Bored Throttle Body

[135Boom]

Hey there. First Post, glad I found you guys. I have a 90 comanche with the 4.0 and was wondering if anyone had any experience with the bored throttle bodies from XJ-ARMOR.

My truck has 187k on it and was just lookin at improving the power a little and getting it to run a little more efficient. Gettin about 14-15 mpg with her right now, which is a tad lower than I was expecting. Going to go through the sensors and make sure they are good/replaced. I cleaned the TB and it has a AFE filter in it.

I also have the common high idle problem on cold start up, which sounds like the IAC sticking....probably all gummed up.

Anyway, just wondering if the $175 for a bored xj-armor TB was worth it, and if anyone had any experience. Thanks!!

 

http://www.xj-armor.com/tb.htm

[Eagle]

A bored-out throttle body might help with performance, but it won't help with gas mileage. If anything, it'll make it worse.

 

Read this thread: http://comancheclub.com/forums/viewtopic.php?t=9328

 

It starts off about exhaust pipe size, but it gets into the differences between the original 4.0L engine (which you have) and the HO. Too many owners of the non-HO version think they can make some magic, $5 tweak that will transform their engine into an HO version. Not gonna happen. The original 4.0L engine was not designed to run at high RPM, and was not designed to be a street drag champion. If your definition of "performance" is drag strip acceleration, you have the wrong vehicle and the wrong year.

 

But ... 15 MPG is worse than your gas mileage should be. Is the truck all stock? 5-speed or automatic? What tire size? Does it have the stock gearing? Is that around-town mileage or highway mileage? How do you use it, and are you heavy on the throttle or easy on the throttle?

[135Boom]

Hey, thanks for the reply. Yeah, not making a drag machine out of it, hahaha...its a jeep. Its my hunting rig. Just wanted a little more poop is all, and for it to run well. Going to be my daily driver for 2 months most likely so sounded like a pretty easy way to get some hp.

I read about those ford fuel injectors too, and think I might go that route first, as I am almost certain mine are the stock 18 year old injectors at 187k.

 

The truck is a 5spd, 4x4, short box. It has that lift kit that puts the axle below the leaf springs in the back, and longer coils in the front...so its a good 4-5 inches over stock, and its running 32x11.50 BF all terrain KO's on aluminum 15x8 wheels. Otherwise its stock. So I effectively raised an unaerodynamic brick making it even worst.....BUT....14-15 with a little city and a lot of highway seems a little low. According to what I have read, and whats on edmunds and sites like that, the 5spd 4.0 eliminator was rated at 17-22mpg brand new/stock height

[135Boom]

....in trucks past, raising it a few inches and putting on a little bigger tire did not loose that much mpg. Truck runs well, doesnt burn oil, doesnt blow anything out the back on start....but I suspect it running rich, cause its goin threw the fuel, haha. I put an afe high flow panel filter in the box, and put bosch platinum +4's in. Thats about all I have done besides change all the fluids and a fuel filter.

 

Only problem I am having is the high idle 2200rpm on cold start...something is sticking. then relatively high idle most the time once warm at about 900-1100rpm. Pretty sure its the IAC, as I have checked vacuum lines. Its something that changes once warm though...like something is getting stuck, then warms up and free's up. Weird.

[Pete M]

Stock gears?

 

Stock gears and 32s will bring on the suck, both in power and mpg. A regear or swap to junkyard axles with a better gear ratio will provide you with the results you seek. :D

[135Boom]

...I'm not sure if it has stock gears or not. Havent had the truck very long. I think something got messed with cause at 65mph it's at 2k rpm, and I am actually (according to my new tacoma following it) doing about 62mph.....which would not make sence because I have TALLER tires on the jeep than stock, which means it should be indicating slower than actual speed. So I wonder if I do have aftermarket gearing?

[Eagle]

The truck is a 5spd, 4x4, short box. It has that lift kit that puts the axle below the leaf springs in the back, and longer coils in the front...so its a good 4-5 inches over stock, and its running 32x11.50 BF all terrain KO's on aluminum 15x8 wheels. Otherwise its stock. So I effectively raised an unaerodynamic brick making it even worst.....BUT....14-15 with a little city and a lot of highway seems a little low. According to what I have read, and whats on edmunds and sites like that, the 5spd 4.0 eliminator was rated at 17-22mpg brand new/stock height

Has the speedometer been recalibrated for the larger tires? Did you re-gear when you put in the lift and big tires?

 

Frankly, 15 MPG with 32" tires and a 5" lift is probably about as good as you have any right to expect.

[offroader461]

DO NOT BUY FROM THEM...THEY ARE NOT IN BUSINESS...I GOT SCREWED OUT OF $120 WHEN I BOUGHT THERE MAP MODIFYER...I

filed a complaint and found out hes out of business but his webpage works....trust me HORRIBLE CUSTOMER SERVICE

[135Boom]

wow....thanks for the reply....that would have sucked! Any other people out there doing a nice bore job on the stock TB incase I go that route later?

 

Whats a MAP modifier? Does that relocate the MAP sensor from the intake manifold to somewhere else? Ever find someone else that had something without having to replace the whole intake?