72 Blazer_2wd LS swap but remove front driveshaft

[NDM]

Hello. I am new here and recently purchased my bucket list 72 4x4 Blazer with the factory 350. I planned to do an LS swap and eventually a 2wd swap but for the moment I need I only have the funds for the LS swap. So my question is this. Due to the fact that I am preparing for a 2wd conversion, I want to pick up a 6.0 L96 and a 6l90E trans from an 3500 express van. The reason for this motor/trans combo is because I am very familiar with it since I also have a 1976 Buick Regal with the same combo. These motor/trans combos are plentiful and cheaper than LS3's. The 6l90E is very stout and handled a bunch of power.

So is it possible for me to run the front 4x4 axle but with no driveshaft connecting it until I build up the funds to do a proper 4x4 to 2wd conversion. technically I could do the swap now but I would have to change wheels and tires which would be a bunch more.

If you are wondering why I just dont wait to do everything until I have all the funds needed, well I actually sold my daily driver (60k mile 2013 Jeep GC SRT) to get this Blazer. I need to be done with the swap and have all the bugs sorted before the next Chicago winter rolls in.


My only other option is to pick up a 4wd motor and trans from a modern chevy truck and run 4x4 for a while but then I will be wasting funds when I swap to 2wd due to things like having to buy 2 new driveshafts and having to swap the trans to a 2wd or modify the 4wd trans. I would rather just drive around with 2wd and leave the front axle with no shaft but still operational.

So is this possible to do?

[Thealien]

I don’t see a problem with it. When the transfer case is not in four-wheel-drive the front driveshaft doesn’t spin anyway and if the hubs are unlocked nothing is moving.

[DeadheadNM]

Forgive me for asking but why bother to convert it to 2wd at all?

[NDM]

Originally Posted by DeadheadNM

Forgive me for asking but why bother to convert it to 2wd at all?

Because I wanted a 2wd but they are not very plentiful and cost a great deal of cash to get. I was able to land the 4x4 in great condition with a single wall top and newer interior for a reasonable price.

My plan for it is to be similar in performance to my SRT Jeep but just 50 yrs older. This will be my daily driver. I am not completely opposed to keeping 4x4 but If I do the suspension would get completely revamped because lets be honest, these things in 4x4 ride.....um... not the best! Lol!

Trust me though, 4x4 or 2wd, I love this thing and you will soon see some lenghty threads about my modifications that are coming soon.

[NDM]

Originally Posted by Thealien

I don’t see a problem with it. When the transfer case is not in four-wheel-drive the front driveshaft doesn’t spin anyway and if the hubs are unlocked nothing is moving.

Sweet. As I stated above, I am not completely opposed to keeping 4x4 but my dream was to have a fantastic sport truck with the performance of my old Jeep Srt.
I am unlikely to ever really take it offroad but I will tear up some asphalt on a daily basis!

If I can, I might lsa the thing or turbo.

I am sure I will be digging extensively through your ls swap link.

[NDM]

Originally Posted by Thealien

I don’t see a problem with it. When the transfer case is not in four-wheel-drive the front driveshaft doesn’t spin anyway and if the hubs are unlocked nothing is moving.

Okay,
How about this-
What would happen if I got a 4wd 6l80/90 with transfer case and swapped the Bucket list blazer as 4x4....But then.....When I am ready to swap to 2wd, I just remove the front drive shaft and axle???

Would this work? Sorry, This is my first dip into the 4x4 realm.

What would be 100% awesome is if I could keep 4x4 but lower the blazer to look like a 2wd. Then I could essentially have something like the SRT which was AWD, low and handled like it was a heavy sports car.

No matter what, the leaf springs will be going bye bye. I have built many 4 links and this thing is calling out for a leaf to airspring swap.

[Thealien]

Most newer transfer cases are drivers side drop and ours are passenger side drop. So to use the newer transfer case you would need a different front differential or rework yours.

2 wheel drive and 4 wheel drive transmissions generally have different tail pieces and output shafts so its not so easy to make it work.

[NDM]

Originally Posted by Thealien

Most newer transfer cases are drivers side drop and ours are passenger side drop. So to use the newer transfer case you would need a different front differential or rework yours.

2 wheel drive and 4 wheel drive transmissions generally have different tail pieces and output shafts so its not so easy to make it work.

Ah. Good info there. So, maybe I can adapt the factory tc to a new trans or pull a newer front axle from a yard?

[Thealien]

They make an adapter and output shaft to install a 4L60 transmission to an NP 205 transfer case. I know they make all kinds of adapters. I do not know of any adapters for the six speed transmissions but there may be?

[NDM]

Originally Posted by Thealien

They make an adapter and output shaft to install a 4L60 transmission to an NP 205 transfer case. I know they make all kinds of adapters. I do not know of any adapters for the six speed transmissions but there may be?

https://www.advanceadapters.com/gm-c...0-29-spl-trans

Looks like you are correct. Thank you!
Now I have to wonder how much power thw np205 can take.

I guess I need to make up my mind.
A-L96, 6l90e 4x4 with stock TC adapted
B-L96' 6l90e 2wd with front driveshaft removed (prepare for 2wd swap)
C-L96 6l90e 4x4 new TC with possible newer front alxe swap
D-???? Other/unknown

[Thealien]

NP205 transfer cases are pretty stout. I would not hesitate to run a good condition NP 205 behind just about any power plant.

You have to decide what you want to use the vehicle for. If you’re never going to go off-road or very rarely the ride quality of a coil sprung 2 Wheel Dr. is far superior to the four-wheel-drive suspension. It is exaggerated due to the short wheelbase.

