Speedster guys realize that a big limitation on HP from a T block is the firing order as related to the siamese intake ports. Intake cam timing is quite limited to any practical advantage. Various solutions commonly tried are opening up the intake ports and adding a divider. The 2up 2 down does work as well and certainly allows big intake ports
Another option considered is to run the engine backwards, but this certainly complicates a number of things. The rear axle is easy, the transmission bands is a bit tougher. I am told some guys have in fact had special camshafts made. I have never heard how they have worked out.
The thought occurred to me to change the cam drive to a chain and just run the cam back wards. I wonder if it has been tried?
Running backwards will make not make any improvement but changing the intakes and exhaust ports will make a huge improvement. The hot exhaust gasses need to get out quickly and making the intake ports into exhaust ports will do wonders. The intake gasses will stay with good performance through the two old exhaust ports nicely AND HAVE TURNED 160 miles an hour IN THE QUARTER MILE I have seen flathead Fords drag race with this system and are very successful.
Essentially I was saying that the desire was to use the existing intakes as exhausts and the existing exhausts as intakes. I have heard of it being done with the flathead V8.
Here's a recent thread where counter rotating either the camshaft or the whole engine was discussed briefly: http://www.mtfca.com/discus/messages/331880/384920.html?1377789277
Thank you. I obviously missed that thread
Well I did some more research and have designed and priced out a double row #35 chain drive. All the parts would run about $135.00. Of course they would need some machining. I figure to do some more designing to see if the generator could be driven as well. It would probably bump all the parts to about $180.00
An alternator does not care which was it is spun. (I hate to think that I may be contributing to your sickness)
The problem may not be direction so much as how to chain drive it and the cam at the same time. I would be interested to what Les comes up with.
Ed and Hal
As I figure it, Felix has shown that the concept works. I realize that some have expressed "miss givings" about the cooling around the now exhaust ports. Having spent way too much time studying the water jacket passages of the T block, I have concluded that should not be a difficult thing to handle at all.
So I am just trying to come up with a less complicated solution. I think Felix probably had to rework all the band actuating mechanism to be the "cams" onto the other side to get good action. I draw this conclusion from the fact that Ford completely reworked them for the RHD cars.
For this application I figure the generator drive is not totally necessary, but if I can solve it easily then I will. Actually my focus there is more on being able to drive a accessory water pump/ magneto drive. As I hope to make considerable HP I think using a water pump on the RH side and injecting the water flow into the "core plug" holes may be a integral part of success. Considering I have several sets of these castings then it all kind of falls together.
There is know cure for my sickness, but hopefully it is not fatal!!
The only reason an alternator might care which way it is spun is if it has a cooling fan, in which case the fan might not work as well when spun backwards.
This is a really interesting thread.
I did some quick web searching of reverse flow Ford V8s. There are/were some guys who could grind new reverse flow cams. Maybe they could apply their V8 knowledge to the T cam.
If the cam is reground to reverse flow, would it also be possible to change the firing order to eliminate the siamesed intakes? I know that you can get a cam that changes the firing order for small block Chevys?
I have some Rajo heads and noticed that the valves are really shrouded due to the combustion chamber shape. I think using a flathead reduces the amount of valve shrouding, so if air flow can be improved by these exotic methods, some serious T power could be achieved.
I love Fast Fords, so please keep us posted.
The "problem" of the siamese ports is related to the 180 degree crankshaft. This is why the 2 up 2 down is a success. In fact I do have a old one of these cranks sitting on the shelf. But to do it justice it needs a really radical camshaft.Of course the reverse flow engine could use the same camshaft. It is nice if a person can find out what others have tried with success. The catch is this kind of stuff is usually pretty jealously kept secret
The real problem seems to be that two pistons are always moving together.
If you could cut the crankshaft between #2 and #3 and turn it 90 degrees and weld it back together, then grind a new camshaft or cut the camshaft in the same manner, turn it 90 degrees and weld it back together, it might help a great deal.
Then the firing order could be 1,3, 2, 4.
Les, you can buy a belt-driven VW bug alternator with shaft out the back for the fan (air pump). Mount it on the left, and bolt your waterpump to that.
Certainly a consideration. The thing is I would much prefer to bring the water in on the RH side (like Fronty did on there high HP engines
Lots of options
Les, I did use a chain setup on an A engine. I called Cloyes, the biggest timing gear and chain manufacturers, and asked the engineer if there were any timing chain sets with the Model A crank to cam center distance of 4.154. He checked and said nothing was manufactured with that close of center to center distance. The T distance is even closer at 3.937. I accidentally discovered that a late 302 Ford double roller gear and chain set could be made to work. In fact the model A and 302 crankshaft snouts are the same diameter, so the crank gear went right on after widening the keyway groove. The cam gear needed some lathe work, and then it went on. I removed a couple of links from the chain and it went on. It was still a little sloppy, so I made a tension-er for the slack side and it all worked. I don't know if there is room for the gears in a T block, but you might check it out. By the way, the Cloyes engineer said that the 144 and 170 Falcon 6 had the closest c to c distance of any chain set.
So I am assuming you accomplished reverse flow on the A engine.
Please can you share more with us about this?
There is an old gentleman who competes in our local F.A.S.T. hill climb event. He drives a full bodied model A coupe and usually with a passenger along for the ride. This guy regularly smokes the hill faster than most of the speedsters. He runs a flathead A with a reverse rotation cam, so 4 intake ports and 2 exhaust. He told me he used 302 small block Ford timing chain and sprockets and drives the car regularly, not just racing.
