDK why everyone goes nuts with cams and shit. Stock motor, good valve springs and a 60-ish trim turbo set up to spool quickly. Done. Easily an 11sec car which is more than any junk ass trans can take anyways.
 
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