Effectivity of light port work?

[dv/dt]

So when i threw my scoot together i didnt port a single thing. Just tossed everything together and it ran great. BUT i can't help but think "is there more?" when i see pics of a lot of members here opening up the intake port windows behind the reed block. Or taking material out of the block to help match the transfers.

Is there much to be gained with this work? 10%? 20%?

I live in the snowbelt so when the snow falls its time to take things apart and improve them for the next season!

[veedubh20]

everyone has differ porting style.

if you take take time on porting willl make big different, on clean works!!!

[geezer101]

What finish should I be aiming for in regards to working on the case inlet ports? My SE50 looks like it'll be a long term project so while I've got it in pieces I had a go at tidying them up (not finished yet)-

Is polishing really that detrimental to the air/fuel charge or does that only apply to the inside the crank case? I've die ground then file finished the walls and sanded them smooth, then polished them and finally dressed the inlet floor and port walls with a knurling ball. Sorry about the huge pics, no idea how to reduce the sizes

[evilone]

Sorry about the huge pics, no idea how to reduce the sizes

Do you have Microsoft Office?
A quick easy way to crop/resize/etc is go to Microsoft Office Tools and then go to Microsoft Office Picture Manager. 480 x 640 is a good size.

[evilone]

Is polishing really that detrimental to the air/fuel charge or does that only apply to the inside the crank case?

Polishing causes fuel mixture to stick to the surface like mist on your bathroom mirror. You want the mixture to stay mixed and make its way to the combustion chamber.

[kauaianman]

Is polishing really that detrimental to the air/fuel charge or does that only apply to the inside the crank case?

Polishing causes fuel mixture to stick to the surface like mist on your bathroom mirror. You want the mixture to stay mixed and make its way to the combustion chamber.

so polishing intake, transfer, and boost port a bad thing?

what about intake manifold?

[fastplastic]

smooth is bad just rough it up a bit

[swimmingfree]

here some info for you
1 dont remove the support in the middle
2 a 0.5 hole has the area of 0.1963 a 0.75 hole has the area of 0.44173 but remember this is only 1/2 of the deal exgas out is the other!!!

will it help yes but cant tell you how munch... no !!!
do a compression test the se50 number are 114 to 171 ( in the book at 3-8 ) and the compression ratio is 6.6:1 ( in the book at 1-3 ) .... so milling the head is something to think about as well..
swimmingfree

[Bear45-70]

Minor porting is not gonna do much of anything but make you able to brag about it. Even major porting is really only to help the top end, and not much at that and is not gonna help street ability at all. Major porting without improving the intake and exhaust is a waste of time. So for the stockers or slightly larger engines, it will make you feel good but don't expect a 10% increase in power. Polishing is something they did back before they knew better.

[bakaracer]

if your going to polish, only do the exhaust port,head and piston top so its harder for carbon to stick.

[kingkamehameha]

I wouldnt waste time on porting the se50 block. It takes practice and alot of patience to port the intake and boost port. My elite motor in my spree was the second motor i ported and there was lots of room for improvement. I did two more since then and the last one i did was clean as a whislte. It took me 4 port jobs to get my skills dialed in. Like i said the first few times arent gonna be the best. Just go slow and ask lots of questions before you start removing material.
You have to take the lips on the sidewalls back so that the walls go straigt back. Use a ruler or straight edge as a guide. Any divets or dips in the walls will cause turbulance. You can knife edge the bridge support and there is also a little triangular section in the transfers that can be opened up. Things need to be SMOOTH with no imperfections. Take the time to go back over everything with sand paper or a sanding bit on the dremel. I use a nice 220 but as long as you dont polish anything like baka and bear mentioned.
On a stock set up porting isnt needed. When your doing the whole shabang with the bore kit and crap then correct porting makes jetting alot easier. The motor runs more efficiently

[kingkamehameha]

And by the way take a good look at my rushed port job in my spree build page. Thats a good example of a half * job that should have been alot cleaner