Hopping

Sled-pulling, Drag results, Dyno results

Moderators: Greenleaf, KTA, BC847, Richie O

Hopping

Postby ahale2772 » Wed Mar 02, 2011 8:49 am

so last year I pulled 2 times (three runs each pull) my truck had 33/12.5 BFG, 3.07 gears, 5 speed in 4 low 2nd gear. Traction bars from the tranfercase crossmember to the rear ubolt plate.

Both pulls I ran my hitch at about 18 inches the first pull and somewhere neer 20 the next pulls.

at 18 inches the truck pulled smooth as glass but didnt run as fast, at 20in the truck would hop really bad off the line unless I let out a bit then slowly brought the rpms back up, once it hooked again it felt like a monstor untill it started hopping again when the sled bogged down.

The truck weight in at about 7200 most pulls with just some junk thrown in the bed, do I need to run with more weight?

should I hang weights off the front? Also, I'm going to put 4.10 axles in for this summer, what would be a good gear to run in? 1st HI or 3rd Low?
84 CCLB W350 project
94' W350 Dually, Diesel, Auto 1080HP/1980FTlbs
User avatar
ahale2772
14mm rotor
 
Posts: 2353
Joined: Tue Jul 21, 2009 9:43 am
Location: massachusetts

Re: Hopping

Postby KTA » Wed Mar 02, 2011 2:20 pm

Run as much front end weight as you can. Also tire pressure effects it as well.
Fleet of Junk: 1989 D350 627rwhp 1300 tq B-1/Hx60 twins, KTA pump/injectors, ported head, BIG fuel supply. 13.75@ 109.5mph 1/4: 1992 W350 Cab-chasis, 1993 W350 ext cab cust.370 inj Hx40/16cm 290rwhp hydroboost brakes,1984 D350 crew-cab another project.
User avatar
KTA
diesel guru/mod
 
Posts: 1855
Joined: Thu Jan 04, 2007 2:23 pm
Location: Shelby County, Ky

Re: Hopping

Postby ahale2772 » Thu Mar 03, 2011 10:39 am

so if i load the front with weight should I just try to run the run the hitch up as high as they will let me? (i think 22 inch max)
84 CCLB W350 project
94' W350 Dually, Diesel, Auto 1080HP/1980FTlbs
User avatar
ahale2772
14mm rotor
 
Posts: 2353
Joined: Tue Jul 21, 2009 9:43 am
Location: massachusetts
Top

Re: Hopping

Postby rockjeep73 » Thu Mar 03, 2011 12:26 pm

Hanging weights will most likely get rid of the hopping. It will also allow you to pull further, putting more weight and traction to the front wheels, as long as your class allows it. Max hitch height should be 26", the closer you are to that the better, most of the time.
2000 QCLB 2500 4x4, 12.05 @ 111

89 D-250, In The Graveyard

89 W-250, Mostly Stock

http://www.SHSDiesel.com
rockjeep73
fuel screw!!!!
 
Posts: 114
Joined: Sun Dec 16, 2007 10:43 am
Location: Folsom, CA
Top

Re: Hopping

Postby MMiller » Sat Apr 23, 2011 8:02 pm

I would highly recommend not using high side of the transfer case. It will increase the chances of broken driveline, between the trans and transfer case. Use low side of the t-case, and if you have a good enough clutch you should be able to pull 3rd gear.

A fellow truck puller once advised to me when my truck was bouncing, "A flat basketball can't bounce." I run pretty low air pressure in my front tires, but its likley you can run much more front wieght then I do. The more power you have and the higher you run the hitch, the more you will fight bouncing, but with patience and practice, it will work.

Michael
1993 W250, 3.55, NV5600 , Con O, bosch 185's, 4" exhaust, Super 40, pump tweaks, ground pin, Smokehouse air intake, Hamilton Cam,
1985 D350, Crew Cab, 92 cummins and a 518. 47rh to be built and installed along with 3.55 LS Dana 80
MMiller
fuel screw!!!!
 
Posts: 391
Joined: Mon Jan 08, 2007 6:26 am
Location: Lenox Ia
Top

Re: Hopping

Postby slingshot » Sun Apr 24, 2011 4:36 pm

Got any pictures of your traction bar set up?
1993 W250 5speed.
User avatar
slingshot
fuel screw!!!!
 
Posts: 102
Joined: Sun Oct 19, 2008 8:43 am
Location: Oklahoma
Top

Re: Hopping

Postby ahale2772 » Mon Apr 25, 2011 2:47 am

me? ive got some somewhere... (a couple crappy pics)

viewtopic.php?f=10&t=8724&p=62884&hilit=goodies#p62884

the front mount for the bars is right behind the yoke coming out of the 205, Pullit advised me to not mount them on the highside either.

I was running my 33's at 30lbs when I pulled but I think you are right, I could have gone less, overall I think I was too light.

the last run I ran the hitch up 2inches and it made the truck Hook hard when I was nice to it/ fed the power in nice but when I mashed it it would spin then grab and send the truck into a hop
84 CCLB W350 project
94' W350 Dually, Diesel, Auto 1080HP/1980FTlbs
User avatar
ahale2772
14mm rotor
 
Posts: 2353
Joined: Tue Jul 21, 2009 9:43 am
Location: massachusetts
Top


Return to Competition

Who is online

Users browsing this forum: No registered users and 15 guests