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Old 12-20-2011, 05:44 PM
Steve C. Steve C. is offline
Ultimate Warrior
 
Join Date: Dec 1999
Location: Liberty Hill, Tx. (Austin)
Posts: 10,927
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"....a little bigger?"

As a general rule when going from a hyd flat tappet to a solid flat tappet many add a significant amount of additional duration. Not uncommon to read 8-10 additional degrees, while in many instances its touted more than that.

Example, note the combination here:
http://www.pontiacstreetperformance....uild45500.html

After this write up Lee improved on his time over what is stated here. I believe it was a best of 11.46 at 115.4 mph. And in our horrid Texas summer heat he ran 11.70 at 113.4 mph. Lee later changed to a Ultradyne solid flat tappet cam with 247/247 degrees at .050 with .575 lift on a 108 lobe separation. With the change he ran a best of 11.27 at 119.61 mph. And Lee reported no significant decrease in driveability with the change dispite the 16 degrees additional intake duration.




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__________________
'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 )
Old information here:
http://www.hotrod.com/articles/0712p...tiac-trans-am/

Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine)
Best time 5.13 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension
https://www.youtube.com/watch?v=qDoJnIP3HgE