47 3100 S10 SWAP need your input

[ibbowhunting]

OK, Ive been doing some reading and gathering parts and donors heres what I'm starting with

47 Chevy 3100 mostly a complete shell
78-350 SBC /350 turbo I pulled it from a truck of mine at least 5 yrs ago and in needs a rebuild
1994 GMC S15 long box regular cab 2wd 2.2 manual
2000 Chevy S10 Blazer 2 door, 2 wheel drive with what looks to be 2/2 drop installed, 4.3l, 200,000 miles, guess 4l60e
code 504 swap kit,( I didn't buy it came with the truck as a package deal)
4x4 blazer rear end
700r4 ( still looking)

So what should I keep from the blazer? Other then the front spindles,the bigger brake set up and the drop blocks? is the master cylinder different? Should I install the blazer master cylinder set up vs the one from my donor truck? The rear end in not ideal from the 2 wheel drive blazer, right? Front and rear sway bars? how about the gas tank? It sits between the frame rails behind the rear end any body used one? how about the 4l60e, I'm I better off finding a 700r4 and not messing with a computer? I'm also planning of keeping the serpentine belt drive from the 4.3 for the 350

Any idea what the ride height would be like? the body kit says it sit 2 1/2 lower then stock which I really have no idea what height that is, so if I put in the 2" drop in the chassis that would put me at 4.5" lower then stock any idea if thats dragging on the ground or roughly the front bumper height would end up like?

both donors are 1994 or newer is it worth saving the wiring harness from either or is buying a 12 circuit harness just a whole lot easier and cleaner

any of the a/c parts useable?

I will be grabbing the steer column, gas petal from one of the two donors

thanks for your input in advance

[mongocanfly]

if you've got storage space for all the vehicles I wouldn't get rid of anything until your done....read thru skymangs how to builds..he lays it out pretty well...joedoh also has done a many of these swaps..

[joedoh]

if you are switching to blazer brakes (F/R) you will want the blazer master and probably the booster. the 94 will have a steel brake pedal/steering column bracket you can use. you will ALSO want to save all the brake lines from the blazer, switching to blazer brakes takes either modified truck hoses OR the complete blazer line setup with hoses. drop blocks will interchange but remember that blazer leafs wont fit the truck frame (you didnt ask, it bears mentioning).

the 2wd blazer rear axle is the same width as the 2wd truck axle, so either one of those and you will need low offset wheels or 2" spacers. the 4x4 blazer axle will bolt right to the truck leafs and driveshaft and you wont need any spacers.

you can use the saddle gas tank from the s15, no need to put in the blazer tank. with the way the rear frame and bed works on an AD truck, if you used the blazer tank it would likely be the most visible thing since the great wall of china.

you will need a controller for a 4L60e, and you wont be able to use the factory ECM from the blazer unless you keep most of the engine controls and even the body computer. they sell stand alone computers for controlling a 4L60e, you will find used 700R4 transmissions are cheaper.

ride height with 3" drop springs and body mounts that are 2" lower will look like this


since you are going to an old 350 I wouldnt recommend using the 94 harness (the only one you would use unless you were swapping in the entire drivetrain and computers of the blazer). an aftermarket harness is going to be less work than paring down the 94. again, do NOT use the blazer harness unless you are keeping EVERYTHING, the blazer steering column, the blazer tank, everything.

When I did my 03 s10 4.3 swap and kept EVERYTHING I found a 98 tahoe AC/Heat box plugs right into the s10 heater controls and just barely fits in the dash. the S10 ac stuff is all mounted outside the firewall and wont fit on the firewall of the 3100.

use the 94 steering column, and column mount as I said above. make SURE you grab all the column wiring and brake stuff too like the switch. gas pedal from either will work. maybe. keep them both.

have you read the skymangs sticky thread on s10 swaps? lots of good info there.

[mr48chev]

On the drop spindles, put the truck together with the stock spindles off the long bed, run it around the block and then back up and look, Delayed process yes but you won't have to undo it if you put it together with the drop spindles and don't like them I am thinking that I will need a set for my stock frame with Industrial Chassis Dakota crossmember and Dakota suspension but I'll wait until it's together to make a final decision. For you it's a two hour process after you have it together to change spindles so it isn't a biggie.
I think the other guys are doing what you are thinking of on the brakes, the one in question matches the brakes on the truck and keeps things simple. It might not be as pretty or fancy as some aftermarket ones but you won't be worrying if it is going to stop right.
A few years ago I drug home and 86 S-10 4x4 blazer because I wanted the rear axle and the gas tank, It was free for towing away before scrap got high and there wasn't supposed to be a title with it. Got it home and looked under it the next day and no gas tank. Finally pulled it apart and pulled the rear axle and there were about 4 teeth out of the ring gear and the pinion had severe dental problems. Gave some pieces to a coworker who needed them for her Blazer and started taking it apart. Got the body loose from the frame and flipped it off and the glove box popped open and there was the title. Half hour later the shell was at my friend's wrecking yard in his crusher pile. The frame and what was left of the engine and trans went to scrap. I ended up giving the rear axle housing to the husband of one of my former students who needed it because his housing in his rig was bent but the rest was good.

