Mag T1 case - how big is practical?

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petew
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Mag T1 case - how big is practical?

Post by petew » Tue Apr 11, 2017 7:28 am

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.

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Chip Birks
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Re: Mag T1 case - how big is practical?

Post by Chip Birks » Tue Apr 11, 2017 8:14 am

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
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Re: Mag T1 case - how big is practical?

Post by farmer » Tue Apr 11, 2017 1:01 pm

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

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petew
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Re: Mag T1 case - how big is practical?

Post by petew » Tue Apr 11, 2017 5:09 pm

I think I see why people go T4.

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andy198712
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Re: Mag T1 case - how big is practical?

Post by andy198712 » Mon Apr 17, 2017 11:11 am

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 (££)

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Chip Birks
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Re: Mag T1 case - how big is practical?

Post by Chip Birks » Mon Apr 17, 2017 11:16 am

A TW 92 motor would probably be great too.

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andy198712
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Re: Mag T1 case - how big is practical?

Post by andy198712 » Wed Apr 19, 2017 3:47 am

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

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Re: Mag T1 case - how big is practical?

Post by madmike » Thu Apr 20, 2017 9:06 am

I've done a few :lol: 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)

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Chip Birks
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Re: Mag T1 case - how big is practical?

Post by Chip Birks » Thu Apr 20, 2017 10:19 am

andy198712 wrote:
Wed Apr 19, 2017 3:47 am
Good shout,
Those are the relitily easy stroker builds I'd say.
Are you building and clearancing by hand?
Me? Or Pete?

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andy198712
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Re: Mag T1 case - how big is practical?

Post by andy198712 » Thu Apr 20, 2017 4:00 pm

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

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petew
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Re: Mag T1 case - how big is practical?

Post by petew » Sat Apr 22, 2017 11:05 pm

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

Bruce2
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Re: Mag T1 case - how big is practical?

Post by Bruce2 » Mon Apr 24, 2017 2:20 am

petew wrote:
Sat Apr 22, 2017 11:05 pm
Most like with a dremel.
That will take months. Get a die grinder.

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Re: Mag T1 case - how big is practical?

Post by Bruce2 » Mon Apr 24, 2017 2:27 am

farmer wrote:
Tue Apr 11, 2017 1:01 pm
. 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.

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petew
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Re: Mag T1 case - how big is practical?

Post by petew » Mon Apr 24, 2017 6:48 pm

Bruce2 wrote:
Mon Apr 24, 2017 2:20 am
petew wrote:
Sat Apr 22, 2017 11:05 pm
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
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Re: Mag T1 case - how big is practical?

Post by Bruce2 » Wed Apr 26, 2017 12:46 am

That's why you need an electric die grinder.

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