PDA

View Full Version : tight on entry



washeduptoo
04-16-2014, 06:46 AM
Last week we went to a different track and with a different driver. Car was tight on entry and tight in the middle on the throttle. Going back to same track this week with the regular driver, going to change offset on rr from a 4 to a 3, hate to change much do to different driver. Front springs are 600 lf and 550rf and still have about 1in of shock rod left showing. Thanks

Dirtrunner35
04-16-2014, 07:12 AM
track real tacky ?

JustAddDirt
04-16-2014, 07:56 AM
raise j bar on rear end. that will loosen entry and middle

powerslide
04-16-2014, 08:21 AM
What else if the J-bar is already at the top on the pinion side?

HEAVY DUTY
04-16-2014, 08:35 AM
If the j bar is all the way up, there is probably something else going on. It isn't normal for the j bar to be that high, which is what would make me think it was something else. Make sure it isn't a brake problem first. The compression being too soft on the LR shock is the main thing that causes a 4 bar car to be too tight on entry. ( new driver not trail braking or arcing in the same as the other driver letting the LR drop on entry)

powerslide
04-16-2014, 11:00 AM
I was just throwing that out to see what i got for answers, i know nothing of the OP car or setup. Even w/ the quickchange you guys are never at the top on the pinion?

Racer96m
04-16-2014, 11:10 AM
I was just throwing that out to see what i got for answers, i know nothing of the OP car or setup. Even w/ the quickchange you guys are never at the top on the pinion?

Nope, never.

Dave

powerslide
04-16-2014, 11:41 AM
I started with mine at the top on my q/c. It was about a inch above the pinion i believe(i will double check) which is in the bottom hole or pretty close on a 9in. Car was still usually tight on entry on hammer down bull ring. What are you guys doing to free the car up to compensate for the low panhard location? How much trail? front spring split? You guys run UMP tires so that may play into the balancing act as well.

jsf74
04-16-2014, 12:13 PM
Dont lightning mods have the panhard bar mounted all the way up on the pinion mount?

z40chief
04-16-2014, 12:34 PM
Dont lightning mods have the panhard bar mounted all the way up on the pinion mount?

Heavy Duty should know since he builds Lightnings.

JustAddDirt
04-17-2014, 07:28 AM
jsf74

straight panhard bar mounts to top of pinion plate.
j bar is 1" above pinion centerline. Per Lightning set up sheet.

washeduptoo
04-17-2014, 08:49 AM
Sorry I haven't answered back sooner as I had a brother-in-law having surgery yesterday and when I got home, I couldn't get on 4m. We are at center of pinion on qc and if the offset doesn't work, that would be a good adjustment. Thanks for the help.

HEAVY DUTY
04-17-2014, 09:04 AM
Using the term" top" on the pinion plate differs with which pinion plate you have. Some are 3" above pinion, while others are 1" above pinion. It is common for a J bar to be between 1 1/2" above to slightly below on a mod. A straight bar on the left side of the pinion is usually higher than the J bar would be.

washeduptoo
04-17-2014, 09:38 AM
What about moving the lrt bar up past the 45degree angle to add more rear steer, lr is chained at 45 degrees right now. What about swapping front springs or putting a 600 in rf? What do y'all think of these adjustments? Thanks

Flyin Iowan
04-17-2014, 10:16 AM
What about more stagger?

JustAddDirt
04-17-2014, 10:55 AM
washeduptoo:
you will probably over-index top radius rod, more top bar angle is not the answer.
more lower bar angle could help,
either bar adjustment, driver would have to be on throttle for changes to take effect, since it is tight on entry, I am assuming they are off throttle some.

try 1" - 1.5" above pinion centerline.
or soften LF spring.
make it an easy quick adjustment.

washeduptoo
04-17-2014, 12:39 PM
We tried to increase stagger and all we can get with the tires we have now is 1in unless we blow it up and let it set ARkk704 tires. Not really wanting to do that at this time due to the usually driver will be in the car this week and the same track, things might be different but who knows. Thanks

JustAddDirt, moving the jbar up on pinion is something that we can look at if this continues as its an easy adjustment. Thanks

Another adjustment I thought about was shorten the lr drop by .25 but that will take away rear steer and maybe forward Thanks

I will have to ask the driver on the entry tight.

powerslide
04-17-2014, 02:39 PM
I would look at the LF spring. That was my next move if we had more races last season. My J-bar was already in the "top" about 1in above the pinion

washeduptoo
04-17-2014, 02:51 PM
Might have to do that next week since it would require getting another spring and scale. Got another 600 but not a 550. Was thinking of swapping the front springs to see how it does before buying another spring or putting the 600 in rf, might kill two birds with one stone, loosen entry and give drive off. Thanks

Dirtracer50
04-17-2014, 10:16 PM
Maybe try trailing the RR a small amount and see if that helps.

washeduptoo
04-18-2014, 01:32 AM
Thanks, might have to try that as we did just close that up. Thanks

washeduptoo
04-20-2014, 12:25 AM
I guess the 3in offset on rr worked for the regular driver, thanks for all the suggestions.