Actual 998 Chat about rebuilds

General Chat with an emphasis on BMC Minis & Other iconic cars of the 1960's. Includes information on MK1 Action days.
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Peter Laidler
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Re: Actual 998 Chat about rebuilds

Post by Peter Laidler »

Yes, Duplex...... peace of mind I say
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Costafortune
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Re: Actual 998 Chat about rebuilds

Post by Costafortune »

Duplex chains are heavier and require more effort to rotate.

A good simplex chain is perfectly fine.
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mk1
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Re: Actual 998 Chat about rebuilds

Post by mk1 »

I believe that Swifty uses simplex chains on all his engines nowadays.
Richspec
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Re: Actual 998 Chat about rebuilds

Post by Richspec »

mk1 wrote: Tue Jan 17, 2023 3:53 pm I believe that Swifty uses simplex chains on all his engines nowadays.
if i was building a race engine I'd go highest quality single i could find, rotational losses and all that...
But for everyday longevity and not chasing every HP i use duplex as default.
Wanna see what I'm playing with? Youtube Channel
Caution ;) may contain 8 Ports, Xe's and VTec's, I don't do standard!
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snoopy64
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Re: Actual 998 Chat about rebuilds

Post by snoopy64 »

Hi,

thanks for all the supplies, I'm not looking to vastly improve anything, just a std set up with std rockers...
Cheers

Kevin
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Costafortune
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Re: Actual 998 Chat about rebuilds

Post by Costafortune »

Simplex JWIS chain. Has an A Series timing chain ever snapped? I've seen them so shagged they've worn through the timing cover, but never broken.
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snoopy64
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Re: Actual 998 Chat about rebuilds

Post by snoopy64 »

Vernier gear worth it?
Cheers

Kevin
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timmy201
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Re: Actual 998 Chat about rebuilds

Post by timmy201 »

I prefer using an offset woodruff key. The vernier adds an extra level of complexity that can come loose

There’s also the type with extra key ways on the crank sprocket to dial it in
https://outlawspeed.com.au/shop/cs8000
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Costafortune
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Re: Actual 998 Chat about rebuilds

Post by Costafortune »

It's absolutely worth timing the camshaft in properly as well as having a good distributor built with a correct advance curve. You can lose 10 bhp with ease if they aren't right.

That and bumping up the compression ratio to 9.75:1 to run on super unleaded will really give it some sparkle. A good standard 998 Cooper was only a couple seconds slower to 80 mph than a 1071 S.
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snoopy64
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Re: Actual 998 Chat about rebuilds

Post by snoopy64 »

mk1 wrote: Tue Jan 17, 2023 2:40 pm Another vote for the evo 1 or alternatively Calvers CST229 is a good bet too.

Personally I put duplex's on all my engines, not sure whether it's really necessary though.
997 type cam isn’t quite the same as the 998 so will the dizzy need re curving?

Please excuse my ignorance!
Cheers

Kevin
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