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Performance Upgrades

Starboard M

NAXJA Member
NAXJA Member
Location
WA
Ive been looking through all the old threads about how to get those few extra horses, and I have seen a lot. But Im looking for more. I recently got a '89 non HO Cherokee that I might be dd as the other cherokee is being somewhat tempermental. So what do you guys, and girls, recomend that I add. Keep in mind Im on a tight buget, so things are going to be tight. So no strokers, or anything major like that.
-Synthetic oil
-High performance spark plugs
-Flowmaster 40 series
-K&N filter
-Spark plug wires
-Throttle body cleaner


Anything else? Cheap is always good.....
 
good list, but a high mileage rig and synthetic oil usually means that
your Jeep will be marking it's territory a lot more
 
Lodi Jim said:
good list, but a high mileage rig and synthetic oil usually means that
your Jeep will be marking it's territory a lot more
I could care less if it does that. Do you have to get a different oil filter for syntetics? Anyone else have any ideas?
 
No special filter needed for synthetics. I use a NAPA Gold. Wix, Puralator Pure One, Baldwin and Hastings are the same filter or equal to. GM and Ford filters are suppose to be good. Mobil One filters are top rated, but near twice the price. Castrol use to make a simular filter to the Mobil One filter, but not as high priced. Synthetic may make your engine leak more oil, if your seals aren't good. Switching back to conventional oil won't help.
Tom
 
i have always used the k and n filter but at 10-12 bucks a pop those do add up... they are by far my fav in easy installation with 1 inch nut, durability, and maintaing proper oil pressures and eliminating dry starts
 
also, i have added 2.5 inch flowmaster 40 exhaust recently which is great for sound and performance, tb spacer and intake (rusty's air tube + kandn filter). These are easy on the wallet and bolt on within minutes...the exhaust required some custom fab but was overall worth it... i mated it with a 2.5 in 2.5 out zj cat which i torched off for 10 bucks at a junkyard... i had the platnium 4+ plugs but i dunno cant really tell much difference... i just installed at 80000 miles the accel tune up kit from 4wd for 70 bucks. This in my opinion is a great upgrade. Bolt on performance is hard to beat with so many options availible for all era cherokees.
 
I have put several things on my other cherokee that is a 89 as well. I have heard that TB spacers do almost nothing for the non HO engines. I would rather spend the money on other stuff. Dr. Dyno, I have seen your site and I got a lot of my ideas from there. However, most of it is rather expensive. I am not able to throw lots of money into this right now. I am going to do the Flowmaster 40 series, but might try and get something louder. I am going to get the Rustys air tube and the larger K&N filter. I am planning on the Platinum 4+ when I do the wires and plugs.

Sorry for putting this in the wrong place
 
Starboard M said:
I have put several things on my other cherokee that is a 89 as well. I have heard that TB spacers do almost nothing for the non HO engines. I would rather spend the money on other stuff. Dr. Dyno, I have seen your site and I got a lot of my ideas from there. However, most of it is rather expensive. I am not able to throw lots of money into this right now. I am going to do the Flowmaster 40 series, but might try and get something louder. I am going to get the Rustys air tube and the larger K&N filter. I am planning on the Platinum 4+ when I do the wires and plugs.

Sorry for putting this in the wrong place
Trust me the 40 is as loud as you want the next step would be straight pipe
 
robz95xj said:
Trust me the 40 is as loud as you want the next step would be straight pipe
From what I have heard the Super 40 is louder. I have the 40 on my other Cherokee and like it, but to me it isnt all that loud. Might just be my young ears and having friends with mussle cars :laugh3:
 
i'm going to sound crazy to most everyone here, but trust me (my few post's is a lie if you rate that to how much bull crap knowledge i have), go back and find out from the dealer what the part number and brand of plugs came stock in your jeep. this is one of the biggest mistakes that people make when trying to starve power from their motors. that plug is designed for that specific motor and the way it runs and the fuel the owners manual says to use, and any diviation to the plug will rob power. however, different wires, upgraded cap, rotor, and all that other crap will add power. also, take into consideration, that if you do MAJOR upgrades to your motor, like bigger injectors, stroke, cam, all that internal crap, you'll have to be on your own to find the best plug. most good stroker companys can tell you what has worked best with the type of mods and such, but if you're just doing cheap bolt on stuff, stick with stock plugs and the dealer recommended octane.

as far as exhaust...... headers (yeah, not cheap, but well worth the money), high flow cat, high flow muffler, but if you go all high flow stuff, you might consider sticking with a smaller sized exhaust as too little backpressure also robs power.

good luck, power is efficency if done right...
 
53guy said:
as far as exhaust...... headers (yeah, not cheap, but well worth the money), high flow cat, high flow muffler, but if you go all high flow stuff, you might consider sticking with a smaller sized exhaust as too little backpressure also robs power.


Not quite true. Backpressure is bad for everything. It's that you want to keep exhaust velocity. Otherwise you lose torque. I think a 2.5" exhaust would be the perfect addition to any slightly modded XJ, just keep the routing uncluttered and make it mandrel bent.
 
JeepSpeed said:
Not quite true. Backpressure is bad for everything. It's that you want to keep exhaust velocity. Otherwise you lose torque. I think a 2.5" exhaust would be the perfect addition to any slightly modded XJ, just keep the routing uncluttered and make it mandrel bent.


WORD

FUNKYTEE5
 
rock rash said:
TB spacer...dont do the jet chip though. heard alot of bad things about them...


Ill disagree for sake of arguement, I have it in mine and the only down fall I have with it is when I do a steam clean its seal doesnt hold well. I have noticed alot umph from it.

On top of the chip I installed the 4.2l crank and cam, bored throttle body and spacer with the forced air intake. All in all im really impressed with the combo. On dyno (its been a while) I think it was running in the 260 hp and 280t range. If I can find the results on the old computer Ill post those up to for you all.
 
JeepSpeed said:
Not quite true. Backpressure is bad for everything. It's that you want to keep exhaust velocity.

thank you for correcting me. i'd alwasy been taught that it was backpressure, but now with that info, it makes much more sense...thanks
 
From what I have read, the I6 likes a bit of back preasure. I think 3.5'' is about the recomended size. Badcop, you have that chip on a modified engine, right? What he is talking about is a slightly moded engine. Thanks for the help guys
 
Starboard M said:
From what I have read, the I6 likes a bit of back preasure. I think 3.5'' is about the recomended size.

No engine likes backpressure, and 3.5" is definitely NOT the right exhaust size. :)
The exhaust pipe size should be optimized to maximize exhaust gas velocity across as wide a rev range as possible while minimizing backpressure.

Pipe too small = too much backpressure at high rpm
Pipe too big = too much backpressure at low rpm due to lack of scavenging

Optimum pipe size = 2.25" for 4.0 that's stock or has only external bolt-on performance mods, 2.50" for 4.0 with ported head/performance cam or 4.5-4.7L stroker.
 
Opps. that was suposed to be 2.5''. I could have sworn Ive seen it somewhere that the engine needs a bit, but I guess not.
 
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