headwork - before and after pics please

[jimbob-mcgrew]

i searched a fair while, and found what i was looking for in a 2004 post by krobinson, but no viewable pics unfortuantly.
i went to extreme of spying on the poor bloke, and searching his photobucket for the lost gold-dust, but no joy.

i want to do some headwork myself, i dont know a whole lot about the whole process, but i understand you dive in with a little grinder and take away the restrictions.
turning the circular inlet ports of the 14se into cathederal shape for instance, to match my manifold, and anything internal worth doing ?

any before and after pics + tips, would be awsome cheers :thumb:

i was going to put a 14se head onto my 13s, but from what i understand i'll be better off using a 14 bottom aswell, as the valves are mighty close to the block walls.
what about the cam from my 1300 to replace the sri ? might be the only piece worth keeping to use ?

[Southie]

Just sent Keith a PM so he's maybe able to help you out... you stalker lol

[philip]

drop me a text and i can email you some of a 16se head i did, shows before and after very well i did for a lad. all on mobile but in work soon so no time to load onto comp. 07807 040522

[MK999]

Jimbob, if you drop me a PM, I'll go through the basic process with you. To do it properly though you need a fair bit of kit, as every head is slightly different, but I don't mind listing the general basics for ya.

[philip]

no order as photobucket has changed again
http://i59.photobucket.com/albums/g312/philbug/IMG-20120126-00498_zpse35c9117.jpg
http://i59.photobucket.com/albums/g312/philbug/IMG-20120126-00496_zps01f03103.jpg
http://i59.photobucket.com/albums/g312/philbug/Flintshire-20120109-00439_zpsf621b3bf.jpg
http://i59.photobucket.com/albums/g312/philbug/Flintshire-20120109-00436_zps05f73163.jpg

[philip]

http://i59.photobucket.com/albums/g312/philbug/Flintshire-20120109-00429_zps4972df56.jpg
http://i59.photobucket.com/albums/g312/philbug/Flintshire-20120109-00424_zps97c28ec6.jpg
http://i59.photobucket.com/albums/g312/philbug/IMG-20120126-00495_zps2839ed3b.jpg
http://i59.photobucket.com/albums/g312/philbug/Flintshire-20120109-00437_zps050df631.jpg

[jimbob-mcgrew]

cheers all :thumb:
those pics make it more sense to me now, the fuel and air go in and shoot downwards, get locked in and ker-bang, world war II, then get released and shoot upwards for exhaust port.
from what i can see youve shaved the guides out from the inlet ports aswel as the exhaust ports. can you get away with that much metal, without cooking the valve stem or stem seals ?
did you chop a large chunk out the combustion chambre too ? i was expecting to see a triangular shaped break between the valve heads. ive probably missed a fair bit as im not quite sure what im looking for. looks good tho, cheers

[meritlover]

MK999 has probably covered most of this, but here it is for others anyway.

The main points to observe is the amount of blending between the valve seat and the head. its seamless with no steps or ridges. This is a one step easy improvement to these heads as the factory finish here is pretty savage. 3 way cut seats will also help the flow across the sealing face but added expense.

you will have no issues with cutting back the valve guides as long as they are in decent condition. There is little to be gained as i think they taper down to next to nothing anyway.
Some of those pics looks like the guide is removed completly/not fitted yet, but would be fine to buff it flush with the port. just remember to flush it all spotless from swarf afterwards!

i wouldnt go madly enlargening the ports. Theyre pretty much big enough already. Just make the flow more laminar and give those gasses an easier time and make them all the same. The last thing you want is to end up with a cylinder with better VE than the rest. You can only tune as far as your worst cylinder will allow anyway...if you dont, your best flowing cylinder will likely blow up first.

The next most important thing that is always over looked is the manifold and port matching. ive seen heads attacked with dremels that look great...only to find the manifold ports and gasket over lap by about 2.5mm into the port. Ideally it should be matched and doweled. But just do all you can to make sure when theyre seamless joins when the flanges are butted up.

i love head

[therealnovaboy]

[

those pics make it more sense to me now, the fuel and air go in and shoot downwards, get locked in and ker-bang, world war II, then get released and shoot upwards for exhaust port.

There is a lot more to it than that. The biggest problem with the 8valve head is the short curve on the port floor. The back of the curve creates a void area where the air does not fill, and therefore an area of the valve that is not used as effectively. To compensate for this void where the air traveling along the floor does not reach, headwork is focused on dropping the port floor and the short radius curve, and raising the port roof. This reduces the curve in which the air has to travel along the floor of the port and creates a more direct angle of flow to the valve.

Many ported heads you see are starting to replicate the cathedral shaped port design of the 1.2 heads. This reduces the speed of the air flowing along the bottom of the port floor, and encourages the air to tumble down the short radius curve of the port. The ports are also offset to the valve to encourage swirl filling of the combustion chamber. The air is encouraged to follow the left hand side of the port and the roof to curve round the front of the valve (or a clock wise direction if looking down the inlet) and use the whole area of the valve seat. This also helps the filling of the combustion chamber.

In the combustion chamber the air fills in a swirl towards the flat of the kidney shape on the head. The flat edge is designed so that when the piston comes up it squishes the air towards the spark plug and helps to create an even flame front.

