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98xj 5.3 swap (the poverty method).

I was thinking about underhood pressures this morning and this thread came to mind. Are you still running that scoop? If you are, try blocking it off and going for another highway drive. Increasing pressure behind the radiator definitely isnt helping airflow through the radiator.

IMG_20150411_180924.jpg
 
I was thinking about underhood pressures this morning and this thread came to mind. Are you still running that scoop? If you are, try blocking it off and going for another highway drive. Increasing pressure behind the radiator definitely isnt helping airflow through the radiator.

I was thinking the same thing (I think someone else pointed it out already), BUT I thought of a problem with that. It would make sense when driving down the highway, but wouldn't explain the overheating while wheeling (ie; slow climbs up the mountain on a relatively cool day).

I did make some more room in front of the rad, and unfortunately, I think it may have helped. Moved that winch control box and put the license plate vertical, and moved the trans cooler closer to the main rad and went out again. Now on the highway, +25C out, I can JUST stay under 94 without the fan coming on, at a cruise on relatively flat ground. Wheeling I'm still warming up a bit, but I think last time we were out it was pretty warm and I made it to the top of the mountain (all boulders all the way) and I didn't break 110C. Still not great at all, but it's definitely better.

I also feel like my upper hose has less pressure every time I take it out, suggesting that there is still air in the system that's slowly working itself out.

I'm goona give up on this issue for a bit and just assume it'll fix itself, or I'm just an idiot and need more air flow.

Actually, I'm going to try blocking off the scoop just in case as well. I'd feel way too dumb if I didn't, and figured out it was the problem years (and several rads) later. :p
 
Yeah blocking if you can just tack a few sheets on would be a quick easy way to test it. I think the wheeling heat is caused by the fan. I think you had said it was 1600 CFM, which is not enough. I would say you should consider adapting a taurus fan to it. Also, if the shroud has a lot of blocked off area, you can add flappers to the shroud which allows air to pass more easily through at speed, but will close down and work like a normal shroud when moving slowly.
 
Yeah blocking if you can just tack a few sheets on would be a quick easy way to test it. I think the wheeling heat is caused by the fan. I think you had said it was 1600 CFM, which is not enough. I would say you should consider adapting a taurus fan to it. Also, if the shroud has a lot of blocked off area, you can add flappers to the shroud which allows air to pass more easily through at speed, but will close down and work like a normal shroud when moving slowly.

Yea, I've actually got a cut up taurus fan on the shelf, but it may not be easily adaptable due to how I cut it up for the 4.0L rad. We'll see. You may be right.
The shroud does have flappers, though I think it should have more, which I may add myself. Just hate messing with a $1000 radiator :) This is why I don't buy new stuff. Always worried about breaking it. I like my junk to be junk enough that I never have to worry.

On a positive note, I'm feeling pretty confident about the reliability of my Jeep now. Only a few issues I need to iron out.

* Front frame keeps bending/twisting somewhere, causing my alignment to go out. I already plated the driver side, but I think I need to plate it all the way to the stiffeners, and build a new brace to the passenger side. Only have an issue when I do real angry climbs.
* Front suspension still makes noise and I'm losing my mind trying to track it down. Noise I can deal with. Not knowing the source of the noise worries me :).
* Still no oil pressure gauge and no one seems to know anything about the stock sender. The 5.3 has an oil pressure sensor on the top back of the block which runs to the ECU, but I have no idea if the ECU sends that data via Mode6 or not. Some guys say it does and say they got it working, but i've never got any data from it using any of the PID's I've found. I have an analog gauge (but need to find a sender), but I really hate having to install ONE gauge when everything else is available via OBD. Last wheelin' trip got me paranoid though as my buddies truck lost OP during a big climb and stalled. Lost brakes and nearly rolled off the mountain. He's got a manual trans though, so didn't die. I however, will die cause auto. Fuuuu.
 
Whoops. Forgot a hose clamp on the transmission oil outlet. Blew out on the road. Never smelled burning trans fluid before, so at first we thought we'd just driven past an Indian's house. No one else in the truck could quite place the smell either until we noticed the smoke behind us. Some helpful rednecks showed up just as I'd got it fixed, and brought me some trans fluid. Needless to say, I got home and "upgraded" to more hose clamps.
UPGRADEZ!

