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Old 09-05-2013, 04:41 PM
  #1966  
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Here's my car coming along.
Attached Thumbnails Ofna Ultra GTP2e-photo-4.jpg   Ofna Ultra GTP2e-photo-3.jpg  
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Old 09-06-2013, 08:11 PM
  #1967  
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GTP2 running 108mph & 105 mph on only 4s!

+ YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.
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Old 09-06-2013, 11:52 PM
  #1968  
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That's bad ass. 108 on 4s!
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Old 09-07-2013, 11:07 AM
  #1969  
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Originally Posted by DGRacer
That's bad ass. 108 on 4s!
Sure is bad azz!

Here's the same top-speed racer doing some body testing.

+ YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.


http://www.youtube.com/watch?v=zPmdGZA_EpM
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Old 09-07-2013, 11:16 AM
  #1970  
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That's freaking insane. I'm more than happy with 55-60mph tops on 4s.
What is your gearing for that sitting at? I'm at 20/46 thinking about bumping up a tooth or 2 just because. But i really dont need to.

I love being able to knock off a couple speed runs and then just parking lot bash'em and not feel the need to completely monitor temps etc.. I could certainly gear higher but i love just being able to plug and run for a pack.

i had mine out the other day in a soccer center parking lot and ran my 5200mah 4s down to 3.7v/cell on a relatively non stop bash session, brought it in and the Mamba Monster wasn't even running the fan at that point. I think they kick on at 160*f IIRC
I do want to add a motor fan though. Cant hurt to keep it down as well.
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Old 09-07-2013, 11:23 AM
  #1971  
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Originally Posted by Monteman
That's freaking insane. I'm more than happy with 55-60mph tops on 4s.
What is your gearing for that sitting at? I'm at 20/46 thinking about bumping up a tooth or 2 just because. But i really dont need to.

I love being able to knock off a couple speed runs and then just parking lot bash'em and not feel the need to completely monitor temps etc.. I could certainly gear higher but i love just being able to plug and run for a pack.

i had mine out the other day in a soccer center parking lot and ran my 5200mah 4s down to 3.7v/cell on a relatively non stop bash session, brought it in and the Mamba Monster wasn't even running the fan at that point. I think they kick on at 160*f IIRC
I do want to add a motor fan though. Cant hurt to keep it down as well.
Cameron,

He's run 146mph on 8s, he's impressive.
8 mph difference in just a lid, that's seriously cheap horsepower right there.
Take care!
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Old 09-07-2013, 11:28 AM
  #1972  
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Oh i know i have seen his vids. Crazy impressive.
I'm at this point definitely not all about the Aero.
After all I'm running a TRUCK on my GTP2e hahaha.

Kinda tough to kill some speed records driving a brick lol.
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Old 09-07-2013, 12:43 PM
  #1973  
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One thing i wanted to ask you all, maybe not so much the straightliners but the racers.
I get a TON of push (front understeer) right now with my set up.
Possibly just the tires i was using (Ofna Belted stockers)

But where should i be set up wise to be able to carve up some corners without hitting the blinker and dropping to 5 mph lol.

Toe/Camber F/R
I notice the front upper arms are adjustable front to back with spacers. Where should those be right now?
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Old 09-07-2013, 01:23 PM
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Story of my life summed up in a quick vine video...

https://t.co/DPM8PIuzZb
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Old 09-07-2013, 04:58 PM
  #1975  
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Originally Posted by Monteman
One thing i wanted to ask you all, maybe not so much the straightliners but the racers.

I get a TON of push (front understeer) right now with my set up.
Possibly just the tires i was using (Ofna Belted stockers)

But where should i be set up wise to be able to carve up some corners without hitting the blinker and dropping to 5 mph lol.

Toe/Camber F/R
I notice the front upper arms are adjustable front to back with spacers. Where should those be right now?
Cameron,

Chassis changes like: caster, camber, toe, roll center, oils, sway bars……… mostly affect steering at lower to midrange speeds and are all subjective to driver style, traction, track layout, power levels and tire wear patterns.

Driving with a “brick” body not only kills top-speed, but has a major effect on hi-speed steering & stability.

That’s why you always hear track racers saying…. “this body feels like it has more steering than…. fill in the ______” or “that body is too loose in the rear on exit” or “that body isn’t bad, it just doesn’t do anything right”.

If your car is “pushing” on the race track at higher speeds, the last thing you want to do is use a “brick” or a body that isn’t helping your car work better. Shelf queens are pretty to look at, but race cars need to actually work.