[joedoh]

I didnt see where he said spindles, but let me say if you have a 98+ blazer with 2" drop spindles you are very lucky, because they are only made by belltech and are $400. look for a casting number of 2102 on the backs.

a 2/2 drop on a blazer is usually coils and blocks.

[mongocanfly]

also bears mentioning that a zr2 rear is 3in wider than a standard s10...it also has disc brakes and 3.73s with a g80 locker...they're a little harder to find

[ibbowhunting]

i was hoping for drop spindles on the blazer but at first glance looks like shorter coil springs in the front

[ibbowhunting]

Originally Posted by mongocanfly

also bears mentioning that a zr2 rear is 3in wider than a standard s10...it also has disc brakes and 3.73s with a g80 locker...they're a little harder to find

Is the standard 4x4 blazer rear end the same width but without the locker right?

I got what i was told was a s10 blazer 4x4 rear diff with my truck but how do i tell it is what i was told it was? it has disc brakes that's a start right

[ibbowhunting]

Originally Posted by joedoh

if you are switching to blazer brakes (F/R) you will want the blazer master and probably the booster. the 94 will have a steel brake pedal/steering column bracket you can use. you will ALSO want to save all the brake lines from the blazer, switching to blazer brakes takes either modified truck hoses OR the complete blazer line setup with hoses. drop blocks will interchange but remember that blazer leafs wont fit the truck frame (you didnt ask, it bears mentioning).

the 2wd blazer rear axle is the same width as the 2wd truck axle, so either one of those and you will need low offset wheels or 2" spacers. the 4x4 blazer axle will bolt right to the truck leafs and driveshaft and you wont need any spacers.

you can use the saddle gas tank from the s15, no need to put in the blazer tank. with the way the rear frame and bed works on an AD truck, if you used the blazer tank it would likely be the most visible thing since the great wall of china.

you will need a controller for a 4L60e, and you wont be able to use the factory ECM from the blazer unless you keep most of the engine controls and even the body computer. they sell stand alone computers for controlling a 4L60e, you will find used 700R4 transmissions are cheaper.

ride height with 3" drop springs and body mounts that are 2" lower will look like this


since you are going to an old 350 I wouldnt recommend using the 94 harness (the only one you would use unless you were swapping in the entire drivetrain and computers of the blazer). an aftermarket harness is going to be less work than paring down the 94. again, do NOT use the blazer harness unless you are keeping EVERYTHING, the blazer steering column, the blazer tank, everything.

When I did my 03 s10 4.3 swap and kept EVERYTHING I found a 98 tahoe AC/Heat box plugs right into the s10 heater controls and just barely fits in the dash. the S10 ac stuff is all mounted outside the firewall and wont fit on the firewall of the 3100.

use the 94 steering column, and column mount as I said above. make SURE you grab all the column wiring and brake stuff too like the switch. gas pedal from either will work. maybe. keep them both.

have you read the skymangs sticky thread on s10 swaps? lots of good info there.

got any pictures of that a/c/ heat setup with controls installed ?

[mongocanfly]

s10 axle widths are...2wd 54.5"...4wd 59-60"...ZR2 63"

[joedoh]

Originally Posted by ibbowhunting

got any pictures of that a/c/ heat setup with controls installed ?

I do, I have to get them from my archive disc though because they were in the build thread (49 3600) but photobucket took all the pictures down and I changed laptops at the beginning of the year.

the tahoe box barely fit between the dash and the firewall, I had to remove the tahoe air distribution system (vent defrost floor flaps) and I had to put an orifice tube in the lower AC hose. the cold/hot worked in reverse, I had the controls mounted in a very shallow glovebox.

it is a moot point though if you dont use the 2000 blazer harness, I used my 03 harness so all the HVAC worked like factory. with an aftermarket harness and 350 I would just buy an vintage air underdash setup.

[ibbowhunting]

Originally Posted by mongocanfly

also bears mentioning that a zr2 rear is 3in wider than a standard s10...it also has disc brakes and 3.73s with a g80 locker...they're a little harder to find

so the extra width of the ZR2 rear diff is even better

[mongocanfly]

in my opinion...yes..