Quote:
Originally Posted by Hipopinto
Hey all
As you well know I’m new to this group
I have been researching options for engine rebuilding and stumbled across Burtz Blocks
This seems like a FANTASTIC solution to a dwindling supply of rebuildable cores.
Finding a machine shop that can actually pour Babbitt is few and far between
With a counterbalanced crankshaft 5 main bearings and strong rods this should be a bullet proof combination.
I have always read that compression ratios above 5.5 tend to “flatten” bearings with a “modern” crank and bearings could the compression be bumped up? Maybe to 8.5?
The end result would be much cooler running engines and more usable power
My car as it is runs very well but I’m thinking about my cousins car. He has a 31 roadster that my late uncle was dissembling but he passed suddenly leaving an unfinished project.
His core is in need of a full rebuild and I’m only thinking
Thank you all for listening and I look forward to your replies
Dave
|
Dave, I have been around this hobby for over 60 years, ...and professionally since 1997. A couple of things I have noticed during the last decade or so, is the amount of false, -or misleading information that today's hobbyists tend to pass around about Model-As. (Likely happens in other hobbies too with more prevalence since social media has become popular but I see it very prevalent in this hobby.)
I will address two of your opinions stated above. First, while I do not know yours or your cousin's age, I can say with certainty that there are more qualified craftsmen casting good quality bearings in Model-A engines than what was available to the hobbyist some 30 years ago. The quality (-and availability) of good materials used to cast bearings has never been better now than what we had available in the past 50 years. The quality of tooling necessary to do this craft that is found in these shops today is also better overall than it has been in decades. I don't know your cousin's location, but I feel comfortable that he likely has a shop nearby that can more than capably rebuild his engine.
Your second comment about cast (-babbitt) bearings being flattened in engines using over 5˝:1 compression falls into the category of '
People will only believe what seems believable to them!' and I am unsure where your myth came from. For many years prior to insert bearing shell conversions being done on Model-A engine blocks, Larry Brumfield manufactured a cylinder head that had a 5.9 compression ratio factored at standard bore. He also manufactured a Super Brumfield with ratios exceeding 7:1. Many other head manufacturers during the 1940s - 1970s manufactured heads for bangers that often exceeded 8:1 that made great power and the cast bearings lived with those ratios. Heck, many early trucks and marine diesel engines used babbitt bearings and had compression ratios well past 15:1 compression (-nearly 3X your 5.5 number) and these engines provided many, many hours of reliable service. Therefore, it is my opinion that your myth has no merit and was likely started by someone who was stretching the truth to promote insert bearing conversions.
Now with this said, Terry Burtz's engine is a nice piece that does have a place in today's market. I would agree that his combination should be very bulletproof with the internal components that he offers in his package, however with that said, the same can likely be said with using an original engine block as the foundation and choosing a counterweighted (i.e.: SCAT) crankshaft and a few other aftermarket components too. My point is since you are 'new', please keep an open mind as you do your research to understand we live in a society today where people often place inaccurate or misleading information onto the web for unknowing people to read and thus assume it must be accurate simply because they read it on their computer.
