Performance mods I'm looking into

Ok, just a few things, probalby the absolute extent of my performance Mods for my 99 XJ.


1)K&N FIPK2 (already have and installed...love it)

2)Gibson -or- Dynomax catback (not sure what to go with, don't want
anything too loud, but also want performance out of it...opoinions/ideas??)

3)Rock-It hi-Flow Throttle Body (This brand isn't a must, just the only one I know of ...from Quadratec anyothers out there ...better cheaper??)

4)Firepower Ignition Kit (cap, rotor, wires, and Screamin' Deamon coil...also from Quadratec) w/Bosch Plugs.

5)Jet Chip (stage 1?? or 2??)

This is still going to be my daily driver, and I am pretty light with my right foot, but I do have my moments when its heal to the steel, but don't we all? I still want tolerable fuel economy for daily usage. I asume with adding a chip of any kind I'm going to be forced to run at least 91 Octane, so would tuning with the hypertech tuner be a better idea?

Thats pretty much all I had in mind for performance... The only other mods were changing shocks to Edelbrock IAS (heard they're nice for street driven vehicles), Optima Battery, and MAYBE not sure yet a Budget Boost.

Any other ideas/opinions? Let me have it, check out my page...on cardomain

http://www.cardomain.com/memberpage/680128

a stage 1 jet chip is for stock vehicles. stage 2 is for vehicles with an exhaust, intake, and 180* thermostat. ive looked into these a lot before and IMO i figure that they arent worth it because you have to run premium gas and its not worth paying the extra money every time you fill up. i would look into a header for your jeep. i got a gibson header at i like it, borla is a good one too. i would stick to the basics, intake, throttle body, header, exhaust, maybe even a high flow cat, plug wires, plugs, and ignion. does your 99 have the new intake manifold or the older style one?

I had the dynomax cat-back and hated it. It was as quiet as staock except at on ecertain rpm which was very annoying... I have the flowmaster super 40 now and love it. As far as ignition goes, I'm looking into this http://www.performancedistributors.com/amcdui.htm -still need to ask dr dyno if that one will work though. Ive heard mixed reviews on jet chips- money better spent somewhere else if you ask me.

That distributor is designed for the 232 and 258 I6's, not the 4.0. The 4.0 already has an excellent distributor with a magnetic pick-up so why change it? The stock ignition coil is also an excellent piece that doesn't need to be changed. Just about the only ignition component that I would change are the plug wires; Magnecor 8.5mm wires are probably the best, though I do like my own 8mm Splitfires (118k miles old and still performing flawlessly) with their heavy duty plug boots. The stock Champion copper core plugs are very difficult to improve on so these are what I use.
As far as the JET chip goes, your $300 is better spent elsewhere. If you have OBD II, the Hypertech Power Programmer III costs only $50 and is probably much better, but that requires the engine to remain virtually stock just like the JET Stage 1.
I'd list cheap performance mods that work well on the 4.0 as follows:

1. FIPK. Why spend ~$250 on K&N's? Just buy Rusty's intake with the 6"x9" K&N cone filter and build your own heatshield around it. That'll save you $150-200.

2. Bored TB. The Jeepersn'Creepers 60mm TB is adequate for a 4.0, and spending an extra $100 for a 62mm TB will gain almost nothing in performance.

3. Rusty's high-flow cat & Flowmaster cat-back. Great value, and the Flowmaster muffler is as solid as a brick shed.

4. Mandrel-bent 2.25" downpipe. Ask your local muffler shop to make you one, and throw the crushed restrictive stock pipe onto a junkpile.

