Hotrod Cherokee

[JJacobs]

I'd love to get some more info about this thing. As of right now no pics but will get some pics and hopefully info next time I see it in a few weeks.

It's a 97+ XJ that's running in the King Street class at Bandimere. I do know it has a 4.0 based engine and some type of centrifugal supercharger, a Vortech or Procharger maybe. It was running 12.4's at 113 or so, which for the rest of the country calcs out to 11.5/120ish. Jeep looks to be full weight.

Cool to see someone putting some real boost to a 4.0, anybody know the guy?

 

[bjoehandley]

Haven't seen or heard anything about that, but that sounds like it would make one hell os a street machine, and be interesting to see how that compares to the Boostwerks and Boostec XJ's too.

 

[JJacobs]

I've seen the Boostec XJ, and it would have nothing on this thing, no offense to anybody..

 

[eflores]

What's the matter Jon u getting the itch to go fast in a jeep again?

 

[JJacobs]

Nah. got the car for that. I do miss the ol' turd though.

 

[urban yan]

Don't be silly. Turds are more aerodynamic than our XJs

 

[eflores]

Ok we need mj pics or this thread is a fail Jacobs......

 

[JJacobs]

Nah, this is an XJ thread. Oh yeah.. it's purple.

 

[eflores]

This thread is bringing all the fail.

 

[JJacobs]

I'll see if the guy will let me take underhood pics next time I see it. Until then, yes it does bring the fail since nobody's heard of it.

 

[YELLAHEEP]

I just tried some extensive googling........ nuthin.

 

[JJacobs]

The XJ was at the track again today running 12.4's at 108, so around 11.2 for you non-altitude-impaired folks. It's running a stroker with the 12-counterweight crank. Custom pistons and rods, ported head, 12 psi off a Vortech V-2 something or other trim.

He says about every 6K street miles the motor has to be torn down to replace the cam bearings, first indication is a small drop in oil pressure. Supposedly at that power level the cam flexes enough to tear up the bearings. It's shifted at all of 4800 rpm.

He says the power is around 420/750 rwhp/tq. Can't quite get my head around the torque number. No pics, sorry.

 

[old_man]

Jon,
Unless the cam is running a ton of lift, why would the cam flex with more HP. I can see rpm's figuring into the equation, but at only 4800???? Is the blower causing it to be harder to open the valves?

 

[JJacobs]

Probably. The intake valves act as a parachute to the air flow with a lot of boost pressure in the plenum.

 

[YELLAHEEP]

Grrrr @ no pics.

Is the guy associated with any shop in town?

Can't believe this guy is into racing an XJ and isn't on any XJ related forum at all.....

 

[JJacobs]

Yeah, I know. Hard to keep up w/ everything when you run two classes. He was loaded and heading out before I even realized it was there today. The owner's been racing for a while, decided on something different and built it. Not much of an internet guy.

So it's not purple, it's dark blue. ZJ 4.0 auto trans, built. 2WD beam axle up front. 8.8. Used Vortech for 1500, fab some brackets. Brace to valve cover studs. Tuned with SCT on the stock ecu. The major pita part looked like the giant drive pulley bolted to the damper. I was quoted $700 to build a similar pulley a few years back.

So there's the recipe, who's up?

 

[gradon]

We'll see what direction my brother goes when he breaks in his stroker(still a month or two out), but he originally wanted to turbo it. I'd go twin screw, ala Sprintex or Avenger, over centrifugal(Vortech).

 

[BlueCuda]

Yeah I don't see cam flex bieng HP related and I am sure its not running valve springs strong enough to cause the issue. Something has to be wrong. With 7 cam bearings it seems there should be no problems?

Sounds like a fun ride, i would rather keep it 4wd and run it on street tires for a good sleeper look...its probably easier to drive in 2wd with a good tire though.

 

[JJacobs]

We'll see what direction my brother goes when he breaks in his stroker(still a month or two out), but he originally wanted to turbo it. I'd go twin screw, ala Sprintex or Avenger, over centrifugal(Vortech).

Either of those capable of building enough boost without a ton of heat? How's the intercooling options? I think the Roots style loses out without intercooling.

edit: looked at Avenger's site and they do show an intercooler. I don't know about the boost capacity of their system though. They say 5 psi and it's already got a fairly small pulley. So if the efficiency is there you could go up on the lower pulley and down on the top one but it's not set up to make the kind of power a decent size centrifugal will. It's a kit for stock motors.

 

[bjoehandley]

Either of those capable of building enough boost without a ton of heat? How's the intercooling options? I think the Roots style loses out without intercooling.edit: looked at Avenger's site and they do show an intercooler. I don't know about the boost capacity of their system though. They say 5 psi and it's already got a fairly small pulley. So if the efficiency is there you could go up on the lower pulley and down on the top one but it's not set up to make the kind of power a decent size centrifugal will. It's a kit for stock motors.

Depending On what fuel you run, you could run alcohal injection for intake charge cooling. Forhigher boost, I'd Run Byron's turbo set up.