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Modified Spider - Allow access to flywheel bolts

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Modified Spider - Allow access to flywheel bolts

Postby diablo » Fri Feb 20, 2015 3:06 pm

IMG_4002.JPG
Spider with compression ring superimposed
IMG_4002.JPG (432.2 KiB) Viewed 2267 times


IMG_4003.JPG
Spider with access half moon machined out
IMG_4003.JPG (398.5 KiB) Viewed 2267 times
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Re: Modified Spider - Allow access to flywheel bolts

Postby diablo » Sat Feb 21, 2015 12:34 pm

Please note - these are my opinions

The PCD of bolts 33.5, therefore centre of bolt is 1.75 mm in from edge of hub ( central hole).

The radius of the access half moon, can be increased to 1/2" and more to cater for ARP bolts if required. It is also possible to increase size of hub (central hole) from 30 mm to 45 mm thereby allowing unobstructed access to all flywheel bolts for inspection or torqueing/replacement. This would be my preferred solution for obvious reasons.

The main advantage of the ARP bolt is the larger flange that coupled with equally sized nordlock washers would effectively spread load on compression ring and flywheel. The image shows a 1/2" radius half moon ...

My work is based on the later stator (12 pole). Earlier engines have the 10 pole stator which had a smaller hub. Please ensure that any machining is carefully planned before attempting to modify engines fitted with the early 10 pole stator.

IMG_4006.JPG
1/2" half moon to access ARP or Socket Head bolts
IMG_4006.JPG (398.5 KiB) Viewed 2246 times
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Modified Spider (CAMIT) - Allow access to flywheel bolts

Postby diablo » Mon Aug 24, 2015 6:30 am

The biggest advantage of increasing the size of the hole on the spider is that you can check flywheel torque in situ.

This is a relativelly easy process, however it does require a certain amount of skill in hadling power tools. If you have a CAMIT alternator mod fitted to your engine and are not using a Vacuum pump, you can increase the size of the hole on the spider to 50mm. You can still increase size of hole if you have a pump but will need to remove the vacuum pump to check torque of flywheel bolts.

The size of the hole can be increased using a hole saw or a lathe with a boring tool.


IMG_4270.JPG
CAMit spider with larger bored out hole for easy access to flywheel bolts
IMG_4270.JPG (316.42 KiB) Viewed 1996 times
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