Hi Andy,
I believe the inner CV joint bolts are the weakest point outside the trans. As for inside- I'm not sure.
The T2 CV's have the same diameter spline as the Bug, and the mounting flange PCD is bigger, the same as all the Porsches (?). The axles from a steel armed 944 are bigger in diameter and the same length as the Bug. The problem is the smaller PCD on the T1 trans. output flanges. The T2 trans has a bigger diff. and output flanges that will not fit in the T1 case. The Trekker/T181 trans is IRS T1 with T2 PCD output flanges. 'probably for the extra abuse the military vehicles had to cope with (?). I don't know the dia./length of the T181 axles.
Maybe you could specify T181 output flanges for your 'built' trans' and use the early 944 axles. This would make a much stronger set-up.
I too want to drag my '03- as well as drive it everyday! I'm going Porsche5- :silly: for the challenge!
I'm also looking into a 'built' T2 trans' with more appropriate 'ratios. I've got the Ally 'arms- nice, shiny and light. Bigger PCD CV's and longer, stronger axles.
Also worth mentioning is that most T181/182's had LSD! As do some '03 trans, I'm surprised that no-one raves on about these tranny's for IRS drag applications. 'Must be a reliability reason for this. 'Onewheel' burn-outs were common at Bug Jam RWYB
I've not seen the insides of a 'chewed-up' T1 IRS trans'- not yet anyway!
One thing's for sure, I'm gonna need a better trans too. My trans' doesn't have 2 side plates so mods are probably worthless in the long run.
Matt