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06-23-2011, 09:38 AM

#31

Gee oh Dee

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Year: 1987

Engine: Check

Quote:

Originally Posted by Cherokee89sport

But doesn't regearing throw off your speedometer?

Simple fix.

Most even forget the speedo alltogether of they have GPS.

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06-23-2011, 09:42 AM

#32

SeriousOffroad

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Not a good idea since the VSS output is used to determine shift points.

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06-23-2011, 09:51 AM

#33

98jeepsrt6

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Year: 1998

Model: Cherokee

Engine: 4.0 L6 Srt

Sorry to thread jack, OP hasnt returned yet so this may be a good question for some..

I am at stock height, stock wheel size and tires.. How would i be able to lower my highway rpms.. i dont know the speed im going (speedo gear gets chewed up, havent been able to figure out why) but around 2000rpms i figure im rolling at about 65-70 mph.

I always thought about getting a different valve body(supra) that has a 5th gear.. or go ax15 swap..

what gearing should i be interested in to achieve the same goal without swaping trans or parts??

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06-23-2011, 10:02 AM

#34

TheJerm

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Year: 1995

Model: Cherokee

Engine: 4.0 HO

anything lower than 2k rpms its going to be downshifting all the time on the highway. AX15 FTW!!! Still cruise at 2k rpms

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06-23-2011, 10:14 AM

#35

98jeepsrt6

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Year: 1998

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so theres no way around that?

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06-23-2011, 03:28 PM

#36

TheJerm

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Year: 1995

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not sure why you would want to...

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06-23-2011, 03:42 PM

#37

ericfx1984

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Year: 1996

Model: Cherokee

Engine: 4.0HO

Quote:

Originally Posted by ol"blue

You can't go that big on the TB without getting bigger injectors, and then you won't be getting better mileage. You can't have it both ways, a lot more power and more mileage too. It takes more fuel to make more power.

that is not ALWAYS the case... you can make fuel atomization more efficient... better quad pintle injectors, and surface turbulence on the intake side...

this explains surface turbulence
http://www.metricmechanic.com/catalo...turbulance.php

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07-10-2011, 11:58 PM

#38

DailyDriven

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Year: 1996

Model: Cherokee

Engine: 4.0L High Output

Quote:

Originally Posted by Screwd up 6

I would think the catback exhaust had more postive performance results than a throttle body spacer. To my knowledge, experience and research on TB spacers, they are about as useful for horsepower as a K&N sticker

LMAO!!!

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07-11-2011, 03:14 AM

#39

Slick761

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Year: 1990

Model: Cherokee

Engine: The venerable 4.0

Quote:

Originally Posted by 98jeepsrt6

hi guys,
Regarding HP.. on 4.0L i6
Your not going to get much from all of these mods.. Intake, throttle body, manifold, headers, high flow exhaust, electric fans, a/c delete, injectors and what ever else you can think of that bolts on. I know this from experience. Im more of a gear head than an off road enthusiast. (Will be with next xj)

Anyways ive done most of these, actually all of the above mods other than 99 intake mani. With that ive only noticed better throttle response, and much better top end accl. and a couple mpgs to go with it.

Three ways to get HP in a jeep is either to 1. STroke it 2. Swap it 3. FI (Forced induction)

Also im running stock height, stock sized wheels/tires, and stock gears.. so really your not going to get much out of it.

on the later Cherokee it is hard to het performance with just bolt ons. The factory computer runs tight parameters.... your a gearhead so you probably know about the early mpi mustangs running speed density injection..... different set up same results. You can't just turn up the.fuel pressure.on these puppys with those mode and get the results you're looking for. Us renix.guys have it made. Simple.adjustable fuel regulator and adjustable map sensor with a mild cam and head porting and the intake and exhaust goodies can put down 240+ at the flywheel. Look up a guy by the name dino saava on Google. He has hilt and tested tone of good mods and has lots of good info. http://www.jeep4.0performance.4mg.com/

Last edited by Slick761; 07-11-2011 at 03:22 AM.

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08-05-2011, 04:48 PM

#40

Kamaran

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^^ Exactly why I'm happy to own a Renix. Only downside I see is the peugeot.

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08-05-2011, 05:58 PM

#41

Slick761

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Year: 1990

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Quote:

Originally Posted by Kamaran

^^ Exactly why I'm happy to own a Renix. Only downside I see is the peugeot.

I guess I'm just lucky lucky lucky... aw4.

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07-04-2012, 03:08 PM

#42

89jeepxj

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Year: 1989

Model: Cherokee

Engine: 4.0L

the most difference in my opinion is a comp offroad cam kit get about 300hp and 310fpt. need to run amsoil high zinc oil to make the cam last longer. gains 5mpg when driving normal but with the throttle down it takes alot of go go juice haha

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07-04-2012, 04:04 PM

#43

Slick761

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Year: 1990

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Engine: The venerable 4.0

Quote:

Originally Posted by 89jeepxj

Where did you get those numbers? 300hp and +5 mpg? That's a little unrealistic especially for a cam change. Maybe a stroker with a cam set up for low end torque and a small turbo. You aren't getting 300hp out of a 4.0 with a cam change. Please tell me what cam you're talking about I'd like to check it out.

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05-20-2013, 03:46 AM

#44

4wheeldrivenewbie

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Year: 1989

Model: Cherokee

Engine: 4.0 straight 6

I know this is an old thread but who gave the idea that any coldair intake in the world would give u a noticeable difference in hp. they are a waste of money and most sit right above hot headers unless u have a Nissan skyline with a turbo something like that your wasting money on cai they do almost nothing.

Add a magnaflow or flowmaster cat back better spent money and u will get a nice sound out of it.

There are really no mods for renix that do anything I have yet to see a renix that does 190hp