MRP Flywheel Bolt Options

yabaiani
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MRP Flywheel Bolt Options

Postby yabaiani » Wed May 06, 2020 4:18 pm

So I bought a new flywheel from MRP, but it seems the 4AG ARP flywheel bolts don’t fit. Chatted with Barry and he said they made it thinner and that the bolts need to be 3mm smaller. With that said, this is the flywheel bolts for the 4AG (https://www.jegs.com/i/ARP/070/203-2802/10002/-1), but it’s too long.

Does anyone know an alternative that may work?

totta crolla
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Re: MRP Flywheel Bolt Options

Postby totta crolla » Wed May 06, 2020 11:49 pm

Surely MRP can supply the correct bolts for you?

yabaiani
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Re: MRP Flywheel Bolt Options

Postby yabaiani » Thu May 07, 2020 5:42 am

Barry said grind them down or use a lathe. My shop doesn’t want to do that...

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oldeskewltoy
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Re: MRP Flywheel Bolt Options

Postby oldeskewltoy » Thu May 07, 2020 7:54 am

yabaiani wrote:Barry said grind them down or use a lathe. My shop doesn’t want to do that...

you could call ARP and ask them........
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jondee86
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Re: MRP Flywheel Bolt Options

Postby jondee86 » Thu May 07, 2020 1:49 pm

If ARP can't help you out with a shorter flywheel bolt, then grinding will get the job
done. The maximum stress in the bolt is in the shank and top of the thread, so taking
3mm off the end is not an issue. The main thing when grinding is to have a container
of water beside the grinder, grind in short bursts (just a few seconds) and cool the
bolt between bursts by dipping the end in the water.

What you need to avoid is getting the end of the bolt hot enough to affect the heat
treatment of the threads. So you don't want to see red hot metal or "blueing" on the
end of the bolt while grinding. This is the same technique used on wood working chisels
and other hardened steel tools since Noah built the Ark. Just go at it slowly, keep the
bolt cool and it will solve the problem if you can't buy shorter bolts.

Cheers... jondee86
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allencr
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Re: MRP Flywheel Bolt Options

Postby allencr » Sat May 16, 2020 11:40 pm

Are you talking about shorter - length -, or a shorter shoulder, that un-threaded portion under the bolts head that is a close tolerance fit into the flywheel? Too long will bottom out & not clamp, its gotta be right!
Automatic flex-plates must have a shorter bolt.
A hacksaw should take care of the length. Do a nice job cleaning up the end & first thread,