Reviving An Engine (A Really Old Engine)
February 1, 2002
By Scott Lewis
Unless you have been reading this column since its inception you probably don't know that I still have a Chevy 350 engine in storage that could be used for a project car.
I have mentioned in more recent articles my desire to buy a new car or get a classic Camaro, Mustang or Corvette. However, there is one possibility I have not mentioned in a long time. I could build a project car with that 350 engine. This would be a project I would expect to sell to fund the afore mentioned Camaro, Mustang or Corvette.
In a previous column I mentioned the possible cars I would put that engine in. I may revisit that topic in the future, especially if this possibility looks promising. But this month I wanted to talk about what that engine would need to make it road worthy. You should note that it has been in storage for over a dozen years, so there are some special requirements to get an engine running after such a long sabbatical from life.
I originally built this engine in 1986. I was working in a gas station, pumping gas to get through college. I saved my step-brother by buying a 1970 Chevelle off him that was in horrible condition. The body was sound, so I figured I could handle the rest myself. That car had a 307 engine with a 2 speed Powerglide automatic transmission. I only paid $500 for the car. (My step-brother paid $800. Like I said... I saved him from the money pit the car was destined to be.)
When I removed the barely running engine I found three piston skirts in the oil pan. When I removed one of the pistons the ring lands fell out in my hands. The piston was completely ruined. It was amazing the car ran at all. It did leave a cool, blue smoke trail for a good 400 to 500 yards.
My mechanic at the time (my best friend's step dad) had a 350 four bolt main short block he was willing to sell. $75 later I had that short block in my garage on an engine stand. I stripped the 350 short block down in preparation for machine work. I did a little research to determine it had a forged steel crankshaft, preferable to a cast iron crank for performance. I ordered the parts to build up what I was dreaming would be a nice 400 horsepower small block. I ordered 11:1 domed, forged pistons & molly rings. I ordered a Holley Dominator intake manifold. It was a high rise dual plane design similar to the one on the original 1970 LT-1 Camaro. That engine was good for 360 horsepower. The Holley manifold was supposed to be an improvement on the original LT-1 design. I paired that up with a Holley 700 double pumper four barrel carburetor. I figured that would easily feed a 350 running at 6500 RPM. The final piece was a Crane camshaft. This many years later I really can't remember the specs on that cam, but I know it would have been a good match for the other parts.
Some of the parts were put on backorder. I wasn't in a hurry so it didn't matter. As soon as the pistons arrived I took the block, crank, rods & pistons (old and new) to the machine shop. I had the block hot tanked and cleaned, all the threads tapped, cam bearings and freeze plugs installed, the deck resurfaced (it had some surface rust, so I didn't even ask if it was straight), bored .030 over, honed with torque plates to match the pistons, rods rebuilt with high strength aftermarket connecting rod bolts, pistons pressed on the rods, and the crank turned .010 under and polished.
I can still remember the day I picked up the parts up from the machine shop. It cost me $610 for all the machine work. When I got home there was a message to call work before going in the next day. I was fired. I should have seen it coming, but I was too naive. The gas station I worked at was sold about a month before and the new owner fired all but two of the original employees. That weekend the two of us were out of a job.
Now I had a freshly machined short block and no job. Oops!
I had not made up my mind yet on what cylinder heads I was going to buy for this engine. Now I couldn't afford heads. I called up about the intake manifold, carburetor and camshaft on backorder. As luck would have it they were still on backorder. Since I still needed to put this engine together I didn't cancel the order, I changed it. I changed the order to an Edelbrock Performer intake manifold and matching Edelbrock Performer camshaft, and changed the 700 double pumper to a 600 CFM vacuum secondary Holley carburetor.
As for the heads... I still had the heads from the 307. My mechanic knew a place I could get a set of reconditioned (remanufactured) heads for a good price on an exchange basis. It cost me $125 for the reconditioned 307 heads. I was now planning on building a mild manner small block due to circumstances beyond my control.
