Converting '82 to '87 TBI???

[kevinr1970]

So I bought an '87 lwb 2wd truck today for really cheap. It is beat and really needs to be tuned up but didn't smoke at all and had no problem getting to and maintining 70mph on the drive home.
My questions are this:
I want to put this engine and transmission in my '82 2wd Blazer. What do I need to bring over as far as the harness or other things for the TBI?
If this has been covered can someone post a link.
Also, the brakes on this truck seem way more powerful than the brakes on the Blazer. Is there something different about the '87 brakes than the '82?
Thanks in advance for any help you can offer.

[1972C10]

If its a full size blazer you can transfer all the wiring directly

Friend of mine put a harness out of an 87 truck into a late 70s blazer it was a direct swap he pulled any and all wireing from the truck and swapped it . Got the later model colum out of the deal too.

[1976K5CHALET]

www.rockauto.com you can buy a 87 up K5 fuel tank with a steel baffle for cheap...you can get the 2 pulse vss from howell engineering for $85...and you can scrounge the fuel lines from a donor 87 up K5 if you would like. Since the 82 had a emissions ecm under the dash you can remount your 7747 ecm in its place....K5's are nice to swap efi into since 87 to 91's came with efi.

I've done both of mine that way and i drive them everyday.

DW

[Captkaos]

The wiring, as Doug said, it is a direct swap. Just get everything that was connected to the engine and unplug it. Pull the speedo (or the whole cluster) out of the '87 it has the VSS in it already.

The difference in brakes on the 87 vs 82. Well ALL blazers come with HD 1.25" brakes. Why the newer one feels better, no idea.

[kevinr1970]

Originally Posted by Captkaos

The wiring, as Doug said, it is a direct swap. Just get everything that was connected to the engine and unplug it. Pull the speedo (or the whole cluster) out of the '87 it has the VSS in it already.

The difference in brakes on the 87 vs 82. Well ALL blazers come with HD 1.25" brakes. Why the newer one feels better, no idea.

What is VSS?

If I unbolt the harness "block" from the firewall and then take everything under the hood I should be fine?
What about the harness inside the cab? Do I need to get anything there?
The truck has PW & PL and I would like to get those for the Blazer as well. Are they on a seperate "circut" then the main harness or are they all tied together?

[Captkaos]

You need the harness coming out of the ECM on the firewall. The harness section at the fuseblock would be ok to take, but if the corresponding pieces are not on the other side, then it won't be swappable. I can't remember if there were any harness changes comparing 82 to 87, but there will be some due to the fact that it is an EFI.

The wiring harness is on a completely seperate section and can be removed and swapped easily.

[1976K5CHALET]

VSS = Vehicle Speed Sensor.

I believe the cpt. is right about the harness. My first K5 (79) was converted with a howell harness....since its a stand alone sytem for the most part. The chalet i took a different route...i clipped a harness in a jyard and built it myself...i seem to remember there are a few wires that go into the main cab harness....i'd have to look in my library in the garage but i would assume it would be ecm/ fuel pump relay power and ignition power.

The 87 dash will have a box hanging from the back of the cluster...this is your vss....this was used up until 89....in 90/1 they went with a full electric speedo and the trans or xfer got a vss....which routed an analog signal to a DRAC ( digital ratio adapter located under the radio in the form of a white box)...the drac is burnt with some vital info such as tire size and ring gear ratio....it takes the analog signal and using the afore mentioned info calculates the info and spits it out in a digital form the ecm's (abs,engine) and speedo can use....not really as complicated as it seems...however getting the parts is a little tougher...gm does not stock the drac's or speedo's anymore but they are still ava aftermarket...the beauty of it is with some radio shack parts you can break the mystery of sorts and adjust the drac for gear and tire size mods...the other way you will have to have a ratio box made at a good speedo shop....

DW

[kevinr1970]

So would it be best to use a stand alone system or should I have most the parts in my donor?
I am moderatley mechanicly inclined - I can change parts and some diagnosis, I've done a few engine swaps but it sounds like this might be more than I bargained for?
If nothing else, I could do the mechanical swap and call in someone with more knowledge than me to button up the wiring issues?

