cage2592
Administrator
This was sent to me via a message from one of our members, 'CorvettePassion (Jeff).
Mike wanted me to share the story of this engine. I will try to make it short, but it’s a long story.
I restored my 77 Corvette between 2011 - 2015, and built up a SBC on a ZZ4 short block, AFR heads, Eddy intake, torquey cam. Drove the car that way a couple years.....but it just did NOT have the power I wanted. SO....I decided to replace it with a 406 SBC. Considered a 427 SBC... but decided it was just too extreme for a SBC. SO... I found a guy on the C4 Corvette forum, who has a reputation for being a good builder. He built the engine for me, using a local machine shop in Utah to do the machine work. I made most of the decisions on the parts, starting with a Dart SHP block, AFR 195 Comp heads, Callies Compstar crank and rods, Comp Cams 1.6 ratio roller rockers, Mike Jones cam and a long list of the best parts available. Was very expensive. Over $10K. Put it in the Corvette, and drove it 8000 miles over one summer here in PA. The engine was strong, but right off the bat, I had numerous problems. Initially it turned out the builder failed to clearance the oil pan scraper, and on the first start had an outrageously loud noise. Finally figured that out, and started driving the car. Over the 8000 miles, I had continuous oil leaks at back and front of the engine. I was losing coolant all the time. The valve train was very LOUD. I did a lot of work to try and stop the leaks, but ended the season with the decision to pull the motor. When I dropped the oil, there was metal on the drain plug (did 3 oil changes over the summer). Then I found out the valve springs installed were WAY too much seat pressure for the stock hydraulic lifter. There is WAY more to this story....but I will not detail all of it.
I am having Mark Jones (VortecPro) build a big block for my 69 Corvette project,... so I contacted Mark and discussed the problems with this 406. End result... he said, ‘ship it to me and I will make it right, but you have to get in line’. Fast forward almost a year, and here is all that was found:
- Valve springs were in fact way to strong pressure for factory OEM lifters
- Block had numerous poor machining issues, bores were WAY overbore for pistons installed, and the rear oil galley plugs were loose in the block
- Heads were not machined properly (angled), all the intake valves had excessive stem wear, and valve tips showed very poor valve train geometry and wear... . Exhaust valves were bent.
- Pistons had lots of excessive carbon or buildup... (Mark thinks coolant was bypassing head gaskets)
- Cam and lifters were junk with tracking
ALL in 8000 miles.
Much of the ‘wear’ is deemed to be a result of the original interference with the crank and the oil pan scraper which produced enough metal to circulate through the engine. It was not run very long, but long enough. This is absolutely the fault of the builder who did not clear the scraper on the build. BIG MISTAKE.
It also did not help the valve springs were way too much pressure, and Mike Jones, the cam maker, believed the lifters were being pumped down, causing lots of hammering, clearance, etc in the valve train. All resulting in all the valve train noise and damage
For the whole story, here is the link:
Mark Jones at VortecPro has saved the day fixing all the errors! I cannot thank him enough for what he has done. Obviously, it cost me a lot, and more than any SBC should ever cost, between the initial build and what Mark did, but I had little choice. Had I known about all of it to start, I would have had Mark build me a big block. Would have saved money.
I hope to have the engine back in a few weeks, back in the car for spring.
Mike wanted me to share the story of this engine. I will try to make it short, but it’s a long story.
I restored my 77 Corvette between 2011 - 2015, and built up a SBC on a ZZ4 short block, AFR heads, Eddy intake, torquey cam. Drove the car that way a couple years.....but it just did NOT have the power I wanted. SO....I decided to replace it with a 406 SBC. Considered a 427 SBC... but decided it was just too extreme for a SBC. SO... I found a guy on the C4 Corvette forum, who has a reputation for being a good builder. He built the engine for me, using a local machine shop in Utah to do the machine work. I made most of the decisions on the parts, starting with a Dart SHP block, AFR 195 Comp heads, Callies Compstar crank and rods, Comp Cams 1.6 ratio roller rockers, Mike Jones cam and a long list of the best parts available. Was very expensive. Over $10K. Put it in the Corvette, and drove it 8000 miles over one summer here in PA. The engine was strong, but right off the bat, I had numerous problems. Initially it turned out the builder failed to clearance the oil pan scraper, and on the first start had an outrageously loud noise. Finally figured that out, and started driving the car. Over the 8000 miles, I had continuous oil leaks at back and front of the engine. I was losing coolant all the time. The valve train was very LOUD. I did a lot of work to try and stop the leaks, but ended the season with the decision to pull the motor. When I dropped the oil, there was metal on the drain plug (did 3 oil changes over the summer). Then I found out the valve springs installed were WAY too much seat pressure for the stock hydraulic lifter. There is WAY more to this story....but I will not detail all of it.
I am having Mark Jones (VortecPro) build a big block for my 69 Corvette project,... so I contacted Mark and discussed the problems with this 406. End result... he said, ‘ship it to me and I will make it right, but you have to get in line’. Fast forward almost a year, and here is all that was found:
- Valve springs were in fact way to strong pressure for factory OEM lifters
- Block had numerous poor machining issues, bores were WAY overbore for pistons installed, and the rear oil galley plugs were loose in the block
- Heads were not machined properly (angled), all the intake valves had excessive stem wear, and valve tips showed very poor valve train geometry and wear... . Exhaust valves were bent.
- Pistons had lots of excessive carbon or buildup... (Mark thinks coolant was bypassing head gaskets)
- Cam and lifters were junk with tracking
ALL in 8000 miles.
Much of the ‘wear’ is deemed to be a result of the original interference with the crank and the oil pan scraper which produced enough metal to circulate through the engine. It was not run very long, but long enough. This is absolutely the fault of the builder who did not clear the scraper on the build. BIG MISTAKE.
It also did not help the valve springs were way too much pressure, and Mike Jones, the cam maker, believed the lifters were being pumped down, causing lots of hammering, clearance, etc in the valve train. All resulting in all the valve train noise and damage
For the whole story, here is the link:
Mark Jones at VortecPro has saved the day fixing all the errors! I cannot thank him enough for what he has done. Obviously, it cost me a lot, and more than any SBC should ever cost, between the initial build and what Mark did, but I had little choice. Had I known about all of it to start, I would have had Mark build me a big block. Would have saved money.
I hope to have the engine back in a few weeks, back in the car for spring.
