Mod diary for the streetpirate XJ

[tealcherokee]

Re: teaser

heres mine, 255/55-16 on 16x8's with 5" of backspacing they stick out about 1.5" more that the stock one, right at the edge of the flares

 

[A Satria]

Front AMG Wheel 7.5 inch x 18, Tires 255x50x18
Front AMG Wheel 8.5 inch x 18, Tires 275x55x18

Center Cap is still Mercedez Benz, I'll Replace with JEEP Logo

 

[Beej]

Front AMG Wheel 7.5 inch x 18, Tires 255x50x18
Front AMG Wheel 8.5 inch x 18, Tires 275x55x18

Center Cap is still Mercedez Benz, I'll Replace with JEEP Logo

Interesting tire and wheel combo, 255's are 28" tall, 275's are about 30" tall. Did you replace one set of gears to make up for the difference in tire sizes from front to rear?

 

[streetpirate]

what did i tell ya, theyd stick out about 4"

looks like a mexican low rider

Damn.

well, looks like ill just have to start shopping for dingleballs and paint it purple

 

[A Satria]

Interesting tire and wheel combo, 255's are 28" tall, 275's are about 30" tall. Did you replace one set of gears to make up for the difference in tire sizes from front to rear?

Sorry for the WRONG info

Tires are 255x55x18 (Front 7.5, Rear 8.5 inch AMG Wheels)

 

[tealcherokee]

VERY nice looking jeep.....glad to read you wrote the tire sizes wrong

 

[A Satria]

XJ Street Persuit

VERY nice looking jeep.....glad to read you wrote the tire sizes wrong

Thanks, But you guys have a Better Performance ENGINE,... its so very hard to get such parts right here,...

Anyway, no matter how much HP you have under the hood, THIS IS the FASTEST way to go thru traffic (Code-3 Undercover Strobe Light, Wheelen Dome Strobe Light, Code-3 Siren):shocked:

 

[mingo]

Tires are 255x55x18 (Front 7.5, Rear 8.5 inch AMG Wheels)

Do your tires rub the fenderwells ? No problems with the fit? Looks good. Thanks for sharing.

 

[A Satria]

Do your tires rub the fenderwells ? No problems with the fit? Looks good. Thanks for sharing.

Thank you, you are welcome.
Not at all.

ActuallyaAt rear, it will be lowered 1.5-2inch, and Front will be lowered 2.5-3inch.
Hopefully it will ride on COIL-OVER Shocks at all corner and of course a "STIFFER Coil Spring"

 

[tealcherokee]

just so you know, if you want suspension travel, you cant drop it more than about 1.5", anylower and your front axle will become one w/ the oil pan. Im dropped about 1.75" and its getting real close with 1" of travel b4 i hit my bumpstops

 

[A Satria]

just so you know, if you want suspension travel, you cant drop it more than about 1.5", anylower and your front axle will become one w/ the oil pan. Im dropped about 1.75" and its getting real close with 1" of travel b4 i hit my bumpstops

Good Point !!! :explosion
My Wrangler YJ has 18" of front travel and 24" of rear travel.
But, it is a custom built YZ (chasiss lenghten, Engine moved almost inside the cabin, etc), and I never had XJ before. Actually I have this XJ just almost 2 months..., my thought that it would be so easy and simple to DROP the Ride-Height.

You made your point, actually I was just under the cherokee for a while and see what you mean....

Thanks,...

 

[tealcherokee]

not a problem, i was hoping for the same thing actually, but, its not gunna happen

 

[xuv-this]

How do you figure 400hp at the wheels or even the crank. On dyno2000 it takes at least 15psi of boost to make 400hp on a 4.0L. The block can't take that, factory pistons and rods definately can't. You can't run lots of boost with a radical cam, and the parts to make such an engine would put the cost through the roof. It would cost so much that it would be just as feasible to drop in an srt10. A blown stroker wont get you to 400hp (crank) with any reliability. There is a lot of imaginary engine building without any thinking going on in this thread. Don't get me wrong I own a built stroker in my wheeler and my dd is built for the street and has a built 4.0L but you have to be realistic when you talk about stuff. I'm all for throwing engine ideas out there and being creative but at least think about things long enough to realize it is impossible to make near that much power with the 4.0L.

im kinda drunk right now but i yes have figured that up in my head. i willexplain but correct me if you think im wrong. most of blower kits have dyno specs for wrangler 4.0s. the xj makes about 10hp more because of exhaust differences i have seen in a couple of places and saw a dyno sheet for a avenger i think and the xj made about 310 on street boost stock motor. all the basic power upgrades on stock are = 45 hp and 310plus 45 is about 350, not including the extra 10hp at least you would get from the bllowers increased air delivery from the motors mods. up the boost a little bit, add the hesco head and yeah i would have to make an " unedumicated guesstimation" of the neighborhood of 400 hp prolly not more than that very relaibally but reeallly close .

