8 Attachment(s)
Prototype Merc 44 - 4 Carb - Ray Nydahl Based Front End
The following pictures are of a Ray Nydahl based front cased Merc 44 FE Modified in the mockup stage before most of the fitting even began once Tim Kurcz got me going a couple years ago telling me about what he was doing.
The crankcase was designed to fit OMC - 3 Holer modified 6 petal pyramidal reed blocks fitted to the major front cover section (not shown) that originally by design had two Tillotson self pumping snowmobile carbs converted to methanol fuels mounted in line.
The new prototype reed block and carb manifold mount top cover not shown and still in machining stages of simple layout is somewhat pyramidal itself with each carb 45 degrees opposite to the next carb underneath it making a split V formation.
Another very simple flat plate front case cover for the Nydahl front case featuring 45 degree molded rubber carb connection manifolds and on the other side the pyramidal reeds systems is also in the works in an effort to only have to replicate the one major casting going to aftermarket for 4 molded rubber 45 degree carb mounting manifolds involved. Such rubber mounts lend themselves to using carb adapters on top to try a variety of carbs that may be suited to this application.
The Merc based ignition system will be belt driven and will be simply offset by design where the fuel pumps on a conventional Merc would normally sit. By nature the fuel pumps will not be mounted on the engine in a conventional way being mounted on rubber grommets and remote with a short crankcase pulse lines to actuate the 2 of them.
The theme is still to keep this engine as Mercury as possible, light and compact with all support peripherals close together.
Bayer aluminum exhausts are the preferred system to keep exhausts light weight.
To make the engine as total Mercury as possible and have no OMC parts (the reed blocks) I managed to get Mercury Snow Twister engine 8 port, 8 petal reed blocks for custom fitting. Other more up to date modern racing reed systems are also being looked at to keep parts more on the current side with current availability.
The question remains what reed blocks system will work best? The original Mercury reed blocks (brass ones are being used) are still there but blocked off completely.
Once all the prototyping is finished the prototype front case part (hopefully only the one casting part system) will be setup to make mold(s) for lost foam casting processes for making more aluminum copies in the future. The idea is to make the casting to fit any year or version of Mecury 44 cubic inch production engine block except the 44X type newest blocks.
Next summer the fully built prototype block completed will be featured in this section of BRF. The engine block side is all ready assembled using a center of cylinder sparkplug configuration block common to the early Mark 58s, Merc 400s and 500s and has the Bayer exhaust system in place and uses a revised though stock based in situ cast in liners with 4 intake and 4 exhaust wide port configuration to increase breathing and flow capabilities.
Enjoy the basic mockup pictures for now.
Aparently they are just pulse line outlets.
Tomtall: Aparently the holes you are pointing out were just some kind of pulse line hole for a line to the inlet nipples to the fuel pumps built on the carbs. There is a kind of bolted up on each side flange there with a hose nipple. I still have one of those somewhere but never had the two. That was done because the casting is not that thick there so holding a flange with an onboard nipple with a gasket between the casting and the flange was employed with two hold down bolts was for security. From looking around though any manner of pulse outlet or fuel pump type like a Mikuni pump could have still been located without much trouble in several alternate locations on either side of that crankcase. That is today's hindsight, always good but not always looked at back then with what was then avialable and thought to be standard or practical.
As I understand there was a velocity problem that very well could be intake overkill with a total 4 to 6 entry points to reedblocks in one engine feeding 4 crankcase sections / cylinders with two oversized carbs with Tillotson HD size barrels. This crankcase front was designed for use on Quincy Flatheads with the bolt pattern that used Mercury 4 cylinder front crankcase covers as earlier Quincy Flatheads did until they made their own all Quincy units later.
From its condition it did not look like it got much use on a Quincy Flathead engine. It could be an experiment that did not work up to expectation and was abandoned. Here it is again being given a different turn at use all over again.
Taylor-Nydahl 4-carb Merc
Hi John. Looks like a pretty nice casting, most likely built for alky as you stated. Mod has a rule that says no "made for racing" parts, and that a "recognizable service block and crankcase" must be presented for inspection. Had these rules not been in place, a one piece casting would have been built for the 444 similar to the Nydahl piece.
The alternating up/down inlet bevels show it was built for the uncut OMC six-port reed cage shown. Don't dismiss them too quickly. They are quite compact for the tip length and area. This allows good flow while containing crankcase volume. If you go with the rubber adapters, my suggestion is you use the narrowest spread possible, or use straight in self-pumper snowmobile carbs as designed to keep mixture flow straight as possible.
Also, it looks to me as if the three-hole patterns on the side are for an early OMC (single chamber pulse) fuel pump. I'm guessing these were added after the fact to support float-style Merc KA or KC carbs. Possible reason: I tested self pumpers on an OMC 25SS mod in 1975 with no success. My guess at the time was the split pulse reduced performance.
