|Topic Review (Newest First)|
|03-28-2020 08:13 AM|
When I find another CJ or Wrangler, it's gonna have the 4-150 in it. My first Jeep had a carbureted 150, and it taught me a lot, at safe speeds
My 4.7 WJ is a lot of fun, making more power than I've had in a street vehicle -- including my old '76 CJ5 with the built 304, and that thing could out-drag race a '78 Z28 Camaro. But, for offroad, I think I'd like another 4-150 with correct diff gears. The only thing I'll change is go to fuel injection.
|03-23-2020 05:50 PM|
|80cj||As far as stroking the 2.5, I remember that in the 80's Mitsubishi developed a 2.5 or 2.6L four cylinder that performed quite well but in order to get the engine to run smoothly, they developed the counter rotating weighted balance shaft that ran off the timing chain. Four cylinder engines much over 2.6L would develop vibration which was referred to as "vertical shake". Chevy Novas had a 151 (2.6L) four cylinder that had a reputation for vibration.|
|07-06-2012 09:16 AM|
|reaxion911||I hear about boring out the intake but mine was the same opening size as the 4.0 tb it looks like it was meant to be. Run great and way better throttle response a little more power.|
|07-06-2012 09:10 AM|
Originally Posted by Trenton
|05-31-2012 08:51 PM|
throttle body modification
The 4.0l throttle body install on the 2.5L does make a very noticable increase in performance. The sensors all have to be used from the 2.5L throttle body including the IAC base housing that attached directly to the throttle body. The seat bore for the IAC in the housing for the 4.0L is larger than that of the 2.5L. If the housing is not change, the IAC will not have the ability to control the idle speed. This will allow the engine to run about wide open at idle. Also, prior to installing the 4.0L throttle body to the 2.5L the intake should be bored out to match the diameter of the throttle body. without doing this, there is not much need in making the swap!
|03-09-2012 12:27 AM|
just a thought
I was talking some things over with the guys at Jeeps R Us in Laguna Beach, CA and 505 Performance. it is possible to combine the 2.9 stroker with either a turbo from 505 or even the 2.5 supercharger from Avenger Superchargers. with other upgrades such as my new roller rockers (yella terra) MBRP exhaust, pacesetter headers, DUI firepower ignition, 4.88's, electric fan and more the 4 banger has the potential of 275+ hp with around 300 ft. lbs.
of course for 10000 is it worth it?...idk but i would like telling folks i have a 4 banger and being able to smoke some the rice rockets thanks to my fiberglass front end and trunk.
|07-23-2011 10:57 PM|
|Trenton||Thanks, im glad someone agrees that the 2.5 isnt a dog. does anyone know if a super chip flashpaq will work on a 2.5? when i search it, some sites say 98-04 gas dodges and some say 98-04 dakotas 3.9,4.7,5.2,5.9 but no 2.5. if they fit all those other engines they cant be designed for one specific vehicle so i dont see why it wouldnt work and since chrysler/dodge/jeep are all sorta the same it would probaly help other 2.5 owners. also the superchip part numbers will bring up dodge sometimes on one site, then jeep on another site? does superchip just want u to think its programmed for one vehicle or are they sorta universal between dodges/jeep between 98 and 04? thanks.|
|07-12-2011 07:37 AM|
|wendell||The 2.5 really isn't a dog, people feel they need race car performance from a jeep. Jeep are meant for off road. A 2.5 jeep will go anywhere off road that any other jeep will. They will do the speed limit on the road. I've had a couple of 2.5 jeeps over the years and they were a blast to wheel around in. With the 2.5, you don't want to over tire it. Run 31X10.50's and change gears to 4:56, or 4:88 and there quit peppy. You want a little more zip, install an intake, 4.0 tb, spacer, rollor rockers, cam, header and an e-fan. This will make a 2.5 jeep fun to drive. People want to put 35" tires on there 2.5 powered jeeps and thats just wrong. 31's are enough tire for most trails and do fine. People tend to want to run more tire than they need just because it looks cool. At over 200.00$ a pop, I'm over what looks cool and more into what works best for the kind of wheeling I do. On my built 258 with 4:10 gears I still only run 32X11.50 tires, cause thats all the bigger tire I need for what I do. My 258 has a holley 4 barrel, offy intake, comp cam, rollor rockers and so on, so I have the power, just don't need huge tires.|
|06-28-2011 07:04 AM|
|Trenton||also if anyone can help me with the 4.0 tb install id appreciate it. when i installed it, i swaped over all 3 sensors, only thing i didnt swap is the little housing on the side that one of the sensors go in to. Problem is when i install it as soon as i start my truck is redlines???? but if i put the original right back on it is fine again. Does anyone know whats wrong or how i can fix it? i have also heard its like the best mod for this engine, so id really like to do it. Also, is the IAT sensor relocating mod for real or is it just BS? ive seen some say its great and some say it only fools the ECU and makes truck run rich and thats its the same as buying one of those $20 chips off ebay?|
|06-27-2011 10:56 PM|
im new here, i wouldve made a new thread but wasnt sure how to??
anyway i just have a question regarding all the 2.5 posts...
why do ppl say its so slow and under powered?
Now i own a Dakota, not a Jeep. but since its the same engine and its more
popular in the jeeps i figured this would be the better site. I know the jeep and the dakota
are two total different machines but for a 4 banger truck it moves great. the mods i have done include
cold air intake, headers, downpipe, flowmaster 40, electric fan, and lower temp thermostat. i also have a
4.0 TB i have not put on yet and a set of perf. plugs, wires, dist. etc. Its also fairly peppy.
some of the vehicles i have won against in a race are 79 400 ranger, 97 dodge ram, 04 chrysler 300, 94 s10,
honda civic, etc. i also suprisingly won against my friends 09 warrior 350 4wheeler, me and him both thought
i would get smoked. I did not over exhagerate, the cloesest of them all was the 300 chrysler because i only can
win until about 80mph(when i shift to 4th he passes). anyway point of the post is im just tryin to figure
out why ppl dog the 2.5l so much?? and if anyone has any ideas or tips for my truck feel free to let me know. thanks
|04-22-2010 10:26 AM|
An all the thread stalking I have been doing over the years, I haven't seen it done.
Just googled it with little results, although I have seen some people mention that they
have seen a 2.7L done. But, that's one of those "a friend has a friend that knows a guy
that saw a guy on a forum do it".
.: Avenger Superchargers :.
A 30-percent Increase in Power and Torque?
Sorry I couldn't be more help. At this time, that may be more viable.
|04-13-2010 10:40 PM|
|kswyg001||did this stroker 2.5 ever come out of idea stage and get built?|
|05-13-2007 12:39 PM|
|BarracudaBlueXJ||Clifford performance makes cams for these engines and many other inlines. I f your old school like me they also have intakes for a 4 barrel carb, and they also list headers.|
|04-14-2007 06:25 AM|
Yes you will see 300hp for about one trip to redline and all of the oily bits will be sprayed all over the road in tiny little pieces.
|04-12-2007 11:20 AM|
|bob082484||You said there are other cams available. Ive been looking for a mild one but can only find one from Hesco. Other options?|
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