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Old 08-16-2019, 11:32 AM   #28
Tim Ayers
Senior Member
 
Join Date: May 2010
Location: NJ
Posts: 2,937
Default Re: FH Valve Springs

Quote:
Originally Posted by Bored&Stroked View Post
Here is some data on spring pressures - that I compiled via my own tests . . . will give you some ideas on options:

Flathead Spring Pressures
Author: Dale Hays, Vintage Horsepower, daleohays@gmail.com
Date: 08/14/2019

The following was done with a hydraulic spring tester have used it for quite a few years and it is quite accurate (until you get below about 50 PSI).

1. Isky 185G Single Spring (new)

110# @ 1.900
100# @ 1.950
85# @ 2.00

2. Isky 185G- Single Spring (used)

180# @ 1.605
82# @ 2.00
50# @ 2.125

3. Iaky Dual Valve Springs (I don't use them on anything)

80# @ 1.765
180# @ 1.390

4. Ford 49-53 0BA-6513 (from Mac VanPelt)

60# @ 2.00
45# @ 2.125

5. Lincoln Zephyr 86H-6513 (from Mac VanPelt)

82# @ 2.00
55# @ 2.125

So - if I was going to put say a .375 Potvin 3/8 cam in a street engine, I think I'd use the LZ springs from Mac and I'd install them at 2.0625 . . . should give me about 65 lbs on the seat. So there yah have it . . . . one more opinion to add to the mess! LOL

Interesting how the stock v. LZ @ 2.125" is a 10 lb difference, yet at 2.00", the difference is 22 lbs.
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