5.3L Vortec V8 Conversion

[1991Jeep_Man]

Yes, in the event of a short or something you will be stuck looking for an answer. It's no different than any other connector/switch/sensor. It is pretty straight forward and easy to find info though.

I have a friend who did a conversion back to a cable and it did add a lot of hurdles to the project. All the things you mentioned and more.

Well, with that I guess it's DBW or bust. And when it comes to this monster 5.3L swap, I refuse to bust lol. Another quick q: does the new pedal assembly sit differently than the stock pedal? Or can you swap the stock pedal onto the DBW assembly? I guess what I am trying to ask is does it take some getting use to?

 

[John D]

I had to cut and reweld my pedal arm to fit and I did not have any trouble getting used to it.

 

[Serious Offroad]

Check post #1.

My motor is an '03 with a DBW system.

Forget what you've heard about throttle lag.

Reliability is a concern with any electronically controlled motor, as Jeep owners we've all learned that lesson many times over.

FWIW,
I have a spare TAC module...just in case.

 

[1991Jeep_Man]

I will also be contacting FFDynamics again because I am very curious to their contact with Frank about their system holding up to a 5.3L. One question I will ask is if it's possible to have the inlet and outlets on the rad swapped for better compatibility to the 5.3L. I will share whatever I find out on this thread.

 

[1991Jeep_Man]

Alright guys, I know Im bringing this to the front again, but a couple of questions.

My first is about the VSS. I was looking at Brendan's site for PCM tuning, and he said the VSS on a 4x4 vehicle with a manual tranfer case MUST have the VSS between the tranny and t-case. However, the stock location for the VSS on my XJ is in the t-case tail cone. If I looked at your thread clearly Frank, you used the same stock location didn't you? Any issues? If it matters, due to availibility issues and plus the possible generous donation of a relative, I will be doing a '96 LT1 swap; rebuilt LT1 from an Impala with the '96 redesigned (detatch bell, 6 bolt rear) 4l60e from a Tahoe.

Also, I was going to go your alls route to hook up the NP231J to the 4L60E; Chevy 27 spline input, upgraded planetary, and wider chain, then use a clocking ring for the best angle. However, recent contact with Novak is making me question my original plan. According to them, 27 splines are bad, using a chevy input in the NP231 is bad, the clocking angle would never work, and I should consider buying a turnkey 700r4 from them with the NP231 adapter ($2000+). I have a good feeling theyre just trying to suck me into tossing money at them. What do ya'll think?

Thanks for the help!

 

[Frank Z]

Yes, my VSS is in the transfer case output shaft tailcone and it works perfectly. Brendan's info regarding the VSS location for a manual tranny means nothing with regards to your swap since you are also installing an automatic. Be certain that you have the correct VSS for your PCM model year.

I won't comment on Novak's suggestions other than to say that I disagree.

Sourcing the parts to build a "Bastard" T-case is not difficult, just a bit time consuming. The right combination of parts can result in a very strong t-case that will bolt up without any problems at all.

I STRONGLY recommend using the JB Conversions NP231C short shaft kit. I wouldn't even consider using an OEM mainshaft behind a V8...any V8.

HTH

 

[John D]

I went a different way with my swap and used an AA adapter, so my VSS is mounted there between the tranny and t-case.

I also disagree with what you heard from Novak.

If you have difficulty finding the "Bastard" t-case parts locally (like I did) they are easily available from ebay. I got everything I needed from this guy for $142 shipped.
http://stores.ebay.com/powertrain-p...=5303410&_sid=369570213&_trksid=p4634.c0.m322

x2 on the output shaft conversion, don't consider it without one.

Good luck, you're going to love it when it's done.

 

[1991Jeep_Man]

Is this the shorty ya'll are talking about?

http://www.jbconversions.com/products/sye/np231c_short_sye.php

And if you both recommend it, then consider it added to my list. Thanks again for the help.

 

[John D]

I did my output shaft conversion many years ago so it is not the shorty. If I was to do one today I would do the shorty.

 

[Frank Z]

This one:
http://www.jbconversions.com/products/sye/np241c_std_sye.php

 

[1991Jeep_Man]

This one:
http://www.jbconversions.com/products/sye/np241c_std_sye.php

Thanks Frank! I'll be sure to grab one of these when I start the build. One question though; it says that this kit retains the stock tail housing. Being that my XJ is a '91, does this mean I need to add an NP231C tail housing to my 'bastard' list?

 

[Frank Z]

I used my "J" tailcone.

 

[scoobyxj]

On your issues with the gauges did you ever explore the idea of using TJ gauges? With all the V8 swaps into Wranglers I can't fathom no one makes a LS-to TJ gauge controler.

 

[Frank Z]

Supposedly Novak can mod a stock cluster to work with this swap.

After figuring out that my GM cluster was bad and I bought my VDO gauges....no problems after that.

 

[1991Jeep_Man]

Another quick question;

How did ya'll get the tranny skid/support remounted? My plan was, since Im using the stock NP231J tcase housing, to use a stock tranny mount, bolt it to the t-case like normal, then line the skid up evenly, drill 4 bolt holes through the bottom of the unibody frame rails like it's setup now, then drill 4 holes just large enough into the side of the frame rails to fit a boxend wrench with a nut in it, so I can slide a bolt through the skid hole, bottom rail hole, and tighten the nut inside the rail. My main concern is any structural intergrity issues with the 2 holes made on each side.

 

[Frank Z]

I used the GM OE rubber mount. I added a mounting point welded onto my cross member.

You need to keep in mind that that although your adding displacement you are in fact shortening your drivetrain length by 2 cylinders (so to speak).

I suggest you wait until the motor, tranny, and transfercase are in the heep before you plan your cross member solution.

 

[blubullett]

I see that you abandoned your first idea to use the stock manifolds but I was wondering if you think they could have been made to work without modding the framerails? Maybe by cutting and rotating the flanges? I don't have upper control arms so I would be able to cut the mounts out if the way. I want to do a 5.3 swap but here in California you have to appease the smog Nazis so that means using stock manifolds or CARB legal headers which the Novak ones aren't.

 

[Frank Z]

I suppose if a guy had enough time and a stack of manifolds he might stumble on the correct combination of angles to cut that would allow rotating the pieces just enough to point the flanges downward and still have adequate clearance.

I gave it a helluva try, and now have a set of Novak headers.

 

[John D]

A friend of mine did an LS1 swap in his XJ and he cut the flanges off the manifolds then welded the down tube to the manifold. I didn't think it was going to hold, but it's going on three years now.

I have also seen people cut that area out of the frame (like a notch) out and weld plate back in to make it strong enough again.

 

[Johnnie Walker]

I see that you abandoned your first idea to use the stock manifolds but I was wondering if you think they could have been made to work without modding the framerails? Maybe by cutting and rotating the flanges? I don't have upper control arms so I would be able to cut the mounts out if the way. I want to do a 5.3 swap but here in California you have to appease the smog Nazis so that means using stock manifolds or CARB legal headers which the Novak ones aren't.

My Heep is registered at my uncle's house in nor-cal that only has smog upon change of ownership (=
I am wanting to do the LQ swap but do not have enough funds yet. Have a list of things to do/get tho.