Picked up another one: '87 K2500

[arkracing]

Just picked up another square body. As some of you may have seen my recent thread about what grille to run, well this is the truck.

'87 GMC K2500. Needs some work, but NO RUST in the bed!!!!! that was the main reason I bought it - and the chassis still has the factory black paint on it.

Cab needs drivers floor, corners and rockers. Needs a tranny (I've already located one).

350/TH400/NP208. Has a 10b & 14bsf with 4.10, but I have a D60 & a 14bff with 4.10's that I'm considering swapping in. Only problem I have is that the 14bff I have only has the 11.75" brakes, not the 13.5"

It seems that someone may have put a cam in the TBI motor, because it runs pretty rough, and the computer want's to keep adjusting to keep it running. Seeing that the truck is 8600 GVW I might just swap a carbed motor in. (In Rhode Island anything 8600GVW or greater doesn't have to have emmisions testing ) I have 2 other TBI motors as well, so I'm not sure what I'm doing yet.

I have way to many options on how I want to build this truck - so I'm going to have to write them down and figure out what to do. I do know that I want a stock looking NO LIFT truck.

Anyway pics:

[Stitch]

nice very nice

[rfmaster]

Originally Posted by arkracing

Just picked up another square body. As some of you may have seen my recent thread about what grille to run, well this is the truck.

'87 GMC K2500. Needs some work, but NO RUST in the bed!!!!! that was the main reason I bought it - and the chassis still has the factory black paint on it.

Cab needs drivers floor, corners and rockers. Needs a tranny (I've already located one).

350/TH400/NP208. Has a 10b & 14bsf with 4.10, but I have a D60 & a 14bff with 4.10's that I'm considering swapping in. Only problem I have is that the 14bff I have only has the 11.75" brakes, not the 13.5"

It seems that someone may have put a cam in the TBI motor, because it runs pretty rough, and the computer want's to keep adjusting to keep it running. Seeing that the truck is 8600 GVW I might just swap a carbed motor in. (In Rhode Island anything 8600GVW or greater doesn't have to have emmisions testing ) I have 2 other TBI motors as well, so I'm not sure what I'm doing yet.

I have way to many options on how I want to build this truck - so I'm going to have to write them down and figure out what to do. I do know that I want a stock looking NO LIFT truck.

FWIW I would steer clear of carburetor for this truck. To move this heavy truck (without burning too much fuel) TBI should not be underestimated. The chances are that previous owner just installed 'bottom' of the page cam with a very narrow LSA and overlap designed for high RPM HP operation (great for lighter cars). TBI system needs wider LSA angles 112+ to keep stock tune from going nuts. Keep in mind that stock TBI relies on MAP sensor (engine vacuum) to determine engine load and consequently deliver appropriate amount of fuel. Hence, stock TBI tune does not do very well with large overlap (carburetor based) cams with low idle vacuum. If you can get your engine to idle at about 600-650 RPM with about 16-14 in-Hg ECM will be happy with a stock tune.

//RF

[arkracing]

Originally Posted by rfmaster

FWIW I would steer clear of carburetor for this truck. To move this heavy truck (without burning too much fuel) TBI should not be underestimated. The chances are that previous owner just installed 'bottom' of the page cam with a very narrow LSA and overlap designed for high RPM HP operation (great for lighter cars). TBI system needs wider LSA angles 112+ to keep stock tune from going nuts. Keep in mind that stock TBI relies on MAP sensor (engine vacuum) to determine engine load and consequently deliver appropriate amount of fuel. Hence, stock TBI tune does not do very well with large overlap (carburetor based) cams with low idle vacuum. If you can get your engine to idle at about 600-650 RPM with about 16-14 in-Hg ECM will be happy with a stock tune.

//RF

Thanks for that info. I'm going to play around with the motor and see if I can get it running better before I do anything. I like the TBI in my '94 - I like that you can just start it up without pumping the gas and screwing with chokes etc etc. Big deal here where we have 4 seasons. It just seems to be a little harder to pick decent heads that will run with the TBI system.

I might just put a stock '89 TBI motor in it that I have, and maybe rebuild this one - and then have a computer tuned to match what I do to the motor.

I don't expect to get good gas milage out of this truck. I have a '97 Honda for that. I just need a heavier truck to tow & stop my car trailer. I may even put a plow on it.

[TwoFiftyShifter]

Cool truck. Where in CT are you?

