amsterdam96
OBS Enthusiast
DISCLAIMER: I've previously stated the truck came with a 502 Ram-Jet. This was a newbie mistake of me and it's an Accel DFI not a Ram-Jet. Note however that this Accel is also called/labeled "RAM" which is what caused the confusion to begin with.
So to begin my build thread I'd like to clarify that I more or less stumbled upon this truck. Prior to owning this truck I had no experience actually working on cars, despite having been interested in automotive engineering for most of my teenage-years.
I had to figure out what I was looking at as I went along. I tried to get the car running and moving to the best of my ability, simultaneously trying to 'google before breaking' things.
I got the engine running after helping it out with a little starter fluid and gently feeding it gas by pressing the pedal seeing as she wouldn't idle by herself. I figured out how the low-gear box selector works (more or less) and put the car into 'drive & 2HI' then later 'drive & 4LO'. The truck rolled into motion it'd only crawl/limp at about 2-5 MPH. When having to drive up small but steady slopes she refuses. There was a clear lack of power at the wheels.
My conclusion is that the transmission is severely damaged. I'd read a 4L60 diagnostic sheet and this mentioned a forward-sprag. The symptoms of this common failure sounded similar to mine. I overlooked the fact that the transmission in my truck is a 4L80e instead. I believe these transmissions don't have a forward sprag. But I imagine the failure is somewhat similar. It seems as if the transmission works to a certain extent allowing the car to roll when powered but lacking any serious torque/drive to the wheels.
Besides the serious drive-train issue. (Which I believe I can tend to myself, with the aid of a video-tutorial I still have to buy).
There's the issue that the ECM is proving to be. The truck has a PROM type ECM/Digital Fuel Injection Module that dates back to '87 various technicians I've spoken to. I've also contacted individuals that still service older EFI's but nobody seems to be familiar with Accel DFI's from the 80's (No surprise ).
I was also told that I'd need a 386 type computer (A computer from the 80's) to run the diagnostic software that's compatible with this ECM. Considering the rarity of mint micro-computers from the 80'ies and the unlikely chance that i'll find the software needed for the diagnosis, I concluded I'm going to have to buy a new ECM.
My supercharger however is in fine condition, so it's an utter shame to dispose of it simply because the ECM is outdated/ no longer supported.
People have suggested Holley EFI's for 502's. Does anyone know of a 502/ 8.0l V8 ECM. I've considered swapping out the 'Super' for a Carb but I have no experience with American cars and I'm not sure how well this would merge with the electronics that regulate the rest of the car.
To make matters more complicated, the car seems to have previously had Dry Sump Oil system installed. The only remnants that I can spot of this 'fancy' piece of tech is one aftermarket oil-canister & a scavenge-pump. The large Oil Tank (not the one under the car, but the one under the hood) along with the main Oil Tank have been removed (Presumably the previous owner took them off because they're worth a considerable amount)
Below you'll find some pictures that I took: I've marked some 'mystery-wires' with purple & silver tape. If you have any input on any of the photos, it'd be much appreciated! Thank you all for showing an interest!
So to begin my build thread I'd like to clarify that I more or less stumbled upon this truck. Prior to owning this truck I had no experience actually working on cars, despite having been interested in automotive engineering for most of my teenage-years.
I had to figure out what I was looking at as I went along. I tried to get the car running and moving to the best of my ability, simultaneously trying to 'google before breaking' things.
I got the engine running after helping it out with a little starter fluid and gently feeding it gas by pressing the pedal seeing as she wouldn't idle by herself. I figured out how the low-gear box selector works (more or less) and put the car into 'drive & 2HI' then later 'drive & 4LO'. The truck rolled into motion it'd only crawl/limp at about 2-5 MPH. When having to drive up small but steady slopes she refuses. There was a clear lack of power at the wheels.
My conclusion is that the transmission is severely damaged. I'd read a 4L60 diagnostic sheet and this mentioned a forward-sprag. The symptoms of this common failure sounded similar to mine. I overlooked the fact that the transmission in my truck is a 4L80e instead. I believe these transmissions don't have a forward sprag. But I imagine the failure is somewhat similar. It seems as if the transmission works to a certain extent allowing the car to roll when powered but lacking any serious torque/drive to the wheels.
Besides the serious drive-train issue. (Which I believe I can tend to myself, with the aid of a video-tutorial I still have to buy).
There's the issue that the ECM is proving to be. The truck has a PROM type ECM/Digital Fuel Injection Module that dates back to '87 various technicians I've spoken to. I've also contacted individuals that still service older EFI's but nobody seems to be familiar with Accel DFI's from the 80's (No surprise ).
I was also told that I'd need a 386 type computer (A computer from the 80's) to run the diagnostic software that's compatible with this ECM. Considering the rarity of mint micro-computers from the 80'ies and the unlikely chance that i'll find the software needed for the diagnosis, I concluded I'm going to have to buy a new ECM.
My supercharger however is in fine condition, so it's an utter shame to dispose of it simply because the ECM is outdated/ no longer supported.
People have suggested Holley EFI's for 502's. Does anyone know of a 502/ 8.0l V8 ECM. I've considered swapping out the 'Super' for a Carb but I have no experience with American cars and I'm not sure how well this would merge with the electronics that regulate the rest of the car.
To make matters more complicated, the car seems to have previously had Dry Sump Oil system installed. The only remnants that I can spot of this 'fancy' piece of tech is one aftermarket oil-canister & a scavenge-pump. The large Oil Tank (not the one under the car, but the one under the hood) along with the main Oil Tank have been removed (Presumably the previous owner took them off because they're worth a considerable amount)
Below you'll find some pictures that I took: I've marked some 'mystery-wires' with purple & silver tape. If you have any input on any of the photos, it'd be much appreciated! Thank you all for showing an interest!
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