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borch82racing
07-20-2010, 09:47 AM
I have a WISSOTA Midwest Mod that is a 4-Z that is very tight on entry until about the middle of the corner then it breaks free and has a good drive off the corner I just can't enter the corner. It doesn't seem to matter if I am on the gas or not on the gas it still pushes my j-bar is almost as high as it goes on the frame and on the pinon side I could go up one more hole. Right now I am running 75 lbs. of bite my front springs are: LF: 800 RF: 700 rear springs: LR: 175 RR: 200 I have changed rear springs the amount of bite moved the j-bar and nothing seems to change the problem. The car does drive good when the track is greasy for hot laps but as it dries out and gets tacky it goes right back to the push. Looking for some suggestions on what to try next to hopefully correct this problem any help would be appriciated.

Also I am having a problem with my power steering I don't notice the problem on the track but when I unload the car at home sometimes I can barely turn the wheel but yet sometimes it is ok I have the 605 steering box and a KRC power steering pump, but I don't know if it is a problem with the box or the pump. I have noticed that after I finish a race that the steering box is very hot. Any ideas on this also would be appriciated!
Thanks
DB

washeduptoo
07-20-2010, 10:16 AM
How much rake in jbar? What are your bar angles in degrees, the rr forward bar should be uphill to the chassis 5-10 degrees and the rr rear ward should be down hill on chassis about the same, you can move the forward up to loosen more or move the rearward down on chassis. How much trail in rr? Is your pull bar centered on rear end and at the front? Swap the rear springs around would help some. What off set wheels are you running? Where are your springs located on rr and lr? Just some things to think about and is the rearend left to right where it should be? Good luck. Have you tried less rear percent?

wicked1
07-21-2010, 02:05 AM
more than likely you are feeling the torque converter is why it is tight on entry...other mods don't have to deal with this...when you hit the corner the converter and all its oil still has all the momentum, which is causing you to be tight in....check your rearend for square, lead, or trail.... if it is lead than square it, if it is square than trail it... wouldn't go over a .25 inch at a time

hpontap
07-21-2010, 07:21 AM
The one thing that stands out to me is the rear springs. LR 175 RR 200.
I would swap them. Getting more weight on the LR should free the entry off the throttle.
You did not mention brake bias either. When tacky I always crank in rear brakes to help turn then turn in more front when it slicks off.
Wheels offsets help also. Suck the RF in or LF out or LR in and RR out. to free the car up.
All this is assuming that bar angles , J-bar angle etc are close.
Are you trail braking the car going in?
The power steerring pump is probably weak if the gear is hot.
Good luck

cjer
07-21-2010, 07:48 AM
Can anyone do a good "J-Bars For Dummys"? Like Angle + would = ?, Angle - would = ?, Mount at pinion higher would equal ?, Mount at chassis higher would equal ?.
Would be helpful to me.

JustAddDirt
07-21-2010, 09:57 AM
Put a straight panhard bar on it. I had same problem, and changed to a straight bar, and won right out of the box with it.

sobe92
07-21-2010, 11:10 AM
Jbars for dummies... the shape of the bar itself has no effect other than clearance. What does matter is the overall center to center length and the distance from the ground to each mounting point. About 5 inches difference is a good place to start. Higher on the frame side. Assuming it hooks to the chassis on the drivers side of the car. Center of pinion is a good place to start. Move it down on pinion for more sidebite and up for less. Raise it up 1/2 inch at a time on frame for more side bite and down for less. Longer j bars react slower than short ones. Short left side of pinion mounted bars are erratic they are good on stop and go tracks.

The reason the short straight bar worked was it drops as you decell and your sidebite goes away then comes back as you pick the throttle up.

JustAddDirt
07-21-2010, 01:16 PM
The reason the short straight bar worked was it drops as you decell and your sidebite goes away then comes back as you pick the throttle up.[/QUOTE]

I never completely let out of fuel, so the car never comes down. But the J bar had the RR tire planted too much. So you are correct above to some extent. I just transfeered the load to the left side of pinion, instead of the right. My J bar was 20"long. my straight bar is 17" Just moved the loading point on the rear end, which has taken some of the pressure off the RR on entry to loosen it up a bit.
Might be a thing to try for the gentleman above.

washeduptoo
07-21-2010, 02:22 PM
Justadddirt, are you running the bar underneath the pinion or on the left side with a different type frame mount? Thanks, would like to try a short straight bar to the left side of pinion again with the 4-4 floated set up.

JustAddDirt
07-21-2010, 04:15 PM
Justadddirt, are you running the bar underneath the pinion or on the left side with a different type frame mount? Thanks, would like to try a short straight bar to the left side of pinion again with the 4-4 floated set up.

I am on the left side of rear end now, but I have the one hole under the pinion I am going to try.
On the frame I have the 3 hole mount. left, center, and right.
I am in the left mount of chassis for the straight bar to the left side
To go to the center under pinion I am going to have to go to the center or right mount on chassis, as well as move it down on frame.

erm11
07-21-2010, 04:38 PM
How Much Angle In That Straight Bar Joey?

washeduptoo
07-21-2010, 04:57 PM
I think if you can get the right length straight bar and the right rake, you could have more forward drive as the it would push down on the left side as it lifts. Of course you would be giving up some side bite and would have to adjust for that. We ran that for one race a couple of years ago on a slick stop and go track and it worked fine, haven't tried it since. Thanks for the help and our bar was about 9-10inches(I think).

KeimRacing
07-21-2010, 05:14 PM
I will take a stab at it...I can't believe nobody has mentioned it.

Soften your Left Front Spring.

I would go to at least a 650. This will loosen the car up on entry, and should be a big enough change to notice if it helped the car turn or not.

Mod77L
07-22-2010, 12:58 AM
Here's a shot in the dark...

If you are not getting a lot of RR shock movement, I would check the RR eliminator for bind.

When you mentioned the heavy track, I remembered a time when my RR eliminator needed a rebuild.

It was fine when moved straight up-and-down, but as soon as any side load was added, it would stick.

It wouldn't allow the car to roll over on the RR, and thus was great in the heavy clay, but as soon as it dried out, it was as tight as could be.

Either replace or rebuild the eliminator, or move your shock ahead of the axle and add a coil-over kit (for the 5" spring).

That is, if I hit my mark, lol... :p

junebug
07-22-2010, 02:04 AM
Do u have a lot of angle in ur right side bars that might be wats holding the car off the rr too and another thing I noticed is u can only go up one hole on pinion side try dropping the jbar down you've got ur rear roll centers pretty high it sounds like

JustAddDirt
07-22-2010, 09:24 AM
How Much Angle In That Straight Bar Joey?

3" difference in heights.