The T distance between cam and crank of 3.937" is interesting since it's the same as 100 mm. (I suspect hungrarian influence there through Galamb, Balough, and Haltenberger http://www.mtfca.com/discus/messages/118802/125176.html?1266416603 )
Great you could find fitting sprockets, Les - I just looked in one machine parts suppliers catalog. You would think some european or japan engine has the same distance, but it's a bit close for chain and sprockets and hard to research if you aren't into the auto parts business.
Roger, how many other dimensions in the T are stealth metric? The T has lots of the odd 15/16 fasteners, which is 24 mm, now that you mention the relationship. Is 24 mm a common fastener size in EU?
I simply went to my industrial catalogues (Morse in this case). I picked a double row #35 as it seemed to fit nice. Easy enough to select a couple of rough stock bore "hub style" sprockets. I then calculated the chain length and I will have .222 of a pitch slack (which is .222 x .375"=.083"). It will likely be OK, but I can alway add a teflon rub bar on the slack side to take out any vibration. I guess I could even make it oil pressure energized. Maybe too complicated, but worth considering.
To drive a generator or accessory I can just continue the chain over the cam shaft and around another sprocket. Now I would probably add a small idler on the slack side close to the generator drive. The smallest available sprocket is 1 5/8" OD so it wouldn't take up a lot of space. Mount it on a needle roller bearing with a eccentric device.
I stumbled onto the 100 mm thing a number of years ago. I was trying to figure out the correct length for a "link" to set up my line bore rig. I found a set of NOS straight cut gears and tried to figure out from them. Eventually I realized if I went considered them "modular pitch" (metric) everything "fell into place". So I made a 100 mm link and never had a problem getting perfect gear mesh again. I figured it was an attempt to make it tougher for others to copy Ford and slow down the "spurious parts" suppliers. I sure can't prove that though.
If you want to improve the intake gas flow why not open up the intake ports all the way to the studs and then add a divider to create a four port head. This use to be done in post WWII low cost racing in England until it was banned. It works spectacularly well, I saw 95 mph from a 750cc engine in 1950.
The divider can be part of the intake manifold so no metal is ADDED to the block, adding is usually no legal to the regulations, but manifolds are free to modify.
This technique requires virtually no precision machining, the port can be ground out by hand and manifolds are easy to fabricate. No camshafts to create, a commercial 280 should be fine, and no chains or generator modifications are necessary.
What you describe has been done many times before. I did it on the speedster I finished in the '80's. And yes it works quite well. I was pulling about 65-70 HP using a single Holley 94 and a 4 runner intake manifold (the car would do 100 mph quite easily).
So why go reverse flow?
1. The exhaust ports flow better than the intake ports, even opened up. They line up directly with the valve and they can be ported out to the optimum size (which is the effective open area of the valve). Fordson tractor valves work well and thus need a bit more port too. Now you need to be concerned with "valve shrouding" by the head at the edges. Also solvable by using a copper shim head gasket and doing some work on the combustion chamber, but I digress.
So you can get bigger useable intake ports and better flow by going reverse flow.
A commercial 280 cam is NOT going to be enough for this project to make it worth while. I used a 315 lift and long duration model A full race cam before. With the 4 intake ports I had good bottom end and it would pull hard to 4200 rpm (I had T valve springs and the valves would start to float so I had a built in rev limiter). Below 2500 rpm if I stood on it, it would break the clutch loose so I had torque limiting to the rear axle (needed more clutch spring I guess).
I figure about a 350 lift cam and 260 degrees of duration might work out and I have one of those in hand.
The key to HP with any engine is getting the air in!! That is why people use blowers and turbos. You only have atmospheric pressure to push it in. The pistons will push it out (sure you want make it easy too).
So I figure the chain drive is beginning to look easy to do and relatively cheap too!! The new camshaft is just part of the package. Now I suspect that a 280 cam with a reverse flow set up will out perform a 280 in a conventional installation assuming a good big carb set up. It just occurred to me that a friend of mine was talking about using 4 Holley NH's and that could work with too.
Les, the Model A engine that I did went to a new owner and he has never installed it in his car, so I can't give you a report on how it ran. There were a couple of reversed port A-B engines running at Bonneville Speedweek. As I recall they ran very well.
So I assume it was intended for speed. Can you tell me about the camshaft please?
Les, I used a Brierley cam. It was actually a Winfield SU1A, ground on an early 1928 5 bearing cam. It was 285 duration with a .362 lift. This is the cam that Jim Brierley recommended.
Thank you for the information. I just talked to Jim's wife I guess and he has a medical problem so may not be able to help me soon. I hope he has a speedy recovery.
Jim had bypass surgery.
So I had a chance to draw out the chain drive. It actually all fits with probably only a little bit of grinding for clearance in a couple of spots. For what it is worth the generator would turn it's usual direction.
I'm sure there's some way to mathematically calculate the advantages or disadvantages of running a reverse flow versus porting the intake. From what I can gather, the upside of reversing the flow is that the block remains completely or nearly completely original. The cam, manifolds, and timing set won't be original, but the rest of the engine will still be factory. Maybe I'm missing something? A buddy of mine has been kicking around the idea of attempting to build a car that will either turn 100 hp or go 100 mph, whichever we can get to first. I suggested this to him, and in our discussions we're pretty sure this is the easiest way to build an engine you can easily restore to stock if you wanted. Just another thing to consider when weighing your options. I'd love to hear how such an engine performs.