Made some progress under the hood yesterday.
As my upper coolant hose was just a stock xj hose massaged into place, I didn't have room to put the intake to passenger, where it ultimately has to go because I want it routed into the cowl like before (I've already hydrolocked it), and the plan was to stick the ECU in the drivers cowl, thus no room for a 4" intake tube. So last night I decided to get this all done.

Here's the ECU in it's new home.
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jbE_CWE1ByasqrCUxVltE7QcHoX7O-V_wXvQ9Fmotai9=w1746-h1309-no

Fit's like a glove. Probably doesn't even need to be strapped in. Fits snug without binding, doesn't flop around.
Once I get the new cowl intake finished, I'll pull the harness to remove all the stuff I'm not using, and re-work it so the entire harness stays at the back of the engine bay. By the time I'm done, it should look like there's no wiring. I've put this off for too long.

And the new rad hose with the intake flipped over to passenger.
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The rad hose was a pain in the ass only because once again, I went to Lordco (useless), and like always, all the guys were busy fawning over the new girl working there (and they're useless even if she's not around). I normally only bother dealing with one guy there (the youngest), as he's the only one who doesn't surprise me that he's managed to survive into adulthood without getting himself eaten by a 3/4 retarded raccoon. He wasn't in, so I tried someone else. I brought some wire sheath formed to the shape I needed, asked the guy if he had anything close, he asks what vehicle it's for, I explain again that it's an XJ, but that it's a chevy 5.3 and completely not Jeep radiator. He, as always, insists he won't have anything that will fit, as is always the response I get from everyone but my one guy. Asked if they have any universal hoses, and he says "nope. No one makes anything like that. It's all OE application.".
Saw another guy there I'd never talked to before (probably the second youngest) and asked him. He says "oh, I'm sure we've got something. Come paruse the wall in the back." Turns out they have 700+ hoses in stock all nicely hung out on the wall. Looked through for a bit, found a few close matches and asked why they don't have any universal hoses. He says "what do you me? who told you that?" and brings me to the entire ****ing WALL of universal hoses and slip adapters. Fuuuuuu. Pointed out that the other guy had said there's no such thing, to which he responds, "was that the short portly guy? Yea, I'm frankly surprised that guy manages to put on his own pants every day.".
Turns out this guy, and the guy I normally deal with, are the manager and assistant manager. Good call Lordco boss. At least you have the right people in charge. Now just give them the authority to fire everyone else.
Seriously, if that was my business, I wouldn't even let most of their employees shop at my store, let alone put them behind the counter.

So, the Universal hose worked perfectly. Grabbed an 18"x1.5" and a 1.5-1.25" slip adapter. Fit perfectly and conformed just right to flip over my intake tube.
I also had to cut out some more of my hood for clearance on the passenger, so I came up with my final design for the scoop, which I'll hopefully have posted tonight.
 
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There we go. Scoop complete. Still undecided about the colour for the perforated sheet. May go blue to match other stuff. May not.

I decided a while ago, mainly due to lack of a tube bender, that I was going for a stealth look on this build. All hard lines, but soft edges. I think the new scoop fits the bill quite well.

Old Scoop
For reference, this was the first incarnation of the scoop. It was definitely just function over form as I needed the clearance for the motor.
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New Scoop!
Started like this:
sgVUbgExSCVz9SyjsQEMOfMoGhb_VTQRDVVfIcDhY437=w1746-h1309-no

WiQFiwmDEoSGn2aLshjbBXBOvXmC0RCzHsy9ygtOao3D=w1746-h1309-no

Cut out about 2" from the front, and about 5" on the wide end of the triangle. This gave me 4" overall height with 8" on the arc down.

Recycled my roomies Mustang hood.
0pUEOWTFDNp0PliRwpIRH56Om4uthA9wFPDjJQW1j8o-=w1746-h1309-no

mYWX3CGCDA4_NAXaxk41RgYSZip611jhkB90PUHICtM-=w1746-h1309-no


Took some shaky pictures of the bondo process. I should point out that like always, this is my first attempt at welding body work and trying to make it look ... not welded. I seriously considered just leaving it with the red mustang angles, and the raw tacks and just flat clear coating it, but I was bored and wanted to see if I was capable of doing a proper job of this (boorriiinngg).

