Another Mopar Off My Bucket List - Barracuda Fastback
Unfortunately I seem to have misplaced (lost) a lot of the photos I did take of progress made over the past few months. One thing I did work on again was Spence's '70 Roadrunner. It's been running good since he got it back from that last tuning shop he'd gone to. Because he's used it as a daily driver he hasn't focused on getting any of the needed bodywork done. Instead he's just wanted to tweak the drivetrain and eliminate any issues it might have.
As I've mentioned in the past, he's been running Evans Waterless coolant and it seems to have been a good choice so far. Once you stop worrying about the extra 10' to 20' temperature rise over standard antifreeze mixes you get used to seeing the temp hover around 200' all the time. When he was driving the car this summer in slow, heavy traffic he started to become concerned because the temp was getting closer to 220'.
After I inspected the car I figured his problem was likely from lack of airflow through the radiator. He's been running a 4 core Champion with no shroud and the mechanical fan sat about 4" away from the radiator. At low speed there was no way it could pull air across the cooling fins. The temperature was always acceptable going down the highway.
I told Spence that I'd solve his problem for his birthday so I made a trip to Des Moines, loaded it up and brought it back home with me.
I started by using a wider spacer to move the fan closer to the radiator. I figured a 3/4" gap looked about right. Then I wanted to fabricate an aluminum shroud for it next but the fan that he was using was so large in diameter that it overhung the right side by almost 2" and extended to the top of the radiator tank. It would have been very difficult to make a shroud to fit properly without swapping out the fan for a smaller diameter so I decided to use the stainless steel flex fan that I originally ran on my Barracuda. I think it was a 16" fan and his had been an 18".
Everything was coming together perfectly. I was able to make a shroud that fit great. The Champion radiator has a flange on the side towards the motor that was a good attachment location and I installed some nutserts in it so that it bolted up with 4 fasteners - EZ PEAZY.
I got it done and it seemed to pull air through the radiator 10X better than ever. I even gave it a quick polish before installing.
After idling for a few minutes in the driveway it was time to take the car for a drive and see how the coolant temperature responded. That's when disaster struck. :BangHead:
Despite the fact I thought I had sufficient clearance, I didn't count on how much effort it took those fan blades to pull air through a 4 core radiator. They apparently flexed towards the radiator as engine speed increased. Even though the engine was only running at about 2000 rpm, it must have drawn those blades in too far and I shredded his radiator. The engine is mounted firmly and doesn't have much rock to it so I'm fairly sure it was the suction that caused the contact.
I had been eager to call Spence to let him know I'd finished his car before I screwed up. Now I had to call him to let him know otherwise.
It was discouraging but I knew I had to fix the mess I made. The new shroud I'd fabricated survived unscathed but the fan and radiator were toast. After researching options online I decided to buy a new radiator combined with a pair of electric fans and a matching shroud. It wasn't much more than the cost of going back to another mechanical fan and Spencer had once mentioned that he thought he'd like to gain whatever horsepower back that the mechanical fan drew.
I think he'll be happy with this setup. For now I simply drew the power directly off the battery and through a toggle inside the car. No relays or fuses yet. If everything works well I'll most likely go back and re-do the way I wired it.
One other issue the Roadrunner had was that the steering wheel wasn't clocked correctly. Spencer had replaced the original (leaking) steering box with a new one from Borgeson. When he did he also decided to upgrade the stock steering coupler to a universal joint. He hadn't taken the time to align the steering wheel when he swapped the parts out so I went ahead and re-did it for him.
I'll be hauling his car back to him later this week. I'm hoping the wind settles down before then.
Unfortunately I seem to have misplaced (lost) a lot of the photos I did take of progress made over the past few months. One thing I did work on again was Spence's '70 Roadrunner. It's been running good since he got it back from that last tuning shop he'd gone to. Because he's used it as a daily driver he hasn't focused on getting any of the needed bodywork done. Instead he's just wanted to tweak the drivetrain and eliminate any issues it might have.
As I've mentioned in the past, he's been running Evans Waterless coolant and it seems to have been a good choice so far. Once you stop worrying about the extra 10' to 20' temperature rise over standard antifreeze mixes you get used to seeing the temp hover around 200' all the time. When he was driving the car this summer in slow, heavy traffic he started to become concerned because the temp was getting closer to 220'.
After I inspected the car I figured his problem was likely from lack of airflow through the radiator. He's been running a 4 core Champion with no shroud and the mechanical fan sat about 4" away from the radiator. At low speed there was no way it could pull air across the cooling fins. The temperature was always acceptable going down the highway.
I told Spence that I'd solve his problem for his birthday so I made a trip to Des Moines, loaded it up and brought it back home with me.
I started by using a wider spacer to move the fan closer to the radiator. I figured a 3/4" gap looked about right. Then I wanted to fabricate an aluminum shroud for it next but the fan that he was using was so large in diameter that it overhung the right side by almost 2" and extended to the top of the radiator tank. It would have been very difficult to make a shroud to fit properly without swapping out the fan for a smaller diameter so I decided to use the stainless steel flex fan that I originally ran on my Barracuda. I think it was a 16" fan and his had been an 18".
Everything was coming together perfectly. I was able to make a shroud that fit great. The Champion radiator has a flange on the side towards the motor that was a good attachment location and I installed some nutserts in it so that it bolted up with 4 fasteners - EZ PEAZY.
I got it done and it seemed to pull air through the radiator 10X better than ever. I even gave it a quick polish before installing.
After idling for a few minutes in the driveway it was time to take the car for a drive and see how the coolant temperature responded. That's when disaster struck. :BangHead:
Despite the fact I thought I had sufficient clearance, I didn't count on how much effort it took those fan blades to pull air through a 4 core radiator. They apparently flexed towards the radiator as engine speed increased. Even though the engine was only running at about 2000 rpm, it must have drawn those blades in too far and I shredded his radiator. The engine is mounted firmly and doesn't have much rock to it so I'm fairly sure it was the suction that caused the contact.
I had been eager to call Spence to let him know I'd finished his car before I screwed up. Now I had to call him to let him know otherwise.
It was discouraging but I knew I had to fix the mess I made. The new shroud I'd fabricated survived unscathed but the fan and radiator were toast. After researching options online I decided to buy a new radiator combined with a pair of electric fans and a matching shroud. It wasn't much more than the cost of going back to another mechanical fan and Spencer had once mentioned that he thought he'd like to gain whatever horsepower back that the mechanical fan drew.
I think he'll be happy with this setup. For now I simply drew the power directly off the battery and through a toggle inside the car. No relays or fuses yet. If everything works well I'll most likely go back and re-do the way I wired it.
One other issue the Roadrunner had was that the steering wheel wasn't clocked correctly. Spencer had replaced the original (leaking) steering box with a new one from Borgeson. When he did he also decided to upgrade the stock steering coupler to a universal joint. He hadn't taken the time to align the steering wheel when he swapped the parts out so I went ahead and re-did it for him.
I'll be hauling his car back to him later this week. I'm hoping the wind settles down before then.
