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Discussion Starter · #1 ·
I am Considering a 95 or 98 build with a 37G cam. I have a set of take off heads with 8 miles on them and I am considering headwork on these.

Does it enhance performance to have larger valves installed on these heads (for the 37G build), or just to stay with stock sized valves?


In regards to a 95 build, I also have jugs with 8 miles on them also. Since they are not seasoned, am I better off buying 95 jugs?
 

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IMO, keep the stock valve sizes. Do a street port job and bore your 8 mile cylinders.
 

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Discussion Starter · #3 ·
Springer, thanks for the response. I know in 05 they went to smaller sportster type valves, will this be a problem? Does the smaller stem lead to oil consumption? I know that the old style valve seal is a part of the problem, but is the stem size itself part of it? Thanks
 

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Actually the smaller stem valves equate to a larger port, because there is less stem inside the port. The guides are shorter also, increasing the area again (all good). Not to mention the valves are lighter and have valve springs that are less prone to harmonics (more good).

Valve seal issues seem to have been addressed.
 

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Discussion Starter · #5 ·
That was a great explanation, thank you for your response. I would think that the 06 heads use the same smaller valves, but the 06 happen to flow better through design?
 

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Stock for Stock the '06 heads flow better. Ported for ported I feel the '05 heads are better. The '05 heads have an advantage of starting off with smaller exhaust ports and therefor can be ported to what I would consider a better port design. The '06 heads already have too big of an exhaust port and no matter how much you cut away they just don't get smaller. :D
 
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