And the almost finished result:
FEvFnK4XL0J0sR6xgJ6q_0C9HgjphoLjSR4wI-cU-S4j=w1746-h1309-no

sf0Nh6TE7JDbswKcMuRs_1ujYpM9tU7X3NBHU7ho0iy2=w1746-h1309-no

nlgT2K2jRpJD0TLPb6pBXDa9NDLv2A15VUT_n7ULMIFH=w1746-h1309-no

Wvbq7gltVciHMnzfixAczMjLH7pDzA-43zjJ1EPaypmj=w1746-h1309-no


For a first attempt at (somewhat clean) sheet and perforated welding, and bondo/paint, I think it went not too bad. Definitely could've used a bit more time with the orbital sander, as there are a few obvious scratches, but really, it's not like this hood won't get smucked by a tree by tomorrow, and I only wash it if I need to cross over the border.

The perforated stainless sheet SUCKS to weld. Shit just explodes on contact. If I ever do this again, or I decide to clean this up, I'll stick the perforated sheet inset under the sheet metal half an inch and weld it from the back.

Anyhow, that's my silly scoop. The scoops first incarnation turned a LOT of heads. At least once a week I find myself being followed home by scary hillbillies/yokels who offer to buy my junk. Everyone LOVED the old scoop for some reason. It was hacky for sure, but not like, the nice hacky.
 
Just thought I'd chime in here that I've got my OBA (on board air) working now as well. From the beginning, everything I read on the intarwebs said the stock pump wouldn't fit in the stock location, and I foolishly didn't bother to confirm. Turns out it fits just fine. With engine fully torqued, I've got over an inch between the pump body and the frame rail. Ya'lls crazy.
So, stock pump, cut off the ends of the stock hose adapters leaving about 3/4" of pipe sticking out. The adapters had to be installed AFTER the pump was in place.
Seems to work fine. Haven't load tested it yet on a tire, but it seems to be moving sufficient volume and it pressured up way beyond what I'd rated my system for because the pressure switch is apparently seized closed. Holds 200lbs just fine. Still leaking a bit from the compression fitting I stuck on the HP side, but that's entirely my inability to figure out compression fittings.

So, FYI to anyone planning the swap, 5.3 from an 05 fits just fine between the rails and motor, using the Novak mounts. Hell, I think I could still drop the motor another inch or two and it'd still fit.


That said, I believe I've got the newer pump in there now, and I've heard that the rear electrical connector controls some variable compression thing internally. Does anyone know about this, and if so, anyone know what that circuit is looking for to just max it right out?
 
WTF. EVERYTHING I read said not a chance :p.

At any rate, with the hood now mostly enclosed, I ran into another problem. While the radiator is definitely working better now that I've limited the ram-scoop effect, thus decreasing under-hood pressure and increasing radiator air-flow, the under-hood temperature has increased. Out wheeling yesterday, and Jeepy started producing a few new unusual odors. Figured out it was new-ish paint/bondo getting heated up. Hood was hot enough I couldn't hold my hand on it :). Derp.

So I'm going to have to open it up a bit more on the top. On the highway it's fine, but on the trail, without the massive amount of air-flow, the hood is just too restrictive. Going to cut out some triangles on the sides of the scoop, and/or on top and fill it in with more perforated sheet.

The new tune (from Diablew) changed the shift points, and on the street they're fantastic, but on the trail in 4L, they're way too harsh. There is no gentle shift from 1st to 2nd, which nearly ****ed me up a few times on mild climbs. Going to leave it for now to see if an adjustment in driving style can deal with it or not.

The new universal rad hose has a coil spring internally, but either it's not full length, or it slipped/shrunk, because now the hose is folding over just past the outlet. This didn't seem to have any negative effect on cooling, as the pressure fixes it when it warms up, and the motor never broke 99c (using the high speed trigger which I think is 96/91c).

