Mix match 8Ba & 59A pulley/distributors etc

[Jeep09]

Hi,
I have a 8BA motor. It has a Crower 59A style camshaft. I want to keep this .

Is there an adapter/fix to use a 8BA distributor in this configuration?

[Ken/Alabama]

https://www.speedwaymotors.com/Offen...ear,25039.html

[Bored&Stroked]

Couple very important things to know about that adapter:

1) If you're running a 59A style cam, you'll probably find that when you put the stock bolts into this adapter, that they might hit the timing cover. When this happens a bunch of metal gets ground off and thrown down into the oil. You may need to modify the adapter to use different fasteners with countersunk heads on them. Something like this:

https://www.mcmaster.com/products/sc...head-screws-9/

2) IMPORTANT: Stock 49-53 cams had an oil-pressure port/hole in the front bearing journal - that fed positive oil pressure to the front of the snout of the cam. The front surface of the cam is a "thrust surface" - if you don't provide a reliable amount of oil-pressure, then it will gall over time. Again - more metal filings in your oil and a cam that is now walking back and forth.

a) CAM: You need to look at a 49-53 CAM, see what was done with the pressurized oil port and replicate it with your 59x type cam. It can't be done with the cam in the engine! You have to drill the cam in two places ---> one in the journal and another through the front of it to hit the journal oil hole.

b) Adapter: It needs to be drilled to allow pressurized oil to reach the front thrust surface. You also want to make sure there is a good fitment on the backside of it (such that you don't have a big pressure leak between the 59X cam front surface and the back of the adapter.

The above usually requires some machine tools (mill, lathe, etc) and knowledge to get it right. If it is not right, then you'll most likely cause damage to the engine.

It is a SHAME that folks like Speedway sell products like this without instructions and warnings like the above.

Best of luck!

B&S

[Jeep09]

Thanks' for the input. I have picked up Motor City Flathead (8BA) motor with a few parts robbed off. I would like to use the 8BA front items, water pumps & a pass side distributor as I already have these items. Thanks for this valuable input

[Newc]

There was a past post on this subject [search]- a failure to oil the 'snout' using an adapter. Newc

[outlaw]

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Originally Posted by Bored&Stroked

Couple very important things to know about that adapter:

1) If you're running a 59A style cam, you'll probably find that when you put the stock bolts into this adapter, that they might hit the timing cover. When this happens a bunch of metal gets ground off and thrown down into the oil. You may need to modify the adapter to use different fasteners with countersunk heads on them. Something like this:

https://www.mcmaster.com/products/sc...head-screws-9/

2) IMPORTANT: Stock 49-53 cams had an oil-pressure port/hole in the front bearing journal - that fed positive oil pressure to the front of the snout of the cam. The front surface of the cam is a "thrust surface" - if you don't provide a reliable amount of oil-pressure, then it will gall over time. Again - more metal filings in your oil and a cam that is now walking back and forth.

a) CAM: You need to look at a 49-53 CAM, see what was done with the pressurized oil port and replicate it with your 59x type cam. It can't be done with the cam in the engine! You have to drill the cam in two places ---> one in the journal and another through the front of it to hit the journal oil hole.

b) Adapter: It needs to be drilled to allow pressurized oil to reach the front thrust surface. You also want to make sure there is a good fitment on the backside of it (such that you don't have a big pressure leak between the 59X cam front surface and the back of the adapter.

The above usually requires some machine tools (mill, lathe, etc) and knowledge to get it right. If it is not right, then you'll most likely cause damage to the engine.

It is a SHAME that folks like Speedway sell products like this without instructions and warnings like the above.

Best of luck!

B&S

Dale, do you happen to have any pictures or diagrams on doing the modifications that you have recommended here? Pictures speak a thousand words & make it a lot easier to understand for any of us wanna be machinist types that like to do as much on our own as possible.

[Ken/Alabama]

Originally Posted by Bored&Stroked

Couple very important things to know about that adapter:

1) If you're running a 59A style cam, you'll probably find that when you put the stock bolts into this adapter, that they might hit the timing cover. When this happens a bunch of metal gets ground off and thrown down into the oil. You may need to modify the adapter to use different fasteners with countersunk heads on them. Something like this:

https://www.mcmaster.com/products/sc...head-screws-9/

2) IMPORTANT: Stock 49-53 cams had an oil-pressure port/hole in the front bearing journal - that fed positive oil pressure to the front of the snout of the cam. The front surface of the cam is a "thrust surface" - if you don't provide a reliable amount of oil-pressure, then it will gall over time. Again - more metal filings in your oil and a cam that is now walking back and forth.

a) CAM: You need to look at a 49-53 CAM, see what was done with the pressurized oil port and replicate it with your 59x type cam. It can't be done with the cam in the engine! You have to drill the cam in two places ---> one in the journal and another through the front of it to hit the journal oil hole.

b) Adapter: It needs to be drilled to allow pressurized oil to reach the front thrust surface. You also want to make sure there is a good fitment on the backside of it (such that you don't have a big pressure leak between the 59X cam front surface and the back of the adapter.

