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Author Topic:   Valve size?
LUBEGUY07
Member
posted October 15, 2003 09:28 PM
Does 2.02 and 1.60 valves flow better the 1.94 and 1.5 size. Thease heads would be either 441 or 487 heads with a 2 barrel carb and stock intake and stock exhaust. Cam lift would be around .480 with everthing easle stock parts.


sdhnc29
Member
posted October 16, 2003 08:34 AM
Yes 99.9% of the time , if done correctly , this will improve air flow .

Steve

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


LUBEGUY07
Member
posted October 17, 2003 05:24 PM
OK THANKS STEVE does doing it right mean opening the rest of the port or bowl hogging?


unlucky13
Member
posted October 19, 2003 05:14 AM
LUBEGUY07 ,

Yes on opening up the pocket under the valve , NO on the bowl hog . If you can hand grind this area then your set . If you can't , then make sure that the machine shop you use has a Serdi , a Newen , or another seat and guide machine that uses pre-formed cutters . The exhaust will require a 30deg. top cut , 45deg. seat , and a 75-80 degree radius down into the bowl . The intake need's a 30deg. top , 45deg. seat , then a 60deg. followed by a 70deg. This combo has produced the best results in most stock heads that don't allow hand blending the bowl area . If a bowl hog is used , you can actually lose air flow .

unlucky13,
I have never actually run into a situation where less air flow created more power , so yes this would be a needed change in any compression ratio engine . As for HP gain , I have never actually done a back to back test due to what I just mentioned .

Steve

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Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


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