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rubbinsracin
06-24-2013, 02:45 PM
so we had a few weeks off because of weather and now that we are back at it the car was as i put it "stupid loose" from the middle off. We were in all of the standard holes in the heat and decided the car needed tighting up for the feature but we apparently we didnt do near enough.

here is what i changed from heat to feature

put on a higher rebound RF shock, lowered by right side bars on the frame, raised the Left Upper bar on the frame and put about 75ish more lbs of wedge in the car.

entry was fine but from the middle off was a challange to keep it straight to say the least.

What other things could i do to help tighten the car from center off on a nice smooth semi slick track?

JustAddDirt
06-24-2013, 03:25 PM
wouldn't a higher rebound RF shock kill middle off traction?

grt74
06-24-2013, 03:31 PM
yes sir it would

billetbirdcage
06-24-2013, 03:42 PM
raised the Left Upper bar on the frame and put about 75ish more lbs of wedge in the car.

entry was fine but from the middle off was a challange to keep it straight to say the least.



What was your reason for doing that? Think about it, all you did was add rollsteer assuming it was getting to the travel limiter before you raised it.

Raising the LRU bar isn't going to tighten exit, unless the car wasn't getting to the limiter to start with or if traction has dropped out of the track so bad it wouldn't have gotten up with the heat race LRU angle.

common mis-conception: more LRU angle more drive, not the case by any means. I would assume when you made sure you wasn't spinning the tires off the corner the ass end still wanted to go towards the wall (which is loose rollsteer but feels like wheel spin to most people).

rubbinsracin
06-24-2013, 04:23 PM
JustAddDirt - I did that to make sure that entry stayed good, which it did. I think if I stayed with my standard shock it would have hurt entry.

Billet - I didnt think of it that way. We just looked at our tuning guide and did a few things that it recommended we do. I think going forward im going to try to put the bars back to normal locations, add some more wedge, and shorten my right side bars about 2 rounds. those sound like reasonable adjustments?

Also, we have 2 sets of holes for our left side bars. A short set and a set that is 2" longer. Would it help to go to the longer bars?

4bangerhotrod
06-24-2013, 07:06 PM
you need to lower your LRL bar. this will tighten the car up adding alittle instant traction as soon as you hit throttle and make it drive alot straighter from the center out adding traction because anytime the car is drove straighter it makes better traction. as far as raising the LRU bar as long as your in the std hole, when you raise the bar 1 hole it should add drive to the car but its not going to tighten the car up much if any at all according to your bar lengths as to exactly what it does. also you said the you decided the car needed tightened up for the feature, so it must not have been to loose from the way you said that. it shouldnt take much to tighten it up just for changing track conditions. you added rebound to the RF which you prob needed to help hold the car on the right side for side bite but you didnt say how much rebound you had and how much you added. you prob didnt need to change any RS bars, changing them bars are really a pretty major adjustment for us. i think you would've been fine to add alittle bit of rebound in the rf, add the wedge and dropped the LRL bar 1 hole.

grt74
06-24-2013, 08:20 PM
if your cars good a 1st,your not far off,in my opinion its a weight thing,
think about it this way,how does the weight transfer now and how do you want it to transfer in the feature to get more traction,shocks are a factor in this
if your off alot there are alot of other factors in there too
also complete setup info will help because we dont know what your doing now,so we might suggest and hurt you
pm me if you dont want to give out your info

rubbinsracin
06-25-2013, 11:25 AM
the car is an 08 shaw. springs are LF 500 RF 375 LR 225 and RR 225. Shocks were a set built for the car and are afco twin tubes with a LRF shock that is a 6-0 gas afco shock. all bars were in neutral positions. limiter is set at 13.25" of drop. We started with about 40lbs of wedge and put about 75lbs (we havent scaled yet to confirm exact numbers but it should be close)

left side is around 52.7% and Rear is around 52% (we are going to hang some lead to get closer to 54ish% for next week) We have just been trying to keep as close to the minimum weight of 2250 but have decided that we would rather be closer to 2350 and have the right setup than to be at minimum weight.

Egoracing
06-25-2013, 01:52 PM
I think I would have dropped the LR bottom bar on the chassis, added 50lbs to the LF spring and MABEY raised the ballast in the car but that would have been about it.

rubbinsracin
06-27-2013, 09:00 AM
we think we figured it out. right rear shock lost its oil (guess a rod guide went) so i was just out here running around on the spring pulled the shock cover off and realized it at that point. thanks for all the input.

Matt49
06-28-2013, 03:01 PM
Very often when someone complains about a loose car on exit they really have a car that is way too tight on entry which can feel very comforting on a slick track and is often overlooked by the driver. They have to pinch the car in the center and slide it to get it to turn and then there is NO forward bite because all of the available traction has already been used up.
On a slick track your car needs to rotate freely getting in, generate excellent side bite in the middle, and then you will have all the forward traction you need coming off.
Food for thought.

rubbinsracin
06-28-2013, 04:23 PM
thanks for the input. we have thought about freeing entry just a little and will consider this. The car was easy to drive until last week, which was when we found the bad shock. hopefully that makes the car driveable from there.

Team_ASR
07-02-2013, 04:24 PM
I had a very similiar problem except mine was the exact opposite, I was too tight from the middle off. Try this adjustment and let me know what you think. adjust your J-bar; go up on your frame side, go up an inch and see what that does for you. all i ever have to adjust at the track in my J-bar to tighten or loosen the car from middle off, if it's tight/loose on entry then move the bars.

Ace