what engine upgrades are bolt in on a 4 banger

thanks for ur input

a 4.0

seriously?
there are headers, TB spacers, bored TBs, intakes, K&N filters, cams, and some other small things.

If youre lacking power go for deeper gears. My friend rides a YJ on 36" swampers with 4.88 gears and a 2.5 and he does really well for himself

*Cliff Notes*: With re-gearing, I think you'll find the 4 banger is as strong as you need, and the milage is envious.

If you want just a little cost-effective power, try K&N filter and intake, and headers and cat-back exhaust.

No matter how much $$ and parts and time you throw at a 2-valve OHV 4-cyl 2.5 (152 cid), you'll never get more than 160 bhp at the crank. The low-end torque will still be low, and the engine durability will be suspect 'cuz it's maxed out.

A strong used 4.0 from a junkyard, with matching tranny and new radiator, will give you about 185 hp. Dependably.
Better bang for the buck, overall.

With 33's and stock gears, you are really hurting for deeper gearing; at least 4.10's.
With a manual tranny and lockright, you have axles just waiting to break on the right rock.

Do the d44 with lower gears and a locker or ls. Then matching gears and locker in the d30.

if its an '89 2.5 5sp he should already have 4.10's

You can sorta bolt a turbo on. There's a couple folks on here that could send you in the right direction if you're willing to do this.

I like the 4 cyls. good little motors that you can't ever seem to hurt.

4.88's work real well for my 33's. the short stroke (3.19") on the 2.5 lends itself well to higher RPM than a 4.0...it is true that the HP is limited by the displacement..it's all about volumetric efficiency and heat.

If you have the ability to change the camshaft and valve springs, Hesco has a cam kit, that combined with headers, a free flowing exhaust and ignition mods will make a real performance gain you can feel... but the gearing change will have more effect than the engine mods.

I disagree with one thing about the 2.5L I think it can be built to near 4.0 HP levels but it want be bolt on. There are superchargers available and seems liek I read a 4.0 throttle body will bolt up to some of them. Not sure what years. A cam is the best bang for the buck in my book. You can still find them on Ebay every now and again.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2427149379&category=33614

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2427417454&category=33614

buy a wrecked cherokee with a 4.0L and swap the whole drivetrain/wiring harness over.

it's 100% bolt-in.

I'm doin this to my MJ right now, the ONLY modification I need to make is the rear driveshaft (because I can't use the cherokee one) other than that, EVERYTHING is bolt-and-go.

well the 4 banger is going, so i figure a bigger engine is a good choice

4.0L
4.2L

you could steup up from a 2.5L to a pair of squarrels?

KarmirXJ 4.0L 4.2L

Click to expand...

How pray tell is that a bolt on for the 2.5L? There are only two engins that I know of that will bolt in place of the 2.5L without Major work! And that is the 3.1L and the 3.4L. Where are you in S.C. Jimmy? It woudl also help to know what year 2.5L you have, b/c there are three different 2.5L's that were put in the XJ. Carberated, TBI and MPFI.