After I figured out the factory block was junk it was time to get it out of there.
Got the Block out and … a little while later, I had the tranny out as well. I then borrowed a bare block, head and manifolds for the mock up process. Since so little was online about this swap, I thought it was best to make sure it would all fit before I was to committed to swapping in a SBC. It’s also easier to work with.
I pretty much let it hang there while I added the head, manifold, radiator and accessories to make sure everything would fit. Only issue at this stage was the distributor. GM HEI distributors are huge if you hadn’t noticed. I already had a plan for that issue.
Next I found some universal motor mounts at Speedway. If it works for dirt cars, it seems to be fine on street cars.
While this was going on I was also working on getting an engine together. Wife was a big help. She got right out there and got dirty.
I already mentioned the 350 was junk so I moved on to a 327. Turns out it needed a new cranks shaft. This held the build up for a few weeks and added $480 to the cost. Not fun at all but I was tired of looking for engines.
My 327 after sandblasting and paint. Yes that is a normal Edelbrock intake. I painted it red to look stock. My goal for this swap was to be done inexpensively and for it to look like it could have been factory.
Take note of that oil pan. During mockup I used a flat steal pan that is stock on pretty much any SBC. Well… the main cross member was in the way of the drain plug. My plan was to get a pan with a rear drain plug. No biggy. Issue was that rear mount pans are all aluminum and fancy. This one had these fins on the bottom of it. It didn’t actually fit anymore. Of course I did not notice till the engine and tranny was bolted down and it cracked the oil pan. I had to remove the cross member and grind those pretty fins off. I then used JB Weld to patch the crack. I know, I know… but its a $250 Mazda, the JB Weld will be fine.
Engine is in, power steering is in. This picture has a great shot of the solution for power steering. I took the GM high pressure line and the Mazda high pressure line to a hydraulic shop (local Carquest). The owner was able to simply cut each line and then join them together with a union. As of now, its working great.
The next big issue turned out to be the alternator. I spent way to much money messing with this. The alternator was lined up perfectly with the upper radiator hose mount. Thus, making it impossible to hook up the radiator.
I tried several different mounts and ended up getting a Mark right side mount. Of course my heads were not drilled for this and I ended up breaking two snap-on taps trying to drill them out. I had to put a stud on one side and JB Weld it on the inside of the head to make sure it didn’t leak any water. This has been the biggest and most expensive issue in the build. Good news is I finally got it working.
The solution for the distributor was that little box you see on the fender well. MSD makes a Street Fire kit that comes with everything you need for around $250. It was an easy install. Just need to hook up the coil and the box. Full time power, key power and ground. It even has a built-in adjustable rev limiter. Take note… there is no vacuum advance. It’s a mechanical advance that increases the timing 10 degrees. This gave me issues early on. Base timing is now at 21 degrees and its running great.
For a carb, I tried a 750 Holley that I had sitting around. Of course as I already knew, it was way to big. I changed that out for a 570 Street Avenger. I only do Holley. Years ago, I decided to learn Holley’s and have no desire to deal with any other carbs.
Cam break-in was a disaster. The engine kept over heating. Im afraid I may have to replace the cam soon since I didn’t get it to run for 20 min. Take note that a 2 core radiator won’t cool a 327. I have no idea how it cooled a 307. I also had issues getting the air out of the system. The radiator is slightly lower then the engine. This would not let me get the air out. I ended up jacking the passenger side of the truck up so the radiator fill spout was higher and then let the truck run with no cap on it. I just stuck a running hose in there to get through the cam break-in. Once I was done, I drained it and filled with coolant and bottled water. Engine kept over heating until I finally changed the radiator. It now has an aluminum 4 core. Took a lot more cutting than I wanted but it does fit.
At this point he is running but not driving. Waiting on the drive line. Time to get him on the ground. As you can see, the weight of the engine dropped it a far amount in the front. That will help with alignment later on.
Still doesn’t look much like a minitruck but it will soon.