my port attempt...

[brentR]

i think my exhaust ports need more taken off the insides in the corners... i assume its suppose to maintain the same wall thickness all the way around? tell me what u think so far...

 

[Matt_E]

You need to bring that size further back a bit. You need to taper the port size into the exhaust port tunnel over about 1/2 to 3/4 inch or so.
Right now it's going from big to small very quickly.

 

[Big Kahuna]

uh, what are you using as a basis for your port design, it is not just making it look good, every part that you remove has a purpose and reason...... take too much off and you mess up...........

 

[D-Roc]

he is using the freestyle sportport, its coming along, do like matt said and blend the scribed shape back to the outside of the exhaust port. Fun huh? how much difference was there with the bottom of the port sleeves? mine where a little uneven before i matched them with the template.

 

[brentR]

1\2 to 3\4 eh...that far back.... yeah its fun... i find hardest part is gettin good angle with the bit ... yea they were a tad uneven too

 

[Mouthfulloflake]

the area in red seems a bit excessive.

the yellow is where I think it should taper more, and the blue...

well the blue is....

ive been drinking.

:biggthumpup:

 

[TKM]

Porting looks great so far, but you need to keep the size, ie width and height, as far into the port passage as possible. You should end up with a smooth flowing line from your port to your flange. I like to run my fingure from the flange ( manifold face) to the port so that i can feel if there are any bumps or hollows! you should also NOT have any tapering outwards or "bell" effect as you get closer to the port.It shouod be as straight as possible. You must however have a bevel on the port itself!

Hope this helps!

Karl

 

[felix5oh]

I agree with mouth lake. You should be straight and not tapered. Also if the hole is too wide it will ware or even brake.

 

[brentR]

my second attempt... i think im ready for the other side now

 

[Matt_E]

Looks a bit uneven.

 

[brentR]

let me guess the left side more than the right?

 

[Mouthfulloflake]

maybe put an old exh gasket on there and look from the inside to get an idea of the intended symmetry there?

its looking better though.

 

[romack991]

that doesnt look like the freestyle sportport to me. Maybe it is and I'm just not seeing it right, looks more like an oval than a trapezoid. :dunno:

 

[meatball]

the older sportports had an oval I believe.

 

[romack991]

the older sportports had an oval I believe.

I have both templates. The exhaust looks more like the old style. But the sleeve skirt looks like the new freestyle.

Attached is my 61x with the original sportport. Hope that helps with comparing the taper.

 

[D-Roc]

its the newer freestyle port that is not the oval. its hard to tell when it is curved like the cylinder but if you look at the template flat it is a trapazoid.

 

[jura]

That's the LPW freestyle porting on a 701, maybe it helps.

 

[Idok]

there's more to LPW porting than just the exhaust ports...lots of work in the transfers as well