the stock 97 i think up pistons and rods are stronger than the older stuiff too. my only concern with the stroker is that it would take longer to spool up and not harmonically balence as well. the theoretical top speed of the xj 4.0 well exceds aerodynamics and governer so drop the gears and make more use of that power.:repair: whaddya think? :bunny:

 

[tealcherokee]

How do you figure 400hp at the wheels or even the crank. On dyno2000 it takes at least 15psi of boost to make 400hp on a 4.0L. The block can't take that, factory pistons and rods definately can't. You can't run lots of boost with a radical cam, and the parts to make such an engine would put the cost through the roof. It would cost so much that it would be just as feasible to drop in an srt10. A blown stroker wont get you to 400hp (crank) with any reliability. There is a lot of imaginary engine building without any thinking going on in this thread. Don't get me wrong I own a built stroker in my wheeler and my dd is built for the street and has a built 4.0L but you have to be realistic when you talk about stuff. I'm all for throwing engine ideas out there and being creative but at least think about things long enough to realize it is impossible to make near that much power with the 4.0L.

im not going to have an issue hitting 400hp at the crank w/ 6psi from a turbo....why should a blower be any different

might even get close to 400 WHP when i put the intercooler in

im putting down about 240 with just the stroker to the wheels, figure another 120-130 from the turbo thats 360 on the low end, 20% drivetrain loss thats 432 at the crank

 

[A Satria]

im putting down about 240 with just the stroker to the wheels, figure another 120-130 from the turbo thats 360 on the low end, 20% drivetrain loss thats 432 at the crank

Would you share how you get 240 WHP ?
How is it stroked ?, and what other perf parts are installed ?

 

[tealcherokee]

4.5L, moved piston pin offset, 9.8:1 compression
open header, cold air intake
ported head

its a calculated 240, so i said about, i can guarentee is no lower than 235

im taking it to the dyno hopefully next week

 

[A Satria]

4.5L, moved piston pin offset, 9.8:1 compression
open header, cold air intake
ported head

its a calculated 240, so i said about, i can guarentee is no lower than 235

im taking it to the dyno hopefully next week

Sorry that I've asked you these "STUPID" questions....

• 4.5L, > yes, mine is also 4.5 using different crank
• moved piston pin offset > Why ?
• 9.8:1 compression > seems mine is also around 9.8 cr
• open header, cold air intake > same here

My HP is alny 135 on rear wheel HP
I've tune it on DYNO, using programmable ecu, tuning for best A/F

What else do I have to do ? to do

ported head > Does that mean ported head alone would contribute so much HP ?

 

[tealcherokee]

135 wheel horse is less than stock..... with an auto 153 WHP is about average, bone stock high output

piston pin offset is a little builders trick. the pins come from the factory offset to reduce piston slap, but at TDC it puts the connecting rod at more of an angle, when the plug goes off, the increased angle uses more of the energy to push the piston sideways, before down, flipping the piston over, or moving the offset to the oppsite side, straightens the rod out, giving about 10% more power to making the crank go around (thats 25 horse on a 250hp motor!). the only draw back to this is piston slap, it soulds similar to a lifter tick, and it coud be damanaging to cast pistons, tho thats what im running for right now....

 

[A Satria]

135 wheel horse is less than stock..... with an auto 153 WHP is about average, bone stock high output

If your engine only has the 258 crank & rods but is otherwise internally stock (the 9.7:1 CR is the result of the longer stroke) and you have no performance mods, your HP/TQ numbers would make sense.

Tealcherokee,
So does my 135 Wheel HP seems right or wrong. Please re-confirm on this.

 

[Dr. Dyno]

Tealcherokee,
So does my 135 Wheel HP seems right or wrong. Please re-confirm on this.

You got 140hp/195lbft at the wheels and that's right because you got those figures on a 4WD dyno where you can expect a drivetrain loss of ~29% (4WD automatic). As I told you before, that equates to ~197hp/275lbft at the flywheel. Considering your engine was bone stock except for the 4.2 crank & rods and you had no external bolt-on performance mods, those numbers are in line with expectation.
Most stock automatic 4.0 XJs dyno at 150-155hp at the REAR wheels on a 2WD dyno, equating to 188-194hp at the flywheel (20% drivetrain loss for 2WD automatic) so now you know why the factory rated the engine at 190 flywheel hp.