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Ea81 and Ea82 head porting.
Posted 14 December 2005 - 09:15 AM
Posted 14 December 2005 - 12:03 PM
I guess I can't really help, since I have no experience in the matter. But... I would grind it down.
Hmmm... someone with a flow bench and spare parts (and spare time) should test out the best porting method for our heads.
Posted 14 December 2005 - 12:08 PM
Are you talking about the cast line in the intake area that runs with the flow?
Yes that is the one that I am refering to.I guess I should be a little more specific.
Posted 14 December 2005 - 03:32 PM
Just remember - when it comes to porting, bigger is definitely not always better!
Posted 14 December 2005 - 06:53 PM
Unless you are turning insane RPMs, I would remove only small amounts of material in areas that protrude into the direct flow. I grinded down the areas under the intake mounting holes. I took a course sanding wheel to just knock off the casting flash and give a smooth transition. I also matched the intake and gaskets also. The key factor to remember is that VELOCITY makes power. That mixture needs to blast into the chamber with some serious motion. Too large of port will only slow this down. Your cam needs to match your ports, you will throw away power if they don't match. I'm running stage 3 cams and I'm still on the conservative side with my porting. Seen too many people open ports up wide only to find out that their engine doesn't do crap until the RPM comes up; by then the race is already over.
Usually. people do more harm than good when porting heads. A good 3 angle valve job can give you excellent results with a stock port.
Rule of thumb- remove material only in the narrow areas, and only remove a small ammount if you have no flow measuring equipment.
Posted 08 December 2014 - 09:05 PM
I've been searching but unable to find pictures of port jobs before and after.
It must be a well guarded secret.
Any one got a pictoral?
Its not hard just time consuming. Anyone wiling to share their mistakes????
Posted 09 December 2014 - 09:02 AM
Posted 27 December 2014 - 06:06 PM
Look up Pocket porting namely the area just before the valve seat that is where you pay the most attention as it will give about 80 percent of the benefits power wise, with such a long and not very efficient intake runner actually opening up the throat of the port will likely be of academic benefit unless like some of the Airplane or Gyro people you make a totally new intake manifold and run twin carbs above the heads.
As for flow benches they can trap people very easily as you can port to get better numbers and lose real power because of poor mixture mixing and fuel dropping out of suspension, The real standard these days is what is known as a "Wet" flow bench look it up and see what I mean, An older dry flow bench is only as good as the person using it who has decades of real world knowledge.
Posted 28 December 2014 - 01:58 PM
My former ride had ported heads that i had a local shop do for me. If i remember right he did not remove too much material. HIs goal was to smooth any transition area such as under the valves and any corner and smooth the walls everywhere. He also did a 5 angle valve job and shaved .030 off each head to up the compression. That motor moved out pretty well for itself even without a aftermarket cam grind. I did however have a tuned weber for that combo as well as a true 2" exhaust the whole way back.
As for that rib i think he removed most of it if not all of it.
Edited by hatchsub, 28 December 2014 - 02:01 PM.
Posted 29 December 2014 - 06:05 PM
Posted 30 December 2014 - 03:11 PM
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