Originally Posted by 1976K5CHALET

VSS = Vehicle Speed Sensor.

I believe the cpt. is right about the harness. My first K5 (79) was converted with a howell harness....since its a stand alone sytem for the most part. The chalet i took a different route...i clipped a harness in a jyard and built it myself...i seem to remember there are a few wires that go into the main cab harness....i'd have to look in my library in the garage but i would assume it would be ecm/ fuel pump relay power and ignition power.

The 87 dash will have a box hanging from the back of the cluster...this is your vss....this was used up until 89....in 90/1 they went with a full electric speedo and the trans or xfer got a vss....which routed an analog signal to a DRAC ( digital ratio adapter located under the radio in the form of a white box)...the drac is burnt with some vital info such as tire size and ring gear ratio....it takes the analog signal and using the afore mentioned info calculates the info and spits it out in a digital form the ecm's (abs,engine) and speedo can use....not really as complicated as it seems...however getting the parts is a little tougher...gm does not stock the drac's or speedo's anymore but they are still ava aftermarket...the beauty of it is with some radio shack parts you can break the mystery of sorts and adjust the drac for gear and tire size mods...the other way you will have to have a ratio box made at a good speedo shop....

DW

[Captkaos]

The donor should have all the parts you need. If basically you are just swapping everything over from one to the other.

[a28doc]

fairly easy to do as long as you go get a tank and fuel lines from a 87 to 91 K5 as they have the return lines and fuel pump you need as far as changing to pw and pdl just grab the wiring from the them and plug them into your harness when you change

Doc

[1FaastC10]

Originally Posted by 1976K5CHALET

Since the 82 had a emissions ecm under the dash you can remount your 7747 ecm in its place....

there's no such thing as an emissions ecm, 1982 was the first year for Electronic Spark Control, which retards timing as it senses detonation, it has absolutely nothing to do with emissions.

[kevinr1970]

Yes it should basicly be swapping from one the the other.

Originally Posted by a28doc

fairly easy to do as long as you go get a tank and fuel lines from a 87 to 91 K5 as they have the return lines and fuel pump you need as far as changing to pw and pdl just grab the wiring from the them and plug them into your harness when you change

Doc

If I were to order the tank in the link above would it include the pump? Any idea on where to buy the fuel lines? If they aren't too expensive I'd rather buy them new as well.

[Captkaos]

I sell replacement tanks for these, but you can use your existing tank. That is what I am doing. If you purchase a tank, it will not come with the fuel sending unit, nor will it come with a pump. GM sells the sending unit (just purchased one) it was $350 my cost. The pump is $60 from NAPA (just bought one also). Classic Tube sells the fuel lines up to the stainless braided section running to the TBI (just ordered those too, not here yet though) they were roughly $300.

If you can find a donor Blazer or someone that is parting one out, it will probably save you some money, but...

[a28doc]

wow I didnt realize they were getting that expensive I was also thinking the sending unit came with the new tanks ty for correcting that Chris... advance auto has sending units for $134.44, fuel pump for 38.88, fuel pump harness connector $11.88, strainer $6.48, can get a brand new steel tank from auto zone for $ 135.99 thats for a 31 gal tank and fuel as far as fuel line goes I think Id prolly find one off a donor or get some fuel line and make my own... pays to shop around sometimes

Doc

[Captkaos]

Doc,
Advance Auto doesn't carry the EFI sending unit, nor does NAPA, at least here they don't, I checked.

I just looked on Advance's website and the only thing they list for $134.44 is the actual fuel tank, no sending unit is listed. I probably could have gotten the pump cheaper, but I get everything from NAPA and it was a Carter pump with a warranty.

[a28doc]

when I looked up an 87 blazer they showed the sending unit there so thats what I posted... I usually buy from napa also due to getting a discount through them but occ get stuff through advanced due to my dad getting a discount there...
Doc