Saginaw for a serpentine IDI: brainstorming

[Gary Lewis]

But, even if there is no height difference in the part that bolts to the head, we don't know that there aren't other differences. Like a slight difference in an angle or other dimension that makes the mounting point for the power steering pump different. Right?

So, if we assume that the head is a good reference point, then why not measure from the head mounting point to the power steering pump mounting point?

I know you have something in mind, but I'm missing it. Sorry!

And, I missed the hole size diff. Yes, I remember reading about that. But, in reality what we are trying to do is figure out how Jonathan can bolt a Saginaw to his IDI when there was no Sag bracket for the IDI.

[ArdWrknTrk]

But, even if there is no height difference in the part that bolts to the head, we don't know that there aren't other differences. Like a slight difference in an angle or other dimension that makes the mounting point for the power steering pump different. Right?

So, if we assume that the head is a good reference point, then why not measure from the head mounting point to the power steering pump mounting point?

I know you have something in mind, but I'm missing it. Sorry!

You're much better at this than me.

I will follow along and see what you come up with.

[Gary Lewis]

You're much better at this than me.

I will follow along and see what you come up with.

There's where we differ. But let's see what I come up with.

[ArdWrknTrk]

And, I missed the hole size diff. Yes, I remember reading about that. But, in reality what we are trying to do is figure out how Jonathan can bolt a Saginaw to his IDI when there was no Sag bracket for the IDI.

I'm not sure how the C2 bracket mounts to an IDI.

It would seem best to measure the mounted C2's pulley plane to some fixed point and then cut down/space the Saginaw pump -with adapter- to make it work.

 

[Gary Lewis]

I'm not sure how the C2 bracket mounts to an IDI.

It would seem best to measure the mounted C2's pulley plane to some fixed point and then cut down/space the Saginaw pump -with adapter- to make it work.

I've been assuming that the pulleys have to be in the same plane. Right?

So, if I can determine how much further back a Sag mounts vs a C2, then Jonathan can space a Sag that far on a C2 bracket and know the pulley will be in the right plane. Yes?

[ArdWrknTrk]

I've been assuming that the pulleys have to be in the same plane. Right?

So, if I can determine how much further back a Sag mounts vs a C2, then Jonathan can space a Sag that far on a C2 bracket and know the pulley will be in the right plane. Yes?

Is the bracket, or crankshaft pulley the same for an IDI *and* a 460?

I don't presume to know.

I was trying to point out that in the case of a carbureted 460 there definitely *is* a variable in the cylinder head to cast mounting bracket distance. (although the cast bracket looks very similar)

So, maybe the water pump face (where there is no spacer, standoff, or boss bolted on) would make a better datum?

It also seems like it would be easier to measure from a fixed point on the water pump to the inside edge of the belt with a simple ruler.

 

[Gary Lewis]

Is the bracket, or crankshaft pulley the same for an IDI *and* a 460?

I don't presume to know.

I was trying to point out that in the case of a carbureted 460 there definitely *is* a variable in the cylinder head to cast mounting bracket distance. (although the cast bracket looks very similar)

So, maybe the water pump face (where there is no spacer, standoff, or boss bolted on) would make a better datum?

It also seems like it would be easier to measure from a fixed point on the water pump to the inside edge of the belt with a simple ruler.

Won't the inside edge of the belt be the same for a C2 as a Sag if the engine is the same? All the other pulleys don't change so the power steering pulley can't either.

Since the belt/running surfaces of the pulleys should be in the same position, and since the pumps and pulleys are used as a team, I was thinking that the real question becomes where the Sag mounts with respect to the C2.

If I measure from any reference point, like the head or the water pump, to the mounting position of the power steering pumps we will know the delta. Just move the Sag back that amount on any engine's C2 bracket and the pulley should be in the right position.

I must be missing something. Or saying this poorly. Perhaps a rudimentary drawing?

[ArdWrknTrk]

Won't the inside edge of the belt be the same for a C2 as a Sag if the engine is the same? All the other pulleys don't change so the power steering pulley can't either.

Since the belt/running surfaces of the pulleys should be in the same position, and since the pumps and pulleys are used as a team, I was thinking that the real question becomes where the Sag mounts with respect to the C2.

If I measure from any reference point, like the head or the water pump, to the mounting position of the power steering pumps we will know the delta. Just move the Sag back that amount on any engine's C2 bracket and the pulley should be in the right position.

I must be missing something. Or saying this poorly. Perhaps a rudimentary drawing?

The pulley is obviously different (shaft size) but with the multitude of Saginaw variations, do we know if the shaft has the same 'stickout' or the pulley has more or less offset?

I get where you're coming from, but apples to apples is tough to tell when the tree has been grafted.

[Gary Lewis]

The pulley is obviously different (shaft size) but with the multitude of Saginaw variations, do we know if the shaft has the same 'stickout' or the pulley has more or less offset?

I get where you're coming from, but apples to apples is tough to tell when the tree has been grafted.

Good analogy.

As for the pump, all I can do is give Jonathan the dimensions of my pumps. (I just realized I have the one I rebuilt for Dad's truck which I can also measure.) And, hopefully that with the source of the pump, like the year and model of the vehicle the pump came from, he can get the same pump and know it'll fit.

[Ford F834]

Won't the inside edge of the belt be the same for a C2 as a Sag if the engine is the same? All the other pulleys don't change so the power steering pulley can't either.

Since the belt/running surfaces of the pulleys should be in the same position, and since the pumps and pulleys are used as a team, I was thinking that the real question becomes where the Sag mounts with respect to the C2.

If I measure from any reference point, like the head or the water pump, to the mounting position of the power steering pumps we will know the delta. Just move the Sag back that amount on any engine's C2 bracket and the pulley should be in the right position.

I must be missing something. Or saying this poorly. Perhaps a rudimentary drawing?

Gary, since I am using the C2 bracket, and my goal is to keep the pulley in its current position relative to the bracket, my plan is to carefully measure the space between the bracket face and the back of the pulley and try to replicate that with spacers and how far I press the pulley on. The reason I asked about the distance between the block/head surface and the surface where the pump sits is just to anticipate whether a lot of spacing may be needed. Remember my original article where the guy had to space the pump aft about 5/8"? I'm just wondering why the difference... totally different bracket than either of ours, I know... but same plan of putting a Saginaw in a C2 bracket. I don't need an exact measurement, I just want to have some clue what I'm building so I can design it right.