Have you ever noticed that a Thickstun PM-7 is offset?

After reading this I checked my Tattersfield. It's also offset to the driver's side. Never noticed that before. It's too cold to take a shoe off so I guess I won't worry about it.

 

Offset your air filter by the same amount so you don't notice.

 

Here are the pics you guys wanted. It's a work in progress, so pay no attention to the wheels and tires. They are just my rollers... the wheels, drums and backing plates are still at the paint shop. The ass-end needs to come down some as well...

 

Really? You have any pictures of it, I'd like to see.

You know what? I was thinking about doing that last night. Warped minds think alike ...

 

What's the dizzy???

That's a damn good lookin' flatty.....

 

It's a dual Wico V-drive. I cast two 90 degree mag adapters for extra radiator clearance, that may be why you don't recognize it. I converted the mags to electronic distributors too, the cranking speed wasn't fast enough to light the mags...

 

That dizzy is a rare dual 4 cyl magneto adapter. Allows you to mount 2 4 cylinder maganetos in a "V" formation on the front of the engine. They also made one that mounted horizontally. ==O==

It basically means that loudpedal is one of the cool kids.

 

Is this car a replacement for the other black roadster (used to be yellow), or is this that roadster getting rebuilt?

 

It's my replacment. Hopefully I can hang on to it a while

 

They look great on the motor, Nice job !


CBB

 

Nice heads..........oh yea, and heck of a great looking roadster..........are your heads cast iron? Or Aluminum?

Chris Nelson
Kansas

See you on the Salt........

 

The heads are aluminum. I have a set of head covers that I'm painting (the same way I painted the air cleaner). I painted the heads black because I didn't want to have a polished stripe between the head cover and the block.

 

You guys do know that the ports side to side are difference(at least on a late flatheads that I did cutaways on) on a flat motor.Going out to dinner will see what side is longer latter. Might be a speed secret ? Anyone talking?

 

...No I didn't. I'm grabbing my calipers...

 

I just bought a thickston here on the Hamb and got it yesterday...noticed the same thing. Wierd!

 

Those must be some nice head covers if they are good enough to cover those Thickstun heads.

I like those heads.

JH

 

Damn it! I may be interested in selling/trading a fully polished original PM-7 w/ matching air cleaner for an Edelbrock/Weiand hi-rise. That offset would drive me insane. I never knew it was there and mow I do. God Damn It!

Any takers? Shoot me a PM. My set-up is really, really nice. Would only trade for same.

 

Actually, Sharps intakes are offset, too, as are Eddy four barrel ones. Must have something to do with the different port angles, side to side, on Henry's water heater.

 

OK, cooler heads prevail from my previous post.

I went out and checked it out. Now, I forget which side it favors but could it have something to do with the crank not being in centerline with block? The crank is actually offset to one side of the block (not sure how much or to which side).

Being Thickston worked closely with Edlebrock. Sr. & Tattersfield, could it be the thought was with the carbs that high off the deck surface of the block he tried to "cheat" the flow of the intake charge to one side in order to compensate for the offset crank?

Just a thought

 

Driver side intake of block is longer.If I told you more I would have to kill you.Some of those old fuckers were on the ball.Some are probally laughing in their graves. Henry's lump was bad ass.

 

I don't mean to sound like an authority so please don't take it that way. The pre '45 blocks had the valves on the right bank @ 45 degrees and the left bank valves @ 52 degrees. The crank is offset 0.265" to the left when facing the front of the motor from the camshaft; however the engine is prolly set with the crankshaft in the middle of the frame. This may cause the intake to be offset to the right by 0.265". Since the valve angles are different and the crank is offset the runner length from the joint at intake deck and the head deck corner to the valve centers is longer on the left bank and the internal runner length from the deck to the valve stem centerline as longer as well. The Thickson may have compensated for these runner length differences but I can't say that for a fact. See the attached CAD drawing with the dimensions circled in red as well as the dimensions shown just beneath the circled dimensions.

The dimensions for the 59 series engines would not be the same as the valve angles were changed prior to near '45.

 

That explains it all. Thanks blown49...

This raises other questions in my mind. The most obvious being why Ford used different valve angles left to right? Because of an offset crankshaft? ...Then why an offset crankshaft?

 

The offset crank I think was discovered by an Englishman or a Frenchman I think but can't remember his name. (Begins as Duxa or something like that) The engine is supposed to run smoother with that set-up. and you gotta admit Henry's stock flatheads are smooth at a low idle.

Also note from the drawing I posted that right and left cylinder centerlines are offset by 0.1875" clockwise on both banks crankshaft centerlines and that also seems odd.

So I guess we ought to state the cam and valves are offset left of the crank 0.265" instead of the other way around.

Also the 59 series blocks had the valves on both banks @ 50 degrees. Supposedly the left bank was changed from the 52 degrees to 50 degrees to move the valve heads further away from the cylinders because of heat. Some old time flathead "experts" I have talked to stated that the left bank valves always burned up first on the early motors. This could be fiction hell I don't know!

 

Tim/Bruce got to thinking about this today. Since the pistons are centered ahead of the rod/crank centerline during rotation the rod to piston would be knuckeled @ TDC allowing the pull angle of the piston to not be straight. I drew it up in CAD and it's exactly 1.5 degrees.

Now what's this about the timing bump being about 2 degrees before top dead center? Hmmmmmmmmmmm.

 

The pictures of the ports in this drawing does not really tell the shape story.Maybe I will post some real cut aways during tech week if there is some intress.

 

Flatdog:

Wadda ya mean "If there is interest?" I think at least 25% of this board would interested in that.

C'Mon man, let some of the cats out oof your bag, brother!

 

Ditto...

as far as the intake/cleaner centering issue goes, again, either machine up a new lower section to suit (air cleaner/cover), or visually cheat by either modifying the 2 radiator support bars, or loose them entirely, supporting the upper section of the radiator differently.

I'd still LOVE a PM7....so anyone that upset can sell me theirs cheap...

Cheers,

Drewfus

 

Here is the answer from Frank Baron's son, Tony, who is a friend of mine........read on:

"Hi Brucie,

Carbs are offset for port alignment, proper balance tube size,and heat riser alignment,which made it the best running 2-carb manifold made for the flathead. The thickstun-tattersfield-baron created the first High-ise design that worked."

Tony

Brucie

 

Right from the son of the horses mouth,can"t get much better that that.Those boys did a lot of thinking back in the old days.

 

Brucie:

Thanks for the post. Good to know.