5. Clutch fan to electric fan conversion. Yes, the 5lb clutch fan is a useless piece of garbage that's sucking HP and mpg from your engine. Get rid of it and go dual electric. A ~$50 slimline high performance electric fan from e-bay mounted to the stock fan shroud will give you better cooling and not rob you of precious HP/mpg.
_________________________________
Dino's "Mean Green Machine"
1992 XJ Laredo 4-dr - 4.6L I6 HO Stroker - 179k miles - AX15, NP231, D35c, D30

258hp@4800/320lbft@3200, 1/4 mile = [email protected], 0-60 = 5.9secs
Websites - Jeep 4.0 Performance, 4.6L Stroker Build-Up, Dino's Jeep Tricks

Dr. Dyno...

well that sure shed some light on matters for me...at least with the ignition system. A little too late for me to NOT do the FIPK, as I already have it. I'm not knocking Rustys, or any of the "homebrew" style intakes, but they're just not clean enough for me. I know THE FIPK is alot more pricey compared to Rustys or most others on the market, but I don't really have the means to go fabbing anything for a heat shield and come up with the same results as something premade.

Got a site on where I can read more, price and maybe purchace that 60mm TB?

I'll have to check out Rusty's site again for exhaust set ups...I really don't want to go with a flowmaster....a little too loud for my liking on my Jeep( have a 40series on my other ride). I want performance with little change in exhaust sound, if at all possible. OR if it changes sound, something that's tolerable.

Dothedew,How did the Dynomax perform for you aside from the annoying sound you didn't like?

Dr. Dyno said:

the Hypertech Power Programmer III costs only $50

Click to expand...

$350.

Wolf said:

$350.

Click to expand...

Oops, I made a typo. I meant the Hypertech is $50 more expensive than the JET chip.

http://www.thefastman.com/Throttlebodies40.asp
I had the jeepersandcreepers tb on my 95', this time around on my 00' i used a FastMan throttlebody...not much more expensive, and it seemed to me to be a better product.

Pretty much all the stuff in my sig. I like. I REALLY like my exhaust, it's pretty quiet compared to my old flowmaster series 40 deltaflow, but it sounds much better and doesn';t have the same extremely annoying resonances that my flowmaster did... my parents like my new exhaust much better also...lol I'm going to update the link so you can hear my exhaust.
here: http://us.f2.yahoofs.com/bc/417fb9d7_289c/bc/Audio+Clips/2000+Jeep+XJ+Exhaust+Long-Loud.wav?CCuawxBBGk2Y2e.C

Jeepin, Holy ish... Exhaust sounds real mean. I like it ALOT. What is it like at high way speeds (55-70 mph) inside?...How about at just normal driving around town? Also, where'd you pick the Banks Muffler (any part number?) up at?


Hmm I guess I revised my wish list (Keeping inmind I already have the intake)...Just upgrade the exhaust...still not totaly sure yet on what I want...(Exhaust can often make or break the vehicle.. too loud and no go is rediculous) and maybe Upgrade the TB. Screw getting stuck with 91 and higher octane gas with a chipped vehicle,and if you say the stock ignition parts are pretty good then I'll take your word for it.

i found that no muffler was perfect for me. most people think its too loud but its not that loud it just echos a ways. i think it gives a nice deep tone. i also didnt loose much torque at all and what i did notice i gained back when i put my intake on. as far as having "no power" like everyone says, ive had my fair share of stupidity with getting into some small little races with people and ive held my own. those days are long behind me now but i have plenty of power and i love the sound.

Slammed_am said:

Jeepin, Holy ish... Exhaust sounds real mean. I like it ALOT. What is it like at high way speeds (55-70 mph) inside?...How about at just normal driving around town? Also, where'd you pick the Banks Muffler (any part number?) up at?

Click to expand...

Thanks... I really like it also! Highway speeds I can barely hear it with my radio at normal levels, around town i love getting on it and putting it under load to hear it really sound good. I ordered it straight from banks(Monster Muffler from the "stinger" package) along with my header. The only other thing is that my jeep has been EXTENSIVELY sound deadened, so that will play a part in the cabin noise. But it is much quieter than my flowmaster... i didn't like driving my g/f home at night because i would wake up the neighbors... she was the last house on a dead end... this one i can drive up, let it idle... it's really quiet at idle, but with a very clean sound as you heard. good luck- Chad

That does sound good. I think my Flow Master 40 sounds about the same though. maby just might be a tad higher piched. When It was put on, it was registering right around 100db's at 1500 rpm if I remember correctly. Although it has melowed out alot sence then. If it wasn't 20* out, and 10:00 at night I would run a db check on it now. But im guessing it's down around 90db or so now. It is louder when it is cold but as soon as it gets warmed up it isn't so bad. It's farly quiet with windows up at all speeds, but if they are down it can be a little anoyngly loud at certain speeds.

