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mdadgar
10-03-2002, 16:23
So I took my truck out for a couple of laps at Thunderhill raceway yesterday (www.thunderhill.com) and the damned thing plows like a pig. I couldn't get the rear end to rotate through turn 11 no matter how hard I hamfisted the throttle.

Anybody got any ideas on how to improve this thing? Maybe some adjustable sway bars or something? Camber plates?

I mean, the Mustangs were dusting me, and we can't have that.

- Mark
'02 Sierra CC SWB 4x4 D/A

GMC D-Max
10-03-2002, 16:43
OK, I'll bite:

Rip all the 4x4 running gear out from under it, lower it about 12", then run stock car suspension (with monster springs in the front to support the substantial weight of the Duramax). Rip the entire interior out of it, leaving only a lawn chair for the driver's seat (to save weight). Rip the bed off to further lighten the load on the rear axle. Run open exhaust (the stock exhaust is heavy and only slows you down), add a BIG shot of nitrous, and carry only 8 gallons of fuel in the tank. Maybe then you'll be able to reel in those Mustangs! ;)

Oh, and cut the cab and frame off right behind the front doors, discard the rear doors, shorten the frame, and graft what's left of the very back of the cab onto the front, thus eliminating a TON of weight, and shortening the wheelbase substantially! Should turn-in nicely, now, and allow you to "hang-out" the back end!

[ 10-03-2002: Message edited by: GMC D-Max ]</p>

GMCTRUCK
10-03-2002, 17:00
Lower front air pressure a smidge and raise rear pressure. Trail break hard and down shift into the turn to unload the rear end. When you feel it loosen up stand on the go pedal. You'll go through the apex sideways and exit the turn like Joey Chitwood. I hope this helps your very serious dilema. ;)

bora
10-03-2002, 17:02
Mark

I don't know about turn 11, but I think you can use the uneven pavement on the inside of turn 14 to upset the rear end after which it rotates quite nicely.

In fact I go over some railroad tracks on my way from work every day and while turning if you hit the tracks, the truck rotates quite nicely indeed :)

mdadgar
10-03-2002, 17:14
GMCTruck, front tires are at 45psi cold and rears are at 80. Think that's enough differential? smile.gif

It really doesn't like Turn 2, either. Long sweepers just roll the front sidewalls over.

smile.gif

- Mark

imported_
10-03-2002, 19:09
niche bahn makes some really nice 24" wheels... 8-10" wide....put on some really nice nitto performance radials and then go kick sone butt!

GMCTRUCK
10-03-2002, 21:11
You could always convert the front to a dually. ;) :D

Professor
10-03-2002, 22:50
Run the inside wheels in the dirt. You'll spread enough on the track to slow down the Mustangs!

Colorado Kid
10-04-2002, 10:48
Now wiat a minute, back in autocross I used to LOWER the tire pressure in the end that I wanted to slide earlier...I think that 45 front and 80 rear may be a lot of your problem. I'd try about 60 front and 30 rear and it ought to be pretty sporty...won't roll the sidewalls over as bad either. Might also consider higher pressure in outside tires than inside tires...if all turns are the same way.

If that doesn't work disconnect the front (actually "only", as there isn't one in back) swaybar. It'll then roll to angles that'll make you green, but the rear will slide long before the front...probably with one rear tire off the ground!

battmain
10-04-2002, 12:08
You need more negative camber. Or you could do it rally style. Swing the steering the opposite way for the turn and then goose the throttle. You'll get some beautiful four wheel drifts. It's really the camber though. Turn your steering all the way to one side then step out and look how much positive camber you got. Compared to my stock race car, the truck steering has no feel whatsoever.

Brian

Corey S
10-04-2002, 14:41
:D :D :D

Mark, you're crackin' me up! The funniest part is that I've been there done that! Yes, this truck does plow on the track!

In addition to all those other suggestions above, don't forget the dubs with 335 wide rubber on 'em. smile.gif