The 5 main engine.

Adam-had'em

Adam-had'em

Junior Member
Terry bertz engine, I cannot find one video of one idling or running built to look stock, the engine is way up there in the intrigued department of my brain, but I will not order it if it does not sound just like a model-a when built, can anyone confirm this? I have seen the video with Terry propping his legs up on the engine stand but it’s running high RPMs whole video,
thanks.
 
Sounds the same. I have one in my car. The idle and sound of a Model A engine is dependent on the exhaust system and the flywheel, whether the 65 original or a lightened one. Also the intake system, whether the stock one with the updraft carburetor or a downdraft Weber or other more modern carburetor(s).

The Burtz engine has less vibration. Each rod location is fully counter balanced. That makes 8 counterbalance weights in total. The crankshaft is heaver, 95 pounds, which makes up some of the mass lost in the lightened flywheel.

With regards to the lightened flywheel, there are torsional vibrations in all crankshafts for a Model A at all rpms. There is a location where the torsional vibrations are zero, called a node. For the 65 pound original flywheel the node point is just forward of the flywheel, which means you do not feel the torsional vibration. For the lightened flywheel the node moves so that now you do feel the torsional vibration. In my car, that has a lightened flywheel, I can feel this torsional vibration in the steering wheel. I have the rubber Float-A-Motor rear engine mounts so I don't know if the stock mounts would cancel that out.
 
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The Burtz engine, Go to the MAFCA convention in Kerrville TX. you will see at least one there. With over 18,000 miles logged on it.
 
Interesting on the Weber carb sound at idle on a Model A.

My "A" has a Weber, was on it when I bought it, and exhaust note does sound different at idle.

It's just air and fuel going in.....why would it sound different?
 
I firmly believe it is the shape of the exhaust that makes the unique sound of a Model A and nothing else. Everything in the engine is just nuts and bolts differently arranged to do the same job.
I cannot tell he difference between the sound of my Burtz engine and the original one it replaces except at higher revs. The Burtz engine runs smoother there without the bangs and thumps of the original.
 
If I understand the OP, he is referring to the sound of the Model "A" when idling slowly and the un-even sound. It is my understanding that this is caused by the flex of the crank, early beaver tail style. I do not have direct experience with this but have heard from others that when the aftermarket counter weighted cranks started getting installed the un-even idle phenomenon went away. As a result, those cranks were taken out and replaced with original cranks.

I don't subscribe to the purist persuasion, but I can see their point. I like the OFFY sound when I get going.

John
 
Synchro909 said:
I firmly believe it is the shape of the exhaust that makes the unique sound of a Model A and nothing else.
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johnneilson said:
If I understand the OP, he is referring to the sound of the Model "A" when idling slowly and the un-even sound. It is my understanding that this is caused by the flex of the crank, early beaver tail style. I do not have direct experience with this but have heard from others that when the aftermarket counter weighted cranks started getting installed the un-even idle phenomenon went away.
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It is my opinion that most people do NOT know what an original Model-A engine sounded like. The reason I say this is most people have never heard a fine-point engine running. The three major things it takes to sound like an original Model-A engine is the shape AND internal baffling of the muffler, the weight of the flywheel, ...AND the compression ratio. Change any one of those three items and the sound is altered from original.
 
BRENT in 10-uh-C said:
It is my opinion that most people do NOT know what an original Model-A engine sounded like. The reason I say this is most people have never heard a fine-point engine running. The three major things it takes to sound like an original Model-A engine is the shape AND internal baffling of the muffler, the weight of the flywheel, ...AND the compression ratio. Change any one of those three items and the sound is altered from original.
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Perhaps so but as I said, I noticed no difference with the 5 bearing crankshaft. There would be even fewer people who are not interested in Model As who would have a clue.
 
I forgot about the compression ratio. That would make a difference in the exhaust note. I had an original Model A in the 60's. Straight from the factory. I loved the way it sounded. My engine with the Weber, high compression, and lightened flywheel does not sound the same, but I like that sound too. The Ares muffler is made from the original Ford drawings so it helps. I took the headers and straight exhaust off because it sounded too tinny and too loud. The performance has not suffered.

My ears have mostly shut down so I don't hear things the same as I did when 18. My car is super quiet when I turn off my hearing aids. It helps on long drives.
 
200 cu in L head.. run at roughly half its potential power output @40 hp or so.. And this is after a Ford Aviation engineer warmed it up. Ford engineering had it at 22hp prior to that..it wouldn’t pull you’re hat off..As it was the automotive market proved the car underpowered quickly, as evidenced by the crisis in developing the V8..no other manufacturer had the money to stick it out with the V8 like Ford did.

Burtz did not redesign the engines efficiency, he mainly addressed shortcoming in the crankshaft support and reflected advancements in design.. he purposely didn’t improve performance.
 
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Right on,
My initial concern is a slow idle taking a trip when everything’s oil flooded and counterbalanced every engine makes its unique sound because a combination of intake fuel mixture internal components and exhaust components…. essentially the engine sounds like it does because it is the engine…. ? ��. I’ve listened to a model a run that’s not had any work on it at all, and several “originals” (restored) are very close but we are talking almost indistinguishable parts of harmonics, The main thing is that it sounds like a model A engine… that it idles down to a good low consistent number and that I get that good “tick, tick, tick, top.” “tick, tick, tick, top,” warping of the crank is not something I had heard before in explanation. that’s just a lot of guts to change to ad 5 mains. a guy just needs to know. I want to build a long distance slightly higher speed rig for weddings and family trips. (And still wand to see model a hardware when I peal back the door to the old power barn.)
 
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