• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Stage rally truck prep - need opinions

sureshot007

sureshot007

NAXJA Forum User
Location
Kenmore, NY
I posted this over on comancheclub, but thought I'd see what people have to say here about it:

So I ran my first stage rally this past weekend (STPR). It was a learning experience. The comanche is a stock 86 2.5L rwd with a 7' bed. We need to do something about power and suspension. Since this is my first comanche, I am looking to you guys for guidance on the best bang for the buck stuff, as racing gets expensive quickly.

First, let me introduce you to "The Chief"

IMG_8860.JPG
IMG_9341.JPG

IMG_4052.jpg
TheChief.jpg


http://www.youtube.com/watch?v=LGodutFAalQ (we are at about 7:00 into the vid)

What I am looking for is a suspension setup that would work like a baja trophy truck, but made from as many off the shelf parts as possible. And the rear drums have to go. So we were thinking of swapping a cherokee rear end, maybe an air locker?, stiffer springs front and rear, and good shocks. And a 5 speed, because this 4 speed is brutal on transits. We are also looking at options for the 2.5L for more power. Plus we need to chop the bed behind the wheels.

So if you were building an offroad race truck (think baja, not rock crawler), and you were on a tight budget, what would you do?
 
Id find a 44 rear end or something stronger, truss the rear and the front I beam, gussets on everything that could ever need it: ie knuckles controll arm brackets, leaf spring mounts gear box etc... id spend the money on a full set of hydro bump stops, Id lift it a few inches just to get more suspension travel, Id beef up the suspension with some stiff suspension, deffentally have a good cage (i dunno if you already have one since you already raced), id stroke a 4.0l HO engin and swap it in and call it done.
 
NICE!! that looks like a lot of FUN

1st Head to the junk yard

- Get a newer style Brake Booster/master cylinder assembly (double diaphragm)
- I guess it doesnt have a rear sway bar ( mine didnt) install one you ll attack corner 25 % faster
- a 4.0 6 cyl/ 5spd manual (Ax15 not the one you have) & I bet it will get scary

As
for suspension try to keep a low COG ( center of gravity) with stiff setup ( assuming its not your DD)

I d get a set of good expensive shocks anything larger than 2" diameter
try FOA & of course FOX or Kings or even Bilstein try to find a stiff valving (225+)

As for coils you can go for the coilover setup but since you want off the shelf; I think a heavy duty OME springs will do just fine

As for bump stops a good set of hydraulics (modification required) will definitely help try FOA or an ACOS, or if you are on a tight budget try these
& these

The list can go on forever depends on how much are you planning to invest
 
I guess I failed to mention in the first post that the displacement can't exceed 3 liters to stay in class - no 4 liter swap :(

Super stiff sways and springs are not great for gravel rally. Stiffer is good, but not track stiff. A super stiff shock on softer springs works better. Also, I don't really want to raise it much, since I don't need it to roll over. It has plenty of ground clearance as it is.

Keep the suggestions coming - they are really helping!
 
Lighter wheels will help acceleration and braking. Decrease rotating mass.
Any weight that can be removed? I'm sure there is something.
Can battery be moved to improve weight bias? Low in rear.
Can offset ball joints be used to get some neg. camber?
Rear suspension may work better with on less leaf. Your G.V.W.R. no longer applies.
 
have you looked at swapin in a latemodel 4poper in it ? i belive that they got a bump in hp and tq .

have you tought of dichin the bed and runnig fiberglass bedsides ,and linking the rear ?
 
deck the block, shoot for about 10:1 compression, give the head a good port job, open up the intake and throttle body as much as possible, a good header with a decent pipe, an adjustable cam sprocket will help move the power range up in the RPMs (if one is even available), stiffer valve springs, a good ignition system like MSD, an adjustable fuel pressure regulator and a good exhaust temp gauge will let you tune it well. A lighter flywheel will help the engine rev but you will sacrifice torque via rotating mass, so unless you plan to compensate by gearing that could be more detrimental than helpful. If cams are available then go for a higher RPM version, something with decent lift and good lobe seperation to help move the power band up. The only way to make good pow1er for what you are after is by revving the holy crap out of it. Good luck
 
sureshot007 said:
Super stiff sways and springs are not great for gravel rally. Stiffer is good, but not track stiff. A super stiff shock on softer springs works better. Also, I don't really want to raise it much, since I don't need it to roll over. It has plenty of ground clearance as it is.

Keep the suggestions coming - they are really helping!
Click to expand...

The stock rear sway bar is not stiff at all I drive mine stock with sway bars in the desert all the time, will help powering into a corner & allowing the rear to do its job ( more predictable oversteer)
 
You must log in or register to reply here.

Similar threads

I
Bought Son 2000 XJ, Need Help with RC Lift
2 3
Replies
45
Views
6K
Tim_MN
Tim_MN
macgyvr
***Trail communications - Radios***
Replies
2
Views
185
macgyvr
macgyvr
M
March Membership Drive 2024
Replies
4
Views
356
Rob Mayercik
R
W
Newbie with an XJ
Replies
8
Views
176
RCP Phx
R
REWSTER
Trail leaders wanted!
Replies
8
Views
856
chuck619120
C
Back
Top