bucking

QWKSNKE · 09-15-2005, 08:56 PM

Well as mentioned in the other thread my driveability is getting a lot better. Been data logging and making MAF changes based off EA a good bit over the last 2 weeks.

The bucking seems to be coming from decelaration. Is this still due to the out of whack MAF curve or I am missing something else?

Disney Lincoln · 09-16-2005, 01:26 AM

I would guess it's from the Dashpot decay rate.

QWKSNKE · 09-16-2005, 07:01 AM

Quote:

Originally Posted by Disney Lincoln

I would guess it's from the Dashpot decay rate.

tell me more

86GT · 09-16-2005, 12:27 PM

It could also come from the spark tables. Look at FN125 to see where the tables switch over. Then look in the spark tables and make sure the transition between the tables is smooth. If the spark jusps or dips drastically it will cause all kinds of bucking.

This took me forever to find.

Disney Lincoln · 09-16-2005, 02:18 PM

I couldn't start to talk about the Dashpot decay and preposistion functions..... I don't understand them well enough to offer tuning advise for them. I just spent a few hours one night going through the Yahoo group and the optlink board reading posts from people smarter than I.

Clint.... care to fill him in?

QWKSNKE · 09-16-2005, 02:45 PM

One key note.....

I never had this problem when the car was tuned with the 42's and 42# univer. Only since I swapped to the 60's and the 55# univer have I started experiencing these problems.

Disney Lincoln · 09-16-2005, 04:00 PM

Then, that would point to a MAF adjustment...

On the dashpot decay I just went in and made the values smaller. Car quit surging. I messed with the preposistion also, but that didn't help me any. The decay rate was noticable.

86GT · 09-16-2005, 04:34 PM

I personally have not played with the decay or preposition yet. I due have a slight bucking, but I think it is due to my spark tables since that was the last thing I messed with.

If the only thing that you changed was the MAF and slopes, then I agree the MAF must be the problem.

93Cobra#2771 · 09-19-2005, 09:32 AM

If it makes you feel better, I still have slight decel bucking issues. I REALLY need to do a little more tuning...

86GT · 09-19-2005, 11:09 AM

I put my spark table back to stock and the problem went away. I am going to do some testing to find out what caused it.

09-15-2005, 08:56 PM	#1
QWKSNKE 3v's are slow Join Date: Dec 2004 Location: Here and There Posts: 17,152	bucking Well as mentioned in the other thread my driveability is getting a lot better. Been data logging and making MAF changes based off EA a good bit over the last 2 weeks. The bucking seems to be coming from decelaration. Is this still due to the out of whack MAF curve or I am missing something else? __________________ 2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy

09-16-2005, 12:27 PM	#4
86GT Member Join Date: Mar 2005 Location: Sacramento California Posts: 449	Re: bucking It could also come from the spark tables. Look at FN125 to see where the tables switch over. Then look in the spark tables and make sure the transition between the tables is smooth. If the spark jusps or dips drastically it will cause all kinds of bucking. This took me forever to find. __________________ EEC Analyzer A9M, TwEECer, 306ci, 73mm C&L w Tuner Tube, Cobra Intake, 42# inj, Edelbrock 6037, E303 cam, 155 fuel pump, FPR, 70mm TB, E-Fan, 3.55 gears, Powerdyne 9psi actual 5psi...way more.

09-16-2005, 02:18 PM	#5
Disney Lincoln Senior Member Join Date: May 2005 Posts: 290	Re: bucking I couldn't start to talk about the Dashpot decay and preposistion functions..... I don't understand them well enough to offer tuning advise for them. I just spent a few hours one night going through the Yahoo group and the optlink board reading posts from people smarter than I. Clint.... care to fill him in?

09-16-2005, 02:45 PM	#6
QWKSNKE 3v's are slow Join Date: Dec 2004 Location: Here and There Posts: 17,152	Re: bucking One key note..... I never had this problem when the car was tuned with the 42's and 42# univer. Only since I swapped to the 60's and the 55# univer have I started experiencing these problems. __________________ 2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy

09-16-2005, 04:00 PM	#7
Disney Lincoln Senior Member Join Date: May 2005 Posts: 290	Re: bucking Then, that would point to a MAF adjustment... On the dashpot decay I just went in and made the values smaller. Car quit surging. I messed with the preposistion also, but that didn't help me any. The decay rate was noticable.

09-16-2005, 01:26 AM	#2
Disney Lincoln Senior Member Join Date: May 2005 Posts: 290	Re: bucking I would guess it's from the Dashpot decay rate.

09-16-2005, 04:34 PM	#8
86GT Member Join Date: Mar 2005 Location: Sacramento California Posts: 449	Re: bucking I personally have not played with the decay or preposition yet. I due have a slight bucking, but I think it is due to my spark tables since that was the last thing I messed with. If the only thing that you changed was the MAF and slopes, then I agree the MAF must be the problem. __________________ EEC Analyzer A9M, TwEECer, 306ci, 73mm C&L w Tuner Tube, Cobra Intake, 42# inj, Edelbrock 6037, E303 cam, 155 fuel pump, FPR, 70mm TB, E-Fan, 3.55 gears, Powerdyne 9psi actual 5psi...way more.

09-19-2005, 09:32 AM	#9
93Cobra#2771 The Kocky One Join Date: Dec 2004 Location: Yeah, but those cutters won't bust any walnuts.â„¢ Posts: 1,948	Re: bucking If it makes you feel better, I still have slight decel bucking issues. I REALLY need to do a little more tuning... __________________ *For Sale: Reproduction Window Stickers, 87+ Mustangs, Cobras, Lightnings, and HD F150!* Richard White 93 Cobra Kocky will be back!

09-19-2005, 11:09 AM	#10
86GT Member Join Date: Mar 2005 Location: Sacramento California Posts: 449	Re: bucking I put my spark table back to stock and the problem went away. I am going to do some testing to find out what caused it. __________________ EEC Analyzer A9M, TwEECer, 306ci, 73mm C&L w Tuner Tube, Cobra Intake, 42# inj, Edelbrock 6037, E303 cam, 155 fuel pump, FPR, 70mm TB, E-Fan, 3.55 gears, Powerdyne 9psi actual 5psi...way more.