Shortened valve guides

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gazman
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What model do you have?: rsk 718
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Shortened valve guides

Post by gazman »

Hi guys

I am busy rebuilding a rsk718 with a slightly modded 1600 sp motor with dual carbs.I am fitting new valve guides and want to know if i will get better flow on the heads if i shorten the guides.

Thanx

Charl
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Ron&Gill
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Re: Shortened valve guides

Post by Ron&Gill »

HELLO Charl!!! Kom jy braai Saterdag??

Voor jy te heavy in gaan op die technicals in... gaan gou na die Introduction thread toe, en gooi n storie daar. Die ouens kan nogals ... um... punteneerig raak daar oor... o, en sonder pictures glo ons jou nie... :lol:
1964 T34 - The Razor: viewtopic.php?f=23&t=10290
1956 T2 1b - Gill's bus: viewtopic.php?f=23&t=10948
1967 T316 - viewtopic.php?f=23&t=10931 & viewtopic.php?f=23&t=15977
2000 beach buggy - viewtopic.php?f=23&t=10915
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Ron&Gill
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Re: Shortened valve guides

Post by Ron&Gill »

To answer your question: No. The relative area presented resisting the flow of a valve guide compared to a valve stem is negligible, especially since it is at an angle and in a volume much bigger than the choke point, which is most certainly in the valve gap opening iself, if not in the manifold (unlikely). The risk of valve stem failure is much higher. I am of the opinion that you will not be improving the engine by shortening the guides.
1964 T34 - The Razor: viewtopic.php?f=23&t=10290
1956 T2 1b - Gill's bus: viewtopic.php?f=23&t=10948
1967 T316 - viewtopic.php?f=23&t=10931 & viewtopic.php?f=23&t=15977
2000 beach buggy - viewtopic.php?f=23&t=10915
calooker
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Re: Shortened valve guides

Post by calooker »

Don't do it.
For what it's worth, ignorance has no limits ......
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Re: Shortened valve guides

Post by IMPI »

And that is why they call it shortening it shortens the life of the engine :lol:
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gazman
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What model do you have?: rsk 718
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Re: Shortened valve guides

Post by gazman »

Hi Ron
Will pop around for a beer after work on Saturday , have the inlaws over for the weekend so will have to braai at my own house!
The panelbeater promised me the car back at end of June , will post some pictures as soon she has some paint on her cheecks.Going for the Eleanor look , the Mustang in" gone in Sixty seconds."
Cheers all and thanx for the help.(Calooker i like the yellow porsche)
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