frostie

I think you will benefit greatly. Your port looks good, I think I would use the cartrige rolls a bit more in the bowl to smooth them out. For the most part Im sure you will see major benefits from what you did.
I spent, Im guessing, 15 hours on my head alone.
I bought a brand new ATS manifold, I probably spent 3 hours porting and polishing it. The manifold is a good improvement, but needs some work right were the exhaust enters the manifold out of the head.
Its all good, Im sure you will enjoy the benefits

mopar2ya

It does take alot of time. I have about 30 hours in this head for a guy in Texas and about 8 in the ATS manifold, but its coated inside and outside as well. I really want some feed back. Has anyone flowed the head stock and ported yet?

bigragu

Always have been curious about the porting thing, but school me here on my thoughts: Doesn't the removal of metal thicknesses, especially in areas of extreme heat and possibilities of expansion and contraction, tend to make the structural integrities weak? Being a sheet metal worker and dealing with metals of all sorts and guage thicknesses, I tend to wonder about the long term effects of porting, which to me is "thinning out"?? Please advise. Carmyne

goodtyms

I didn't remove (much) metal in areas that were close to water jackets or other areas where wall thickness might be an issue, at least in the head. Instead, I carefully blended so that there was a smooth, undisturbed flow of air, maintaining the intake swirl as designed by Cummins.

I did remove more metal in the OEM exhaust manifold, but there's no risk of water jacket leaks like the head, and I have a spare if it cracks. Besides, by then, I may be convinced to upgrade to an aftermarket manifold, but I'm almost always willing to try the lower buch mods, especially after seeing the restrictions in the OEM manifold. So far, so good - lower egts and no leaks.

mopar2ya

You would want to be a bit more carful in the exhaust. But its more important as to where you take it out as to how much. I can make a smaller port out flow a larger port just because of the shape. It takes alot of time on a flow bench (we have one inhouse) to find what works well. Keep in mind different driving/power needs require different porting. CFM is just one aspect of it velocity is another, especially when you look for fast spool vs peak power.

I have a stock head and a ported one I hope to flow this weekend and will post #s. On the intake 80 grit is fine, but the exhaust you want smooth and shiny like you did.