Fluttering past 6K rpms?
04-18-2007, 11:33 AM
#1
Fluttering past 6K rpms? I just had the car retuned at 14.5 lbs of boost. After we got done I took the car on the road and floored it to 6200 rpms, I noticed at 6K I started getting some kind of fluttering sound and the car felt like it was sputtering within those rpms. Do you guys think I'm possibly getting valve float or does it sound like something else is going on.
I originally ran the car at 10 lbs of boost and didn't have this issue till I jumped it to 14.5 lbs. By looking at the boost gauge it spikes to 14.5 then drops to about 12 lbs.
I originally ran the car at 10 lbs of boost and didn't have this issue till I jumped it to 14.5 lbs. By looking at the boost gauge it spikes to 14.5 then drops to about 12 lbs.
Last edited by JD_Z28; 04-24-2007 at 03:48 PM.
04-18-2007, 12:21 PM
#5
Originally Posted by Juiced
You could be going super rich or super lean causing it to sputter, you could be blowing out the spark, the list can go on for ever.
04-18-2007, 12:36 PM
#7
Originally Posted by pwrtrip75
when i tuned my car it did the same.. fouled the plugs. I changed them and ..DAMN!
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04-18-2007, 12:46 PM
#8
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Originally Posted by JD_Z28
I am sucking in a lot of oil from the turbo. I'm not sure if my damn STS pump is strong enough. I'll check the plugs tonight.
Thats not a good sign, oil dilutes gasoline lowering the octane significantly this can be really bad with 15psi, you can run into huge problems.
Check the plus, what do you have them gapped to and what plugs are you running?
04-18-2007, 01:25 PM
#9
Originally Posted by Juiced
How are you sucking in oil form the turbo? Did you blow the seals?
Thats not a good sign, oil dilutes gasoline lowering the octane significantly this can be really bad with 15psi, you can run into huge problems.
Check the plus, what do you have them gapped to and what plugs are you running?
Thats not a good sign, oil dilutes gasoline lowering the octane significantly this can be really bad with 15psi, you can run into huge problems.
Check the plus, what do you have them gapped to and what plugs are you running?
I'm running NGK TR6's gapped to .30
I'm going to pull the plugs tonight and check for oil.
04-19-2007, 10:16 AM
#12
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Originally Posted by JD_Z28
I just changed the plugs and thats not the problem.
I started noticeing this issue when I put on a manual boost controller, seems to work fine when I run the car on the wastegate spring.
I started noticeing this issue when I put on a manual boost controller, seems to work fine when I run the car on the wastegate spring.
04-24-2007, 03:55 PM
#16
TTT...
I checked all the couplings and their all tight. I just checked with TPIS and they said my valve springs are rated at 650 lift so I don't think its valve float.
Does anyone have an idea what could cause the car to start sputtering at higher rpm's? It looks like the car spikes to 14.5 lbs then drops to 12 lbs after 6K. Like I said the problem only happens with the manual boost controller on, when I take it off and run off the wastegate spring it makes 10 lbs all the way up to 6500 rpms and holds.
Any help is appreciated.
John
I checked all the couplings and their all tight. I just checked with TPIS and they said my valve springs are rated at 650 lift so I don't think its valve float.
Does anyone have an idea what could cause the car to start sputtering at higher rpm's? It looks like the car spikes to 14.5 lbs then drops to 12 lbs after 6K. Like I said the problem only happens with the manual boost controller on, when I take it off and run off the wastegate spring it makes 10 lbs all the way up to 6500 rpms and holds.
Any help is appreciated.
John
04-24-2007, 04:32 PM
#17
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Narrow the problem down first.
What springs are you running, and what are they installed at? You need a lot of spring pressure for FI setups.
If it was leaning out it could pop thru the intake.
What springs are you running, and what are they installed at? You need a lot of spring pressure for FI setups.
If it was leaning out it could pop thru the intake.
04-24-2007, 04:39 PM
#18
Originally Posted by Pro Stock John
Narrow the problem down first.
What springs are you running, and what are they installed at? You need a lot of spring pressure for FI setups.
If it was leaning out it could pop thru the intake.
What springs are you running, and what are they installed at? You need a lot of spring pressure for FI setups.
If it was leaning out it could pop thru the intake.
When I put the boost controller in with it turned down all the way it spikes to 14 lbs then drops to about 11-12lbs and starts sputtering at 6K.
The AFR is right at 11.5 across. I changed the plugs and checked all my couplings.
04-24-2007, 07:13 PM
#20
9 Second Club
Initially you say its a fluttering sound, and now you are saying the car is spluttering ??
Which is it, or is it both ?
The fluttering could be perhaps the compressor is too big for your setup ? ( ie compressor surge ? )
Which is it, or is it both ?
The fluttering could be perhaps the compressor is too big for your setup ? ( ie compressor surge ? )