CHP Owed A Big Apology

I am the cause of the catastrophic failures of my two CHP strokers. Right off the bat, I want to publicly apologize to Coast High Performance, who did a great job building my two engines. Failure analysis is difficult and time consuming. Cobra owners are quick to point fingers at the engine builder for lack of better evidence. For the last week I have been working with the cobra lads to find the true reason for my spun bearings. Lack of knowledge on my part, caused the oil starvation.

I want to thank both Grover and Bruce, for spending so much time with me this week, going over each and every detail of the failures. Without their guidance, the mysteries would never be solved. They did not buy into the various theories posted on the cobra boards. Instead they used logic and probability theory to follow the proper clues. Grover is a ground-retired system engineer who spent the last 10 yrs as Chief engineer for the Air force development center. He has done over 100 major failure analysis on submarines, missiles, B-52's etc. Bruce is a engineer for Atomic Energy Canada where he designs and monitors systems in one of the large nuclear reactors. On the job they establish probabilities of failure for systems and components. With military and nuclear, nothing can be left to chance.

The probability of two engines failing is too high. Here are quotes from Bruce and Grover, early in the week.

Bruce writes: "For your case, if you look at different components and their chances of failure you see that most have a low probability. However, when Andy Dunn uses the engine, there have been 100% failures, and its repeatable. Therefore, I would focus on things that are possibly unique about the way you have set up your engine, not generic component failures like out-of-spec bearings. "

Grover writes: "failure no. one is very important; it drives the whole analysis; because; the two engines are independent variables because they were built at different times ,different people, parts, etc. Your gut has you leaning toward clearance assembly cause. Say that CHP builds several engines per week and they would not be in business if assembly failures were common. For this agreement lets say there failure rate is 1 in 100( that very conservative-probably more like 1 in 1000.) For two engines to both have similar failures from the same cause would be a portability of 100 squared or 1 in 10000. Not likely." The search began to determine the parts and systems that were common among the two engines:

Break In Procedure
Oil Pan
Oil Lines
Oil Cooler
Oil Sandwich Plate
Oil Filters
Oil
Carburetor
Heads
Radiator

Many of these items were quickly dispensed with and we narrowed in on a shorter and shorter list. Carb, Heads, Oil Pan, Radiator, and Break In, had little chance of being the cause. Some of you might be wondering about the high volume oil pump and the cam gear. This only occurred in the second engine and the first engine had a different pump. We decided to set information aside as well for the time being.

I used 5 different brands and the engines failed with different brands installed. Even the cheapest of the cheap models filters down to microns. An engine is not going to fail at the 500 mile mark for cheap filters.

This was a Moroso unit and I hand washed it in the sink and tested it before installing on the new engine. It was clean and not restricted. The first engine was broken in with Shell 10w40 and the second with Valvoline Race 20w50. The second engine had the oil changed 4 times. Oil is generally not the cause of failure since most oil can take far more abuse than most people realize.

There was a Red Herring...two days ago I was certain that that I had found the cause of catastrophic engine failure. On my engine, I use a Moroso sandwich plate that is thermostatically controlled. This means that it holds most of the oil in the engine, until it warms up, and then the thermostat opens and lets more oil circulate. This is much the same as a water thermostat. I know of no other cobra using this one. I grabbed. At the bottom of this page you will see the thermostatic sandwich plate that I use, along with the blanking cap.

First I double checked the oil filter mount itself. The holes were large and there were no restrictions. The unit also appeared symmetrical. Keep this in mind as we move on. Next, not wanting to take any chances, I cut open all my aeroquip socketless hose. The nice thing about these hoses and fittings, are they they are completely reusable. I looked down the hoses, I shoved golf club shafts down the hoses, and they all were just clean as a whistle.

I also wanted to check my oil pump at the same time. I used a pump shaft and found I could spin it with my fingers, but it was stiff. This is normal. I then spun it with the drill and made a good mess under the car. Things continued to check out normal. It was onto the blanking cap. It had 4 holes leading to the center hole. These appeared perhaps a little small, but nothing to be too concerned about. The unit looked as it should.

And then I saw it. There was the evil sandwich plate. The unit again looked symmetrical. The port openings were clear and large. I began to remove the thermostat housing to check for metal fragments, binding, or anything that would prevent it from opening. These components checked out fine. Then it hit me like a ton of bricks, look how restrictive that opening is! My heart began to race. This port was small closed and barely opened an additional 1/8" when I pried on it with a screw driver. I couldn't wait to get inside and email Grover and Bruce. This investigation was successful and we could close the book. Grover and Bruce were not buying in. I told you it was a red herring.

Grover writes: Couple of things for you to sleep on: After reading your comments & pro/cons . Your coming to conclusions on gut feel; not driven by facts, measurement and test. Your leaping to the answer without proving the thesis. That a giant no no. You must verify by test the failure theory. Grover wanted me to reinstall the system and test it. I could of done this except the oil pan would be impossible to get back on without removing the flywheel plate. I did every test I could think of.

