Jrp1978

iTrader: (10)

I have horrible buckinng 1200 to 1900 rpm ?

ONEBADASSWS6

Vehicle?? Engine??

Is the check engine light on??

When was the last time it was tuned up??

Need a bunch more info.

ssfast99

iTrader: (3)

i would say a big cam and or a crappy tune. but more info to pinpoint.

mikey67

I had an '88 Beretta years ago that hadn't had GM's speed density upgrade. I had this problem and the maf was bad, no SES. Not the same car but worth checking.

Jrp1978

iTrader: (10)

ls6 stg 2.5 heads

trv 3 cam .643 .598 232 234 duration

headers

ud pulley

lid

p p tb

partick g mail order tune

The thing is there are day where is wont do it ?

Demon Of Dreams

iTrader: (3)

it's the nature of your cam and tune... mine does it on colder days but when its a bit more humid out it drives perfectly fine

ssfast99

iTrader: (3)

Tune.

TheLS1Kid

iTrader: (12)

Exactly how mine is.

92slowmaro

iTrader: (22)

put some gears in it. it will make your car perform better and will up your rpms so it wont buck as bad. and get a dialed in tune.

3.4camaro

iTrader: (1)

too much ignition advace and/or too much airflow.

Jrp1978

iTrader: (10)

Its got 410 and a m12 tranny


Is it possible that this throtttle body i have that you can see light all the way around the blade when it is closed is doing this?

92slowmaro

iTrader: (22)

well that may or may not be causing the problem. but you should get that fixed. and then have your tune dialed in

Jrp1978

iTrader: (10)

so what is it timing or fuel? At anytouch of the throttle the timing read 40.4 until wide open and it reads 28.8

shoemike

iTrader: (25)

edcmat-l1

iTrader: (10)

Theres part of your answer right there.
With the bigger cams, reducing the low load low rpm timing helps the bucking a bunch.
Stock, the timing in that range is 41 deg. I start with that range reduced to about 38 degrees, and have run em as low as 34.
You also have to make sure the fueling is close too. If the trims have to adjust a bunch it'll make it worse. You'll always a little bit of low speed surge/buck, but if tuned right it will be real close to stock. You can get a bone stock one to buck and surge if you lug the motor low enough.
Do you have tuning and logging software, or did you send him your PCM?

Jrp1978

iTrader: (10)

so i took some timing at 1k to 1800 out and no bucking and now it wants to hang rpms at 1500 and stay there until i stop.

Demon Of Dreams

iTrader: (3)

i still fight with mine sometimes with that... for mine, i'm either running too rich or theres too much air getting in, because it doesn't go away until I'm at a full stop for over a second or two, when it does it

FoolZRacing

iTrader: (1)

sometimes when its hanging you can adjust the throttle follower multiplier and decay rate and itll help the hanging idle.

LS1HIGHLIFE

iTrader: (8)

Mine does this also and was told it was in my tune.... I'm having her looked at again real close in a few months to rectify some tuning issues I'm having. I'll post up what the guy finds when I get it done.

m6speed

iTrader: (11)

it took a while of fine tuning to finally get rid of most of the bucking on my car with that same cam, pain in the ***..