I ended up spending the entire winter assembling that engine. I had no money and had another car to drive, so I was in no hurry. I finished that car up about 3 months before moving to Texas. The powerglide died after about a month on the road, so I swapped in a junkyard Turbo 350 transmission.
After driving the car for almost a year, I decided it was time to put the horsepower in it that I originally wanted. I found a set of early fuelie cylinder heads at a speed shop being sold on consignment. They were 425 bucks ready to run. I thought it was a bargain. I had been following the aftermarket and this seemed like a good deal. The heads were equipped with 2.02 stainless steel intake valves, but only had 1.5 non-stainless exhaust valves. Since I did not have a lot of money I figured this was good enough.
As it turned out I should have held out for a few more months. World Products introduced their Dart heads at $825 a pair complete with 2.02 & 1.60 stainless steel intake & exhaust valves, respectively. The Dart heads would have flowed much better and would have been much easier overall. 20/20 hindsight, oh well.
I bought a Competition Cams 280 Magnum cam. This cam was a little on the big side so I paired it with Crane's High Intensity lifters. These were supposed to bleed down during low RPM to make the cam "seem" smaller at low revs and pump up to full lift at higher RPMs.
I also installed hardened pushrods, necessary with the guide plates on the cylinder heads, and Competition Cams Magnum roller tipped rocker arms.
Since this would increase breathing in the engine I also swapped the Edelbrock Performer manifold for one of their Torquer II manifolds. The Torquer series were single plane manifolds that were designed for higher RPMs than the low profile Performer. The Torquer II was a new low profile manifold that was supposed to provide better low RPM torque for a single plane manifold. I figured this would work good with the High Intensity lifters, also designed to help low RPM torque, and the fact that I still had the 600 Holley.
With all that installed the engine kept back firing. I called my mechanic (he is still in New York, even though I am now in Texas) to get some help. When I told him all the parts I added he immediately asked what carb I was using. When I told him I was still using the 600 Holley he told me to get a bigger carb, I was starving the engine. I didn't have any money left. He told me I could richen the carburetor's jetting as a "band-aid" until I could afford a bigger carb. Sure enough 4 steps up in jet size worked like a charm.
The engine ran for a while. I never got all the bugs worked out. The compression on the engine was so high it was hard to crank. The fuelie heads had the smaller 64 cc combustion chambers. I needed a bigger battery, and better starter. Also I was having a problem getting the timing just right. I blame this on having an old junkyard HEI distributor that was sorely in need of a rebuild. And I never got around to getting the bigger carburetor.
I drove the car with those bugs for a couple of months. Then the transmission failed. I still didn't have any money. At this point I was in need of more reliable transportation, so I took out a small loan to buy a Toyota Celica and parked the Chevelle. The Chevelle got more and more forgotten about. Either I didn't have the time or the money to fix it right. Since I didn't have much money invested in the car itself I decided to pull the engine and get rid of the car. A guy I knew asked if he could have the car. I told him he could have it for free... if he showed up the day I pulled the engine with his own wheels. The wheels on the car were American Racing aluminum wheels with Goodyear Eagle ST tires. They cost me $500 back in New York, so they were worth it to me to save them.
Round Three - The Revival
That brings us to today. I probably had about $2,500 in that engine between the two stages of development. But that is $2,500 that I spent between 1986 and 1988. Long ago I wrote that investment off. But I still have the engine. So what would it take to get it running, and use it in a car again.
I soaked the cylinders with plenty of oil before storing that engine. But it sat in the car un-prepped for a few years. It is likely that the engine will not be in great shape when I open it up. But I can make some assumptions for this article.
First, I will hope that the cylinders, pistons, crank, and rods are all in good shape. Worse case here would be that the cylinders need a mild honing to clean them up and a new set of rings. I would replace the crank and rod bearings too. This is pretty cheap insurance.
