Mag T1 case - how big is practical?

[petew]

So I've got a late bus T1 motor kicking around in my shed. Been thinking for some time it would be cool to really go big. Not a race motor, but a really torquey street motor with maybe a little boost. Something I could use for the odd autokhana, but mostly just cruise with. No big revs, no crazy launches, reliable, streetable, useful power and torque.

What is the maximum crank could you put in it before the case was too fragile?

I assume 94s are the limit bore-wise?

P.s. I've just read the case clearancing thread.

[Chip Birks]

I've seen up to 90mm crammed into mag cases in the past. Tight fit, probably fairly difficult to build compared to an average 82mm build.

[farmer]

Big within reason - 2386, even 2442, but you will need to buy expensive rods to make things clear inside. 90 mm stroke has been done every now and then, maybe especially Berni Bergmann, for sand dragsters and RV´s. I don´t like them. Too weak rod journals and too large risk of the crank flexing.
2275 or 2386 gets my vote.

t

[petew]

I think I see why people go T4.

[andy198712]

2110 is what I did and it was okay hand clearance.
2332 is pretty bolt together I think, just wondering if you'll get a 90.5 motor to be more happy in your heat? Or SS pistons (££)

[Chip Birks]

A TW 92 motor would probably be great too.

[andy198712]

Good shout,
Those are the relitily easy stroker builds I'd say.
Are you building and clearancing by hand?

[madmike]

I've done a few loved the torque of the 2332 with w120 cam, short rod(Porsche), I did have to clearance the piston skirts,,,CB 044 42x37.5 with only 44 webers very streetable and ran cool too (stock dog house)

[Chip Birks]

Good shout,
Those are the relitily easy stroker builds I'd say.
Are you building and clearancing by hand?

Me? Or Pete?

[andy198712]

Good call on the 92TW, And is Pete clearing by hand

[petew]

Well I already have the case, so I guess the answer is "yes", I'd be hand clearing. Most like with a dremel.

[Bruce2]

Most like with a dremel.

That will take months. Get a die grinder.

[Bruce2]

. Too weak rod journals and too large risk of the crank flexing.

I think that's a myth from year ago.
For the last 20+ years VW drag racers have been using 2" Chev journals on long stroke cranks. If flexing was a problem, they would have abandoned that journal years ago. Instead, they are moving towards Honda journals, which are even smaller.
I know one drag racer that always built 90x94 engines using a stock Mg case. To fit the 90mm crank, you are using Chev journals. This means it is easier to clearance the case than if you try to build it with an 84 stroke VW journal.

[petew]

Most like with a dremel.

That will take months. Get a die grinder.

Got one. What don't have is an enormous compressor that will drive it.

[Bruce2]

That's why you need an electric die grinder.