A Hupmobile ???

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Bob, Hope your feeling a little better. I'm with you on some old school pin striping on the dash as it is, would look great. As different as this roadster is it needs a different motor than an every day sbc, a jeep inline 6 would fit the bill. You will figure it out. Good news on the gauges.
 
I pulled the head off the most recent acquisition. It is the best of the 4.0 Jeep heads. Generous valve and port sizes as shown. The guides are tight and the valve seats look good. The exhaust valves are pitted where they seat so will replace them.

I took the other 4.0 apart. The good block which will be the foundation of the dragster engine build. It is all standard and the bearings and journals are mint. I'll save the rotating assembly ( a 4.2 crankshaft will be going in this block) and use it in the block from which I just pulled the head. I'm assuming the rotating assembly can't be as pristine and the one pictured. That will be assembled as a 4.0 and used in the roadster project.
 

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Well Bob, one thing that goes with the nice large size valves is that the head shows little if any valve shrouding. Really clean looking OEM combustion chamber. Very strong looking bottom end with 7 main bearing setup. Both motors will be great in the roadster & dragster. [cl[cl[cl Season Greeting From The Left Coast.
 
I disassembled the second 4.0 engine. The one that has the desirable head on it. It has the loosest timing chain I have ever seen. Other than that, the bearings were well worn and the crank has a bit of scoring Overall, not bad. If the bores aren't too worn I'll drop the rotating assembly from the first 4.0, the one that gave up it's block for the race engine, into this block. It will be a nice warmed over engine for the Hupmobile roadster.

The garage is getting pretty cluttered. Clean up day tomorrow.

Yes, Tom, looks like a good foundation for a stout engine. Seasons greeting to you and Dixie.
 

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Bob, I'm not up on Jeep motors. What Cu In are the two motors & what is the OEM rated HP? How do they compare to the Ford 300 4.9L for size and HP.
Thanks for the kind season greeting.
 
Got all the Jeep engine stuff tagged, boxed and stored until the time comes...

After cleaning the garage I cut the firewall cover out of .063" aluminum using an angle grinder.

Regarding the Jeep engine questions, the best stock 4.0 is 190 HP. The 4.0 is 242 cu. in. and is a big bore/short stroke combination. The 4.2 is 258 cu. in. and has a smaller bore and roughly a 1/2" longer stroke. Fortunately the 258 crank fits in the 242 block with no modification. just need to use stroker pistons. With a .030" overbore it is 280 cu. in.

The mild engine I'll be copying has a .030" overbore, hypereutectic pistons, a Bullet cam, some bowl porting, stock valves and springs and a little port matching. It uses a 3-2-1 eBay header and an aftermarket 4 barrel manifold.

On the dyno it made 329 foot-pounds of torque @4,500 rpm and 304 HP @ 5,100rpm.

The only deviation is mine will have a lot more compression.

According to an on line calculator it should run mid 10's in a 1,800 pound dragster.

The 4.0 for this roadster will be almost stock.
 

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304 HP from 258" are some nice numbers. I would think the dragster will be more in the 1400# area and I really think low 10's for sure. I am really impressed with the valves & head shape. Are you going to deck the block to rase the compression?

Time to store the roadster & get back to finish work on the roadster pickup & the Bantam. I know you will be working on all three this winter, cause that's how you do it. Keep up the fine work.[cl[cl[cl
 
Added some 1" by 2" bracing in the door openings and welded in rocker panels. Glued a chunk of plywood on the inside of the firewall.
 

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Bolt on Bead

Used some 1/4" by 3/4" bar stock and beat it up with a flap disc until it resembled the bead on the cowl. Attached it with some #8 flat head screws. I can weld over the screw heads and sand them smooth until they're or noticeable or leave them exposed. I think this was a necessary addition to the doors.
 

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