First Stage of Modifications

[wizzo]

Hey guys,

First post, im new here

I drive a 2006 Jeep TJ, and im done with all suspension work and its time to get some power our of this 4.0, my driving is all in the desert here in Dubai, United Arab Emirates, alot of big dunes.. My plan for the car is a stroker, however i wanted your opinion on what i want to call my first round of mods..

They will consists of;

-Headers+Catback
-Intake
-Unichip
-Cam
-Maybe Port and Polish the head

I was also thinking to deck the head to achieve higher compression, but decided that i could just achieve that when i do pistons in round 2.. One thing i want you guys to take into consideration is that i currently run 91octane daily, and 93 octane is available and easy to come by for when i stroke.. I want to run compression a little on the high side, maybe 10:1 when i complete the stroker but im not sure what i can do and cant do..

Also i would like advice on which Cam shaft to use, id like something a little aggressive that would add power all over the power band, but top end is also important for me for the big climbs Would a port and polish for the head be worth it? I want to have the head completed.

[Cheromaniac]

Consider a cold air intake, 62mm bored throttle body, header, and exhaust as first stage mods 'cause you can do those without going into the engine.
Porting the head and swapping a cam should be considered as second stage mods and are best done when you're going to tear down the engine anyway to build a 4.6L stroker. I think this stroker recipe will come closest to suiting your needs:

4.6L low-buck stroker

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Keith Black UEM-IC944-030 pistons
9.8:1 CR
CompCams 68-235-4 210/218 degree camshaft
Ported HO 1.91"/1.50" cylinder head
Mill block deck 0.030"
Mopar/Victor 0.043" head gasket
0.040" quench height
'99-'00 Chevy LS1 26.2lb/hr injectors for '05-'06 engines
270hp @ 5000rpm, 324lbft @ 3700rpm

You'll need to have the engine dyno tuned and that's where the Unichip will be very handy.
BTW, I live just 85 miles South from you in Al Ain.

[wizzo]

Thanks for all the info The part list looks great, i like the cam too..

My only question is what are my other piston choices, and i was thinking of a little more compression maybe 10-10.5? Maybe 9.8 is enough the car might see a 50 shot in the future..

[Retlaw01XJ]

KB offers a higher compression piston as well.....IC945. About $400.
Another choice would be pistons from Bulltear, custom made, about $429.
http://www.bulltear.com/catalog/product ... cts_id=242

[Cheromaniac]

KB offers a higher compression piston as well.....IC945. About $400.

Those will push the compression up to ~10.9:1 which is too high for 93 octane pump gas. They'd be good for an engine running on propane or liquid natural gas.
If you want a higher compression than 9.8:1, you could have the head shaved instead but I'd advise against going higher with the compression because in a country where it's over 100*F for at least 7 months/year, detonation is going to be an ever-present threat.

[wizzo]

Thats a great point chrom, i think ill just stick to the 9.8 that may be a little more nitrous friendly also.. No? Maybe a 50shot for when we are playing on a big dune for the big climbs and racing in the sand..

[wizzo]

Also was wondering is the head on my 06 TJ the HO head? And i have the correct rods correct? unless 4.0 rods vary?

[Cheromaniac]

Also was wondering is the head on my 06 TJ the HO head? And i have the correct rods correct? unless 4.0 rods vary?

Yes, it's a HO head with casting no. 0331.
The rods didn't change during the 20-year production run of the 4.0L engine so yours are fine.
A 50 shot of N2O should be OK but you might need to upgrade the fuel pump.

[SilverXJ]

The rods didn't change during the 20-year production run of the 4.0L engine so yours are fine.

Actually, they did. See http://www.jeepstrokers.com/forum/viewt ... ?f=34&t=53 Bottom post shows some pics.

[wizzo]

Alright, this week i will have the headers fabricated along with the exhaust, im thinking 2.5 inch, or should i go for a 3 inch exhaust? Also what size runners do you guys suggest?

I read that i can just port my stock throttle body post butterfly, and that would make it around 60mm, would that be alright, or am i better of finding a 62mm throttlebody?

After the boltons are done, i will be going to get it tuned on the unichip q+..

After that i will do the head with the comp 235 cam and valvetrain.. Chromo which machine shop do you use? I want to get the head port and polished.. I plan on the block in a few months time even if that way it will cost a little more in labour..

What components do i need to order for the head other than the Comp Cam, does anyone have links? I believe its best to go with the Mopar valvetrain?

[Cheromaniac]

Actually, they did. See http://www.jeepstrokers.com/forum/viewt ... ?f=34&t=53 Bottom post shows some pics.

Interesting. It probably wouldn't matter which casting you used as long as all six are the same.

[wizzo]

Chromo!