I started porting today. i go one iron cut. This is a N/A s4 with s4 turbo rotors, 3mm seals, ect, ect. hx35/40, 1680 primary and secondarys, cumstom exhaust mani. s5 turbo INtake manis

Arron Cakes advice that i took-- Move the exhaust ports down about 3MM and widen them 2MM. Leave the primary ports alone but smooth all the transitions. Move the secondary out toward the rotor housing 2MM then extend it down to smooth the transition. Move the aux port out to the rotor housing 2MM and then extend it about 2MM up and in towards the iron at the top edge.

That gives you the basic port shape. Now smooth all the port bowls and the transition from the runner to the ports.

Based on these pictures how did i do? SHould i change anything, edges? SHould i have brought the tear drop down more? Feel free to tell me anything and everything on your mind about it! i still have some smoothing out to do.
STOCK
PORTED

 

looks alright - better than some of the local crap i've seen. :-)

 

Well what should i have done to make it better than "alright".

 

Looks like you have a basic set of tools to start with but I wouldn't recommend using that iron after the practice job. Also, yank the rear stationary gear out next time.

B

 

If im suppoed to take the exhaust down 3mm am i suppose to also take the sleeve down? i didn't think the sleeves were that thick. right ow the port and sleeve are flush at the bottom but at the top the iron housing has about 3-4mm till it would be flush with the sleeve. Also I noticed my all my spark plug holes have hair line cracks coming from them there about ..... < that long

 

Why would you not use it? whats wrong with it? what do you mean by basic set of tools? Im trying to get better at this not just read these kind of comments. can i get some imput on the comments..

 

well, i realize that these are just photos, so don't take this the wrong way. following Aaron's advice is usually a good thing, but porting an engine based solely on someone's instruction may not be very prudent. did you use a template in addition to Aaron's guidelines?

you may want to confirm the interaction/relationship between the port and hard seals (apex, corner and side) on the rotor.

 

The opening edge on the standard port is way too close to the water jacket's square ring land. Also, my understanding on the 5th and 6th ports is that it's not beneficial to grind them out and make them humongous for a number of reasons.

The basic set of tools - it was a compliment meaning that you've got a starting point that's well past most others. It looks like you've got a set of basic tools to work with already.

B

 

Bingo on both counts.

B

 

I have my (very strong) opinions on exhaust ports but I'm sure the rest of the forum doesn't want to hear most of them. I'll give you one, though - Don't widen it and whatever you do don't go crazy on it.

B

 

[QUOTE=BDC;9304024]I have my (very strong) opinions on exhaust ports but I'm sure the rest of the forum doesn't want to hear most of them. I'll give you one, though - Don't widen it and whatever you do don't go crazy on it.

OK, well let me ask you this. how would you even port down when the sleeve is flush with the housing? I think of it this way, It don't matter how big the "enter" hole is. if the exit hole is still the same orignal size there isn't going to be any more air flowing threw than before. I can actually understand why you wouldn't want to go crazy but why wouldn't u want to widen it. I haven't even started on the exhaust ports yet.

 

Yes i made a template. I made it out of plexi glass. It took me roughly 3 hours to make the template. it was precise but when i was grinding one of the stone pieces shipped off and hit the edge of the iron and plexi glass so i had to go eeven bigger b/c it messed the edge up on the iron. The intersection between the port and seals is what i really want to know. should i slant them like judge ito templates (i think thats who's they are). should i just sand them smooth with a little round to them....

 

I pm'ed arron about this exact thing and he no answer so i said times up time to learn myself. I undestood myself your not suppose to make the 5th 6th ports any bigger because you loose low end and couple other things but im not to worried bout low end myself

 

looks GOOD!

it does not look like u have opened it up to big, it
looks all of your seals will stay in place

as far as radi the closing of the intake ports, i would do it per ito's instrutions


my opinion on the exhaust port very's
??? n/a
??? turbo
????nitrous

lets see where yourgoing w/ this?

 

You don't widen them because of theoretical apex seal issues -- the wider the port, the more tendency a hot seal will want to banana itself out.

Besides, people got the wrong idea on exhaust porting. Just look at the length of the exhaust stroke and ask yourself, "is there any real benefit to making this thing the size of a watermelon?"

B

 

You don't widen them because of theoretical apex seal issues -- the wider the port, the more tendency a hot seal will want to banana itself out.

Besides, people got the wrong idea on exhaust porting. Just look at the duration of the exhaust stroke and ask yourself, "is there any real benefit to making this thing the size of a watermelon?"

B

 

That seems very possible

[QUOTE=Besides, people got the wrong idea on exhaust porting. Just look at the duration of the exhaust stroke and ask yourself, "is there any real benefit to making this thing the size of a watermelon?"[/QUOTE]

Well i just figured if made the intake bigger to bring more air in the exhaust should get bigger also. but i guess the way the exhaust stroke is would it even matter.

 

That's working off of the assumption that the intake volume and exhaust volume are identical per complete stroke. They ain't by a longshot.

B

 

correct

 

For a first porting job, it doesn't look that bad. I'm going to be honest and say that when I first ported a set of irons, well... I'll just say you did better.

You need to check and make sure that nothing is going to catch with the side seals. And those ports still look a little rigid. A better idea would have been to port them with a local builder watching over you.

+1 on not recommending using that already ported iron. Maybe try find some local already junk motors to pull apart and practice porting.

You said you cut a port out of plexiglass? As in you made your own port?