331 Hemi Extended Block Modification

There's more information in this thread as well:

http://www.jalopyjournal.com/forum/showthread.php?t=118607&highlight=hemi+tech

 

This is how I'm going to do my hyd clutch on my '52 extended bell block: Mount a 1961 Chevy 3/4 ton truck clutch hyd slave cyl on the side of my notched bell (with the HH muncie plate)

I think this would be better than the hyd throwout brg. Easier to fix a leak, & easier to find a factory GM part.

I will use the hot heads adapter as a template for the notch on the extended bell


Top photo is a '55 331 (std bell)
Bottom photo: Where the slave cyl will bolt...Grey box will be the slave cyl.

 

Another sample pic...

 

I ran early Hemi's in my many FED's and used to buy & sell a lot of early Hemi parts. I used to buy parts and motors buy the garage full, and had bought a couple of 331's that were cut off long bell blocks. Both had been machined off flat and a 1/2 steel plate welded on, the plate was cut out in the 54 & later style and drilled and taped to the 54 & later pattern. My clutch can bolted right up as it did on all my other motors & if you didn't notice the weld it was as factory. If I was to do one today myself, I would make it Chevy pattern and even set it up for the Chevy starter. What I do wish is that I still had all my old 394 Olds parts & cut off one of those & updated it.

 

"Very unusual engine, it has adjustable LIFTERS that almost look like Flathead Ford gear..."

Early Chrysler hemis had a unique rebuildable hydraulic lifter. The hydraulic part comes out of the tappet. You can take them apart and clean them.

The secret is to take them apart one at a time, clean, and re***emble in a bath of kerosene. Clearance is so tight they will not fit together dry, and oil is too thick. They must be immersed in kerosene.

Do one at a time so you don't mix up the parts. Again, it is because the tolerances are so close the parts do not interchange. I believe they are fitted to 1/10,000 of an inch or less.

I have done this and they worked perfect.

If you do not want hydraulics you will need new lifters and new pushrods, the old lifters are longer than anything made today.

 

No reason to cut off the bell's anymore...
I think 73RR has an adapter on the drawing board for a Chevy auto (the only adapter that's n/a right now)

I went with the muncie adapter for mine because it needs to be a "hot-stepping hemi with a four on the floor"

 

I don't think there will much differance in lenght ether way you go long block and adapter or short and bellhousing.

 

Seriously? The extension is way longer than the adaptor.

 

George, the transmission will be the same distance from the engine, regardless if it's a long bell or short. I asked that question before. At least it is for a manual trans.

Not sure how the auto adapter will work

 

When a flywheel explodes at 6,000+ RPMs, a cast iron bellhousing is transformed into yet more shrapnel. That's why racing ***ociations specify steel containment.

jack vines

 

I'm gonna get one of these blankets for my extended bell hemi

http://www.goodvibesracing.com/DJSafetyTransmissionBlankets.htm

 

They would also specify a SFI approved steel flywheel.

 

If I was going through the process of modifying extended bell blocks, I would 1: include both the Mopar and GM bolt pattern, and 2: adjust the depth to compensate for the additional crankshaft length. (adding just a center register to the crank flange)
But in the end, it is just too much work. A short 331 block is not that hard to find.