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Discussion Starter · #1 ·
Well here's my problem. I have a 94yj which is mostly stock other than a 4" lift and lockers with 33"s. I still have the 2.5L in due to the fact of the jeep only has 61,000 miles. The thing runs like a top, but as you probably aready know it lacks in the power area. I have installed the electric fan, the K&N air system, and the better exhaust. But still can't get out of my own way when traveling. I have researched installing a turbo system which in supposed to increase hp by 40%+. I want to keep the jeep to be a daily (or frequently) driver. To make a long story short will I be wasting my time with the turbo upgrade? Has anyone done this? I know most will say "you could of had a V-8", but I really don't want to do that.....yet.
 

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Well here's my problem. I have a 94yj which is mostly stock other than a 4" lift and lockers with 33"s. I still have the 2.5L in due to the fact of the jeep only has 61,000 miles. The thing runs like a top, but as you probably aready know it lacks in the power area. I have installed the electric fan, the K&N air system, and the better exhaust. But still can't get out of my own way when traveling. I have researched installing a turbo system which in supposed to increase hp by 40%+. I want to keep the jeep to be a daily (or frequently) driver. To make a long story short will I be wasting my time with the turbo upgrade? Has anyone done this? I know most will say "you could of had a V-8", but I really don't want to do that.....yet.
I HAVE A 93 WITH 35" TIRES & 4:88 GEARS. HAS PLENTY OF POWER WITH THIS SET UP. DON'T THINK I WOULD GO TO THE TROUBLE OF A TURBO WHEN A V-8 SWAP WOULD PROBABLY BE EASYER AND CHEAPER. DO GEARING FIRST.
 

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Unless you are prepared to tune it, and have knowledge of what you arein for, don't do it. Its one thing to tune for wide open throttle/power, which is usually what car guys want. But tuning part throttle boost can be a real bitch. Especially in a low rpm/high load application.
 

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Can't lose with 42s
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X2 boost enrichment throughout the powerband is a PITA to tune... Not saying it can't be done, anythings possible
 

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I make turbo's and I promise that you will be happy with the outcome of the hamster. Then if you upgrade your drive train or anything else it will make more the differance.
 

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Discussion Starter · #13 ·
Well guys, I have done some research and talk with some local experts and the turbo project is a go.
 

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LOL, ya tuning is a bitch so far. I have a stand alone that is touchy on startup but runs great. I was running about 10 lbs of boost then decided to get stupid and try for max boost pressure. Well, long story short and a rebuilt motor later, boost spike of 21lbs is not good for the 4.0. Fun for about 10 sec but not good.

If you really want to get serious with it, the wideband O2 sensor will run you more than 300 alone. The fuel management will be another easy 300-500. So yes, putting the turbo in is cheep, but tunning it isn't.

If you want it to be daily driven and mostly reliable, run about 5lbs of boost and put in bigger injectors. I have 29lbs and 5 lbs of boost and put it back to stock fuel management and it works just fine. You have to only watch out in certain spots on the throttle to make sure it doesnt lean out too much. I would for sure get a wide band o2 also.



Thats my gauge pod i built. Changed the narrow band o2 to an inovate wide band o2 though.

Def worth putting in though. I probably could have done a v8, but this was different and a fun project. Nothing like 4 wheel drifting now with 35's and stock gearing.
 

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LOL, ya tuning is a bitch so far. I have a stand alone that is touchy on startup but runs great. I was running about 10 lbs of boost then decided to get stupid and try for max boost pressure. Well, long story short and a rebuilt motor later, boost spike of 21lbs is not good for the 4.0. Fun for about 10 sec but not good.

If you really want to get serious with it, the wideband O2 sensor will run you more than 300 alone. The fuel management will be another easy 300-500. So yes, putting the turbo in is cheep, but tunning it isn't.

If you want it to be daily driven and mostly reliable, run about 5lbs of boost and put in bigger injectors. I have 29lbs and 5 lbs of boost and put it back to stock fuel management and it works just fine. You have to only watch out in certain spots on the throttle to make sure it doesnt lean out too much. I would for sure get a wide band o2 also.



Thats my gauge pod i built. Changed the narrow band o2 to an inovate wide band o2 though.

Def worth putting in though. I probably could have done a v8, but this was different and a fun project. Nothing like 4 wheel drifting now with 35's and stock gearing.
It will run with larger injectors and no adjustable MAP? I figured it would run pig rich anywhere but maybe WOT. Are you pulling timing at all?
I figured I could use 19lb injectors so the computer stays happy, and then add fuel under boost with an FMU. It should work well with 5-8 psi I think.
 

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timing is all stock because i cant adjust it with a 01 tj. The computer adjusts timing all the time based on knock (which i haven't gotten so far) No adjustable map is needed because when you are not in boost the stock pcm actually works really well and keeps the a/f right at 14.7 up to about 5 lbs using the stock o2's to adjust fuel injectors duty cycle. WOT runs great because its open loop and dumping max fuel into it. I can probably run 8lbs on WOT but getting to it is the problem you will get lean knock. I guess there are a lot of things you can do. A FMU like you said will probably work. Thing is with th FMU is relays on getting the boost signal before it increases fuel pressure. By that time it may be too late and you will already be lean. With the stand alone fuel, you can tune it to predict the fuel it needs at a specific rpm and map. Honestly with about 5lbs, bigger injectors, a wideband it will make a whole new jeep. If you're ever coming down to Kalamazoo, hit me up and come check it out.

come summer when i dont drive the jeep as a dd, i'll hook up the stand alone again and try some more tuning and run up at 10 psi again. Just for winter i dont wana be fucking with it when i have to get to work in the morning and the cold.
 
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