ok, i know ive read this on here but im stuffed if i can find it know lol

i run a 1993 4.0 ltr xj, and have read that a later inlet manifold will realease more bhp.

1, the question is what was the years of the jeep that the manifold i need is fitted to?

2, what are the ford injectors i need? and do i have to mod anything to fit them?

3, im already using a throttle body spacer, if i get a bored out throttle body what size should i want it?


your input will be greatfully appreciated

john

 

The intake manifild you want is from a 99 or newer 4.0 from a Cherokee or Wrangler. Not sure about the Ford fuel injectors. I do know that if you can acquire the manifold from a 99 or newer 4.0 with the original fuel injetors in it, they are still even better than the original injectors that you have in your older 4.0.

 

Go with a 62mm bored out throttle body.

 

i read somewhere that the ford injectors were overkill unless your doing a lot of mods i.e. stroke or supercharge it. I think it kills your gas mileage if you go too big. I'd go with the newer 99 injectors.

you need to mees with bracketry that bolts to the manifold as well. maybe this write up will help... http://www.go.jeep-xj.info/HowtoIntakeManifold1.htm

 

If you get the same spec Ford injectors it wont be too much fuel, from what I have read the Ford injectors have multiple holes to squirt the fuel through where the stock ones have one hole.
Ever had an adjustable shower head? They have a solid stream and a fine mist (among other settings). Imagine the solid stream squirting into yoour engine, it's hard to atomize (mix with air) when it is in a stream. Now if you have the fine mist setting it mixes with air real easy.. this is what you want to happen in your engine as well.
I have never pulled either injector to look at it, the article i read did have a picture. I will try to find it.

Edit: Ok found it..the article is more for the earlier (Renix) era injectors that were prone to leak.

Article:
http://www.jpmagazine.com/techarticl...res/index.html

Picture:

 

i have found a few articles that say stock HO's should use 19lb ford injectors. 24lb for the Modded XJ'S You must also pay attention to the pentle of the injector...if you dont see the 4 holes dont get em....

 

I spent the other day reading and researching the injectors like crazy... there are all kinds of vehicles from BMW to Camero to ford vans and mustangs... just find the ones with the peach or pinkish tops... there the 19psi injectors that youll want to run in yours... the blue 22.5psi injectors get ran in the H.O. motors in 96 and above... theres another one that 25psi and there ran in the storked or charged 4.0's sometimes... you want to stay with the same psi injectors that you have... its not the psi of the injectors that give the horsepower or the fuel milage... its the "atomization" of the spray... these other injectors run several more holes then your 4.0 injectors which i believe run only one hole... Same reason on built diesels you can replace just the tips for added HP... except on these you have to swap the whole injector... goodluck with it man! also if you look fast theres i think 3 intake manifolds on ebay right now for what your looking for... and for the throttle body i cant remember the name but if you do a search im sure he will come up... i found him when i was researching boring my own throttle body... youll see a pic of abunch of different throttle bodies powdercoated and thats the guy you want to talk to... think they were only $90 and you dont have to pay a core as long as you eventually send him yours... i think anyway... but i saw him on SEVERAL sites and nothing but good things said! goodluck man!

 

Ebay--
But you need to remember that the OP (Sluggy) is from England.
Might not be a "good" deal after the shipping and such.

 

I did this swap...

intake is mid 1999 on up.

I guess you can put the spacer on...it's worthless, but you have it so you may as well. 62mm on throttle body. you bore the TB under the midplate, not over it. the newer manifold is already bored to 62mm.

 

and for the throttle body i cant remember the name but if you do a search im sure he will come up... i found him when i was researching boring my own throttle body... youll see a pic of abunch of different throttle bodies powdercoated and thats the guy you want to talk to... think they were only $90 and you dont have to pay a core as long as you eventually send him yours... i think anyway... but i saw him on SEVERAL sites and nothing but good things said! goodluck man!

Here is the link to him....

http://cgi.ebay.com/ebaymotors/_Car-...1%7C240%3A1318

 

thanks for the info friends, at least i now have an idea of where to start looking.

all this is in aid of just a few more bhp, dont need loads just a little bit lol