My flathead engine

sanborn

sanborn

Senior Member
I finally got my engine together and it is NOW running. My son is really the assembler----for who I am truly blessed.

One of my goals was to build the meanest sounding flathead around, and I think we have met the goal.

If you want to view it, go to:
http://youtu.be/oPp-DfDRYX8
 
Engine looks and sounds great! Nice test stand too! I got carried away building mine; (full instrumentation, universal mounts, etc.). It's done except for the fuel tank. I'm looking for just the right one and can't find exactly what I want
 
The only thing wrong with this engine is: The run stand, it will deffinatly ruin the rings and that slow idle isn't doing the lifters any good. The best run stand is an old tire and a jumper cables. Now make sure you run this allot on the stand before you pit a load on it. Sorry, I hate nice run stands, but it does sound great.
 
Sanborn... Beautiful!! Can ya give us some info? Cam, Bore/stroke, CR?

Ol' Ron... How does the run stand ruin the rings? And damn good idea on the spare tire!!
 
I appreciate everyone's comment.

Now for some specs:
1950 Merc block
3.3125" X 4.00"
Comp Cams "Muther Thumper" cam
Aluminum timing gear
stock rods, shotpeened, rebushed, resized
Intake runners enlarged, polished
Lots of work on the "hump" in the intake runner
Exhaust is cleaned up, edges rounded
The guides are profiled to aid flow
Perfect circle valve seals
Isky springs
Flathead Jack valves and retainers
Vertex mag- external coil
Compression ratio- 9.70 to 1-----That sounds high but you need that much compression to make up for the overlap of the cam.
Wilson & Woods heads- 58 ccs after milling---These heads are great, machining is great, consistent ccs. Lot of area over the valve for flow.


I can probably list another 30 mods. If you have further questions,
just "ring"

Ron, I appreciate your comment----but the idle speed is 850 RPM. We checked it twice. The engine is now off the run-in stand (another flathead is on- a stroker)

Someone asked the question about excessive run-in use being bad for an engine. It is because the engine is never loaded and the cylinder walls tend to glaze and not let the rings seat.
 
I've read mention of running the engine on a stand, and being bad for it...but is this because of older tech rings?...I've never had an issue breaking in cams on belly button engines on a stand (20-30 minutes run time)...and putting them in the vehicle.

To the Op...sorry, my connection is to slow to get the vid running...looks danged nice tho!
 
A couple of other questions that I did not answer:

Yes, the heads, intake and gear cover is powder coated. I am getting too old to polish on aluminum or chrome.

I think I will powder coat(black) the air cleaners.

The pistons and heads are ceramic coated. We have used this in the past on our race engines----Why not on this last street engine!

I am sure most noticed we converted the block to 66% filtered flow.

One comment----I am using Flathead Jack's stainless valves. I was super pleased, when used with his retainers, no shims were needed. Also, no back cutting was necessary---they were ready to go out of the box.
 
Have you ran the motor in a vehicle yet. If so how do you like the cam. Ive tried to get feedback on the thumper cams but never could get any for a flathead. Thanks
 
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