'90 to '86 to TPI swap!

[BIGGREEK]

Hey guys! I have been in the Blazer "world" since 2002 when I got my first Blazer. I was 12 years old at the time and I was uber excited. Well, as school/time went on I had many ideas and an awful lot of day dreams. The truck needed a lot of work (rust) and I had the ambition to take it apart, but it stayed apart. As more time went on, I started driving and got my first drivable car, a 2008 Vw Rabbit, after that I was bitten by the bug. (Vw fever, here we come!). After 2 years with the Rabbit, I decided to buy another VW (to keep the miles off of the new car (85k miles in 2 years), a 1987 Mk2 Golf. That itself was/is still a project.

Then a buddy of mine was restoring (haha, really?) his blazer and bought a parts blazer for the extra parts (duh) and mainly the transmission. I went to go look at it and it was a CLEAN truck. Very little rust, pretty straight forward (the PO rolled it on its side but fixed the damage (properly), It just needs some quarter panel work and some roof work and that's it. So....what did I do, buy it for an amazing deal (200 bones + a cheapo muzzle-loader). He gave me the 305 block that came out of it, a set of std 350 heads, a 307 (almost complete) motor, and two TPI setups (Old and new style).

Before I bore you guys to death lemme start telling you about the project.

The 90 Blazer:

Here it is currently.lol

It started off as a EMS truck in NYC and had a pretty hard life, the PO took care of the mechanical work but the rest (of course out of his control) turned to RUST.

The newly acquired blazer is a 1986 with 136k on the clock.
VERY little rust, compared to the 90.

Now my plan is to throw EVERYTHING from the 90 into the 86 convert it to TPI (its been changed over from MAF to MAP and its tuned). Throw the 3/4 ton axles underneath from a suburban I have outside. Lift it a bit, clean it up, paint it, etc. blah blah blah. Just get it lookin and rollin good.

Now I do have a few questions, I havent been in the Blazer field for a few years and my mind is getting fuzzy. I am wondering how I can swap this TPI over. I have ALL of the wiring harness that has to do with the TPI system, the system that takes the new style heads. I know the bulkhead connector is the same (correct me if im wrong). Will I run into tranny issues, cluster issues, starting issues? Help me out!

 

[86TPIBurb]

Should not be a problem...I did with my 86 Suburban. The only issue you will run into is the center bolts on the intake manifold. unless you can find an 85-86 TPI manifold, you will have to drill out those center holes. PM me if you need more info. Did your 86 setup have the computer controlled Carb? I`m looking for the computer carb harness and ECM.
Jim

 

[BIGGREEK]

Should not be a problem...I did with my 86 Suburban. The only issue you will run into is the center bolts on the intake manifold. unless you can find an 85-86 TPI manifold, you will have to drill out those center holes. PM me if you need more info. Did your 86 setup have the computer controlled Carb? I`m looking for the computer carb harness and ECM.
Jim

Im just using the body/frame from the 86. All of my "accessories" (motor/trans/etc) are all coming from my 90. So i have the center bolt heads. And i also have the 85-86 intake as well as the newer style (so I got 2 setups). As far as the computer controls on the 86, i have no idea. I haven't really looked into the truck for wiring, computers and such. Plus the guy that i got it from was torch happy, so all of the wiring under the hood is trash. Ill let you know if it has the ecm and some of the harness.

oh btw, I found out that i have a chip tuned 730 ecm...i think i have a pretty much plug and play system.lol

 

[86TPIBurb]

If the 730 ECM is already tuned for the truck, its as simple as installing a fuel pump(i would suggest inline) as close to the tank as possible, return line should already be there, and bolting up the TPI unit.
I ran EFI rubber lines to my fuel rails, from the stock fuel lines on the right frame rail, near where the old mechanical pump was.
The only real pita is mounting the ECM, behind the glove box should do, but watch that you dont catch some wires on an A/C door motor.

 

[buefchris]

Make sure your cam is the correct one. Stock TPI ECM's will only run a small choice of cams.
Or, if you decide to use a aftermarket OBD2 computor,your range will be much broader.