The A/C pump worked awesome. Still need to figure out how to attach the high pressure side a little snugger though, as it blew out right as I finished filling up my 4th tire. Pumped awesome though. Filled all 4 35x12's from around 12psi to 30 in under 5 minutes. My buddy filled up his 33x10.5's and his gf's stockers about 10psi in about the same time, which puts me at slightly faster, despite idling at 500RPM vs his 1000, so I'm pretty happy thus far. We'll see if this pump holds up, and I'm still trying to figure out if the variable vane is by default, at only 60% output (I suspect it is from what I've read).
 
So I beat the hell outta the Jeep last Saturday, and broke a few things.
Lots of moderate difficulty, high speed trails. Front brakes were smoking and just faded as we got to the bottom of the mountain. Shocks were very hot (especially the front). Cracked a shock mount (upper rear passenger).

Sunday evening we went out to a lake. All highway/city driving. On the way back, as soon as I got over about 25km/h, started hearing grinding/slapping from the t-case area. Noise goes away in 4x4.
Couldn't see anything obvious, so I removed the front DS (that's a whole story on it's own) and continued on our way home. Rode dead smooth and no noise. So, something is going on between the front output and the drive shaft, but I can't think of any definitive answers without pulling the t-case apart. I figured it had to be a stretched chain, or perhaps we chewed out one of the front output bearings, so I hopped under the Jeep this morning with a 1 1/8 socket on a drill and gave it a spin as fast as my drill moves. No noise in forward or reverse. WTF?

I figure if my chain is stretched far enough that it's slapping, I should be able to reproduce the sound with the drill. All I can think at this point is that somehow my driveshaft was making the noise. It was definitely about cooked already and I knew this, but it wasn't making noise on the trail, nor on the way home or out to the lake. All mild driving, park the Jeep for a few hours, get back in and lots of noise.

Anything obvious I'm missing? The case has gotta come off anyway as I've got a small leak between the trans and case, but if I can avoid disassembling the case because the answer is something obviously not inside the case, that'd be awesome :). I've got a long road trip this time next week through the mountains (all highway most likely) and my back is sorta killing me right now and I don't want to aggravate it if I don't have to.

New DS from TW is on the way and should be here Thursday, so I figure I can throw it on then and see if the noise has miraculously gone away, but either way that case has gotta come off for sealing anyway.
 
So I forgot to mention this. I was definitely having problems with heat under the hood after closing in my scoop. Those headers just get way too hot and were starting to bubble paint, even when the motor itself was well within' safe temps.
This is what I did to solve it.

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Just two big holes on top covered with perforated sheet. Works perfect. Underhood is nice and cool again, and I'm no longer forcing the under hood air pressure up, so the rad works better to boot.
 
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Finally reworking the chev harness.
47c4da849549952aaf755b084a910d81.jpg


It's really not too bad. I did however discover too late (after finishing the driver side) that chev apparently used the same length wires on several routing configurations, and didn't bother to cut them down. They instead just folded the wire over in the stock harness, so half my driver side is too long :) Whoops.

Spent about 4 or 5 hours at an easy pace. All stripped and mostly all cut down to the correct length. The harness will stay on the firewall all the way and it's looking like by the time I'm done, it'll be under 1" thick. Won't even be noticeable in there by the time I'm finished (hopefully tomorrow. Ran out of shrink tubing.).
Honestly, not difficult at all. Often obnoxious and very time consuming. If I'd done this with the motor on the stand, I could've probably had it complete in about 2-3 hours now that I know what I'm doing.

*note* - Do it on the stand before the motor's in the Jeep. Cut down all the motor stuff to fit along the firewall, and just separate all the stuff that'll tie into the XJ harness (assuming you're doing it that way) and stick a few plugs on. Requires about 10 connections assuming you bundle your 12V+ sources into a few manageable stacks.
 
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Mint. It's pulling 0-60 in barely over 6 seconds on 35's. 18-19mpg highway. The essentially unlimited low end torque combined with the automatic makes much bigger stuff easy.
I think I'm still running the factory spark plugs.
 
That's awesome. After reading your thread and photojareds I have decided to pull the plug. I bought a 6.0 with 45k on the clock and a 4L65E for 1400 delivered to my door.


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