alright well it seems like I have some a few solid directions to possibly take. I'm leaning towards just doing the injectors though.
The Header I bought is a Gibson GP400. its made of 14 gauge 1.5" tubing. I just got the chrome plated version.
My wife has just informed me that her mom is giving me her '92 xj to do with what I want. And to take that one step further my wife is encouraging me to do a full build on it. soooo... I believe I will be saving some cash for this upcoming project. My plans so far involve..
- GM 350 Small Block engine conversion with a 700R-4 transmission
- Long Arm Suspension Lift (around 8.5" is the goal)
- 35" Swamper Tires
- Some custom fab body parts (fender flares, rocker guards, bumpers, etc..)

The best part about this whole thing is the wife in encouraging it despite the anticipated thousands of $ it will cost. I'll be sure to document the whole process and I'm sure I will be on here with several questions along the way.

 

When I owned a 300zx, I remember there being a consensus in support of smooth polished exhaust port (headers also provide about 24hp on those cars), and the equivalent of 80 grit for the finish on the intake. The theory seems to be that the rougher surface prevents the air from "sticking" to the walls.

 

I was told that it was to save money on the production end of things but no theory to back it up...

 

ls1 swap full cage and bigger axles should help alot lol

 

i head the little spinny things that go in your throttle body give u between 15-20 hp, might give that a try??

 

tornado air? they really dont do much but maybe give you an extra 2mpg?

 

those things are bs!

DONT BUY THEM


they do not spin well and just impead airflow more than do anything

 

I would recommend just giving the '99 a tune up with quality cap, rotor, wires and plugs. Make sure you have clean fluids and filters in the Jeep and call it good.

I don't think the 703's are the right injectors for a '99. I installed 784's in my '99 and while it seems to have helped with smoother idle and a little better throttle response, it didn't make any improvements in fuel economy or overall performance, that I can tell.

 

Thank you for saying this!!! 703's WILL NOT WORK in a 99. You have to use Chrysler 784's or Ford 789's. Either work, I prefer the 784's. They can be found in a 97-01 Stratus/Breeze/Neon with the 2.4. You will not see a MPG increase, but you will get better throttle response and a smoother idle. After you do the swap make sure to reset your ecu. Otherwise you'll run rich. If you want to know how to do it, go here.

 

i warped my head and took it to a shop and macon and they shaved it down and port and polished my head for 50 bucks. i think thats a good deal

 

Decrease in mpg you mean.

 

Questions.

Would you calculate the reduction in compression ratio that results from removing that much material from the combustion chamber in the head? How would you get it back?

Would you take into account the reduction in air velocity through the intake manifold and consider that you could possibly reduce the combustion efficiency by opening up the ports that much?

 

Correct.. I was joking. All those things do is limit air flow.

 

I did not reset my computer, but I did notice that right after installing the 784's, my vehicle did run rich. I consulted with several very knowledgable technicians about dumping the adaptive memory, which is what resetting does.

The concensus of opinion was that the computer reset was optional. The computer constantly changes settings anyway based on sensor inputs. The reset would cause the computer to revert to factory preset parameters which may or may not be closer to where the computer wants to be with the different injectors.

I have noticed a steady improvement in fuel economy since I installed the 784's. When I first installed them, I was getting about 16mpg mixed city and highway and the last fill-up was closer to 18mpg. I have also installed a new pre-cat O2 since then, which might help with fuel mileage.

 

Guarantee that the O2 is what helped your mpg. Resetting your ECU allows your computer to "relearn" the necessary fuel trim levels based on how you drive over the next 50 warm up cycles. Whoever said it was optional for you to still get the best results is, and I mean this honestly, a moron. You're supposed to reset your ECU after any and every change to air/fuel mixture amounts. That would include any intake, TB, exhaust, injector, and/or cylinder modification.