I bought me a 1986 305tpi and 700r4 out of a camaro with the wiring harness and computer afew months ago and now am ready to drop it in my blazer Im building, so I have a few questions.
1. Im trying to use the whole camaro wiring harness and computer in my blazer but I didnt get an interior wiring harness, so I was wondering what other years harness would work? What gauge cluster can I use(does it have to be the 305? Does the year difference matter?).
2. My underhood harness doesnt have the fuel pump wiring and was wondering where that goes? (Is it part of the interior harness? Is there a seperate harness that goes back there?)
3.I have a '73 350 sitting in my garage for a while. Would I be ok running the tpi sysem and computer on the 350? Any issues I would run into?
I appretiate any help you can give me.
Thanks,
Chris

 

Nothing from the computer connects to the gauges so you can keep your original gauges and wiring to them if you want

Should be part of underhood harness typically on the firewall by the brake booster
See
https://www.thirdgen.org/forums/post...170-post4.html

All you need is the chip ( tune ) for a 350 in the computer you have and 350 injectors .350 are 22lb vs 19 lb for 305

The 305/350 use same # '165 computer; only the the programming is different

 

I dont know if I can do that since the gauge cluster in my truck is ran by the computer(its an 02 blazer), but I will look into that.


I see that but I dont have a harness that goes back there, so Im confused where the wiring to the pump itself is?

The computer has a superchips chip in it, so would that work for me?
Thanks again.

 

Maybe aftermarket gauges run off their own sensors as a simpler option ?

If you have a complete TPI engine harness back to the firewall connector then it should be in the location noted
As far as the interior harness goes you need at least from the firewall connector to the computer
Don't know how you are placed $ wise but a aftermarket standalone engine harness would simplify your install;
everything from computer to ECM inc relays for pump and MAF.
3 wire hookup ;batt / Ign and fuel pump ( + grounds )

http://www.ebay.com/itm/TPI-Mass-Air...item20c1666291

 

I have the harness all the way to the computer and I got where the relay for it is but Im wondering where the wiring directly to the pump is because my harness doesnt go that far back.
And thats alittle much for me, when I already have the harness and computer.
Thanks,
Chris

 

Follow the output wire from the pump relay you have to it's end and join to it

 

You my friend are in for an awful lot of work for very little gain.

 

blazin97 I see you have come over from s10 forums in your knowledge quest. Iircc, there are five major thirdgen harnesses (excluding "Bose" stereo, battery cables).

(1) fuel pump harness, runs from fuel sender to rear floor pans (under rear seat, trans tunnel).

(2) interior harness runs from fuel pump harness, spiders through interior (includes fuse box, gauges, fuel circuit) connects at c100 at drivers firewall. Note: c100 splits into two harnesses firewall forward, for this we will label these as harness (3),(4).

(3) headlight harness, from c100 to headlights.

(4) c100 engine harness, from c100 to engine and accesories (brakes, wipers, ect)

(5)c207? I belive this is the harness you have. Runs from computer through pass kick panel to engine.

Some one correct me if I got something wrong and I will edit.

 

Yah I didnt get much help over there and I figured more people would know here. Thanks

I have (3), (4) and (5). Thanks for the help. Does the interior harness differ between the years or are they all the same? Is there a difference in the gauge clusters?
Thanks

 

you could build a harness and run the 411 pcm and a express van cal and probably keep your stock gauges........You probably already have the 411 pcm in the blazer just would need to reprogram it and repin it and add a few more wires

 

No Im good without all that hastel. I think Im going to just use the camaro engine harness, computer and gauges, then everything else is going to be the blazer(headlights, taillights, windows, locks, etc.).
Now I just have to figure out if I can use a gauge cluster from a 90 camaro with a 2.8 and have averything work right, does anyone know?
Thanks

 

Why are you going though all the hassle to change the gauges? Use the Blazer panel. just tag the wires that presently go to the sensors and use the Blazer sensors in the Camaro engine. You are only talking oil pressure and temp and the voltmeter right. The other TPI sensor stuff goes to ECM not gauges or am I missing something?

 

the blazer he has gets it cluster info from the datalink from the pcm. I have ran tpi on the 165 ecm, then went to the sd ecm, and now to the 411. You want to make this a simple swap use the 411 and keep the blazer cluster. trust me. Alot less work. if you use a cluster out of a camaro your either going to have to change out the tank level sensor. its a pain in the ***. to use the pcm already in your blazer you reflash it put a vortec dist in the engine and the vortec crank reluctor and timing cover. and repin the ecm connector and add a few wires. trust me its easier then you think this way.

 

What do you mean by 411ecm? Can I get some more info on this? It sounds like the best option for me and I think it would be sweet to have the 02 blazer cluster.

 

Still think it's a lot of work for very little gain.

 

read here

https://www.thirdgen.org/forums/tpi/...-opinions.html

Also, are you running a 4l60e in the blazer now? If you are you could keep the tranny also. If you got a manual then you could use the older ecm but the driveabilty of a 411 is awesome and being able tune the tranny is nice. If I was doing your swap after doing all the tpi on my 98 pickup I would go the 411 in a heart beat

 

It was a factory 5spd truck but when I got it there was no drivetrain in it. I plan on running the 700r4 from the camaro since I got it with the 305 and computer.
I've spent the last 8 months putting air ride on it and now its down to puttin the motor in and get her on the road. FINALY

 

Just giving you what i have goon though and is my opionon. Best of luck. any questions just pm me

 

What is the difference? I have a fuel cell anyway but it still has the 0-90 Ohm sending unit and I was told the camaros were the same.
I just read threw the thread about the 411 computer, and it seams like alot more work than I wanna do to this truck. So I think im still going to use the camaro cluster, but I still have to figure out if there is a difference between a 86 305 gauge cluster and a 90 2.8 cluster

 

what is the ac heater power connect?