Bruce writes: I find it difficult to draw an accurate conclusion. However, I think the sandwich theory could make sense. It definitely looks like a bottle neck and this might have put to much back pressure on the pump. I don't know the exact pressures involved or the pump characteristics, but if there was too much back pressure, the pump would be ineffective. It would be ideal if you could hook things up and run the pump as you described. Then try running it with a less restrictive setup for comparison. Was your oil pump designed to work with your sandwich arrangement? Here's what still bugs me: You say the opening is 50% smaller than one of the line ports. That should not be a big deal. The oil should just flow faster at this point ( its complex, but that's basically what should happen ) As I said, I think you need to experiment with it. A lot depends on the pump characteristics, ie. how it responds to back pressure. If its designed for volume flow, with little resistance, then it would be easy for this setup to be stopped in its tracks by a significant flow restriction. You have an extra heavy duty pump, so I would think it would be stronger, but maybe its optimized for flow rate.

Grover then revealed the truth. He could tell from my emails, exactly what had gone wrong. Here is the email that I sent Grover which held the key. Remember all my talk above about 'symmetrical'.

Andy writes...oil filter mount. this seemed to be fine. this is the large unit from Enzo. Huge holes and no restrictions. I may have had the hose on backwards. When I cut open my oil filters, -------the metal particles were in the filter center. Is this right or wrong? I believe a filter would flow almost the same rate in either direction. I do not think I had them wrong, but I just want to leave that open in case it is important. Again, I do not see any issue with the mount block that would indicate any trouble. I think Grover almost jumped out of his skin. There was the answer all along.

Grover writes...You have conformation in your lap!! I didn't ask this question because I thought it was too easy. How does the oil flow through the filter???? It flows out of the engine on the preferential ring (NOT THE CENTER PIPE) It flows over and down through the 10 little holes; pushing down the circular rubber flapper valve. Where does the oil go? outside the element! A proper plumbed filter traps the debris on the outside, oil flow through the element and exit the center threaded pipe. It was plumbed backward- you put oil down the threaded center (into the center; oil flow thru element leaving debris "inside" oil tries to flow out but is stopped by the check. The only oil the engine is getting is what "leaks" pass the check valve. Enough to run easy but not at high power. This also explains why your oil pressure always read high and stayed there. Because where you had the sender you were reading the full pump pressure stopped at the filter. This also correlates with the worn dist gears; pump is fully loaded pumping into a dead end; and getting only a drabble of oil. Tonight I was speculating that this was the cause, I was easing into telling you you switched lines.

I am sad that my lack of oil system knowledge regarding a $5 part cost me two engines. I also greatly regret any harm I might of caused to the reputation to Coast High Performance. I am relieved to finally know the truth. I certainly would of melted engine #3. I am fortunate to meet people online, like Grover and Bruce. I think them kindly for their most excellent help.

Coast High Performance builds kickass engines. I called Tim at CHP today and apologized. He told me that he had heard through the rumor mill that my second engine had spun bearing. He just couldn't believe it. They sell over 300 engines a year to hardcore mustang drag racers, and the engines never come back broke. Pick up a copy of Ford Windsor Small Block Performance (if you don't already have one) and flip through the pages and you will find some of the engines hand crafted by CHP. They literally wrote the book on the 347 stroker. Need another opinion? Give John at Westech Performance a call, and ask him just how many CHP engines they have tested for magazines and see how well they have performed. I have been reading all my engine books over and over, as I prepare to try my hand at building an engine from the block up. My new favorite book is the Official Factory Guide to
Building Ford Short Track Power. This book is a must have for any Ford Small Block builder. Fortunately the 383 took very little damage when the bearing spun. I think the block basically needs cleaning, and the crank needs polishing. The tools have been ordered, and the parts are being stocked. Detailed build stories with photos coming soon!

I wanted to be extra clear on the construction of the non symmetrical flowing modern oil filter, so I ran out to the garage and sliced a new one in half. Here is a Toyota filter which is a little smaller than one for a big V8. Here is the first layer and there are the 7 holes on the exterior which large hole in the center. A rubber one way check valve allows oil to enter the outside of the filter, fill the canister, and then flow through the paper pleats, into the center, and then continue on its journey out the main hole. Next comes the core filter element. These range in size and pleat count. At the top of the can is a metal bridge. It spaces the filter away from the surface so oil can get to the bypass valve if necessary. At the top of the filter is a bypass valve. This filter has a rather nice spring loaded unit. If the paper element become saturated with particulates to the point in which flow is severely restricted, the bypass allows oil to skip filtration and get back to the engine....since we all know that "blocking" the traveling oil, quickly leads to an oil starvation condition and eventually "catastrophic failure".