Lets say you were going to road race an XJ

[BlueCuda]

It'll take alot of effort to break a front tire loose on dry pavement with a 242 t-case and 225/70/r15 or 235/75/r15 all terrains and unless it's really, really slick, it's difficult to do on wet surfaces with balding but otherwise the same tires while accelerating hard! If you want more of a sway bar, why not look at the Addco bars, IIRC they're 1.28" for the front and 7.8" for the rear.

Remember its going to be leaned over running as hard as possible in a corner. Body roll and throttle could make it possible.

 

[bjoehandley]

Remember its going to be leaned over running as hard as possible in a corner. Body roll and throttle could make it possible.

Yea, I've done it with my '98 before.....usually in tight and/or off camber corners carrying way too more speed than most would think a XJ could carry into those kinds of corners. I'm just saying it will take quite a bit of effort to do so.

 

[Root Moose]

Breaking traction will not be a problem. Trivial in fact.

You guys need to go watch some newbie drivers in Subarus at an auto-x or similar. Lots of scrubbing, even with big, sticky race rubber.

AWD is no panacea. You have to tune around inherent understeer. Once you get that dialed in you are calling for lots of manhandling to be fast.

On dry pavement stick with 2wd. It'll be faster for less technical effort.

 

[IXNAYXJ]

Breaking traction will not be a problem. Trivial in fact.

You guys need to go watch some newbie drivers in Subarus at an auto-x or similar. Lots of scrubbing, even with big, sticky race rubber.

AWD is no panacea. You have to tune around inherent understeer. Once you get that dialed in you are calling for lots of manhandling to be fast.

On dry pavement stick with 2wd. It'll be faster for less technical effort.

Yup.

A 242 would be waaaay more complicated than any concievable gains you might get from AWD. We were only traction limited in two corners out of 15, over a 3 mile distance. And the only reason we really had issues in those spots was due to the tranny downshifting violently and breaking a tire loose.

With a tranny controller or an LSD, it would never be a problem. Any slight gains would be given up in weight and balance. On that note, I finally got around to weighing the Lemons XJ; 3200 lbs with me in it (I'm about 170), my laptop bag, an overnight bag and 3/4 of a tank, though with about a 400 bias on the front axle.

-----Matt-----

 

[IXNAYXJ]

Another thing to remember is these races are typically held on real race tracks; a "slow" corner is 45 mph. IF the front tires were to lose traction in an AWD set up, all you'd have is terminal understeer. You'd be forced to get out of the gas so you could steer the damn thing. Again, it's a solution to a problem that doesn't exist.

-----Matt-----

 

[Root Moose]

Ugh, you guys are running an AW4?

Is finding/swapping a 2wd AX15 a possibility? You need the control the manual gives for racing. The AW4 is no Porsche PDK.

What other transmissions could be utilized? I guess the later Jeep 6 speed has ratios that aren't biased right for road racing. Need to look it up I guess.

Isn't there a cheap way to swap a Mustang WC T-5 behind a 4.0? Spidey-sense says I saw that once upon a time when researching Javelins...

At any rate, the AX15 won't have great ratios for what you are doing but it'll be better than the 4 speed auto I'd think. Better practice your heel-n-toe if you aren't already doing it automatically.

3200 lbs... must be more to cut off?

 

[IXNAYXJ]

The AW4 was not my first choice, but given the alternative (BA-10), it was a far better option. Remember, we built this thing in 10 days for $350. Swapping a T-5 was not a viable alternative. Neither was an AX-15, for that matter. This is an endurance race; the most reliable option was the best one.

-----Matt-----

 

[Root Moose]

Fair enough!

Was thinking about the transmission today...

It might be interesting to take a look at the "Jeep" six speed... If the ratios from second through fifth are workable with a different differential gear and you could ignore first and sixth it might give you a close ratio option. I don't know the values, just throwing it out there as an idea.

Runwhatyabrung is a good option in budget racing.

 

[IslanderOffRoad]

Fair enough!

Was thinking about the transmission today...

It might be interesting to take a look at the "Jeep" six speed... If the ratios from second through fifth are workable with a different differential gear and you could ignore first and sixth it might give you a close ratio option. I don't know the values, just throwing it out there as an idea.

Runwhatyabrung is a good option in budget racing.

With what those cost it would probably blow the budget requirements for Lemons.

 

[Root Moose]

With what those cost it would probably blow the budget requirements for Lemons.

Depends... can see really pricey used parts go for a song when the person selling doesn't know what it is worth.

 

[seanyb505]

I thought it was be a good idea for my project - 6spd turbo stroker, but I seem to remember that the extra gear was a lower 1st and not just closer gears. I think some of the ratios may have even been the same

 

[RedChuck]

nsg370
4.46 2.61 1.72
1.25 1.00 0.84

ax-15
3.83, 2.33, 1.44, 1.00, 0.79

 

[Root Moose]

nsg370
4.46 2.61 1.72
1.25 1.00 0.84

ax-15
3.83, 2.33, 1.44, 1.00, 0.79

yeah, ignore first gear and treat it like a 5 speed with an appropriate axle ratio and it could be workable...


2.61 , 1.72 , 1.25 , 1.00 , 0.84