So, I've been toying with the ideas and have done my basic research, but I need some help on some conflicting information I'm finding. I'm considering a 88-94 (preference going to the 88-91 for removable top) blazer, but I haven't bought anything, and pretty set on that year range. Mostly the goal is for a capable daily driver that'll put down some good numbers after a cam, headers, and whatever else ends up grabbing my fancy. I've considered FI down the road, but thats not even worth considering at this point.

I'd LIKE to do a 5.3l swap with a manual trans and keep the 4wd. The NV4500 is too pricey. For that reason, I'm looking seriously at just going with a 98+ 4l60E, and keep the NP241. If I find a SM465 blazer with a solid drivetrain, I may stick with the stock trans and just swap the 5.3 in, but I'm open for input on the plusses and minuses there from those who know.

If I went the 4l60E route, I'd probably end up picking up an HPTuner eventually and tweaking the hell out of it (couple buddies of mine used to be big into LS camaro/TA/GTOs), but thats a ways down the road.

Plan on a Yank TLT2600 converter

03+ LS6 cam/upgraded pushrods/springs

Shoenfeld Headers

mounts seem simple, trans will bolt in if I find a 700R4 truck.

cooling will be an electric fan, factory radiator

Stock power steering lines should work on the old rack

corvette fuel pump

truck PCM and intake are preferable

Probably going to go with a reworked factory harness. Anybody have tips and tricks on making that work relatively easily?

I intend to use the factory dash out of a newer truck to match. I think cutting the radio out of the stock dash should give enough room and with a little creativity can be made to work.

so, with all that in mind... I guess suggestions? input? anybody have help for what I'll need that I am not thinking of?

 

Your off to a good start. Lay it all out before you buy any parts make sure its all what you need.

Get a 91 with a 700R4 if you can. You can swap in a 5.3/4L60E from a 4x4 and use the NP241 for a pretty nice set up.

 

Can you elaborate as to why you're suggesting that particular year and drivetrain? Assuming its just because the trans cases are the same? Is there something more with the chassis that is preferable, or is that just the trans that came in the 91+?

Any chance of doing this without changing driveshaft lengths? with the 700R4 and the NP241 being OEM, I'm guessing yes? The other question mark I think is the output of the 4l60e matching the input on the NP241. When did they change? I know there are adapters available for the NP241, and rebuilding it wouldn't be a terrible idea anyway.

Other than the loss of control over the trans, would just using the 700R4 be an absolutely terrible idea? I'd bet the ECU would have to have the programming for the trans dropped, or use a manual trans ECU? not sure on the compatibility/effects of that kind of stuff on this setup.

The other big question is headers. Looking for a decent, cheap short-tube header that will work.

 

The reason I said 91 is that in 90 and 91 they used a electric speedo in the Subs and Burbs. The VSS ( vehicle speed sensor ) is located in the tail end of the transfer case. and is a 40ppm just like what the 99 and up ECM wants to see.

You can use a 700R4 but the ability to change shift firmness at the touch of a button is SO SO nice. I strongly suggest a complete pull out from a 4x4 99-02 GM truck. The 4L60E is a 27 spline just like what the 700R4 was. If you keep the transmission to tcase adapter off of the 99-02 truck it will bolt directly to the NP241 with no issues.

As far as headers... don't know man, never ran them on a LS yet.

 

I've got a line on a 5.3 for $500, with 40K on it, complete with harness. Don't know what its out of yet, but if its the wrong intake mani I can live with that for the time being.
as far as the VSS, I was planning on running all of the newer equipment, all the way to the cluster, but knowing the compatibility does make things easier though... almost encourages me to stick with the 700R4 for the time being, but yes, control over the shift and the converter lockup is definitely worth the 700 or so it would cost, I'm just looking at staging this into reasonable budget friendly pieces, and the engine would be the first priority.

So all the 4l60s are the same output? that simplifies things on the other end, and should make keeping the axles factory simple.

btw, thanks a bunch for your input!!! This (potential) project is a lot of new ground for me, so the feedback helps a lot. The more research I do on this, the more I want to get my car sold. haha

 

OK, revival time. I've found that the 03+ 4L60e is a stronger trans... is it the same in/output?

Also done some research on the chassis end of things. Al's liner looks like a great interior option.. and the wheel compatability of basically EVERYTHING is pretty slick.

 

anyone used a 91 or older shift linkage on a 4l60e? Is it remotely easy?

I found an 89 Jimmy with no drivetrain in it... body is solid. Trying to get my car sold like... yesterday so I can get this project up and running.

 

Used the shifting linkage that came on my 79. Remove the cable shift arm and replace with one from a 350 turbo, direct fit for me, no adjustment needed.

 

awesome. so the 700r4 should swap linkage with no issue what so ever.

So I just gave notice at my job, and my 130 hrs of PTO paid out should cover the chassis purchase... going to take a look at it next week:

 

So I looked at the above truck, and it had wicked rust scale under it, and was pretty much a mess. I'd have to pick up a chassis from down south, it just wasn't worth it, so I found another way to join the LS family.