DIY Port and Polish

[Ghia Nut]

Since my engine has been down for almost a year, I finally bought another used block, AS21 FI case blah blah. I am also edging closer to completing my CB turbo blow through setup.

Any way I will be placing some forged 87mm slip ins and I will try to tackle my own port and polish job... So I have my flame suit on for people that dont agree with what Im going to do/attempt, I know I all ready have two strikes against me off the bat.

To start off Im not what I would consider to be a complete noob, but I am far from an expert. Ive learned a lot since being 16 and here on the samba and after trial error, vacuum leaks, stretched valves, failed lifters upgrades that worked or didnt I know my way around a vw fairly well.

I work for a college with a wonderful machine shop and I finally have weekends off to use said machine shop. This means I have access to some pretty nifty tools... expensive tools

To begin attempting this by hand, I have an 043 head that was etched/eaten/ruined by SuperClean. But Im going to turn it into a learning experience and begin porting and polishing.

First off the 043 head is 1600cc FI head so the intake is smaller... so what. That means more meat between the spark plug and the seats and hopefully more strength for boost. Im just trying to squeak a bit more out of these heads just for shits and giggles and learning, ALMOST anything is better than stock, I am aware that I can ruin these very rare examples of used heads... that was sarcasm btw. Ive read quite a few threads here about what not to do and if you have positive constructive criticism I am all ears.

In the mean time Ive been using reference pictures and 043s dont have extra meat behind the intake port mating surface towards the combustion chambers unlike CB's 044 etc etc. So I know I will have to be careful.

I wanted to use CB's Wedge Port and CAD it out but there is just not enough meat to do it... so I found some round port examples. I understand that I dont want to hollow the intake runners out but I want to increase the area heading towards the head... then match port. I do not have access to a flow bench or anything but I mean really whats there to loose?

So I concocted these port drawings up.

The black is a stock port setup, measured from the head and not the gasket... CBs gasket was pretty off spec... by a lot. In red is the port design I came up with and the bottom one shows the comparison between the two. I tried to keep it modest as some of the jobs Ive seen in the gallery have knife edge mating surfaces so I decided to be conservative. I dont want to do a fluff and buff, but I certainly do not want a stage 5 head job. So I took these drawings and put them on our laser cutter to make templates... Ill post pictures in a bit as Im still at the lab. I all ready have carbide burrs, and chineese grinding stones. I spent good money on the burrs though and will be practicing on the junk head tomorrow.
Pictures in a bit.
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'59 typ1 rajay turbo
'72 Ghia rajay 1641 dual 36DRLAs, 1 3/8" SS merged header and fat boy
78" GL Vert with ej22t swap
This will likely change tomorrow to something else.

[mark tucker]

dont use stones on aluminum heads. wach the aera where the intake flange meets the port below the intake bolt, that is where it will get thin porting it.just making biger isant the answer, unless you are making the motor biger too.it needs to be contoured corectly to maxamize the flow& velosity.big may increase the flow some but loose velosity.short side raidi like to be flat, thus the "D" port.there is a lot to portingcorectly there is a little to eff up a head.many things can alter the flow.Ive seen pro heads that were poop.and some that were totaly awassom almost unbeleavelable, and a lot inbetween.even seen heads with the ports compleatly removed and new ones being instaled.

[Ghia Nut]

I understand where you are coming from on bigger engines can get away with bigger porting due to larger displacements demanding more air through the ports. I should assume though that since my valve is actually tiny that funneling this into the combustion chamber that that is a limiting part, but making the transition from the throttle plate to valve needs to be smoother in transition and more direct. am I correct in this thinking?
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'59 typ1 rajay turbo
'72 Ghia rajay 1641 dual 36DRLAs, 1 3/8" SS merged header and fat boy
78" GL Vert with ej22t swap
This will likely change tomorrow to something else.

[krusher]

[ralf]

the templates look nice... if you check the classifieds
they do have some nice looking flange side pics


but always remember.. that flange aka head to manifold connection
is virtually not there, nor flow would care for it

have to picture the whole port/intake tract

from the top of the manifold (carb base) down to the throat = backside of the valve

.... some standard ideas u can use, follow to figure your own aproach

is the following

1- flow will always be faster on the short side turn vs long side turn
* there are ways to make this work for you.. or the head actualy lol

2- the farther u cut the top part of the port/entry flange
the farther that would be from the bottom most port entre (long side)
creating a bigger delta inbetween speed on the long turn vs short turn
*this can be worked around too.. as far as shaping goes etc

3- so the entry pics we always see and say wow... lol the half of the story is on the manifold hehehehe why most porters
offer the manifold portwork too as package or with discount ,


HTH

for pictures u may wait for rockcrusher as he will gladly share some
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Flow Through a Curved Conduit

porting my SP head for my brother's project
https://youtu.be/OS_mVjQuqgk

[fivelugshortaxle]

But not all pics will be shared.....
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Good things come to those who wait.
2332 with lots of goodies....
Rotating assembly balanced by Brothers VW
4340 84mm crank
AA 94mm p&c' s
Total seal 2nd ring, rest are Grants
5.5 h beams
Magnum straight cuts
Steve Long XR310 on a 106
CB 1.4 rockers
CB Magnaspark 2 distributor
NGK D7ea plugs
A1 lowdown 1 3/4 with single muffler
Dellorto 48's with 40 venturies
Kennedy Stage 2 with Daiken disc

[vwracerdave]

Porting heads is a science that takes years of testing and developement to master. It is not something you can learn by looking at a few pictures in a book. Without a calibrated flow bench all your doing is dancing in the dark.