Be sure to keep us informed with your build. It looks like fun! Meanwhile, I'll post some internal 444 shots to help your development. Good luck!
Tim
That part of the rules is the spoiler..........
Tim: I realized when I saw your version that you had the block and crankcase for the motors represented to the public as per the rules and then you made a stacker casting to add the carbs and reeds systems in a similar way in effect adding material to the exterior of an existing crankcase and getting what you wanted within the rules, resulting in a real good engine doing so. Here I am in fact taking away metal??? A whole crankcase front to avoid re-inventing the wheel knowing that the Alky effort back then around 1970 using that crankcase by Ray Nydahl that did not work in the way he intended it. LOL!
Looking at your casting this crankcase could be re-prototyped to be re-developed the way you did yours but then it would be easier to buy your castings and do it your way with some personal touches your probably well on your way to evolving. Any way you look at it you started something here with multi-carb (4 carb) unlimited Merc 44 cubic inch engines and you are to be commended for doing so as it stimilates interest.
I had a feeling you were going to read the riot act (the rules book) to me at some point so soon enough your going to see another version where the Merc 44 engine has the two front carbs as you would find normally but also has 2 more slightly smaller carbs, AJ Tillotsons mounted opposite the fuel pumps on reed boxes 90 degrees over from the front carbs feeding a Quincy pioneered 3 rd port variant system between the cylinders except the 3rd port is not feeding through the center of the crankshaft surrounding reed blocks up their middles. I heard that this is not re-inventing the wheel either and have heard that Quincy 3rd ports did not work either, which I don't buy but here on gasoline and with some different approaches, who knows? The viability just might be there as well? It sure is a lot of fun trying though isn't it!!!! :)
I believe Deflector development stopped way too soon.
Tim:
I am a believer that deflector development was dropped way too soon when everyone abruptly switched from deflector or loop charged. Your 444 project shows something about what could have been back then but that didn't happen. In going through all kind of wrecked deflector Alky engines there was very little innovation going on to getting a faster colder air/fuel transfer through multi-carb pyramidal reed systems back then though the parts and principles were not unknown. The same thing in terms of shedding heat faster from a 30% bigger crown that deflectors had more than loop engines. The exhaust and intake ports could have been widened for fuel cooling and faster heat release but everyone stuck with 3 holes on each side of the cylinders. There was also serious innovation in the UK when it came to crossflow piston crown and combustion chamber design that equalled in terms of power and performance what loop engines could do without the heat soak in a deflector crown with some real differences. In the onrush to switch even that technology was patented but got lost in the onrush to loop engines.
I think that engines like your 444 effort, my effort and other efforts out there are restarting the further development of Deflector engines from the standpoint of their design where greatest power is developed at lower rpms. At the point they were dumped for loop engines they were trying to develop Deflector engines as high rpm output engines which is a place we have come to know they just cannot go. With that in mind and innovation we are going to see more engines like yours, the unlimited 44 cubic inch gasser FE types. Does SE class have any future worries from 444 type engines? Yes, from anyone wanting to get away from severe vibations that threaten to knock your false teeth out of your mouth landing them on the raceboats floorboards for later retreval and reinstallation! 444s do not suffer from those kinds of vibrations unless you blow an ear off a prop while underway. :)
Dyno horsepower was big early.......props & boats played catch up.
Tim:
The horsepower dyno figures with the advent of loop engines coming on stream in the 1960s sure must have seemed extreme in comparison to the deflectors of the day whose power curves steeply curved off while the loop engines power curves just kept going up.
This wholesale change from deflector to loop as my racing neighbour put it, put out horsepower to such a new extreme that props and raceboats are going to have to spend some time to just catch up. It was just after that time 1967 where we had Hubbel reed valves installed on my first KG-9 with Ted saying, trust them, they will make your engine faster. He was right. Local rules allowed that modification to KG9s, 40Hs and Mk50s to get them just a little more competitive with Merc 55Hs which even then were long gone allowing them to play by themselves in their front running pack while us poor followers hoped they forgot all about us growling in the rear hoping all their playing would blind them to us being sneaky to pull in amongst them with the hope of not being noticed to place higher.
Seems with the your 444 concept we can start doing some of that stuff to find some combinations that work all over again. One of my locals suggested getting 4 small self pumping chainsaw carbs and mounting them on a Hubbel reed valve concept blocks somewhere on the transfer tunnel on a Merc 44. Tim, with (in addition to the standard front mounted carbs) your concept engine built is breeding all kinds of ideas with characters since the engine was posted here on BRF. Hopefully all those ideas become some more engines. :)