SBF flywheel on an inline six (possible?)

Ive read/looked at this tech article many times, and I've been wondering what do these mods to the flywheel/flex plate look like?

[url=http://www.fordsix.com/V8Bell.php:3rv7r8r5 said:

Adapt a V8 Bellhousing[/url]":3rv7r8r5]6. The V8 flexplate needs attention too. Have your machinist drill new crank holes onto the V8 flexplate using the I6 enforcer ring or the I6 flexplate as a template. The counterweight needs to be removed. Then re-balance the flexplate to zero imbalance.

Click to expand...

If I used parts (flywheel/flexplate) for a 250 instead of a SBF, would I still need to rebalance?

thanks in advance,
-ron

no you wouldnt since the 250 is internally balanced. you can also use a 240/300 flexplate/flywheel as well if you cant find a 250 wheel.

The 250 can use a SBF bellhousing and flywheel that is zero balanced. The bolt patterns on the 250/SBF flywheels are identical.

The 200 crank/flywheel has a different bolt pattern than the 250/SBF. That's why you have to redrill the 250/SBF flywheel to bolt onto the 200 crank.

Hope this helps.

Had anybody on here done the redrilling of a 250/240/300/SBF flywheel or flex plate? And if so was there anything special to be aware of? And how long have you been using it?
I had asked about rebalancing a 250/240/300 flywheel or flex plate because I wasn't sure if drilling a hole or two th the center of it was enough to throw off the balance or not.

To be clear, I want to use a SBF (250/240/300) flywheel or flex plate on a small six (144/170/200)

drilling the holes is not going to affect the balance of the wheel. just make sure that the bolt pattern is properly centered.

Sooo I loves me some pictures.. I went home and spun the 250 short block around and the 170 long block. Both had previously been used with automatics, so flexplates on both of them.


spun out the bolts and took off the flexplates, overlayed the 170 reinforcement ring over the center of the 250 flex plate.

It looks like all six holes are off by just a little bit..

So I assume that when the new holes are drilled, they are evenly spaced between the original holes?

Or do people simply oval the holes a little bit?

One other thing, if none of you have ever seen this before.
8.5" Early Flywheel.pdf
The PDF contains a fully dimensioned 8.5" Flywheel. The PDF has a ton of information in it. Including this lovely nugget.
This picture is as if you were looking at the flywheel from the clutch side.

There is a lot more info in the PDF itself.

You should be sure to thank SoCar72. Several years when he performed his T5 installation;
T5 Crossmember for 63 Falcon - Pix
He also created a couple documents with full dimensions, another one have never seen..
2.77 Early L6 Bellhousing.pdf

I would think that you could have the holes slotted depending on how much difference there is, think of how they did the unilug wheels. Or as you said the holes could be re drilled between the old ones

Edit the holes are also off set drilled so that the flywheel / flex plate only bolts on one way I have not compared the 200 and smaller engines to a 250 but I am fairly sure that Ford also off set drilled them the same way as they did on every other engine.