 

[86TPIBurb]

I have a Compucam 12-388-4 256 cam....Sorry I did it. eventually, i will get around to installing a short duration roller cam, since my block is roller ready.

 

[BIGGREEK]

long lost thread has risen.lol I can now post pics.

Here is the 90 back in april getting ready to leave, as you can see not much left

and here it is with no axles, no windsheild and the body hasnt been cut up yet...

That was 5-6 months ago...


For the past few weeks ive been working on the blazer since the 87 golf acquired some problems that put it off to the side.

So this is what I have done so far...

removed all of the brake lines, fuel lines.....everything. All that is left is the axles, then she goes for sand blasting.

btw there is the burban the axles are coming off of.

and this is how the cab sits now

So my plan now is to rebuild both axles, install new suspension/steering components, and add a locker the rear. Now the gears im thinking of are 4.56s, im thinking that is going to be OK (running 35s and the 4l60 (700r4) from the 90). So far I have a list of at least 3500$ JUST on the frame/axle stuff (tell me im crazy).

 

[86TPIBurb]

What were you going to do with your TBI Stuff?

 

[BIGGREEK]

probly sell it, and the truck ran great when I pulled it apart. But im probobly going to wait on digging through that stuff until I get this frame situated and ready to drop the motor in place.

 

[BIGGREEK]

Well some updates since september.

Completely stripped the frame of..everything other than the paint. Now im awaiting a "tow" to the sand blaster for a good ol' blastin. Then once I get it home, I will shoot it with POR 15 so it will never rust.haha So that is what's really holding me from putting it back together.

BUT the other day I hit a huge wall. Remember that 350 i was going to use out of the 90? Yea....its sitting outside awaiting it ride to he!!. The person who "rebuilt" this motor was either blind or was 12. When I pulled the oil pan, there was quite a bit of water mixed in the oil. So I started to wonder....I pulled the heads and I found this:

So there was a nice "groove" in the cyl wall. And these have been bored .030" over already, so now there is no chance this block will last if i bring it out to .060", especially if I knew its been through hell.

So there has been a change of plan. Looking for a vortec motor, bottom end and heads. Supposedly that is were the power's at. Now its not on the priority list, so now i can spend time on the frame aspect and not so much the motor yet.

So plan as of now for the motor.

Vortec block, bore it .030" over
Worked vortec heads
about a .500 cam with a pretty good low end duration.
the tpi setup, with edelbrock lower tpi/vortec baseplate
Either SLP or Edelbrock high flow runners (not so much the AS&M LTRs because that is for higher end performance).
The 24# injectors out of an LT1 I just picked up (and dropped one today, so I will need another one, if anyone is generous enough to "give" me one, I will gladly take it.lol)
Forged crank, forged H-beam rods, havent decided on pistons yet.

SO that is where I stand as of now. All I have to do is play the waiting game, then the game will start.

 

[str8axle55]

The Vortec lower end isn`t anything special, it`s all in the heads, and the springs are done @ 450-480 lift. It sounds like for the $$ you are going to spend on the axles,you could get real 1 tons out of a CUCV, 4.56`s w/Detroit rear, and never worry about them again. Looks like a cool build though.

 

[BIGGREEK]

Thanks man, the only reason why I want the vortec bottom end is that its already a roller block, so I can get a few more horses out of it just by it being roller. And this motor is getting a complete rebuild, so the only thing factory in that motor will me the block itself and the heads bare.

And Ive had tons of people tell me to go with the ff..but the thing is, is that I already have the 9 1/2s, and I don't have to go searching for axles, and I don't think I will put these axles in THAT much stress. Plus its a sh!t ton stronger than a rinky dink 8 1/2.

 

[Ktm15]

very cool! lotsa work there! looks like your handling it just fine! good job man! may i ask hw to post pix? i see you posted a couplr posts back,you can post pics again? i cant! hahaha

 

[BIGGREEK]

thanks man. You would need atleast 5 posts to post pictures. Then you would need a photo sharing website account. Then you could copy and past the links over to your thread/post.