Auto engine bolt patterns

Hello

Does anyone have any experience getting the bolt pattern off the
transmission side of an auto engine?

I'm building a PSRU, and I need to make the plate that bolts to the engine.
The rest of the pattern is generic, but that is engine specific.

I have tried several ways of measuring the holes in the block, but I'm sure
I can't get accuracy better than 1/10 inch or so. Surly engineering drawings
for these patterns are available somewhere.

On Sun, 17 Oct 2004 17:04:26 -0800, "Ron Webb"
wrote:

Hello

Does anyone have any experience getting the bolt pattern off the
transmission side of an auto engine?

I'm building a PSRU, and I need to make the plate that bolts to the engine.
The rest of the pattern is generic, but that is engine specific.

I have tried several ways of measuring the holes in the block, but I'm sure
I can't get accuracy better than 1/10 inch or so. Surly engineering drawings
for these patterns are available somewhere.

Here's an idea that I've had for some time. Machine some bolts that
fit the threads of the block into points. Thread them into the block
such that the pointed end is facing out. Place an aluminum sheet (at
least 1/4 thick) over the engine and tap each bolt location with a
hammer. This center punches the bolt's location.

Take the template over to your drill press and drill out the center
punched holes. That should be very accurate.

Corky Scott

"Ron Webb" wrote in message ...
Hello

Does anyone have any experience getting the bolt pattern off the
transmission side of an auto engine?

I'm building a PSRU, and I need to make the plate that bolts to the engine.
The rest of the pattern is generic, but that is engine specific.

I have tried several ways of measuring the holes in the block, but I'm sure
I can't get accuracy better than 1/10 inch or so. Surly engineering drawings
for these patterns are available somewhere.

Just a thought but how about getting a new gasket that fits and using
it to transfer the holes??

Harry K

"Corky Scott" wrote in message
...
On Sun, 17 Oct 2004 17:04:26 -0800, "Ron Webb"
wrote:

Hello

Does anyone have any experience getting the bolt pattern off the
transmission side of an auto engine?

I'm building a PSRU, and I need to make the plate that bolts to the
engine.
The rest of the pattern is generic, but that is engine specific.

I have tried several ways of measuring the holes in the block, but I'm
sure
I can't get accuracy better than 1/10 inch or so. Surly engineering
drawings
for these patterns are available somewhere.

Here's an idea that I've had for some time. Machine some bolts that
fit the threads of the block into points. Thread them into the block
such that the pointed end is facing out. Place an aluminum sheet (at
least 1/4 thick) over the engine and tap each bolt location with a
hammer. This center punches the bolt's location.

Take the template over to your drill press and drill out the center
punched holes. That should be very accurate.

Corky Scott

Thanks guys.

Both good suggestions.

But the one dimension that must be DEAD accurate is the position of the
center of the crank relative to the dowel pins.. Neither suggestion is going
to solve this one without taking the engine apart. I am working on a new
aluminum Ford 4.6L V8 short block, so the entire lower end is already in
place.

Just a thought,
Can you use a compass to first get the proper radius of the bolt pattern
from the centerline of the block (Yeah a pretty big compass) , then use a
smaller compass to measure centerline of bolt to bolt? If you get the radius
layout right the pattern should be perfect...or as close to it as mere
mortal man can be! hee hee

Patrick
"Ron Webb" wrote in message
...

"Corky Scott" wrote in message
...
On Sun, 17 Oct 2004 17:04:26 -0800, "Ron Webb"
wrote:

Hello

Does anyone have any experience getting the bolt pattern off the
transmission side of an auto engine?

I'm building a PSRU, and I need to make the plate that bolts to the
engine.
The rest of the pattern is generic, but that is engine specific.

I have tried several ways of measuring the holes in the block, but I'm
sure
I can't get accuracy better than 1/10 inch or so. Surly engineering
drawings
for these patterns are available somewhere.

Here's an idea that I've had for some time. Machine some bolts that
fit the threads of the block into points. Thread them into the block
such that the pointed end is facing out. Place an aluminum sheet (at
least 1/4 thick) over the engine and tap each bolt location with a
hammer. This center punches the bolt's location.

Take the template over to your drill press and drill out the center
punched holes. That should be very accurate.

Corky Scott

Thanks guys.

Both good suggestions.

But the one dimension that must be DEAD accurate is the position of the
center of the crank relative to the dowel pins.. Neither suggestion is
going
to solve this one without taking the engine apart. I am working on a new
aluminum Ford 4.6L V8 short block, so the entire lower end is already in
place.

In article ,
says...


"Corky Scott" wrote in message
.. .
On Sun, 17 Oct 2004 17:04:26 -0800, "Ron Webb"
wrote:

Hello

Does anyone have any experience getting the bolt pattern off the
transmission side of an auto engine?