Originally Posted by NDM

https://www.advanceadapters.com/gm-c...0-29-spl-trans

Looks like you are correct. Thank you!
Now I have to wonder how much power thw np205 can take.

I guess I need to make up my mind.
A-L96, 6l90e 4x4 with stock TC adapted
B-L96' 6l90e 2wd with front driveshaft removed (prepare for 2wd swap)
C-L96 6l90e 4x4 new TC with possible newer front alxe swap
D-???? Other/unknown

[hemi43]

Originally Posted by NDM

Now I have to wonder how much power thw np205 can take.

More power than you can throw at it.

[NDM]

Originally Posted by hemi43

More power than you can throw at it.

I wisjh I had the kind of money necessary to test that statement!

[NDM]

Well, I think I have decided on my motor, trans and 2wd vs 4wd woes. I have agonized over the decision for a while now and it all boils down to complexity.

What I want-

I want to run a 6.0 or better LS motor with a 6l90E trans.

I want to eventually do a 4x4 to 2wd conversion on my blazer

I want a smooth ride.



Issue-

Many people love the look of the blazer up high. I like it too. It rides like crap though and although there are ways to make it ride better, It will never be smooth like Butter.

I would run 4x4 but I need a bunch of Expensive adapters and I have to machine this and modify that. I am not wanting to do all that to run what is going to be a temporary thing.

The adapters are about 8-10 weeks out to get to me so that will put me dangerously close to not having my LS swap done by winter.

I eventually plan that 2wd conversion so spending a bunch of bread on parts to temporarily run 4x4 is just not smart IMO.



The solution-

After talking with a bunch of manufacturers about the specifics of all these adapters, I realized the right thing to do.

-Buy a 6.0 LS motor (or better) with a 2wd 6l90e and all the parts needed to do the swap. Remove the factory 350 and th350 trans with the np205 transfer case as well as the front driveshaft. This will mean that I will be running the same suspension but without 4wd. I will then be able to save up for the 2wd swap while still being able to enjoy my fuel injected 72 Blazer to the fullest. I could fab up a 4 link suspension for the front and rear and install airride which will solve the ride issues. Once I have the bucks for a full 2wd swap, I will not have to change out anything but the front suspension and rework the rear 4 link with the new ride height.



Every box will be checked with this solution. I am very familiar with the 6.0 and 6l90e swap because my Buick has the same combo. Everyone who loves the higher up look will still see it higher up for the time being. I wont have to go buy a bunch of $800 adapters and pay any machine shop to modify anything. Most importantly, WHEN I swap to a 2wd front end, I will not have much work to do to make it work.

[NDM]

AGGGHHH!!!

So frustrating! Motor will not start! I am pretty sure it is flooded. This is why I do not want anything to do with carbs. I am lost trying to fix the issue but if I had the LS installed I would have hooked up the computer and already know the issue.

[SeventyOne]

Just a few things to add from reading through this:

I am pretty sure you wont be able to lower the 4x4 suspension with the LS in place. I think the crossmember/oil pan interfere with the Dana 44 differential.

If you can figure out how to get an LS to run you can figure out a carb on a SBC. They're dead simple. First I'll just say that 99% of carb problems are ignition problems. if you're sure the ignition is up to snuff (aka you have spark and timing is in an acceptable range to start) then move onto looking at the carb.

If it is actually flooding you can clear the flood by cranking with the throttle and choke held open. Flooding = too much gas, open the throttle to let in more air. Have a fire extinguisher handy just in case.

But you should find out why it's flooding. Check the floats and needle/seats. What carb is on the engine?

If you want to do a test: disconnect the fuel inlet and run the fuel line from the fuel pump to a gas can. Then fill the fuel/float bowls with gas - dont need too much - then try to start it. There wont be any fuel pressure from the fuel pump to override the float + needle/ seat and you can see if it will start with just the fuel in the bowls.

[NDM]

Originally Posted by SeventyOne

Just a few things to add from reading through this:

I am pretty sure you wont be able to lower the 4x4 suspension with the LS in place. I think the crossmember/oil pan interfere with the Dana 44 differential.

If you can figure out how to get an LS to run you can figure out a carb on a SBC. They're dead simple. First I'll just say that 99% of carb problems are ignition problems. if you're sure the ignition is up to snuff (aka you have spark and timing is in an acceptable range to start) then move onto looking at the carb.

If it is actually flooding you can clear the flood by cranking with the throttle and choke held open. Flooding = too much gas, open the throttle to let in more air. Have a fire extinguisher handy just in case.

But you should find out why it's flooding. Check the floats and needle/seats. What carb is on the engine?

If you want to do a test: disconnect the fuel inlet and run the fuel line from the fuel pump to a gas can. Then fill the fuel/float bowls with gas - dont need too much - then try to start it. There wont be any fuel pressure from the fuel pump to override the float + needle/ seat and you can see if it will start with just the fuel in the bowls.

Thank you for your tips.

I did find the issue though. After taking the carb apart, I figured that I would give it a good cleaning. Immediately after removing the passenger side bank float I knew want the issue was. It was filled with fuel. I then realized thae my Buick had a similar carb before I ls swapped it. I swapped the float and vrooom! Problem solved...........but.........then I realized that the throttle cable had ripped through the sheath. So now I need to fix that!

Geez, I cannot wait to have drive by wire!

[NDM]

And as a follow up, I am now back in business. I bought a Mr. Gasket throttle cable from my local O-O-O-O'Reilly's Auto parts and within an hour I had the cable hooked up and started tuning the carb.

After the carb was tuned via vacuum, the truck ran noticeably better. Apparently the engine does not like fuel pissing into the left bank. Who Knew!
Not a bad job for a young chap with only amature EFI tuning experience!