[rfmaster]

Originally Posted by arkracing

Thanks for that info. I'm going to play around with the motor and see if I can get it running better before I do anything. I like the TBI in my '94 - I like that you can just start it up without pumping the gas and screwing with chokes etc etc. Big deal here where we have 4 seasons. It just seems to be a little harder to pick decent heads that will run with the TBI system.

I might just put a stock '89 TBI motor in it that I have, and maybe rebuild this one - and then have a computer tuned to match what I do to the motor.

I don't expect to get good gas milage out of this truck. I have a '97 Honda for that. I just need a heavier truck to tow & stop my car trailer. I may even put a plow on it.

agree on the mileage and the fact that TBI works good over four seasons. We do not have four season here - just warm, dry, very hot and occasional wet and slippery!

From practical point of view just about about any stock (72-76cc) 70's and 80's heads will work with TBI. The major headache that in 86 GM altered intake manifold (4 inner) bolt pattern from traditional 45 to 72 degree. OE TBI intake manifolds requires small amount of effort (slotting four holes) to be adapted to earlier heads. Alternatively you can use pre 86 carb aluminum intake with TBI adapter plate. If the bottom end of that engine is in decent shape a Summit K1101 cam kit will give you performance improvement over stock (OE) cam. To move 8500 lbs you need ample low end torque (1000 to 4000 RPM) so a smaller cam with a free flowing exhaust system should do the trick. Nice truck and project in the making. If you have TBI q's drop a PM.

//RF

[chevymotocross]

Nice find! Me and you both being from Connecticut we know how hard it is to find a truck with the least amount of rust possible! I have an 87 myself with the TBI. TBI was one of the main selling points for me. My previous truck (a f*rd), was carb and was HORRIBLE in the winter. I will never go back! Turn the key and go!

Keep the TBI, try to get it in good running condition. Instead of a swapped cam maybe it's just a pesky vacuum leak or faulty sensor? If not, give a shout out to Brian at tbichips.com. Maybe he can burn you a chip to run with a performance cam (if that's what it has).

[Red_69]

Awesome find! Notice the dome light as an option on the glove box sticker? Nowadays it's rare to see a truck without power windows and locks let alone a dome light. That's a real truck you got there. Have fun with it.

[arkracing]

Originally Posted by TwoFiftyShifter

Cool truck. Where in CT are you?

I live in Manchester (about 10 min east of Hartford). I actually found the truck in RI. I still have a dual residency thing going on, so I register all my stuff in RI.

Originally Posted by chevymotocross

Nice find! Me and you both being from Connecticut we know how hard it is to find a truck with the least amount of rust possible! I have an 87 myself with the TBI. TBI was one of the main selling points for me. My previous truck (a f*rd), was carb and was HORRIBLE in the winter. I will never go back! Turn the key and go!

Keep the TBI, try to get it in good running condition. Instead of a swapped cam maybe it's just a pesky vacuum leak or faulty sensor? If not, give a shout out to Brian at tbichips.com. Maybe he can burn you a chip to run with a performance cam (if that's what it has).

Yeh it's in very good shape for a new england truck - I guess it originally came from South Carolina. It's been up here about 10 years hence the floor/rocker rot. I still can't believe how nice the Frame & Bed are, even the doors are nice. There are quite a few dents in it, but I think I can save the original doors. The front clip will be changed.

I was looking at the truck a little closer and found a few interesting facts -

#1. It appears that it was originally a service vehicle for a company called "Bay Peterbilt" - I googled it, but didn't find one on Pete's dealership listings.

#2. It had a on-board engine driven air compressor. It is no longer on the truck, but I sure would have liked to see it. There was a big plate on the passenger side of the motor to mount the pump to. There was a tank in the bed and they cut about a 1" hole in the bed floor for the air line. There is also some type of idle control - I would assume to idle up the motor when the compressor pump kicked in.


I'm going to stay with the TBI, but I'm pretty sure there is a cam in the motor that needs to be addressed. The guy that I bought it from said that his father used the truck and changed the motor about 85k ago. He also said "my father was a hot rodder and put dual exh with glass packs on the truck" which is why I think there might be a cam in this thing.

Anyway here is a pic of the motor: (I have a short video of it running, if I can figure out how to post it, so you guys can see if you agree about the cam or maybe something else)






Think I got it - not sure if you can hear it that well though. (The whine noise is the tranny - I believe the pump is blown, no forward or reverse)

You Tube

[86454k30]

I just bought the same exact truck a month ago. Except mine doesn't have cab lights and is a 4 sp.