want more horsepower

[cal]

You mean it gets them up to HO power?


I didn't know that actually. What sort of power are you getting out of headwork and such? I had an 88 for awhile but sold it for my TJ 10 years ago.

I dunno numbers, I run a renix stroker with a big cam and head work, but I'd be willing to bet I am putting out over 300.

Eric Filar was getting near 300 out of his jeepspeed 4.0 with a cam and a lot of head work, but he was using an aftermarket computer too.

I think one of the bigger things you can get away with is tweaking your MAP to increase the injector pulse at WOT. It wouldnt have much effect under normal driving, so the HO ECU would not program around it.

 

[cal]

anyone care to list the HiPo 4.0 companys that they know of? im new to the 4.0 scene so i cant contribute at the moment.

look at:

Hesco - from tin to complete strokers
505 Performance (big internal stuff, up to 700 horsepower kits)
Banks (now working on 4.0 turbo kits) headers, intakes
Jeepers and Creepers (aftermarket throttle bodies)
Clifford - cams, headers, etc
Mopar Performance - a lot of everything, if you dig long enough
Comp Cams - cams, low compression lifters, etc
Jet - modified computers renix thru 01
Keith Black - out of the box stroker pistons
Precision Machine (cams and engine kits)
MSD makes renix ignitions

There have been a lot of crazy things made over the years.. I have a box in the garage for a Mopar Performance distributor for renix that lets you adjust the timing a bit, a Clifford water pump for the 4.0 that is high flow, and blue printed (wtf?)..

The problem is jeepers are too cheap to actually buy high end parts when they release, so vendors stop making them again instead of getting the volume to bring the price down.

 

[robsjeepxj]

I did like the bigger throttle body and 2.5" flowmaster exhaust after I did it but honestly regearing to 4.56's made the biggest difference in all around performance for me. The bigger tires completely killed all my power, the right gearing fixed that real quick. The engine was fine I just didn't have the it set up properly for the lift and tire size I was using. It's good now, lots of get up and go.

 

[XJ4AllSeasons]

I was doing some research and found that if you get an intake manifold from a 99 and up, a throttle body from a 91 - 95 you will increase hp and possibly mpg.
Does anyone think the same or know any different?

 

[cal]

I was doing some research and found that if you get an intake manifold from a 99 and up, a throttle body from a 91 - 95 you will increase hp and possibly mpg.
Does anyone think the same or know any different?

99+ intake does have some slightly improved design over the earlier ones. Just doing it alone, you won't notice much - but people doing dyno tests on built 4.0's and strokers going to a late model intake have gotten 2-3 horsepower out of it.

Upgrades increase the percentage of power. Each one that you do increases not only your base power, but how much you gain from each other upgrade you have done. (..in theory, at least). The late model intake is an improvement, but by itself not really all that much.

the 91-95 throttle body isnt really all that special by itself, but any increased flow throttle body will give you gain potential.

 

[1990JEEPXJ]

so i must ask cal, what would be good power adders for a stock renix 4.0?

 

[cal]

so i must ask cal, what would be good power adders for a stock renix 4.0?

in about this order?

better injectors (this does not necessarily mean bigger)
bored throttle body
good 2.5" catback exhaust
good header
HO head + intake + throttle body
mild stroker budget stroker
http://www.shop.505performance.com/product.sc?productId=272&categoryId=25

 

[max419]

good header
HO head + intake + throttle body
mild stroker budget stroker
http://www.shop.505performance.com/product.sc?productId=272&categoryId=25

I really wanna do this

 

[Boost_Retard]

What about all this tuner crap like the super chips stuff, does it actually help after a lift and tires?
the edge trailjammer looks like a decent kit, but i dont think you can do any of the extra stuff that you can with one of these tuners? (like the superchip)

 

[WAM174]

in about this order?

better injectors (this does not necessarily mean bigger)
bored throttle body
good 2.5" catback exhaust
good header
HO head + intake + throttle body
mild stroker budget stroker
http://www.shop.505performance.com/product.sc?productId=272&categoryId=25

So who makes a good header and exhaust system for a 97 XJ? I'm finding mostly catbacks. The headers are all for TJ's. I'm looking for things to do now, which will also work later with a stroker. Is Rusty's intake okay with the 9" cone filter? Where can I buy a bored OE throttle body? I don't want an aftermarket TB that won't pass smog inspection.

 

[gradon]

The fastman: http://www.thefastman.com/Throttlebodies40.asp and Jeff Leigh: http://www.strokedjeep.com/ do good jobs on TBs. Borla makes good headers and cat-backs. 505 has some headers I'm curious about.

 

[old_man]

Check out BoostWerks. He is a sponsor and a neighbor. He sells the slickest turbo setup I've seen. His craftmanship is second to none.