Once your GT car is going over about 20 mph, “mechanical” chassis grip starts to give way to “aero-grip”. "Aero-grip is what helps keep your car from "pushing" into the wall, board or pipe.

Want to test this theory????
Drive your car on a track for a few laps, then remove the rear spoiler and watch what happens to your driving lines, lol.

Aerodynamics is your car's very best friend.

Good luck and have fun!

Last edited by Jspeed; 09-07-2013 at 05:14 PM.
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Old 09-07-2013, 05:53 PM
  #1976  
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FWIW i had the heavy under-steer with the Corvette bodies too.
This is a setup issue im sure. Does it with the Sweeps as well.
Just looking for a setup sheet or something to compare to my setup.

I already changed the diffs around to the thicker diff up front and loose diff out back.
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Old 09-07-2013, 07:05 PM
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I have reset to stock as far as recommended settings. Hopefully it will help out some.
Not supposed to rain tomorrow so i should be able to get out and try this new setup.

Rear Camber -2*
Front Camber -1.5*
Rear Toe -1.5*
Front Toe +1.5*

Previous setup didn't have any toe out on the fronts. So i can only assume that wouldn't help much...

What about Caster? How should that be set? The manual really doesn't have a recommendation for that.
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Old 09-07-2013, 07:18 PM
  #1978  
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Originally Posted by Monteman
FWIW i had the heavy under-steer with the Corvette bodies too.
This is a setup issue im sure. Does it with the Sweeps as well.
Just looking for a setup sheet or something to compare to my setup.

I already changed the diffs around to the thicker diff up front and loose diff out back.
Cameron,

The Vette looks pretty, I used to race it on my IGT2 (long wheelbase) when Kyosho 1st offered it.

The Corvette had a nice amount of rear bite on turn exit, but pushed a bit on entry compared to the McLaren body; which was loose on exit because of its humungous roof line that partially blocks the rear wing.

I pretty much raced with all of the "replica" bodies; which was the reason I designed my own, for myself to have an advantage over the original Florida GT racer crew back in 2008.

What Tire brand name you use means little to nothing, because the wrong rubber shore or jacked up camber or droop will cause tons of problems. Too much toe-in or toe out can do weird stuff too. If the rubber is not matched to the temps, surface texture and race length, they will never perform at their best or last. (Unless you're one of the guys that doesn't mind changing after every qualifier or in the middle of mains)

What's the chassis set-up you're running now?
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Old 09-07-2013, 07:29 PM
  #1979  
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Originally Posted by Monteman
I have reset to stock as far as recommended settings. Hopefully it will help out some.
Not supposed to rain tomorrow so i should be able to get out and try this new setup.

Rear Camber -2*
Front Camber -1.5*
Rear Toe -1.5*
Front Toe +1.5*

Previous setup didn't have any toe out on the fronts. So i can only assume that wouldn't help much...

What about Caster? How should that be set? The manual really doesn't have a recommendation for that.
Ok, now we've something to work with.

Caster:

Less caster = harder entry on turn-in, more excited on input.
More caster = better turn exit, more relaxed on input.
The key is to find the balance between the two.

Front & rear camber:

You'll need to dial in by reading the tires.
Take a silver sharpie and draw a few lines straight across the tire surface; they run the car on the track. You don't have to go "balls to the wall", just fast enough to scuff the tires in a few laps. Then look at the tire, it will show you if it needs more or less camber every time.

Rear toe in:
-1.5 is kinda loose for track racing a GT car, maybe try -2 or even -2.5

Front toe out:
+1.5 is usually a good starting point, sometimes I've even tightened it up to +.5 and have had good results too.

What's your droop?
Springs?
Shock oils?
Diffs?
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Old 09-07-2013, 08:13 PM
  #1980  
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In the manual there is only provision for -0.5* and -1.5* rear toe.
This is changed by rotating the socket the hinge pin is held in with. Not sure how to achieve any more than that. Assuming aftermarket parts?

Not sure what my droop is at, but the droop screws are currently out the bottom about 1 full thread.
Running Red springs (From the DM1 i think, dont think these are the stock springs on the GTP2e)
35wt shock oil F/R
Not totally sure the diff oil either, much thicker up front (read that tight front loose rear is a bit "easier" to handle, the rear will just tend to follow instead of wanting to kick out)


Regarding Caster safe to assume "less" = all the spacers to the rear, pushing the a-arm to the front?
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