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Old 01-30-2012, 08:25 AM   #1
BigBlocksRule
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TBI swap scavenging list - experts inside, please

I have an '86 single cab dually that I intend to use for a work truck until the wheels fall off. I'm swapping out the tired 454 and TH400 (both have been farm worked pretty hard) in favor of a fresh Gen 6 454 and 4L80E. A buddy is parting out an '87 longbed with a 305 in it. I've already snagged both saddle tanks with brackets, plumbing and switch/valve from that truck. My '86 was equipped with saddle tanks, so I'm hoping all the bolts for tanks, valve, etc. lines up. Next step is wiring and switch. How hard is it to follow these wires through the firewall and to the switch? I assume I'll have to locate a main power and ground wires, but are the rest of the wires pretty much bundled together?
My computer and wiring harness are from a '95 as is the 4L80E. Engine is out of that truck, so it will be much easier to scavenge the computer and wires. I'm counting on the guys at 454SS to help with chip/tune. Engine will have a 214/221 hydraulic roller cam which was recommended by Crane for good fuel economy and towing power. It's a bit more of a cam than the old "RV" cams we used to use, but I've been assured it's computer friendly.

While I have the donor truck handy, what else will I need for this conversion? I'd been thinking about doing it for awhile because I except for poor mileage from a tired engine and non-overdrive tranny, I really like the old single cab dually, but hung a stump when it came to pumps in tank and getting the wiring and valves to work for tank switching. Since the donor truck popped up, I decided to grab everything I could or would need off if it rather than having it all crushed.

Thanks in advance for the help!!!
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Old 01-30-2012, 10:42 AM   #2
Jonboy
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Re: TBI swap scavenging list - experts inside, please

FWIW, I used a new aftermarket harness when I did my TBI swap. I figured it was worth the money in headaches not having to deal with 25 year old wiring and connectors. I bought mine from fuel injection connection (www.fuelinjectionconnection), and the hookup was pretty easy. I know Robert makes one to control the later model electronic transmissions, too.

Make sure you get (or have) a Park/neutral switch (part of the neutral safety switch on the '87), and a brake switch for cruise control (will have 2 sets of contacts).
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Old 01-30-2012, 05:45 PM   #3
rfmaster
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Re: TBI swap scavenging list - experts inside, please

Quote:
Originally Posted by BigBlocksRule View Post
I have an '86 single cab dually that I intend to use for a work truck until the wheels fall off. I'm swapping out the tired 454 and TH400 (both have been farm worked pretty hard) in favor of a fresh Gen 6 454 and 4L80E. A buddy is parting out an '87 longbed with a 305 in it. I've already snagged both saddle tanks with brackets, plumbing and switch/valve from that truck. My '86 was equipped with saddle tanks, so I'm hoping all the bolts for tanks, valve, etc. lines up. Next step is wiring and switch. How hard is it to follow these wires through the firewall and to the switch? I assume I'll have to locate a main power and ground wires, but are the rest of the wires pretty much bundled together?
My computer and wiring harness are from a '95 as is the 4L80E. Engine is out of that truck, so it will be much easier to scavenge the computer and wires. I'm counting on the guys at 454SS to help with chip/tune. Engine will have a 214/221 hydraulic roller cam which was recommended by Crane for good fuel economy and towing power. It's a bit more of a cam than the old "RV" cams we used to use, but I've been assured it's computer friendly.

While I have the donor truck handy, what else will I need for this conversion? I'd been thinking about doing it for awhile because I except for poor mileage from a tired engine and non-overdrive tranny, I really like the old single cab dually, but hung a stump when it came to pumps in tank and getting the wiring and valves to work for tank switching. Since the donor truck popped up, I decided to grab everything I could or would need off if it rather than having it all crushed.

Thanks in advance for the help!!!
The '95 PCM ('427) can handle most RV style camshafts - so do not go too crazy with duration. The crane cam mentioned is perfect and PCM should be able to adapt its baseline fueling tables (VE) without too much bother. The 95 PCM uses 4000 ppm VSS - you need to grab DRAC module from 95 donor, also make sure that VSS is bolted into the tail shaft. The problem that you'll run in is that 86 uses mechanical spedo and 95 has electronic. There are couple ways to go about this.
//RF
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Old 01-30-2012, 08:58 PM   #4
BigBlocksRule
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Re: TBI swap scavenging list - experts inside, please

I snagged a '93 Suburban electronic gauge cluster, will need help adding tach and moving gas gauge. I own the '95, it will be prostreeted so the TBI wiring harness...and pretty much anything else I need...is available. Sensors are still in the tranny. This is a budget deal, building from parts scavenged from other parted out trucks including the machined, ready to assemble fresh .040 over 454 with big valve closed chamber 396 heads and the aforementioned valvetrain. I still need to nail down an intake manifold, I have a couple of 454 throttle bodies to choose from and will rebuild the better of the two.
I can't swing the money for a custom wiring harness, the one I have is in very good condition. Who could I send it to that could add the correct 454 specific sensor plugs and give me a 12V in and Ground lead?
Thanks for the help, I think this can be a great sleeper (truck has been named Fugg Lee, will have lettering on the sides) that will make a great work truck and tow rig and if tuned right, should knock down some decent mileage in spite of it's size. And I can simply turn the key and fire it up any time I want to.
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Old 01-31-2012, 08:40 AM   #5
BigBlocksRule
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Re: TBI swap scavenging list - experts inside, please

Alright, the donor for the tanks, etc. is off to the scrap yard in a couple of days. Is there anything else I need from this truck?
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