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rajiex
2011.02.10, 08:04 PM
I had a problem with the my 94mm narrow Porsche 911 hooking to the left. Found on left turns that the right rear wheel would come off the ground. I tried different T-plates, shimming and finally settled that the problem was a tweaked chassis. Changed chassis to a new one, now the left rear wheels comes off the ground when i push down the right front tire.

I checked my other 94mm wide Corvette and found a similar issue. But all my 02s are planted solid. I am using a 94-98 PN MM mount in the 03 and 98-102 in the 02.

Someone said to try the SP 03 chassis. Is there something I am overlooking, motor wires are fine, rear is moving smoothly in both directions.

VAzRACER
2011.02.10, 08:28 PM
All my 03's do the same thing when I compress each side of the front suspension. In fact a few weeks ago another racer asked to see my car and checked the exact same thing, he tought his car was the only one.:rolleyes:

I use the sp chassis and its the same, I never looked into the issue because all the cars always drove fine. Now all I use is the tri-shock setup so I would never know if the chassis is tweaked since I'm basically zeroing ant tweak out with the side shock.

I know I'm not providing an answer but at least you know you not the only one. Like I said I never noticed anything odd on the track and the tweak was always fine when I checked it so I was never that concerned.

color01
2011.02.10, 08:56 PM
Tighten your screws very carefully on the 03 chassis -- it's a softer plastic, so when you tighten certain screws in the front end you can observe that the chassis actually flexes a little bit. :eek: For that reason I ended up investing in a new black chassis and a full M2 screw swap, the M2 screws providing finer control over screw tightening torque as well as holding on better in the hole.

herman
2011.02.10, 09:02 PM
haven't done any real racing to experience any tweaks... lol :D

if it's any help, kyosho made a cf underchassis plate... supposedly to stiffen the chassis... the part no escapes me at the moment... check this thread out (http://mini-zracer.com/forums/showthread.php?t=35451) at least he liked it...

wondering if anybody else was able to try it out... to give more input... hope this helps...

VAzRACER
2011.02.10, 09:21 PM
Tighten your screws very carefully on the 03 chassis -- it's a softer plastic, so when you tighten certain screws in the front end you can observe that the chassis actually flexes a little bit. :eek: For that reason I ended up investing in a new black chassis and a full M2 screw swap, the M2 screws providing finer control over screw tightening torque as well as holding on better in the hole.

I've noticed the same thing. Also one thing that always made me question the front end of the 03 was the plastic lower cover, everyone I have has a sleight warp. New or used there all the same but it has to cause the front geometry to be off a little bit.

lfisminiz
2011.02.10, 09:44 PM
I've noticed the same thing. Also one thing that always made me question the front end of the 03 was the plastic lower cover, everyone I have has a sleight warp. New or used there all the same but it has to cause the front geometry to be off a little bit.

Depending on the front you use (since theres so many variations), the PN parts will definitly help this situation.

VAzRACER
2011.02.10, 09:52 PM
Depending on the front you use (since theres so many variations), the PN parts will definitly help this situation.

Yea but I cant run the king pins I like with that setup.:p:rolleyes:

EMU
2011.02.11, 12:03 AM
Raj, what motormount/DDS system are you using with the Porsche? If it is the ATM, you have to make sure to mount the damper post to the forward screw hole or the damper plate will hit the damper arm. I shaved down my damper plate a little to clear the damper arm. If you are using the PN, please disregard this part of the post.

About the rear left tire lifting, and not the right, that is primarily due to the weight of the spur side of the diff being on the right, which is why the right side does not lift, but the left does.

I am sure that there is some warp in the plastic on the front end, especially depending how the screws are tightened (I always tighten the screws in two stages, one to get them in and the piece in place, the second time to tighten fully). I havent noticed it to be a problem, but I will definitely keep an eye out for it.

rajiex
2011.02.11, 04:57 AM
Emu,

I am using the Atomic steel plate and a top shock. I put the top shock plate below the DPS plate and I have no rubbing problems. RR front end with white springs.

On the first left off the long straight at Action, I roll the car on left turns. Tires are fine and centered. I can take a right turn at almost full throttle without a problem. Rob and Tom looked at my car, the only thing they could see was the rear tire lifting causing the hooking. I am wondering is the 911 body too high in the front?

EMU
2011.02.11, 04:42 PM
I lowered the front of Anthony's 911 GT3R... it does sit a little high, and this helped prevent the rear tire from rubbing the body.

rajiex
2011.02.12, 11:47 AM
I found out what caused the tweak..tore down the entire car..took care in reinserting the screws.. experimented with different shim thickness to get rid of tweak.. finally found out the top shock was the cause.. couldn't feel any binding in it but once i removed it, the tweak went away removed shims..no problem.. my home track is super smooth and very grippy because its new.. but not sure how it will handle at action.. does anyone rebuild the shock with a new shaft?