99+ intake upgrade recipe

[pma4x4]

I would like to make sure i have this parts list correct. If i am missing anything, could some one point it out?

1996 XJ 4.0

installing and/or using following items
'99+ 4.0 intake manifold
new Edelbrock Header '91-'99 #65923
'99+ PS bracket and tensioner pulley
New fuel injectors from Precision auto injectors '96-'98
'96 original fuel rail
'96 Bored TB from the fastman
manifold/header gasket for '96 4.0

Exhaust is done. I will just have to get a new down pipe after this. Also a cold air intake is in plans during this project.

I know there is the possibility of plumbing of vacum lines and lengthening of sensor wires. I am wondering if i got it all right here

[CanMan]

PS bracket and pump is the same for 96 and later.

Otherwise, you need to extend the wires for one of the sensors, the intake air temp sensor IIRC, and move some vacuum lines.

[hubs97xj]

Might as well throw new hardware for the manifolds on there too.

[pma4x4]

Might as well throw new hardware for the manifolds on there too.

I am in AZ, no rust down here. so i think the hardware is good. unless your thinking just stretched.

[hubs97xj]

Mine were in good shape, going by appearances, but I'd read on here that they should be replaced, so I went for it- another $15 for hardware and spares seemed like cheap insurance. I don't know if it's necessary, but that's what I did.

[pma4x4]

Makes sense. Thanks

[REDXJ4FUN]

I didn't have to exten the wires i just moved the sensor

[userbmx1315]

so is it just 'bolt on' and go? all i have is the intake. no brackets or anthing. (except on my 98 when i swap the stroker)

[pma4x4]

From what Canman says and i have found it in the last few days, if you have a late '96 or newer PS bracket then yes it is a bolt on. like said before you may have to extend vacum lines and or some wires but some have and some have not so you wont know till you do it.

My header is in, still waiting on Injectors. I won the auction for the 99+ intake so that should be here middle of next week. and the TB from Fastman i may have on Saturday. Airflow Snorkel should be in late next week as it had to come direct from Australia.

Exhaust shops says they might be able to get 2.25 pipe up for a down pipe but at least i wont have that stupid clearance dent in it anymore.


I am taking pics, I may do a write up. Of course i have threatened people with write ups before.

[pma4x4]

Now this thing is on hold for another week as the guy i won the auction from for the intake just shipped it slow boat brown truck when the auction stated Priority mail. I was just reminded why i dont do ebay no more.

[pma4x4]

I recieved the TB from fastman. I posted some pic to show the quality work and difference.

Pics are here
http://www.arbrtek.net/xtek/fastmans.html

[pma4x4]

Well, the upgrade is done. for a 96 and newer it is just a 99+ intake, and gasket. I moved the IAT sensor to the port just behind the TB. There is not much slack left in the wire but it still fit with no mods.

Pics are here.
http://www.arbrtek.net/xtek/airfueltek.html

[Dr. Dyno]

Nice job. I hope I can get my '01 XJ intake/PS pump/PS bracket with idler pulley on in the next couple of weeks. Not easy when you have a busy work schedule and you have another project going (1995 Mustang GT).

[pma4x4]

Went and di the test drive and gained power across the entire band but more so in higher Rs. Gas mileage is up +2. So all in all it turned out. I can actually bark my tires if I really want to.

[dakineJ]

Nice,good thread,thanks.What tranny,gearing,and tire size are you running?

[98 jeepjeep]

you should have upgraded the injectors to the Bosch ford style 19lbr's.....I have a set if ur interested.

[pma4x4]

Nice,good thread,thanks.What tranny,gearing,and tire size are you running?

Sorry, for the delay in response. Just got back from our annual AZXJ run.

AW4
3.54s
31 BFG ATs

[dakineJ]

Sorry, for the delay in response. Just got back from our annual AZXJ run.

AW4
3.54s
31 BFG ATs

Good to know,thanks

[pma4x4]

you should have upgraded the injectors to the Bosch ford style 19lbr's.....I have a set if ur interested.

Thanks for the offer but I went with a rebuilt set from Precision Auto. They are ford injectors running at around 24lbs.

[pma4x4]

This is been a excellent upgrade for me. I built it for more top end power for highway use as my wife and do a lot of overlanding. The end result was power through out the entire RPM range, crisper throttle response, smoother idle, easier starting and 2+ mpg gain.

[pma4x4]

end results

99+ 4.0 intake manifold
new Edelbrock Header '91-'99 #65923
Used gasket that came with header
New fuel injectors from Precision auto injectors '96-'98
'96 original fuel rail
'96 Bored TB from the fastman
Smooth bore 62mm TB spacer
Gibson Airflow snorkel
Felpro TB base gaskets
Down pipe is 2.25 to 2.5 from a foot in front of the cat all the way back.
Magnaflow hi flow 2.5" universal cat
Series 40 Flowmaster.

[jeep pox]

Hey so after 6 months of running this how is it working out? I just picked up a '99 intake and am considering doing this to my '97. Might to a port and polish too... idk..

[CanMan]

I never noticed a difference in power or mileage. If I wasnt swapping engines and needed to pull the intake/exhaust anyways, I wouldnt of bothered swapping it on. .02

[MoparManiac]

I changed mine out a while back when I put in an APN header, so hard to tell exactly how it affected the driveability/mileage.

There is no real power gain, though it seems like the torque band gets smoothed out. With the older style intake, it was like a turbo button was pushed at 3k rpms. Now, the torque is smooth from idle to redline.

