| [ Total Views: 1007 | Total Replies: 2 | Thread Id: 757 ] |
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 70AutoStik
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| posted on September 23rd, 2002 at 01:53 AM |
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If you have a seriously large cam, ratio rockers are unlikely to add any real improvement (and will probably cause the valves to hit the cylinders - I
assume you are running a suitably high CR.) The acceleration in the valves they will produce will severely shorten the life of your engine. If you
are running a strictly strip car and have buckets of cash (and little sense,) you will need at least titanium valves (about $300 each,) triple springs
with titanium retainers (about twice that) and some serious pushrods (about the same again.)
In other words, no. Ratio rockers are a great way to increase the power of a stocker without splitting the case (except where they're specified
for a cam,) but are an expensive addition to most VW engines. If street use is not the issue, or your cam is simply not working, even with
appropriate carbs; get head work done - you'll get far more bang for your bucks.
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70AutoStik
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| posted on September 23rd, 2002 at 09:36 PM |
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With that info, you definitely need head work. Get a "Hemi - cut" while you're at it, and install spacers to bring your CR down to
about 9 (or less,) unless you're running leaded race fuel, such as C12 (the ban has just been lifted on this; but you must run a log book to
prove you are only using it for legal race meets,) or methanol. If you then adjust your mixture and timing to suit, you'll find you are making
more power.
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jakriz
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| posted on September 24th, 2002 at 07:40 PM |
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shake?
I have 298 duration & my car idles like a stocker without any shake. Check the syncronisation of your carbs?
As for the rockers, I had 30/70 pobjoy cam & I added 1.25 rockers & it made a big dfference, I've since changed the cam to a K-8 which
made much more tourqe & I now have a set of 1.4 rockers to go on for even more lift & power. What type of cam is it exactly?
Jak |
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70AutoStik
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| posted on September 24th, 2002 at 08:47 PM |
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If you have a K-8 it was designed to be used with minimum 1.4 rockers & has an adverised duration of 304. High lift cams can cause problems with
ratios however -depends how long you want your engine to live...
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jakriz
Wolfsburg Wizard
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| posted on September 25th, 2002 at 05:41 AM |
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duration
I've been using this combo for 12 months & with 500 thou lift 6 supersprint track days I still havn't had to adjust the valve
clearances. & thats revving it to 7000rpm all day? Seems to be working huh? But yes they are to be used with 1.4s & thats what will be going
on soon.
Jak
[Edited on 24-9-2002 by jakriz] |
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