i am rebuilding a 4cyl in a 97 tj for a friend. last week he brought it to my shop with rattle and i pulled the pan to find the skirt had broke off #2 piston so he said fix it and make it better.im going to port+polish head,4.0 tb with spacer,header,elec.fan,4.56 gears. can someone point me in the right direction as to a good cam to use? is their a build thread on here that im not finding? i have built 6cyl strokers but i cant just throw a crank and rods in this one . my parts budget is about $1000.
here is my last build 4.5 stroker.
We all wish we could just throw in a crank and call it performance.
Well there is someone selling a mopar performance cam on here, might wanna check that out. Pair it with some high strength valve springs and lifters, plus a nice port and polish. Either that or Hesco now sells a full kit (I actually requested they make one, but didn't buy it...
).
That and all pistons, rings, connecting rods, custom or just aftermarket, will interchange between the 4.0 and 2.5. If a company doesn't have kits for the four cylinder you can probably just suggest they put one together for the growing market.
Heck, even many external brackets are interchangeable (note that I have a 4.0 vibration dampener on my 2.5, but the crank snout length is apparently longer on the 2.5, so a large washer had to be drilled/machined out in order to fit over the snout and allow the bolt to torque it down).
Somewhat unrelated to engine performance is a flywheel weight, bolts to the back of the flywheel (between it and engine I believe), smooths out vibrations, and allows the engine to really lug without dying.
If you get all forged and balanced internals the 2.5 will be really bulletproof and can wind up and breathe real well without encountering harmonic issues like the 4.0 does.
Look on the boards for more performance ideas. And as always, someone else chime in if my information is incorrect.
And do you mean the NVH girdle that can be found on later 4.0's? If so I didn't know that the 2.5 ever came with one...
