Took these pics at the Rapid City SD tour, nice new replica Overhead by Dave Szumowski.
Real nice work, he has lots of miles on this design.
Also, Dave was running his great big Dual-Overhead Cam Model T engine....click on the You-Tube video I uploaded, turn on your speakers and hear this beast roar
You Tube video of Dual Overhead cam Model T engine
What do you have to do to the drive train? That eng. looks like it could blow the spokes off the wheels just idiling.
I'm fascinated and the similar things happend back then. I have a repro of a 1925 RAJO flyer where they offer a similar 16 valve OHC head.
But how much Model T is there in above engine? The block and thats it? ;-)
Doesn't even look like the block's a T.
How about some more info. Are both the OHV and OHC heads reproductions? Which OHV head is it? I may be confused on my history, but I thought Rajo never made an OHC head. They had one on the drawing board, but Gallivan took over the project. Is the OHC gear sitting on an original head? If so, which one?
Maybe it's just me but I fail to see the point in building a top end that will "breathe" great at high rpm and put it on top of a block and crank that wasn't designed to spin more than 2,500 rpm before it self destructs?
Don't get me wrong, I understand that there is a "historic race car" component to all of this but for these heads to do what they are designed to do, you'll also need a 5 main bearing block and crank and a fully pressurized oiling system.
I'm cheap and lazy. I'm afraid I'd just go out and buy a Pinto 2300 or an old "Offy" Indy car engine and be done with it.
Dennis, racing back then was expensive, just like it is today where Speed costs money. Look at the prices back then, as found in speedster cookbooks like Secrets of Speed and Fast Ford Handbook and convert the prices to present dollar value and you will see what I mean. A DOHC engine would have needed a 5 main crank and they made those back then with special girdle mounts that were installed into the block. If you had the big bucks, there were 5 main blocks as well.
Of course, engines like this were rarely driven for every day driving. But for the Indy or Brooklands kind of crowd, what a rush, huh?
If I had the bucks and was building a racer, I would see if I could buy one from Dave because it would take a decade or two to round up all the correct parts for a Fronty type head like this. When you are into this type of Big Dog project, money is not the issue, it is about pushing the limits of era correct design and engineering and vintage parts to squeeze maximum horses out, upgraded by modern engineering knowledge.
The issue becomes at what point do you stop before you cheat and start to use modern parts, thereby missing out on the charisma of that golden age of autos?
Modern engineering knowledge? Certainly better fuels have changed things, and electronics for sure, but they knew all the tricks back then.
The only thing I see in old stuff is equal size valves, while modern engines use larger intake valves.