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rob burgoon

Thunder Roadster handling

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rob burgoon

Hey guys, the way I have the springs set right now I'll occasionally see light or off throttle understeer in corners where I'm mostly coasting through. This understeer is nasty since lifting doesn't seem to help. I either need to slow more or boot the gas or shock the car somehow to get the car to start turning again.

 

However, I'll see oversteer at full throttle from 20mph to 100+mph. The rear just gets loose and stays loose and it's very much a "boot it and steer a lot" technique.

 

Is this normal with the locked rear end?

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Darrel

Rob, which body style are you running? I have the newer and have to battle tight the older style body are normally a little looser. The cars are always going to want to step out just a little at high speeds. Once you learn that they are very forgiving you just drive it that way. Junior Johnson always said "Lose is fast."

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rob burgoon

Old body for now.

 

Certainly loose is faster in these cars, but Darrel, if you think this is easy or forgiving, you need to try a miata sometime or hell, anything with a functioning diff. Power oversteer shouldn't be happening at top speed unless the rear is generating lots of lift or something.

 

Is your understeer stubborn to recover from? Have you driven a car that handles properly to have something to compare against?

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Darrel

Rob, I have driven some very good handling cars and own other race cars but would rather drive my roadster than anything else. If yours is that evil handling then something is wrong is your setup. Have you checked and made sure the rear end housing is square to the frame and not bent?

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rob burgoon
Rob, I have driven some very good handling cars and own other race cars but would rather drive my roadster than anything else. If yours is that evil handling then something is wrong is your setup. Have you checked and made sure the rear end housing is square to the frame and not bent?

 

It's not evil, more like "rowdy" and cars I'm approaching point me by out of fear more than anything else when they see me coming up since I'm not facing quite where I'm going.

 

"Mr. Toad's Wild Ride" is what it's like.

 

It's certainly a fun car to drive in that going fast actually looks fast with all the driver input, it just can't be making efficient use of the tires with that much oversteer or stubborn push depending on whether the power is on.

 

Would you describe your car's handling similarly?

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Darrel

No I wouldn't mine runs like it is on rails it only gets squirrelly when I over drive it or use the gas petal as an on -off switch.

BTW where are you located. We would love to have you run with in the SE. We have 10 Roadsters at Roebling this past weekend

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rob burgoon
No I wouldn't mine runs like it is on rails it only gets squirrelly when I over drive it or use the gas petal as an on -off switch.

BTW where are you located. We would love to have you run with in the SE. We have 10 Roadsters at Roebling this past weekend

 

San Diego. Have anyone in the SE that rents them?

 

A lap at WSIR with me behind the wheel.

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Darrel

Randy Suddreth and I have a Raodster we do arrive and drive with. PM me for detials

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rob burgoon
Randy Suddreth and I have a Raodster we do arrive and drive with. PM me for detials

 

I sent PM but never heard back. Did you get it?

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BigKeyserSoze

Make sure the corner weights are set right first, and that means with you in the car, alignment set, tire pressures set to hot, half tank of gas. Check and fix everything and get the crossweight set. Then check the front end alignment. I liked mine at around 2.0 on camber, 0 toe and as much caster as I could dial in. Then make sure the front and rear tires are square to each other. I played with the spring rates a bit, think I wound up with 275 front 225 rear on a newer body style.

 

This was the easiest of my cars to drive because of the locked rear end. They are almost impossible to spin because when the car gets crossed up, the back wheels drag to straighten the car. If you haven't corner weighted the car recently, you are just guessing at the problem.

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JAR19

Rob, if this doesn't mess your ride heights up too much, try taking out a round in both the LF and RF and then two rounds in the LR and RR. Tried a new setup this past weekend at CMP here in South Carolina and started off with the same issues you were talking about. Made these changes and it helped a ton, not only keeps the car stable but helped it to rotate center off and stay stable. Also check your toe should about about a 1/16 of an inch on these cars.

 

Here's a video from qualifying on board with me:

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