Fitting a divers helmet dizzy to an 8BA.....

[Lawrie]

Gavin, another way to do it is to machine off the front of the 8ba cam,fit the earlier cam gears,machine 1 mm from the front of the cam cear,machine upma little disc with the early cam slot in and fit this under the 4 cam gear bolts that have 1 mm machined off the heads to clear,this works fine.
let me know if you want a pic.
Lawrie

[gavinnz]

Early gears it is. Oddly my two 8BA motors have each type of gear in them! One thrusting forward and one back... Very odd. So I have the correct crank gear and I just need to buy the new cam gear and that's sorted.

[gavinnz]

Originally Posted by Lawrie

Gavin, another way to do it is to machine off the front of the 8ba cam,fit the earlier cam gears,machine 1 mm from the front of the cam cear,machine upma little disc with the early cam slot in and fit this under the 4 cam gear bolts that have 1 mm machined off the heads to clear,this works fine.
let me know if you want a pic.
Lawrie

More then on way to skin a cat! Thanks for the info. Post a pic for sure.
One of the reasons I posted this was because I could not find any info on this conversion that was helpful so I hope others can find it in the future.

[Pete]

Lots of ways to convert back and forth. In the old days it was fairly common to machine the snout of a 32 steel cam for a bolt on gear. If you used a certain combination of distributor and front cover you just used a button. The buttons were only $3.95 in those days.

A little more time consuming but works fine, is converting an early core to 8ba type.

If you use straight cut gears you don't have to worry about cam thrust.

[Ol' Ron]

This is a real interesting thread on machine work. I'll be interesten in how the slot is milled. It's location is very important. I modify early cams by boring a 3/4" hole into the front of the cam. drilling a 1'8" hole into it to the oil hole. Then turn down the front of it to press on the distributor drive gear. I always use the early cam drive gears as the thrust is always to the block and eliminates cam walk.

[Ziggster]

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Very nice work. Wish I had a lathe. I'll be fitting a helmet dizzy to my C69 block as I also like the look. I hope the stock water pump pulleys clear it as I just purchased some new ones from Speedway.

[gavinnz]

Originally Posted by Ziggster

Very nice work. Wish I had a lathe. I'll be fitting a helmet dizzy to my C69 block as I also like the look. I hope the stock water pump pulleys clear it as I just purchased some new ones from Speedway.

Measure from the back face of the pump (ie what will be the front block face) to the mid point of your water pump pulley. Wide pulleys I assume? And will see how that lines up with the divers helmet dizzy on my engine.

[FlatheadTed]

Good post ,I have a NOS T5 cam I want to put in a 21 stud so I will be looking here for some pointers , Ted

[Ziggster]

Originally Posted by gavinnz

Measure from the back face of the pump (ie what will be the front block face) to the mid point of your water pump pulley. Wide pulleys I assume? And will see how that lines up with the divers helmet dizzy on my engine.

Yes, I have the wide pulley. Distance from pulley center to mounting surface is about 36 mm.

[gavinnz]

Originally Posted by Ziggster

Yes, I have the wide pulley. Distance from pulley center to mounting surface is about 36 mm.

That's good. That means your inner/ rearward crank pulley will be in hard against the front cover, which is good as the dizzy has most clearance there.

[gavinnz]

Picture..... iPad in one hand ruler in the other.... Pushed the iPad button with my nose!!! Lol

[blucar]

Don't want to throw cold water on all of this wonderful re-engineering of an antique ignition system, however, I think a very important point has been missed.. The engine in question is going into a boat, therefore the ignition and fuel systems must be marine approved for use on a boat, regardless if it is a vintage vessel or a new one.

[gavinnz]

Originally Posted by blucar

Don't want to throw cold water on all of this wonderful re-engineering of an antique ignition system, however, I think a very important point has been missed.. The engine in question is going into a boat, therefore the ignition and fuel systems must be marine approved for use on a boat, regardless if it is a vintage vessel or a new one.

In the USA you would be right but in New Zealand as long as you have a life jacket for everybody on board and navigation lights to suit your size and speed, anything goes. Just build it launch it and have fun.

[gavinnz]

Having said that anything goes, I do not want a high octane Viking funeral myself!
So I am maranising the engine components as needed.

[Ziggster]

Originally Posted by gavinnz

Picture..... iPad in one hand ruler in the other.... Pushed the iPad button with my nose!!! Lol

Thanks. My block has been at the machinist since last August. Had to balance my iPad a few times to take pics as well. Lol.