From what I have heard, the super 40 does sound better than the 40 delta that I had... the delta was kinda annoying, and it cut out and got hollow at around 4400 rpm. I meant to point that out earlier that i had a different muffler from what you have now.

I second the fastman throttle body. Very good quality work and support from a one-man shop. I have the FIPK II combined with the fastman TB and it made a noticeable difference to my driving ( one gear higher when climbing hills - no need to downshift as often).

three words....borla......stainless.......throaty.......expensive...i guess that was four words

I've got the Dynomax as well. I love the sound of it. For the most part it's only a little louder than my stock muffler, it only gets substantialy louder when the engine is held in the mid rpm range. The best thing about the sound is how low its tone is. Performance wise, I don't have any stats, but I did gain enough power to feel the difference and my my gas mileage greatly improved. It got even better once I put on my Banks headers.

I just put on a flowmaster 50 series (delta) from Rusty's last night. It came with the mandrel bent 2.5" pipe all for $150. Shipped to my door in two days. I was worried that it might be too loud, that's why I went with the 50 series instead of the 40. In the jeep you can tell that you have a louder exhaust when you first take off...it's much deeper...like a v8. But at normal driving speeds it's really not noticeable from inside the jeep. Outside it sounds sweet. At first I didn't really notice a difference in the power, but since I reset my computer there is a pretty noticeable difference, especially in the upper rpms where it used to seem to die off...now it pulls harder and harder. I like it. Next step...bored TB and 62mm spacer. Oh and P.S. ....I love beating ricers off the line. They sometimes catch up around 60 mph due to the garage door like aerodynamics...but that's okay.

oh...I might be going to the dragstrip tonight. I want to get some early #'s to compare to so that I can see if my mods are doing any good. My goal is to beat Dr.Dyno's awesome 14.5 1/4 mile and 5.8 0-60 time. That's real quick for an suv. Nice job by the way, Doctor.

kmagnuss_2000 said:

oh...I might be going to the dragstrip tonight. I want to get some early #'s to compare to so that I can see if my mods are doing any good. My goal is to beat Dr.Dyno's awesome 14.5 1/4 mile and 5.8 0-60 time. That's real quick for an suv. Nice job by the way, Doctor.

Click to expand...

Thanks. You'll either need a stroker, supercharger, or nitrous to beat me and I don't think I'll be sitting around at 14.5 for too long either.
I'm looking for some stickier tires to improve my woeful traction and I have plenty of weight to shave off (spare wheel, rear seats, less gas) before I do my next run, so expect low 14's pretty soon.
_____________________________________
Dino's "Mean Green Machine"
1992 XJ Laredo 4-dr - 4.6L I6 HO Stroker - 180k miles - AX15, NP231, D35c, D30

263hp@4900/321lbft@3300-3800, 1/4 mile = [email protected], 0-60 = 5.8secs
Websites - Jeep 4.0 Performance, 4.6L Stroker Build-Up, Dino's Jeep Tricks

I think high 13's is totally possible in the xj. I plan on the same progression as you...bolt ons, then port/polish, then stroker. BUT...if I still feel the need, and I haven't driven into a tree yet, there's a small chance of a t3/t4 turbo. Small chance. 300 hp and 400 ft/lbs at the wheels would be nice...but it's all just a pipe dream right now. Baby steps...and I'll just keep learning from your trials and errors. Thanks again Doc.

Oh, and sorry for hijacking your thread.