Tech: Early heads on an 8BA Flathead

I know this has been covered....and I contributed to a thread on it a few years ago, but here is one way to do it, with pics.

First, you will need to plug a couple of holes on the block. Use the early headgaskets, and hold them up to the 8BA block, and it will be obvious which two it will need to be plugged.

Some people drill, tap, and put in a plug flush with the block, but I use a little steel expansion (freeze) plug on each side.

On one block I did, one of the smaller ones just tapped right in with a hammer, on the one I did today, I had to open up the holes a little with a drill...there are little differences from block to block.



You can see here on the passengers side why the water passage needs to be plugged!



The drivers side ends up under the head.

Now that the early heads are on, there is no provision to hold down the distributor.

The solution is easy...just drill a little hole in the timing cover, and tap it, and insert a little bolt!

I used this little aluminum bolt with a weird head on it because I figured it would be easier to get to with a little adjustable wrench, or even a pair of pliers.



The finished product!



If you use an MSD distributor, you can also make a little extension out of a flat piece of steel (I used a half of a spring shackle), and bolt it to the head, and it will extend over to the hold-down area of the MSD distributor.

 

To get the correct depth for distributer gear to mesh with cam gear you can also make an alum. spacer "ring".

 

nice man thanks for the info

 

Thanks for the info.

Kevin
Ooltewah Speed Shop

 

thanks, i am about ready to tackle this.

 

im curious,

Why put early heads on a late block?

 

Cos - maybe he's only got early heads!!!

 

Interesting. Having a flathead built now and just ask about this and if it is feasable. This answers all questions. Thanks for posting

 

(im curious,

Why put early heads on a late block?)

Lots of guys like the look of the water inlet at the center of the heads, more traditional ​

 

Thanks guys.

I had some Fentons on my Mercury flathead in my '29 truck, but after many set-backs trying to get the engine to fire. I discovered that there was some corrosion on the bottom of one of the heads, that was causing some combustion to blow into the water passage.

I had a new old stock set of early Sharps on the shelf, so I put those on the later block, and it fired right up!

This set was put on this engine, because it is going into a copy of an old bellytank racer that is going to the salt, and it needed to look like an earlier engine.

I do like the look of the earlier heads better, but 1949 heads look just about as traditional as 1948's!