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before clicking on anything else....look to the bottom left of the webpage you're looking at right now. you'll see a list of similar topics that have already been posted. almost all of them look like information you're looking for. "head porting" "porting/die grinder", "porting/polishing", and "porting polishing heads". those threads will be time well spent for you.

 

i wouldn't expect much. a better question might be what are you trying to do? there are some minor improvements to be made. but this isnt' the ticket to making the EA82 a race car either. it's not a huge power plant and if you're looking for horsepower, i think you'll be disappointed. are you talking about a turbo or non-turbo engine? i wouldn't tear apart a perfectly good EA82 or ER27 (same motor - 2 more cylinders) just to port the heads. if you're already taking it apart for some other reason then i would (and have) do it. but the gain is so small and these motors are not power houses, it's probably not worth it unless you're really just interested in trying it out and doing the work (like kevin). but most are loooking for fast cars and you're not going to get that by porting an EA82.

 

basically you don't want to enlarge or redesign the heads, unless you're looking to have them flow tested, matched and get crazy...i'm assuming you're not. in that case you're looking to just smooth out the passages and match the manifold, gasket and head all together. there is an excellent website detailing the process.

 

i had a set ported on an 86 XT EA82, it ran well afterwards but it wasn't my vehicle and it didn't run that well before hand so i can't comment on before/after results. i posted pictures on http://www.xt6.net. i can't really say it was noticeably faster than any other XT i've riden in. felt nice and maybe a bit of gain, but nothing drastic. that's alot of work for "i think i felt a difference?". that car had to come apart for a headgasket leak anyway. those heads were done by an aluminum head specialist, not me.

 

i posted pics of the ER27 ports and gaskets and intake manifold, and porting that i did. same basic design as the EA82. the intake, gaskets and head openings don't line up all that well and the gaskets protrude into the airflow a good amount. for improved flow, based on what i've seen in the ER27, an area to focus on is cutting the gasket to match the head and intake. i smoothed out the head ports, then matched the gaskets, then matched the intake to this. i have pictures of how much the gaskets protrude into the air flow at xt6.net. i'd think that's more significant than the heads themselves.

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I have ported heads on ea81 and ea82's.Never done the mpfi heads and intake on a ea82,but on the single port ea81& ea82 I have gone up to 1.5" on the intake and it has helped alot in the upper rpm band.As others have said "bigger is not always better". One thing I have noticed when head porting is that when you do start out, think about what rpm band you want your engine to make most of its power.Like if you are building a trail rig you don't want to do very much except polish up the combustion chamber and maybe a light polish on the exhaust.

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Also, on SPFI/Carb intakes, think about that long tube of a manifold the air/fuel has to go through to get to the heads. Ouch. There's a maximum flow killer right there. You could get it opened up with an extrude-hone type process ($$), or attempt to cut it open, port it, and weld it back up ($$, time, weldin skillz).

I would think the MPFI setups will show more gain from some port work (when combined with manifold work) then the SPFI/Carb setups. Also, remember that these engines are already putting out a fairly decent hp/L number. A 5.0 Mustang V8 of the same era (mid 80's) as the EA-82 puts out less hp/L. Those engines respond pretty well to port work, but the EA series already has fairly good flow.

EA-82 SPFI: about 50 hp/L

Ford 5.0 HO V8 (1987): about 45 hp/L

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