I'm building a PSRU, and I need to make the plate that bolts to the
engine.
The rest of the pattern is generic, but that is engine specific.

I have tried several ways of measuring the holes in the block, but
I'm
sure
I can't get accuracy better than 1/10 inch or so. Surly engineering
drawings
for these patterns are available somewhere.

Here's an idea that I've had for some time. Machine some bolts that
fit the threads of the block into points. Thread them into the bloc
k
such that the pointed end is facing out. Place an aluminum sheet (a
t
least 1/4 thick) over the engine and tap each bolt location with a
hammer. This center punches the bolt's location.

Take the template over to your drill press and drill out the center
punched holes. That should be very accurate.

Corky Scott

Thanks guys.

Both good suggestions.

But the one dimension that must be DEAD accurate is the position of th
e
center of the crank relative to the dowel pins.. Neither suggestion is
going
to solve this one without taking the engine apart. I am working on a n
ew
aluminum Ford 4.6L V8 short block, so the entire lower end is already
in
place.

How about working from the transmission/bellhouseing assembly instead?
Put transfer punches in the holes as suggested. Machine a short
extension for the transmission shaft to transfer its location to your
pattern.

"Ron Webb" wrote in message
...

But the one dimension that must be DEAD accurate is the position of the
center of the crank relative to the dowel pins.. Neither suggestion is
going
to solve this one without taking the engine apart. I am working on a new
aluminum Ford 4.6L V8 short block, so the entire lower end is already in
place.

I'm thinking of a jig for this. Insert something in the back of the crank
which will extend the centerline of the shaft past the plane of the dowel
pins. Something like the alignment spuds used to center a clutch plate.

Make a block with a hole in it to slip over the crank extension. This block
should have adjustable arms on it (equal to the number of dowels in the bell
housing. Those arms could be slotted like the arms on an engine stand.
Assemble the whole mess so that the ends of the arms are located on the
dowels and tighten it down. Slip it back off the crank extension and you
have a pattern. For one-time use, you could just weld it together from
scrap.

Wish I could draw it with a pencil.

Rich S.

Ron Webb wrote:

"Corky Scott" wrote in message
...

On Sun, 17 Oct 2004 17:04:26 -0800, "Ron Webb"
wrote:


Hello

Does anyone have any experience getting the bolt pattern off the
transmission side of an auto engine?

I'm building a PSRU, and I need to make the plate that bolts to the

engine.

The rest of the pattern is generic, but that is engine specific.

I have tried several ways of measuring the holes in the block, but I'm

sure

I can't get accuracy better than 1/10 inch or so. Surly engineering

drawings

for these patterns are available somewhere.

Here's an idea that I've had for some time. Machine some bolts that
fit the threads of the block into points. Thread them into the block
such that the pointed end is facing out. Place an aluminum sheet (at
least 1/4 thick) over the engine and tap each bolt location with a
hammer. This center punches the bolt's location.

Take the template over to your drill press and drill out the center
punched holes. That should be very accurate.

Corky Scott


Thanks guys.

Both good suggestions.

But the one dimension that must be DEAD accurate is the position of the
center of the crank relative to the dowel pins.. Neither suggestion is going
to solve this one without taking the engine apart. I am working on a new
aluminum Ford 4.6L V8 short block, so the entire lower end is already in
place.

Take the block to a machine shop with a CMM and they'll have your
dimensions in no time.


Matt

On Sun, 17 Oct 2004 17:04:26 -0800, "Ron Webb"
wrote:

Hello

Does anyone have any experience getting the bolt pattern off the
transmission side of an auto engine?

I'm building a PSRU, and I need to make the plate that bolts to the engine.
The rest of the pattern is generic, but that is engine specific.

I have tried several ways of measuring the holes in the block, but I'm sure
I can't get accuracy better than 1/10 inch or so. Surly engineering drawings
for these patterns are available somewhere.


It is called Technology Transfer or Tek-Connect or some such depending
on manufacturer. If you or someone you know belongs to the Specialty
Equipment Market Association www.sema.org , the manufacturing specs
are available. That is how you are able to pick up a brake rotor at
your local auto parts and it will fit.

Thanks Andy.

That's the information I was looking for.

Course, not being a member kinda puts a damper on things. Membership looks
to cost about $350/yr, so I guess I'll just measure things as best I can.

I knew the info was out there - I suppose I shoulda guessed it wasn't free!
;^}


"Andy Asberry" wrote in message
...
It is called Technology Transfer or Tek-Connect or some such depending
on manufacturer. If you or someone you know belongs to the Specialty
Equipment Market Association www.sema.org , the manufacturing specs
are available. That is how you are able to pick up a brake rotor at
your local auto parts and it will fit.