Engine Mod questions

I am new here, and this is my first post. I have an 87 Cherokee Pioneer 4.0 Renix, nothing done to it except a tornado, and a cat back straight pipe. It has the 3.07 gearing not sure which axles probably D35 rear D30 front.

I would like to know more about this stroke with the 258 Crank and Rods. If thats all I do to my engine is that really going to make it a 4.5 Liter? How much more torque is that going to give me?

I am also having trouble with the throttle body issue, could I just bore mine out, instead of taking one from a HO and making it fit?

Also I would like to know how to lower my gearing, I would like to get good gas mileage but also have good power, and belive me, my Jeep seems very weak sometimes, compared to Jeeps with lower gearing, and I only get 18 mpg anyway, I know people with lower gearing getting better. Any suggestions would be helpful Thank you.

Forget the engine just do lower gearing. 3.55 will seem better not too much difference in miloeage.. 3.93 or 4.11 will give you real seat of the pants difference if you leave everrything else the same. I have tried lots of bolt-on stuff (ram air tubes, etc..) not much difference. with Dana Axles its even do-able in your garage. NEVER MESS WITH A 8.25. Nothing is worth that headache.

Here's some stroker info. for you:

http://www.jeep4.0performance.4mg.com/stroker.html
http://www.angelfire.com/my/fan/stroker.html

the "tornado" doesnt do shit

redyouch said:

the "tornado" doesnt do shit

Click to expand...

Sure it does....










It helps empty your wallet with no performance gains.

18mpg would be concidered great milage for an xj.

i disagree. he didn't mention larger tires, so i'm going to assume it's relatively stock. my '88 4.0 with over 200k miles still gets over 18mpg with 33x12.50 tires.

I would expect to get over 20mpg with a healthy 87 with relatively stock drivetrain, I would consider 24mpg to be great.

I've got 235's on it. Where could I get new gearing for a Dana 35? I know that 4.88(thats low) is the lowest you could go from the factory, I think 3.73 or lower would be good, 4.11 would be nice, but how big of a fuel economy hit would I take if I had 4.11 gearing?

BrettM WHAT THE HELL DO YOU DO TO GET 20+ MPG????? My 87 has 208k on the clock(it's been towed behind a camper a lot) and I only get 18.

Haha my rear mounted tire carrier fell off, I was driving down town and boom it came off only connected by the steel cable connected to the bumper.(which is only connected by the passenger side mounting bracket) Luckily I was right next to Goodyear, they cut it off for no charge, I will remember that when I get my alighnment fixed, and oil changed. So it's all good now, my Jeep looks better without it anyway.

I need to fix my bumper and I need the brackets to do that. I figured I would get both brackets and fix it good because the one is under a lot of stress right now. From the dealership it's 58$ for both, from Quadratec it's 20$ for both. My question is do I need a credit or debit card to order from Quadratec, or will they take a good old fashioned check? If I must have it I will get a debit card because they got good stuff, but if they do take a check I won't bother with it.