JEEP question - 4.0 vs 4.0HO

im so glad you posted about that ecu chuck as it sounds like it
wouldn't be worthwhile to do the HO conversion. i did a little
snooping around and found out some info about it. Prod #4529334 right?
i even found a place where i can buy one thats never been used for
$450. which is nice bc i was expecting more than that for the HO
conversion. only problem i'm having is that i can't find any power
gain info on it. the only mods ive done are ram air intake, throttle
body spacer, borla headers, magnaflow high flow cat, and i chopped the
muffler. what do u think that i could expect to gain from the ecu with
this setup? i am also thinking about buying a bored out throttle body.
do you think that would help any? i know it's gonna hurt my wallet
though bc it says it needs premium fuel which is about $2.25/gallon
here now. obviously you have experience with the ecu since you own
one, so my other question is how hard is it to swap out? it says it's
for offroad racing applications so i doubt i am going to be able to
pass emissions with it. i still have quite a few more years until my
jeep is emissions exempt so i figure every year i will have to put the
old one back in before i go to get the tests done. any other mods you
know of for my jeep that will give significant power gains short of
major stuff (stroker,blower,etc)? anyway, please let me know if u have
any info about how much power i could expect to gain from it. thanks
alot chuck!

i've been running it on my stock engine ('87 4WD) for a couple of months
now, with the following conditions: it's my daily driver, and I use 87
octane, so I probably don't get as much benefit out of it as I could be. in
my case I wouldn't say that it gives more power, but it's more available
power... seems to be a little quicker from a dead stop, and will pull long
hills much better. I average about 14 MPG with the computer, 33" tires, and
4.56 gears with an automatic tranny. It gets a little better on the
highway- 16-17 MPG or so.

The research I've done on it states that it alters the timing curve and fuel
maps (injector pulse width, etc.). I've also noticed that it says 'racing
use only', 'not for towing', etc. Like I mentioned, I run 87 octane, and it
passed the CA smog check with no problems. I should mention that I failed
previously, and replaced the cat at the same time. either way, the
emissions were *very* low (well below average).

Installing it is not particularly hard, but it's uncomfortable you have
to kind of twist yourself under the dashboard (the computer is located
sort-of behind the radio, just to the right of your right foot/gas pedal).
when I get home tonight, i'll peek under the dash and get the part number
off of it and post here.

short of major mods (and what you've done so far), I've heard that the
long-tube Mike Leach/Mopar performance headers will get you good bang for
the buck. you could also port your head & intake, particularly the exhaust
ports.

Dino Savva has a great low-to-mid-buck performance site here (as well as
info on stroking & supercharging): http://www.jeep4.0performance.4mg.com/

have fun!
Chuck


"James Morrow" > wrote in message
om...
> im so glad you posted about that ecu chuck as it sounds like it
> wouldn't be worthwhile to do the HO conversion. i did a little
> snooping around and found out some info about it. Prod #4529334 right?
> i even found a place where i can buy one thats never been used for
> $450. which is nice bc i was expecting more than that for the HO
> conversion. only problem i'm having is that i can't find any power
> gain info on it. the only mods ive done are ram air intake, throttle
> body spacer, borla headers, magnaflow high flow cat, and i chopped the
> muffler. what do u think that i could expect to gain from the ecu with
> this setup? i am also thinking about buying a bored out throttle body.
> do you think that would help any? i know it's gonna hurt my wallet
> though bc it says it needs premium fuel which is about $2.25/gallon
> here now. obviously you have experience with the ecu since you own
> one, so my other question is how hard is it to swap out? it says it's
> for offroad racing applications so i doubt i am going to be able to
> pass emissions with it. i still have quite a few more years until my
> jeep is emissions exempt so i figure every year i will have to put the
> old one back in before i go to get the tests done. any other mods you
> know of for my jeep that will give significant power gains short of
> major stuff (stroker,blower,etc)? anyway, please let me know if u have
> any info about how much power i could expect to gain from it. thanks
> alot chuck!

i've been running it on my stock engine ('87 4WD) for a couple of months
now, with the following conditions: it's my daily driver, and I use 87
octane, so I probably don't get as much benefit out of it as I could be. in
my case I wouldn't say that it gives more power, but it's more available
power... seems to be a little quicker from a dead stop, and will pull long
hills much better. I average about 14 MPG with the computer, 33" tires, and
4.56 gears with an automatic tranny. It gets a little better on the
highway- 16-17 MPG or so.

The research I've done on it states that it alters the timing curve and fuel
maps (injector pulse width, etc.). I've also noticed that it says 'racing
use only', 'not for towing', etc. Like I mentioned, I run 87 octane, and it
passed the CA smog check with no problems. I should mention that I failed
previously, and replaced the cat at the same time. either way, the
emissions were *very* low (well below average).

Installing it is not particularly hard, but it's uncomfortable you have
to kind of twist yourself under the dashboard (the computer is located
sort-of behind the radio, just to the right of your right foot/gas pedal).
when I get home tonight, i'll peek under the dash and get the part number
off of it and post here.

short of major mods (and what you've done so far), I've heard that the
long-tube Mike Leach/Mopar performance headers will get you good bang for
the buck. you could also port your head & intake, particularly the exhaust
ports.

Dino Savva has a great low-to-mid-buck performance site here (as well as
info on stroking & supercharging): http://www.jeep4.0performance.4mg.com/

have fun!
Chuck


"James Morrow" > wrote in message
om...
> im so glad you posted about that ecu chuck as it sounds like it
> wouldn't be worthwhile to do the HO conversion. i did a little
> snooping around and found out some info about it. Prod #4529334 right?
> i even found a place where i can buy one thats never been used for
> $450. which is nice bc i was expecting more than that for the HO
> conversion. only problem i'm having is that i can't find any power
> gain info on it. the only mods ive done are ram air intake, throttle
> body spacer, borla headers, magnaflow high flow cat, and i chopped the
> muffler. what do u think that i could expect to gain from the ecu with
> this setup? i am also thinking about buying a bored out throttle body.
> do you think that would help any? i know it's gonna hurt my wallet
> though bc it says it needs premium fuel which is about $2.25/gallon
> here now. obviously you have experience with the ecu since you own
> one, so my other question is how hard is it to swap out? it says it's
> for offroad racing applications so i doubt i am going to be able to
> pass emissions with it. i still have quite a few more years until my
> jeep is emissions exempt so i figure every year i will have to put the
> old one back in before i go to get the tests done. any other mods you
> know of for my jeep that will give significant power gains short of
> major stuff (stroker,blower,etc)? anyway, please let me know if u have
> any info about how much power i could expect to gain from it. thanks
> alot chuck!