T-5 5 speed trans VS Mitchell overdrive

The controlled orifice to the timing gear is necessary in a fully pressurized engine,you dont get the waterfall effect of a gravity fed system,you have to provide a controlled volume of oil to keep the gear lubricated.
Without cross drilling the b crank and pressurizing the rod bearings,basically using the ford system,you dont have to provide constant pressure oil to the timing gear.Dipper rods starve around 4k,they cant pick up the oil at that speed.Modified flathead doesnt turn that high,torque peaks at 2700 or so.Dave proved his lower end beyond a doubt..
 
"Dipper rods starve around 4k,they cant pick up the oil at that speed."

They could pick up the oil if there was oil to pickup. Depending on the design of the system, the dipper will cut a groove in the oil when it picks up oil on each rotation. As the rpm increases, the time for the oil to flow back in the cut groove under gravity, becomes less.
When the rpm gets to the point where the oil can no longer refill the groove, the rod will fail due to lack of oil.
 
It takes some work to get a modified flathead capable of spinning 4k..and I give the racers their due,chasing that demon is far further than i want to go,I don't want to be king of the salt,just want to compete with the Kias at a few stoplights,prove a 90 year old design is still relevant..
 
Railcarmover said:
It takes some work to get a modified flathead capable of spinning 4k..and I give the racers their due,chasing that demon is far further than i want to go,I don't want to be king of the salt,just want to compete with the Kias at a few stoplights,prove a 90 year old design is still relevant..
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The problem is, after you stomp a few Kia's, you get greedy and want to stomp anything that shows up.
It doesn't take much more work to go from 4K to 6K but it does take a fat wallet.
 
Love the true racers,their kids eat the putty out the windows while daddy is trying to gain an inch..its never fast enough,you just run out of money and time. I admire and respect those guys,without their innovation we'd still be running 40 horses and two doors..
 
denniskliesen said:
Why do you need a solid stop for the cam plunger? What material did you use to make it? Why do you need to spray the cam gear with all the oil spraying around in there?
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Soild cam plunger stop: The high capacity oil pump, a tight oil pump drive gear, fuel pump, varying lifter loads or a tight distributor can all cause the cam to move forward. The solid stop is a 1/4" NF bolt installed in the center of the cam plunger boss in the front timing cover fixed with an external lock nut. This bolt passes through the center of a stock plunger spring. The plunger spring still applies pressure but the stop bolt limits the movement to whatever I set the clearance to, about .003". There are other methods of doing the same thing. My solution is an easy and low-tech one.

Oil to the cam gear: In my last performance build, I had an adjustable timing gear failure. The failure was likely from a front journal ground .0015" off center resulting in varying timing gear clearances. The oil passage from the galley was reduced to a #50 drill size and it directed the oil to the side of the gear rather than directly to the teeth... so maybe lack of oil was a problem. I think both issues contributed to the timing gear failure. I had the crankshaft grinder correct the off center gear issue and whether the direct oil spray is necessary or not, I have the oil pump capacity so I dedicated some directly to the gear. This engine is a touring engine, not a racer. Finishing the road trip without a trip stopping break down is the goal. To me, the worst finish to a road trip is an accident, the next is a ride home on a flatbed. Failure is not an option!
Good Day!
 
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I run the same thrust button setup in mine,spring pressure with a few thousandths stop.I couldn't find a mechanical reason why the cam would thrust,the timing gear back lashed perfectly,the cam bores and bearings true,distributor drive gear and oil pump checked..new bronze gear and crank gear. My conclusion was the same,added load forced the cam to overcome the spring pressure.You have to kill the thrust,valve timing will alter during the thrust due to the helical cut gears.
Full pressure on a touring engine is most you can do,no doubt.Model A gravity feed/dipper system works well for a modified engine driven on the street,it doesnt give the comfort of an oil pressure gauge showing 25psi..thats priceless.
 
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