The only true way to match port manifilds is when they are bolted to a head. A top quality head porter will not port used heads.
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2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK

[fredy a]

here is some reeding

http://knol.google.com/k/modifying-vw-type-1-cylinder-heads-for-performance#
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sorry for the spelling

[ralf]

[mark tucker]

RC has pics of cher??
I sent a set of used big chief heads to a well known head porter and there was no problem cnc porting them,of corse we had spent porbably well over $100000.00 with him. a good porter that wont do used heads(aluminum) might not be as good as you think,and is probably not as good as he thinks, but is selling his stuff,and possiably not his own work.nuff said on that. and yes a flow bench is a very good tool to use and learn from. I have found it dont realy matter what the head is for they all respond to the same thing about the same(excuding flat head)so if you have a flow bench and a few hundrad hours and a few heads you can learn a lot if you have some one to steer you in the right direction that knows what to do& how to do it.but just a flow bench dont make a perfect head.you can still effup a head badly and improve the flow.

[Ghia Nut]

Thanks for all the replies guys. I know this is going to be an interesting thread which is why I will be posting pics as I go.

Regarding airspeed/velocity... air can only be drawn through my 33mm intake valve so fast right so this is a huge limiting factor, now if I can more effectively direct that tract making the air path easier and more efficient, that's when the numbers come out.

I'll be posting pictures in a bit once in the shop...
_________________
'59 typ1 rajay turbo
'72 Ghia rajay 1641 dual 36DRLAs, 1 3/8" SS merged header and fat boy
78" GL Vert with ej22t swap
This will likely change tomorrow to something else.

[Buellistic]

Actually, the port itself is the main flow restrictor on stock heads. The small valves can flow a pretty good folume of air in reality.

I say go for it. You'll probably end up ruining the heads, but you could get a new or used set pretty cheaply. It's worth trying.

I did a super mild port job on my heads. I just removed any obvious bumps and smoothed out the port shape. I don't know for sure if it worked, but I could hit 4500rpm before it started losing pull.

I'm getting new heads from RC now though. I'll be able to make comparisons between newb work and pro soon.

[modok]

If you don't have a flowbench that's fine
Buy "pipemax" software and use it to figure out how big the valves and ports should be, as far as cross-section, for your displacement and rpm range

This will be a BIG eye opener, well worth the 20 bucks or whatever and your time spent figuring it out

[mark tucker]

a biger valve will always out perform a smaller valve in the corect port&chamber.straight out of the superflo flowbench book, and I agree.

[Ghia Nut]

Time for some updates...

So these were the heads from SuperClean eating the heads

And these were the templates I made on the laser cutter

carbide burrs, wish I had gotten a spherical one but what ever, they worked.

template on

big ass dremmell

used a scribe to lay out the ports

lots of this cutting fluid, really helped

first cutting was very iffy but I got the feel.

getting there

after some considerable time with the sander bit

I know I hit the valve guide but when Im ready to do this on the heads Im going to use I will press out the guides.

going to lath out a press bit for the arbor press with this

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'59 typ1 rajay turbo
'72 Ghia rajay 1641 dual 36DRLAs, 1 3/8" SS merged header and fat boy
78" GL Vert with ej22t swap
This will likely change tomorrow to something else.

[modok]

Leave the exhaust port alone!

It's too big already making it bigger won't help

[RockCrusher]

Good thing those are just for learning. WAY too much intake size for the valve in those heads. You're making the port VOLUME huge and when the valve opens the flow will be extremely lazy.....Proportion is the key to general purpose porting.
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[email protected] Please use email for all general inquiries.

I will be happy to speak to anyone who has a serious inquiry (meaning real potential business for RC enterprises) or a parts order. Due to machining noise causing missed calls all calls will be returned promptly.

[Ghia Nut]

thanks for the tips guys, I know I have a lot to learn and will reduce the size and look into that port program.

as for the exhaust port, I have a 1 5/8" header from CB, having that much of a step would create turbulence no? It is my understanding on exhaust that the exhaust side of things should be as smooth as possible.

And if any one is wondering. Im doing this to teach myself something and expand my knowledge about engines... Im not trying to start a company or sell these heads or anything.
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'59 typ1 rajay turbo
'72 Ghia rajay 1641 dual 36DRLAs, 1 3/8" SS merged header and fat boy
78" GL Vert with ej22t swap
This will likely change tomorrow to something else.

[RockCrusher]

Well....you are all ready learning.
You want a step at the exhaust flange. Yes the port can be mirror smooth on the exhaust. 1-5/8 header for a 31mm exhaust valve?

Looks like you took the bump out of the intake port just inside the entrance...very dangerous as that is the valve spring pocket under there. Don't do it.

RC
_________________
[email protected] Please use email for all general inquiries.

I will be happy to speak to anyone who has a serious inquiry (meaning real potential business for RC enterprises) or a parts order. Due to machining noise causing missed calls all calls will be returned promptly.

[Ghia Nut]

I bought the turbo manifold from CB, they dont make custom sizes so I was at their mercy as I like their location of the turbo.
_________________
'59 typ1 rajay turbo
'72 Ghia rajay 1641 dual 36DRLAs, 1 3/8" SS merged header and fat boy
78" GL Vert with ej22t swap
This will likely change tomorrow to something else.