Port and Polish

[timp224]

I was just wondering what i could do myself to help my engine with air flow. I just bored my ex out to a 416 and im in the process of putting it back together. Wanted to do what i could before i got the engine back together.

[Thumpin440ex]

P&P always helps. Looking into a stg 1 2 3 hot cam. They help to, depending on your riding style..

John

[slightlybent47]

Porting is good and it can be done too many degrees. You can do a light port or a full race port or anywhere in between.
Having said that let me tell you this, porting is easy to do, BUT it can be done wrong and do more harm then good. I would take it to someone that has experience or find a head that you can use as a guide if you want to do it yourself.
Porting is not very expensive so consider a pro.

[timp224]

What can i do myself, i have it bored to a 416 weisco 11-1 piston, stage 2 hot cam, hd cam chain, fst second oil cooler, 450r carb jetted full exhaust, k&n filter, i have heard that the welds could be cleaned up? I have the head apart still.....

it help more if u put a carb on it bc ur stock carb made of stock topend......

[timp224]

i did a 450r carb

[jensenracing77]

don't wast your time doing it yourself. you will almost certainly be worse off than not doing it. even if you try to copy one that was done by a professional it is likely to not work good. the top head porters most of the time are porting them to work in conjunction with there cam as a package and the drop in cams are mostly made for a stock port configuration. most likely you won't ever notice any gain with a home port job but very well could notice a bad home port job.

boy i know this will shake the hornets nest. not trying to do it but just want you to hear the truth.

[bherriman]

Originally posted by jensenracing77
don't wast your time doing it yourself. you will almost certainly be worse off than not doing it. even if you try to copy one that was done by a professional it is likely to not work good. the top head porters most of the time are porting them to work in conjunction with there cam as a package and the drop in cams are mostly made for a stock port configuration. most likely you won't ever notice any gain with a home port job but very well could notice a bad home port job.

boy i know this will shake the hornets nest. not trying to do it but just want you to hear the truth.


He is correct, and 90% of the time someone trying to do their own port job will just hog out the ports as large as they can (which actually is worse than stock porting) instead of keeping a straight and smooth transition from the intake boot to the intake "runner". In my opinion on the 400ex the exhaust side benefits more from a good polishing and slight port than the intake anyways.

[jensenracing77]

Originally posted by bherriman
He is correct, and 90% of the time someone trying to do their own port job will just hog out the ports as large as they can (which actually is worse than stock porting) instead of keeping a straight and smooth transition from the intake boot to the intake "runner". In my opinion on the 400ex the exhaust side benefits more from a good polishing and slight port than the intake anyways.
and if you screw up the exhaust side you won't notice as bad as if you screw up the intake side.
i have seen heads done by well named shops and well named exhaust companies that do porting and screwed them up very bad. it takes a true professional to do it right and then it is very expensive.

[Thumpin440ex]

Originally posted by 82corolla
it help more if u put a carb on it bc ur stock carb made of stock topend......

Can you say this again in english please??

There is more to porting then alot of people think. You just don't go in and open them up as big as they can go. There are tricks to it.. You want the air to go into the cylinder with good velocity, not just tumble around..

John