diy port polish 8v

ive really fancied doing this for a while, and got the head off my spare on saturday


its in really good nick for having done 130k, im going to renew everything but the valves cos theyre looking sweet (so far, i havent got them out yet) with no pitting, spring compressor comes 2mo

ive used so far a wire brush on a drill, variious grades of wet n dry down to 800, wire wool and loads of wd40

this face before


after



ive checked the head for square wi a metal rule and didnt go to deep to get gasket marks off, reckon flats better than shiny!!!

had some trouble getting the exhaust manifold bolts out till i locked two nuts up 12mm


last night i cleaned up the inlet face , im gonna offer up the new gaskets, scribe them off and reduce the bores to that mark.  i want to try using internal calipers to make each of the ports equal per cylinder



valves are coming out 2moro then ill start grinding back the ports

Some nice work there - yes flat is better   

got the exhaust manifold gaskets this morning and scribed the shape onto the block


used the old bolts to pin the gasket down, tis easy to see how much to remove


scribed round the gasket, this will act as a maximum level, will grind down to just within this line


ive labelled the gaskets and done them individually so i can use them to mark the manifold later on

polished the side (again!!)

Thats very nice so far, as well as match porting the manifolds are you going to do anything behind the valves where the real power gains are?

do you mean behind the valve seat, if so then yes but really carefully cos i dont want to take off too much!

just got my valve spring compressor, pics to follow!

I'm likin this! more updates! plz!

Hello

Yeah behind the valve seats is where I mean, You can also take a bit off the valve seats not much but around mill.

When I did a 16v head for a mate I had the valve guides pressed out first so I could really get in at all angles and then got nice new guide put back in. Also the seat were re-ground for the new guides to be central and this prosscee removed any slips I had made.

Also before I had the guide put in I spent alot of time polishing the ports with wet and dry can remember what grade I used but I was virtually a mirror finish (students that have no beer money have enough time to do this)

Regards
Rich

ok got the valves out, when compressing the springs, you reach a point of high pressure just b4 the cotter seal breaks, was abit alarming first time so i slowly increased pressure till they went

shot of the cotters


ive got labelled boxes to put everything into so they all go back in the same ones


all out


see the amount of crud in the exhaust port, tis pretty thick in there




how did you get the guides out m8, is there any way of doing it yourself??

next stage is to clean up the valves and order new springs.

Hello

It is possible to get the guides out your self but its tricky. To start with u need a nice suitable press and a good set of drifts and punches to press them out. They come out the top of the head towards the cam shaft. But also you need to warm the head up and make it loosen its grip on the guides. I have done this before by putting the head in my mum's aga baking oven for a few hours. the temp in the oven was about 200 degrees C maybe more. After I put the new guides back in I then had the head skimmed and the seats re-ground, re-grinding the seats is esetnail as I garanntte you that the new guides wont be central to the seats any more.

The place that use to do TSR's engine work like that charge 6 quid a guide to be fitted and i think its 3.50 a seat fro re-grinding and ?40 for a skim

Hello again

Also polishing up the ports will stop the build up of carbon in the exhaust as the surface roughness average is much lower it has less chance of sticking and getting inbeded in the little dips and bumps. But what really helps reduce the build up will be the new guides and stem seals and a correctly set mixture but if the piston rings are worn then will still build up but no where near as much.

Regards
Rich

yeah fully intend to highly polish the ex ports. am still thinking about wether to take out the guides, will do some research on where to get that done.

did you remove the injector shrouds, they seem to be the biggest flow disruption imo

made a start on the porting done these 2 inlets what dyou think




compared to these two that i havent done yet

nice so far chap. what tools are you using? Demmel and a drill. I used my drill for the big metal shaving jobs and the dremmel to get the final results.



This is with the big stone on my drill.



I didnt get pix of the final finish. just some of the main prep.

Love to see yours in the finished state.. keep up the good work!

nice work too mate, but u rckon that didnt make much difference?? :dontknow:

excellent job.. keep the update & pics comming..  8)

I made a nice difference to my 1.6 carbed version. Lots more power and it revs right up into the red and pulling all the way. Before it used to blow off at 5500rpm and had to change up. Typical golf 8v..lol

Funny ya know one of my m8`s is VW mad and has a golf Mk2 8V GTI and i got his to do now after before and after road tests.with mine..lol
He has some spare heads and for doing his, i get one free to play with.

The only a couple of thing i wished i done to mine, when it was on the bench was backshing the valves and doing some work of valve shrouding. Its to take a bit off around the chamber nearest to the inlet and exhaust valves. Its quite close on these heads. Its  just a little CFM increase but all of the litte increases make a bigger difference.

here is some info on the subject. Beware there are a few pages. but great reading.

THANK YOU

thats wkd cheers

very nice, interested to hear what it goes like when all done.
 IMO i would have the valve guides changed as chances are they've done the full 130k and are worn !  the valve gives up most of its heat through the guides, not to mention the crucial role of seating!

 great post, keep it comming

rdub

i was gonna fit it this weekend as ive got loads of other work being done on her including a polished inlet manifold, but that would have been rushing so now ive decided to wait till summer and get the valve guides replaced as u reccomend.
i think im showing my age tbh!!

I have a stage 3 port and polished head (tsr) for a Dx code engine.

Sensible offers only.

Patrick