Ooooh NO!!!! Sorry to see that you're having issues with the motor - It looked and sounded so good. Hope the sleeve is okay.
Ugh that’s strange How much clearance at assembly? Can’t tell from pics is the skirt actually touching the bore on the thrust surface? 90 degrees from cl? J
Bummer. What were the symptoms? I'm up to around 320 miles. Egge pistons and Hastings rings on the stock bores as supplied. No undue noises that I can tell. Going to drop the sump at 500 miles so that RKE can inspect the pump, and fit a baffle. The pump is doing fine but I can out-corner the oil on right handers...
I was on a drive Easter Sunday and was cruising @ 1600 rpm in 5th. (@60 mph), started up a grade and down shifted to 4th. Was running @ 2500 rpm and it started to "labor". Oil pressure was @ 35 psi. and engine temp was @ 155deg F. the power dropped off like it was binding up. Pushed in the clutch and pulled to the side of the road. Engine was idling fine. I sat for a few mins, oil pressure and temp were fine. Blipped the throttle a couple of times, put it in gear, and drove off. Drove it home and noticed a knock when I parked it. let it cool down, then checked the valve clearance. The valve lash was good. started it up and it was making a very loud knocking noise. Much worst then when I parked it. Thinking it was a rod knock, I pulled the engine. All the bearings are in good shape. All of the fasteners were still torqued to spec. This piston got hot and seized up a little. The scoring on the cylinder is material transfer from the piston. I have checked the bores, and all are the right size ( I had it bored .060" over). All the pistons measure good too, except the lower skirt on # 1 is @ .012" smaller then it should be. I think the knock is piston slap on #1 now that the skirt us not able to guide the piston.
The clearance was in spec at assembly. The piston got hot and transferred aluminum to the walls of the cylinder. I'm not sure of what caused the piston to get that hot, but it did. everything seems to be getting plenty of oil. .
Dan, It looks like the piston heated up and expanded along the internal area supporting the pin. And your measurement does in fact show the skirt smaller in OD than the areas touching, by a bunch. The area where your 3.910 dim is written should be the largest dia on the piston. Maybe the piston cam grind was off index? rotated 90 degs? Glad to hear the pump is working, 35 psi is nice, what oil? Nothing catastrophic, just a bum piston. Best, J
This is what I was able to scrounge up. The hose bit with the clamps looks right. I am guessing the knurled bit went on to a magneto? Since I am running an impulse, will have to do a bit of work around.
Just heard that my cam should be getting ground next week! The cam grinder is insisting that I change the lifters… easier said than done in this motor. A typical T has a large inspection plate and would allow the lifters to be easily changed without even draining the oil. This thing is fully sumped with just a small inspection cover. We’ll see if I can get my hand in there… The top of the engine is looking good tho
That’s the stuff! You could pull off the impulse and get a new bit of hose, and be running by sundown! The impulse is mostly a hand cranking thing, they have a centrifugal weight that locks em up at some point. And they make a goofy rattling sound at idle too
This fella wound up with all Harvey Crane Jr.’s master profiles. We picked a a profile with sumpin like .228 lift, 220 duration, and are going to try to get 113 centerline out of the stock T core.
Rotoshim fuel pump and filter under test - all good so far! They machined an adapter to fit it in place of the T tap.
Super cool! This is the cam grind that Dema came up with for my T. There is enough to work with, that I can do the Ed Iskendarian trick of reducing the lift / duration to build more torque. Going into a "speedster" w/od pulling power will be nice. Of course I have to get the damned thing in there.
The flat head cam I took out has very similar numbers to yours. 208 @ .050”, .300” lift, and 115 centerline. It built a ton of compression and had amazing bottom end torque. My Sherman head CC’d at 7.25:1, but would build 190 psi dynamic compression. Was too much and detonated sumpin fierce. I had to retard the cam and tighten up the lash to get it to run without beating itself to death. I’m saving it for a motor with a 5:1 head on it…
Looking at this, it looks quite a bit different from your first picture. Can they not machine the body fitting to go directly onto the original Ford fitting? When turning the unit onto the firewall, is there swing space and are there any other clearance issues? What size is the outlet? Is there really a pressure regulator or is an external regulator required? If no regulator, what pressure does it put out? You only need 1-1.5 lb for the 97. I want this unit, if you are part of the test group, perhaps you can pass along the concerns. Thanks. Warren
Then you understand what I asked for. Have a Simmons / Giant Power head, with about 5:1 wanted lots of fill as there is little quench to play with.
What are you expecting from this cam? This conversation is fascinating, I know very little about cam's, but am keen to learn.
Well... not like I know much either. But I can share the general idea. Imagine you have a 5 gallon bucket and a coffee can, how do you want to fit the 5 gallon buckets volume into the coffee can. You can pour it in slowly, or you can dump it in all at once. Camshaft lobe being the determining factor on how the volume from the 5 gallon bucket is allowed to enter coffee can. As this conversation exists during 360° of rotation, the camshaft determines at which point the volume from the bucket, commences entering into the coffee can, and when it is shut off. The coffee can in this conversation might be one cup or 1 quart. Kevin's is the one cup, and mine is the 1 quart. The lobe design determines how to fill the coffee can. And this is where I run into lack of knowledge, but the general idea is... that by changing the lobe design the fill of the coffee can can be adjusted. The camshaft that I requested is designed around the idea of a large coffee can, and a slow fill (5:1 compression and 3,000 rpm max/typical), 1.5" intake & short runner, additionally, the combustion chamber design has very little quench (early flat head pent roof) so less turbulence opportunity. I need a large volume of air/fuel, and to accommodate the low compression, large combustion space and flame front and low engine stress. so imagine taking the above, and then reducing coffee can to one cup. The fill would be an absolute mess. For Kevin's combustion chamber, which is very similar to the V8 60, compact, poor laminar flow over/around the valves, due to shrouding (clearance between valve head and combustion chamber walls), lots of quench due to the low piston to head clearance to induce turbulence, and and high heat loss from the aluminum. The camshaft would be entirely different. this is why are you here about camshafts that have aggressive profiling to fill a small combustion chamber quickly (think sbc) this in turn builds lots of compression, but only for a very short period time. again, this is all "learning / misunderstanding" and I hope someone here with correct me.
It's designed to fit directly through the bulkhead like the original Model A with a 3/4" nut on the inside so you don't need to swing it. They made the adaptor for me to test it in my T as Kevin said. Normally the aluminium body would be up against the bulkhead and the stock Model A (pre-31) pipe and tap would hook up as standard. The regulator is inside the body. You have to drop the glass bowl off to access it. This one is set to 1.9psi. We're not far from where the Strombergs are made so they've advised what was required in relation to flow and pressure. The outlet size is the same as a Model A. Hope that helps Warren!
Thanks @fur biscuit it's all helpful. I'm planning on getting a cam ground for my A, I am thinking about what sort of profile to go for & I'm looking to learn as much as I can on the journey. We also are playing with old (non Ford) bangers at work with non factory grinds so it will help me when we don't get the specs called for.
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