Car starts popping/stuttering at 5,900 rpms... is it running lean or valve float?
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Car: Junk
Engine: Junk with nitrous
Transmission: Junk with gears
Car starts popping/stuttering at 5,900 rpms... is it running lean or valve float?
Been tweaking on my girlfriends new car (85 trans am, LG4 305, 262 cam, edle intake, headers, 3.42 gears, holley 600 carb) and the holley carb on there was tuned by a guy that really doesn't know jack about holley's........I"ve been too lazy to open it up and see how badly he ****ed it up, but I got it fixed so that now it doesn't bog.....problem is, sometimes when I race people the motor will pop/bog/stutter out the exhaust like its either running out of gas or just something's wrong. I figure its either valve float or running too lean. The motor pulls all the way to 6,000 rpms, but right when it gets that high its starts popping and really slows the car down. The valve train on the motor is probably the original 160K 1985 305 stuff since the guy that did the comp 262 cam said he didn't install performance valvesprings when he did the swap. Any ideas?
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Car: 4
Engine: 6
Transmission: 5
Popping in the exhaust = raw fuel passing through the motor
Popping in the intake = lean
Doesn't sound to me like it's lean.
I'd guess you have a combination of valve float and poor ignition. If one of those XE cams is under a set of worn-out stock valve springs, it's a time bomb, just waiting to drop a valve at that kind of RPMs.
Change the valve springs first, since that's an obvious, known defect. Then go from there.
Popping in the intake = lean
Doesn't sound to me like it's lean.
I'd guess you have a combination of valve float and poor ignition. If one of those XE cams is under a set of worn-out stock valve springs, it's a time bomb, just waiting to drop a valve at that kind of RPMs.
Change the valve springs first, since that's an obvious, known defect. Then go from there.
#3
Your old weased out valve springs are the cause of your problem. My recommendation would be to pull the junk 5.0 out and put in a healthy 5.7. quit foolin' around with slow weased out junk. Or else spend the couple of hundred to put in new springs. the choice is yours.
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Car: Junk
Engine: Junk with nitrous
Transmission: Junk with gears
Originally posted by savage_racing
Your old weased out valve springs are the cause of your problem. My recommendation would be to pull the junk 5.0 out and put in a healthy 5.7. quit foolin' around with slow weased out junk. Or else spend the couple of hundred to put in new springs. the choice is yours.
Your old weased out valve springs are the cause of your problem. My recommendation would be to pull the junk 5.0 out and put in a healthy 5.7. quit foolin' around with slow weased out junk. Or else spend the couple of hundred to put in new springs. the choice is yours.
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Car: 2002 Harley Nightrain
Engine: twin cam 88ci
Transmission: manual
you and your girlfriend won't be beat'n it too much longer with those springs in there.. Spend a days pay and another day of your time and put some springs in there and then see what that motor can do.
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Car: 2009 Volvo V50 R Design
Engine: 2.0 turbo diesel
Transmission: 6 speed auto
Axle/Gears: yes, both
hell, the redline starts at 5000 , so six is really thrashing it!
if the top end dont blow then the bottom prob will
if the top end dont blow then the bottom prob will
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u get like a pop/bog when ur trying to give it gas right? is the engine hot by then? if so replace the ignition control modula. i had the same probalem with my car. i didnt know it was that untile after i put a new fuel pump, fuel filter, spark plugs, coil, and a new edelbrock carb on. and it still gave me that problem even at low rpms and on day it died on me and well we replaced the control modula at work and to our surprise it was old and dirty and looked to be the only thing not replaced when everything else in the distributor was but after we took it out it only had 2 spots of that heat sink stuff on it. so we replaced it and put a crap load of the heat sink stuff on it and well too this day i have not had a problem since.
and now after driving for 15-20 mins i can still get on it with out worriing of anything poping or boging or anything.
and now after driving for 15-20 mins i can still get on it with out worriing of anything poping or boging or anything.
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Car: Junk
Engine: Junk with nitrous
Transmission: Junk with gears
Originally posted by philoldsmobile
hell, the redline starts at 5000 , so six is really thrashing it!
if the top end dont blow then the bottom prob will
hell, the redline starts at 5000 , so six is really thrashing it!
if the top end dont blow then the bottom prob will
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