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Yet another... Build thread for an xj on 40s and one tons in norcal

Very very tuned ecu by flyin ryan.
So, from recent discussion about tires/gearing and such, 5.38 are not really meant for 40's. So, regearing or going to a smaller size tire are going to be your best options.
Probably not what you wanted to hear, but from e drivability stand point makes sense.
 
Yeah 7.17s would be nice
 
A nice 5.3L sounds like the answer

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I think the 5.3 would have been cheaper. After its all done with tuning etc im into it the motor for just under 6k...
 
I think the 5.3 would have been cheaper. After its all done with tuning etc im into it the motor for just under 6k...
In my state a good 5.3L is like $400 it probably would be for a trail rig well under 3k to have a well behaved 5.3

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Whatever rpms it can hold ...
 
I should have bought a 4.7 wj for 2500 and swapped my runnig gear over instead haha. Of course mine is already done and caged , etc.
 
Maybe try 7.17 gears? Or the 6.something gears and see? But then again if that isn't enough, going to another motor that's more powerful would make those almost over geared


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I think the 5.3 would have been cheaper. After its all done with tuning etc im into it the motor for just under 6k...

wow! 6.0 lq4 or a 5.3 for sure. too bad there would be smog difficulties as the exhaust needs to be routed exactly the same as it comes in the truck the motor came from. bummer man

Maybe try 7.17 gears? Or the 6.something gears and see? But then again if that isn't enough, going to another motor that's more powerful would make those almost over geared

14b maxes out at 5.38
 
I think a 37" tire and slightly lower lift would dial me in. I just wont be spending any money on this rig for quite some time, so it will stay as is for the foreseeable future. unless some 37s MTRs or pro comp MT2s on 8 lug rims fall in my lap.
 
wow! 6.0 lq4 or a 5.3 for sure. too bad there would be smog difficulties as the exhaust needs to be routed exactly the same as it comes in the truck the motor came from. bummer man

De-finely do-able! But yes...a PITA.
 
Had a great time at Sierra Fest.

The jeep was pretty gutless going up the long steep grades on highway 4 . Ive had Jes and Spencer ride in it recently and both feel like its nowhere near where it should be for a 4.6 stroker with a tricked out head. Was not as bad going up highway 80, but still full throttle most of the time to get up hills and still seeming gutless , I expected it to be more like 1/2 throttle needed with this motor...

Spencer mentioned that since my speedo is off the trans is shifting early and locking up the TC early, so I ordered a 41 (5.38s and 37s) tooth speedo gear from Quadratec to see if that helps as well.


Next is to check the cam lift with the valve cover off and scan the motor with Spencers Snap on Scanner to see if anything is acting weird.


I need to do some exhaust work - what mufflers are you guys running ? my downpipe is crushed way worse than normal at the neck - I am looking at a new walker downpipe since its like 55$ shipped and maybe a Magnaflow or Spintech muffler

I was 1.5 qts low on trans fluid and I added my K&N intake tube back on seemed to help somewhat for sure.

Plan is to swap fuel filter, o2 sensors, intake sensor, coolant sensor, and maybe fuel pump as well. I do have a weird noise coming from the fuel tank almost as if something is floating around in there. I wonder if the pickup assembly came loose ?

Fuel pressure tested ok , but I want to keep testing it.
 
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I took my downpipe off and heated it glowing red and removed the factory crushed section. Used a punch from header inlet and pushed it out.. seemed to work fine.
Maybe your cam timing is off. Sometime aftermarket stuff you need to degree the cams and check and recheck. I would do a compression check too. Maybe wrong pistons for the rods installed. That would make it like 7-7.5 to 1 compression instead of 9-9.5 to 1. That would be big difference.
Did your brakes feel better driving home after finding the pinched SS brake line?
 
ya. We gotta meet at a local brewery so I can convince you to go 5.3 swap. Your XJ is way to bad-ass to be running the 4.0. I know all the ins and outs of making it CA legal and would love to help you with this swap.
 
Brakes were ok but I still need to swap a new line.

Ill check cam timing twinhauler.

I will try to heat the downpipe and open it up first that way then.
 
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How do I degree the cam John?
 
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