Match Porting Ideas?

[James Buchan]

Ok lets start a \"Knowledge Thread\"

What does everyone use for match porting? Tools, techniques etc...

Personally what I do is start with an air die grinder using a medium conical bit, once it has opened the entrance way to the manifold I switch to a round burr type bit and continue up the chamber. Once all the heavy removal is done I switch over to flap wheels and go from a heavy grit, 80ish up to about 220ish.
Then to finish I use my dremel with the wand attachment and buff it up nice and smooth.

So what does everyone else use? And also how far up do you try and go? I go as far as my tools will allow me to safely go.

Also being the \"safety proffesional\" I always use sealed eye protection and hearing protection - this is a must for everyone IMO - I've seen what kinda damage metal shreads can do to an eye.

[Matt]

Someone will correct me if I'm wrong but dont you want to leave some of the rough surface around? from what I understood, you want a bit of turbulence and polishing the intake manifold, you would lose this.

P.s. it is quite possible I'm way off to left field on this one.

Matt

[James Buchan]

You might be right I think its to facilitate the air/gas mixture - I've never been taught by a guru or had rough/smooth surface comparisons to prove it to myself that is why i go all smooth and sexy.

So what do others think, would a slightly rough surface be a better idea?

[jim martin]

great too get things rolling, i like that   knowledge thread, sound good.
the last time i did a home port job on my manifolds i first made a steel template that i could bolt too the manifolds,i have a electric die grinder from sears that i have hooked to a variable foot pedal for speed control.used a 1/4 inch cylindrical double cut pattern [ that means it is a 1/4\" diameter and about 1 inch long and looks like it has a knurled finish like a ratchet handle] i used this to cut the base of the manifold to the pattern shape ,then used a 1/2 \"egg shape bur and blended the manifold about 4 \" up into it .as for finnishing i took a coat hanger and used 120 grit emery cloth using the hanger i bent it into a tight u shape with the cloth trapped between it [pinched]then wrapped enough cloth too make about a 1\" wheel and put it in a drill-this works nice as the hanger is flexable and with a bit of w.d 40 it cleans well.i was told not too polish the manifold inner runners  as this may cause   a condinsation effect in the manifold causing gas dropplets to stick too it instead of keeping them atomised as well as a rough surface cause a small turbulance against the rough surface which in turn makes a buffer/boundary layer in the manifold too keep the rest of the air/fuel mixture flowing smoothly,that was explained too me years ago,but not sure how accurate it is.i have used this bent rod system fof cases and everthing as you can make the rod as long as you want as well as shape the cloth from round too a coneshape

[James Buchan]

Good idea with the rod, I'll have to try that next time!

[Hansk]

On   theoldone.com  There is loads of info and pic's on head porting.
Somewhere in there is a pic of some port work and it looks like the surface
was just cut with a bur. No polishing no nothing . There they say \"when we do our own heads, this is what they look like. The motor doesn't care how pretty it looks, only what shape the port is.\"
 So now I just leave my ports and intakes rough.  They also say there should
be about a 1/6\" step where the intake meets the port. (the port being larger
than the intake)   I have an air die grinder but I never use it. I find my 3/8 drill to be much easier to use. Just my 2 cents

[James Buchan]

Why do you prefer the drill Hans? Is it control/speed or just a preferance?
I've never seen a port as rough as what a die grinder leaves before, I'll have to check that link out.

[Hansk]

Yes, slow steady speed , very controlable, lots of torgue, good grip,
less noise.
 They say they leave the ports that rough when it's there own heads,but customers don't like them like that so they make them look pretty witch
ofcoarse take time and time is $. But even then they do not polish the intakes, it's more of a sanded finish from a flaper wheel .  Has to do with
boundary layers etc. like Jim said.

[John W. Kelly]

Here's a trick that I use to make sure the manifold matches the head. I get a step stud (8mmx10mm) and hand ream the manifold so the 10mm end just bearly fits through. This way the assembly goes on the same way every time. It forms a sort of wedge-mate.

[Darren]

If you guys use electric Dremells rig up a Cieling fan rotary dimmer switch to use as the speed controll, The best Dremmel is the 2 amp Makita with 1/4\" inch collet. it's nice and light and big enough to hold properly with both hands(that's the draw back of using air grinders, too small to hold properly when heavy cutting) and the electric has gobs of torque. (around 175 bucks)

My method of port matching manifolds reguires the guides to be out of the heads as you perform the final match up with the 2 bolted together, and I use a 60 grit Cartrige roll on a 6\" shaft through the  intake port on the head. It takes a lot of practice to get the speed  the grinder controll so you don't dig trenches or bend the long shaft bits. Once I am happy with the fit I separate the Two and then use an air Dremmel (also with speed controll) with a Long 1/4\"shaft with a slit cut in the end to accept 80 Grit Emery paper (a strip about 5\" long rolled up clockwise on the end, I spin this through the port with a cutting fluid, ( Home made mix and top secret ) and it's not WD 40!  )     You have to get the speed just right to get the real showy finish...  Like Hans Says The final finish isn't the be all end all but I call it \"out of the box appeal for the customer\", if you pay the money you hope it will look great right,?  So I try to put a nice clean 80 grit finish on all my intakes. ( I like Standard abraisives emery as it has a real flexible cloth bach a the difference in final finish is noticable.

How far to port upwards? It depends on the manifold and the port on the head,in a nut shell a correct port will have a slight reduction in diameter all the way from the butterfly on the carb, to about 1/2 inch below the valve seat. if your intake track starts big, gets small, then gets big again or anything like that you are changing the intake velocity and this is not good, a nice tapered intake track accelerates the intake charge. ( so on this one I diagree with the \"Old One\")

Food for thought if you plan on porting you own heads for the first time,  Grinder 175 bucks, Speed controll  say $10,  Air Dremmel another $ 50,
I use  7 different Carbide burrs primarily all with 4-6\"shafts these will run you 30-50 bucks a piece for good ones,  Then theres the cartrige rolls and Mandrells,and .....and...and....

The FYI on the Standard abraisives website is also a very informative  how to ...
Happy grinding to all,

If anyone wants me to flow test thier heads(only Type 1) I'll do em for 25 bucks and that includes a graphical print out out (and we can compare to the hundred or so flow test from different VW heads in my ever growing database)

Chow for now. and have fun grinding!

[red snapper]

Hey Darrin, I have a set of heads that I would like to get checked over and your 2cents worth. Im not sure as to wether I will use them(valve seat came out). If your interested get back to me.Thanks Brian

[Billyisgr8]

Can you do singleport heads too?  I will be porting mine for a turbo 1600 and am looking for 130 cfm intake and 115 exhaust on 35 x 32 valves.  Eventually I will be going 40 x 40 when this motor grows to 78 x 90 but for now I will use the stock valves.

Kevin

[Hansk]

Hello Darren!  So is it the step idea you disagree with? They call it an anti-reversionary technique. They also talk about thier anti-reversionary seats, both of witch I've tried on my heads but I don't know what if anything it has done for me. I will take you up on the flowing offer next time I have them off.
 
Darren sure has a good point about the costs of trying this your self, but if your like me and you just can't keep your hands off ........