Larger Valves??'s for 317 and 243 heads
05-09-2007, 10:02 AM
#1
Larger Valves??'s for 317 and 243 heads
So when can you justify putting in larger valves? Is this only after heavy port work? Really large cam shafts with big bores? I'm talking about putting in larger than stock intake and exhaust valavs in a stock head, with little port and polish work?
This would all be with the stock truck intake.
Better yet, what if I was to upgrade to the Vic Jr. intake
This would all be with the stock truck intake.
Better yet, what if I was to upgrade to the Vic Jr. intake
05-09-2007, 11:39 AM
#3
Installing larger then stock valve for the meare sake of doing so could be potentially bad, power-wise and mechanically. One of the reasons for larger valves is due to increased bore diameter, without knowing what you are building we can only guess you are building a 4.8L or a 500CID monster. Also with minor port work, it can be benificial, but you need to disclose the cam specs, engine specs and what you plan to do with the engine ... to thoughtfully answer your question.
05-09-2007, 12:21 PM
#4
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Originally Posted by 12secSS
Installing larger then stock valve for the meare sake of doing so could be potentially bad, power-wise and mechanically. One of the reasons for larger valves is due to increased bore diameter, without knowing what you are building we can only guess you are building a 4.8L or a 500CID monster. Also with minor port work, it can be benificial, but you need to disclose the cam specs, engine specs and what you plan to do with the engine ... to thoughtfully answer your question.
05-09-2007, 01:01 PM
#5
Ok, what size valves are we looking at? 
I think 2.02/1.60 would work well with that setup. Now if you plan on the Victor Intake, will you be trying to utilize the power band of the intake? If so, you will need to up the size to about 2.08/1.65 or so. The converter may be a tad small, but can work with the setup. Good luck!
I think 2.02/1.60 would work well with that setup. Now if you plan on the Victor Intake, will you be trying to utilize the power band of the intake? If so, you will need to up the size to about 2.08/1.65 or so. The converter may be a tad small, but can work with the setup. Good luck!
05-09-2007, 01:05 PM
#6
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Yeah the gentleman porting my heads said if I wanted to get upgraded valves to get what you had mentioned -2.02/1.60...I just didn't know if the cost would be worth it in the end since I suppose compared to a lot of setups mine wasn't too wild and I was using the stock truck intake for a long time.
so basically it would be worth it to get the valves?
Thanks for the info.
so basically it would be worth it to get the valves?
Thanks for the info.
Last edited by KB; 05-09-2007 at 04:00 PM.
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