The above usually requires some machine tools (mill, lathe, etc) and knowledge to get it right. If it is not right, then you'll most likely cause damage to the engine.

It is a SHAME that folks like Speedway sell products like this without instructions and warnings like the above.

Best of luck!

B&S

I’ve never used one myself but what happens if you use the timing gears for the 59A that thrust the cam towards the block and not the front cover like the 8BA. ?

[Ol' Ron]

The 59 early block has the cam thrust back to the block. Considering all the oil leaking from the front main I doubt the hole in the nose of the adapter is necessary in a street engine. I', used several of them to run the loadamit distributor on the 5 engine.
Gramps

[Jeep09]

I will change my timing gears to 8BA style to accommodate the thrust.

[Ken/Alabama]

Originally Posted by Jeep09

I will change my timing gears to 8BA style to accommodate the thrust.

I would change to the 59A gears .

[Bored&Stroked]

I'm with Ken and Ron . . . I normally run the earlier set of crank/cam timing gears and keep the thrust toward the block. Also, something you really need to check is the following:

1) With the block up on a stand and cam bearings in it, pull the rear oil-pump drive gear cover. You need access to the rear of the cam to check the thrust.
2) Put the cam in the block with the newly mounted adapter on it. (don't put any springs/valves in as of yet).
3) Put the timing cover on with a gasket.
4) Put a dial-indicator on the rear of the cam. You'll need a magnetic base to give you a decent mounting point.
5) Now, with everything bolted up, push the cam back/forth and see first of all that you have some thrust clearance - and secondly what it is. I usually shoot for about .004, though it can be up to about .008. You don't want zero thrust clearance, or you risk burning the front of the cam and/or the thrust surface against the block. You also don't want too much or the cam can move back/forth depending on whether or not you're accelerating or decelerating, and this causes your timing to fluctuate.
6) Original timing cover gaskets were about .008 thick, some of the repops are way too thick (like some I've seen from Speedway - at about .016). When you use too thick of a gasket - it can cause your clearances to get quite large.
7) Sometimes one has to run no gasket - and just use RTV to seal the timing cover.
8) Sometimes one has to screw with the adapter and machine it to set the clearances.

The reason I'm mentioning all of this is because I have no faith in the quality control and/or dimensional accuracy of these adapters. They may be dead nuts correct and your clearances will be good . . . or maybe not.

The important thing is that you need to check cam thrust (on any flathead engine).

Best of luck!
B&S

[Ken/Alabama]

Originally Posted by Bored&Stroked

I'm with Ken and Ron . . . I normally run the earlier set of crank/cam timing gears and keep the thrust toward the block. Also, something you really need to check is the following:

1) With the block up on a stand and cam bearings in it, pull the rear oil-pump drive gear cover. You need access to the rear of the cam to check the thrust.
2) Put the cam in the block with the newly mounted adapter on it. (don't put any springs/valves in as of yet).
3) Put the timing cover on with a gasket.
4) Put a dial-indicator on the rear of the cam. You'll need a magnetic base to give you a decent mounting point.
5) Now, with everything bolted up, push the cam back/forth and see first of all that you have some thrust clearance - and secondly what it is. I usually shoot for about .004, though it can be up to about .008. You don't want zero thrust clearance, or you risk burning the front of the cam and/or the thrust surface against the block. You also don't want too much or the cam can move back/forth depending on whether or not you're accelerating or decelerating, and this causes your timing to fluctuate.
6) Original timing cover gaskets were about .008 thick, some of the repops are way too thick (like some I've seen from Speedway - at about .016). When you use too thick of a gasket - it can cause your clearances to get quite large.
7) Sometimes one has to run no gasket - and just use RTV to seal the timing cover.
8) Sometimes one has to screw with the adapter and machine it to set the clearances.

The reason I'm mentioning all of this is because I have no faith in the quality control and/or dimensional accuracy of these adapters. They may be dead nuts correct and your clearances will be good . . . or maybe not.

The important thing is that you need to check cam thrust (on any flathead engine).

Best of luck!
B&S

Yes!

[Ol' Ron]

B&S has some good advice, I also found that some of the adapters had alot of runout. I wouldn't except more than .004", Remembet it drives the distributor/
G