Heavy valve springs

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montuckymatt
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Heavy valve springs

#1

Post by montuckymatt »

I have acquired a set of leinweber 420 regrinds. Can anyone steer me in the right direction on a source for heavier valve springs? I am assuming I will have to replace the stock springs if I use these cams. Anyone else running these?
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Re: Heavy valve springs

#2

Post by RooDog »

Perhaps you could just simply ask Honest Leinwweber him self for spring recommendations....

https://leinewebercams.com/contact_us.php
montuckymatt
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Re: Heavy valve springs

#3

Post by montuckymatt »

RooDog wrote: Mon Jun 06, 2022 7:51 pm Perhaps you could just simply ask Honest Leinwweber him self for spring recommendations....

https://leinewebercams.com/contact_us.php
I sense I'm missing something here....please PM me if that is the case.
Thanks!
panhead
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Re: Heavy valve springs

#4

Post by panhead »

I assume RD means that Leineweber has a solution. They sell high performance valve train components, here is information: https://leinewebercams.com/PG7_HPVALVE% ... 202016.pdf
montuckymatt
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Re: Heavy valve springs

#5

Post by montuckymatt »

Here is the info on my regrinds for those who are interested
Screenshot_20220607-200311_Hancom Office S Viewer.jpg
Screenshot_20220607-200311_Hancom Office S Viewer.jpg (46.85 KiB) Viewed 468 times
I emailed with Justin at Leinweber and he said using stronger springs is not needed. He did recommend shimming if I'm going to he racing around alot.
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Re: Heavy valve springs

#6

Post by svkiwi »

possibly email your mate Jason again and ask him for his recommended seat pressure. Once you know that, you can determine the closed spring length to achieve that pressure. A simple way to check that is setting regular bathroom scales up on a drill press. Sit the spring on the scales, zero the scales reading, then, using the drill press [not switched on!!] compress the spring , observing the reading on the scales until you've got the recommended pressure. Note the length of the spring. That is the length you'll need to shim to. Then, you can assemble valve assembly to barrel, fit barrel, set tappet clearance, THEN check for coil bind at maximum lift. Could be you will indeed need heavier springs! But I feel his initial response to you was far too vague....
montuckymatt
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Re: Heavy valve springs

#7

Post by montuckymatt »

I've been very happy dealing with leinweber cams so far. Any questions I have had have been answered. The cams look beautiful and Justin has answered all my questions to date. They offer a couple of regrinds and different lobes for flatties if anyone is looking. Would recommend them to anyone.
chuckthebeatertruck
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Re: Heavy valve springs

#8

Post by chuckthebeatertruck »

To add a data point, I have very similar cams in my big twin flatty. There was zero issue with stock springs, though they did get close to bind. I choose to have mine treated with dry lubricant to help with the heat.

I don’t have enough miles on it yet to draw conclusions.

But, you’ll like those cams.

Mine are lumpy at idle, but pull very well.
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