Next I would have to address the cylinder heads. They were no prize as I learned later. So I would look to get a set of aftermarket heads. I would try to get aluminum since they are more tolerant of high compression ratios. Also, I would look for heads with 76 cc combustion cambers. That would lower the compression ratio about one point to 10:1. The 11:1 compression with the 64 cc heads was just too much to run on 91-93 octane gasoline, as I learned the hard way. Even if I tried to keep those cylinder heads I would have problems. I had to have a hole drilled and tapped into them to accept the alternator bracket. Those heads were an early design that didn't have provisions for later accessories. Also, after sitting in place for about 13 years, half the valve springs would be shot due to being compressed for so long. Finally, I would have to have the heads machined for the larger 1.6 stainless steel exhaust valves, as well as buy the valves. I could get a set a Vortec heads cheaper than it would be to update the old fuelie heads. (BTW, the reason they called them fuelie heads is because that design was used on the early mechanical fuel injected engines in Corvettes during the sixties.)
Edelbrock and Holley each make a nice set of aluminum cylinder heads for the small block Chevy. I would also see what AFR & World Products is up to nowadays. Any of them would be able to satisfy my needs. Cost would probably be a major factor in picking a set of new heads. I would want to stay below $1000. Also, I would prefer aluminum because of its tolerence to high compression ratios. I would still look for open chamber (70 - 76cc) heads to try and bring the compression ratio down to tolerable levels.
Next I would replace that HEI distributor. Accel sells blueprint replacement HEI units. That would probably be good enough. I might look for something better, but the Accel HEI would probably be the best bang for the buck.
Now we move up to the top. I would get Edelbrock's new Performer RPM series manifold with the new Air Gap feature. This is a new design. It is a dual plane high rise manifold. Taking advantage of the dual plane for low RPM torque while gaining high RPM horsepower through the high rise feature. I have heard this is a much better solution than the old Torquer II manifold. The Air Gap feature puts space between where the air/fuel flows though the manifold and the underside of the manifold where there is a lot of hot, splashing oil. This helps keep the incoming air/fuel mixture cooler and denser for more power.
I have heard a lot of good things about Demon carburetors. I would like to try them out, so I would get a 650 CFM version of their Street Demon carb. That should be enough to feed this engine.
That should be enough to get close to 400 horsepower. At the least it should be able to put out 1 hp/ci and have at least 350 horsepower.
If I get ambitious I may get a 383 stoker kit. These kits use the crankshaft from a 400 c.i. small block to increase the stoke of the 350. It yields 383 c.i. with the .030 over pistons. To perform the 383 conversion would require, at the minimum, a properly prepared 400 crank, and special pistons that would allow me to use the connecting rods from my 350. The pistons would not be cheap, but this is not an uncommon combination so at least they would not be as expensive as custom pistons.
With 383 cubes I should be able to get over the 400 horsepower mark. I might need a bigger card to feed that many cubes with and make that much power. Oh, the pain.
Let's add things up. Cylinder heads about $800-1000, bearings and gaskets $200, manifold $200, distributor $200, carb $400. That's $1,800-2,000. Figure another $500 for the crank and pistons for the 383 upgrade and to have the assembly balanced. Not too bad.
I am a little out of touch with all the pricing it would take to build an engine from scratch, but I would expect to spend at least $3,000-4,000 to build a near 400 horsepower engine starting from scratch. Edelbrock sells crate engines in the $4800-7000 range for 310-410 horsepower. The only crate small block Chevy I could find on Summit Racing's web site was $2995 for a 350 horsepower 350 engine. Jeg's sells Chevy's own crate engines. They start at $3200 for a complete engine with 330 horsepower. Jeg's also has Edelbrock's engines starting at $4200, saving a good chuck of change from going to Edelbrock direct.
With those prices using what I have looks like an economical solution.
Wow! All I need is a decent car to stick this engine in. If the car was nice enough I might spring for an electronic fuel injection system over a carburetor. Now what car should I put this in. Let's see... Oops, I said that would be for another article.