[pma4x4]

Ok here are my results.

99+ 4.0 intake manifold
new Edelbrock Header '91-'99 #65923
Used gasket that came with header
New fuel injectors from Precision auto injectors '96-'98
'96 original fuel rail
'96 Bored TB from the fastman
Smooth bore 62mm TB spacer
Gibson Airflow snorkel
Felpro TB base gaskets
Down pipe is 2.25 to 2.5 from a foot in front of the cat all the way back.
Magnaflow hi flow 2.5" universal cat
Series 40 2.5" Flowmaster.


With the parts listed above i gained the following.

quicker starts
much quicker throttle response and RPM climb.
More power at bottom end and up thru about 3000 RPMs
gained back 2" of vacum at cruise.
no where near as much trouble climbing the hills on 87 to payson and back.
2 mpg gain avg.

Jeep is a 96 XJ 4.0 OBDII, 231 TC, 8.25R D30F,AW4 rebuilt about 15K miles ago with shift kit. and the mileage currently on the XJ is 148,xxx

I am still running 3.54s with 31s and a bunch of extra weight ie roof rack bumpers winch gear in back and 3/16" skids.

On a side note I was never able to sqwauk my tires in reverse on pavement... EVER. now I can no prloblem.

The whole idea of this project was to gain power in top end for cruise but i gained all around.

I hope this info helps you out.

[pma4x4]

I cant remember if i linked these pages or not so here they are...again?

http://www.arbrtek.net/xtek/airfueltek.html

http://www.arbrtek.net/xtek/fastmans.html

[jeep pox]

I saw all that Rob I was more wanting to know if you think it was worth it or not?

[J Money]

I just did the following a few months back...

Heddman Header
99+ Intake Manifold
Flow Master
Electric Fan
AFE Stage II Intake

I noticed the same thing. More power accross the entire power band and +2 mpg. It wasn't a cheap round of upgrades, but it made my driving experience much better. Now my Jeep doesn't have to downshift going over some grades around here. If anything, I don't feel as if I'm beating up my XJ as bad.

[pma4x4]

I saw all that Rob I was more wanting to know if you think it was worth it or not?


Sorry.

Short answer.... YES.

A lot of the obstacles i had to fight with for power in Payson were much easier and less throttle to get over them.

The purpose was to gain top end. I ended up gaining the entire range so for me it was very well worth it.

[jeep pox]

sweet! thats what i needed to know. Thanks

[pma4x4]

No problem,

I imaging this thing should be pretty narly off the line once i regear. It already wants to snap necks.

[coldforge]

I cant wait to put my intake on i have been wanting to do this for years never had the money. But i now have one sitting at home waiting for me to put her on :yelclap:. I paid lil high but its competle with everything even an extra T.B. Might be my test TB for boring. So i guess that leaves alot of extra crap to :(

[coldforge]

Thanks for the offer but I went with a rebuilt set from Precision Auto. They are ford injectors running at around 24lbs.

WOW!! and that doesn't run to rich with just the intake?

[pma4x4]

WOW!! and that doesn't run to rich with just the intake?

24 lbs is nominal for the 96 year.

[Tim Dog]

I got 2000 intake I'm waiting to drop in my 98 XJ. I've had it a while. Just gotta get the injectors and Throttle Body. I have everything else done. The intake has been ported and polished inside and out. Looks like its chrome. I want to send it out to have it ceramic coated before installing to reduce temperatures. My header is coated. I think it would be a good upgrade for the intake too be they sit on top of one another

[coldforge]

I got 2000 intake I'm waiting to drop in my 98 XJ. I've had it a while. Just gotta get the injectors and Throttle Body. I have everything else done. The intake has been ported and polished inside and out. Looks like its chrome. I want to send it out to have it ceramic coated before installing to reduce temperatures. My header is coated. I think it would be a good upgrade for the intake too be they sit on top of one another


How much did the port and polish cost you? I bought some temp paint im going to put on mine and the air intake hose. I do have an extra TB BUT im over in the sandbox sorry. O Yeah was there an gains with the PandP job?:read:

[Tim Dog]

How much did the port and polish cost you? I bought some temp paint im going to put on mine and the air intake hose. I do have an extra TB BUT im over in the sandbox sorry. O Yeah was there an gains with the PandP job?:read:

I actually found it on ebay already done. I think I got it for $80. It's been a while. There is one spot I have to have repaired. The guy did a lot of porting you can say. He did a quick fix with some JB Weld on the bottom. I'll just grind it and weld some aluminum back in there. This thing has a mirror finish.

[Dr. Dyno]

I did an '01 XJ intake swap a few months back on my 9.25 compression, stock cam 4.6L "poor man's" stroker and ran my Jeep on the dyno (AX15, stock 27.4" tires, stock 3.07's) to compare the result to my old '92 intake:

Before: 200rwhp @ 4750rpm, 254rwtq @ 3500rpm
After: 202rwhp @ 4700rpm, 258rwtq @ 3400rpm

The torque gain was up to 5lbft from 1500rpm to 4800rpm, throttle response was improved, fuel economy was improved by ~1mpg, and I can run 87 octane. The newer intake made the engine run slightly lean so I raised the MAP voltage from 5.1v to 5.2v to correct it before running on the dyno. Everything else remained the same.

[xjwest]

jpmag claimed they lost 5 hp after this swapping to the new 99+ intake.....