It’s not so much an explosion but a long steady burn in comparison. As the piston comes up on the exhaust stroke the exhaust valve opens and the squish of the piston pushes the exhaust gas out the exhaust valve.
It gets more complicated when you introduce valve overlap where the inlet valve opens while the exhaust valve is still exhausting to help suck the air in the inlet and push the exhaust gasses out.

[philip]

I removed the casting around the guide when the guides were removed, one of the pics should show the ported inlet with a new guide in. There wouldn't be any problems with valve stem or seal matey, some people port the original lump around the guide to direct flow, but ran headslike the one above on some screaming 1600's nd make good power. What do you mean chunk out of the chamber and triangular break? Lost me abit.

[meritlover]

DO NOT TOUCH the combustion chamber.

its not just about flow, its about air speed. If you make to ports too big the airspeed will be too low for the same flow rate so you will suffer more drop out and less tumble/mixing.

bigger is not always better.

Would be nice to see pics of 'pro heads' if people have them. Randomly carved amateur jobs are less useful to refer to.

[philip]

I'm on my mobile, but are the pics showing the full port? Mobile only shows half of the pictures, as said the pics aren't in an order, just what I could load up before work, that head only had single angle cut on the seats, but you could go as far as full radius, but a waste of money on anything like this. You could blend the top of the seat into the chamber and 'deshroud' around the back of the valve if need be. As nova lad has mentioned, the bottom of the 8v ports are at an almost right angle, which is no use, you can carefully remove some material from it and raius the short/bottom of the port to help this.

Some of the pics where you can see a guide is because there isn't any fitted, I ported the head then fitted the new guides to keep full length, but there's always an option to cut the exsisting guide into the port or do as I've done and replace them after heads been ported.

[philip]

My heads aren't 'randomly carved' done a few bits for bowyer in the past;) and I also built a few very competitive 20xe's + let's.

[meritlover]

My heads aren't 'randomly carved' done a few bits for bowyer in the past;) and I also built a few very competitive 20xe's + let's.

i didnt mean your head. i meant more properly done heads. i did realise after i wrote that that it may have sounded disrespectful

[philip]

H fair enough matey, I've seen exon race engines 20xe head, ric wood + cyl head ev heads in person and the work has been very poor, especially for what mates had been charged. Neil roper/bowyer/simon armstrong do very good heads, never rated the blydenstein heads either(sorry if spelt name wrong)

As has been said, people have the perception of 'bigger is better' with heads and I've seen a fair few which people have had a go and broken through into water/oilways, best thing to do is strip your head, identify rough/sharp edges, step between valve seat and port and the bottom/short radius and just lightly fettle the areas to smooth them out. Don't go mirror smooth on the inlet port, finish it with 80grit or 120, wants to be smooth but coarse(hard to explain) haha, years ago people would ask for a ported + polished head and if the inlets weren't like a mirror they would complain, little did they know it caused poor atomisation of the fuel and cause it to pool and suffer poor combustion

[pete17]

[QUOTE=philip;2120075]H fair enough matey, I've seen exon race engines 20xe head, ric wood + cyl head ev heads in person and the work has been very poor, especially for what mates had been charged. Neil roper/bowyer/simon armstrong do very good head, never rated the blydenstein heads either(sorry if spelt name wrong)

hmmm so do they (sorry but had to do it) lollollol

[jimbob-mcgrew]

atomisation :)
about the guides, i wasnt aware they were seperate - ignore what i said, im an inexperienced numpty lol
talking about hitting waterways/oilways - how far do you reckon you can get away with on the short pass ? as it looks like im going to need to take about 3mm away port side, to match the cathederal ports, then from there, i need to blend the path between, without going mad and breaking thru (that would suck)

[garyc]

Search for David Vizard on amazon, he has a new book out that explains it all.

[jimbob-mcgrew]

http://i289.photobucket.com/albums/ll227/photon_09/additional/1.jpg

like this when there inserted back in phil, i get ya now.

[jimbob-mcgrew]

found a decent guide on a vw site actually, step by step airflow figures, pretty good read.
i doubt id be able to take that 3mm i wanted for the cathederal without hitting waterways, plus i understand that road cars should be left smaller, as it will rob the engine of low down power due to less vacuum build up.
is it possible to use some sort of chemical metal stuff on the manifold side to 'build up' the manifold so i can go the other way and form it circular to the head, ally cant be welded easily can it ?

hmmm, im finding out, theres way more to this that just improvements.

[meritlover]

it is possible to use epoxy or 'chemical metal' and it is often done as you say, to add to one side when you cant take away for another. But, you have to ask yourself if its worth the risk of it loosing its bond, falling off through the valves and into the combustion chamber and wrecking your top end?

the above pic looks like a 16V head where the siamese ports can be knife edged

To be honest, without knowing what you're doing you are likely to make the ports worse or waste a good head. Keep it simple.

remove the rags around the valve seats (this is probably where the biggest one off gain can be made)
give it an over all smoothing,
tidy up the manifold and check the flanges are seamless with no protruding gasket,
grind in the valves.

[philip]

that pic is off ric woods website (cncheads) most heads have had tpo be worked further after hes 'worked' them, always come up forsale on british rally that martin, jre, etc have had to do further work, alot of money when dont seem all that, just more bragging rights imo