Alright everyone,

After doing my 3rd GT head + cam swap i think iv got the Simplest/quickest way of doing it, Theres alot of people on here asking "can it be done" or "Will a GT cam fit in my 1043" so i thought why not do a quick guide on how to do it. This is the way that I think it best, I'm not saying it is but this was the easyest way for me. Also, dont come crying to me if you re-fitted your cam and did not time it up correctly, I have covered this area as best as i could but will no doubt not be enough for some people, Sorry if that includes you.

The engines that this guide will be most relavant to are the late mk2 hydro headed engines, All non Gt/G40 mk2f engines (No point doing it obviously), and some golfs.

Engines that the GT cam is compatible will include (Most common);

1043cc (1.05L)

Mk2 carb HZ - Polo

Mk2f SPI AAU - Polo

1272cc (1.3L)

Mk2 Carb MH - Polo/golf

Mk2 Carb 2G - Polo/golf

Mk2f SPI AAV - Polo

Mk2f MPI NZ - Polo

1391cc (1.4L)

ABD - Golf

1598cc (1.6L)

ABU - Golf

Any other engine requires special valve timing considerations, but as a rule these will also work

1.0

AER - Mk4 Polo

1.3

ADX - Early mk4 polo

1.4

AEX - Mk4 polo

APQ - Mk5 (6n2) polo

1.6

AEA - Early Mk4 polo.

AEE - Mk4 polo , skoda felicia etc.

Note, The GT cam will not fit into the mechanical headed early polo , A good way to quickly tell if you have one of these types is the fact that your rocker cover will be held on by 8 (or 10,cant remember) small bolts, If you have 3 larger bolts in the centre of the rocker cover holiding it to the head, the chances are you own a engine that will be compatible.

Another very important note, Depending on what engine you have, it will either have square tooth pulleys, or round teeth. (see pic of square tooth pulleys).

If your engine is from a mk2, it will have square tooth pulleys, If its from a mk2f(mk3) then it will have round, Make sure you know which one you have, Also also make sure you have purchased and fitted the correct shaped tooth pulley to your new cam!!, otherwise your fucked!

This is a square tooth pulley, found in mk2, Note square shaped teeth.

What gains will i get from swapping the cam to a GT one? (or simular)

The first mod i ever did to my AAU engined polo was to fit the GT cam, I had a test drive before and after.

After giving it a good thrashing after i had fitted it,i found that at low rpm it seemed moderatley more torquey, It would get upto peak power much quicker. At high rpm, 4500 - 6000 it pulled much better too, Generally making the car feel alot more sprightley.

How long will it take?

Depending on how mechanically minded you are it will more than likely take you around an hour and a half - 2 hours to swap out the cam.

(judging on how mechanically minded i was the first time , and how long it took me)

Do i need any special tools? What do i need?

No specialist tools are required to do the job (torque wrench optional) , A good toolbox should be sufficient. All you will need is the;

Gt cam (or whatever cam you are upgrading to)

Its a good idea to get the GT cam with the relevant pulley attatched. (explained later)

A new camshaft seal (Part number 117VG0140 from GSF car parts)

Step one:

Your engine should look more or less like this one, This is my HZ engine from a mk2, however all the engines listed above will look very simular to this. (note the 3 large bolts holding down rocker cover)

Before you do anything, disconnect your battery, This is so you dont accidently short something out whilst taking off the dizzy.

You also need to take the cambelt cover off, this is the plastic cover covering your cambelt and pulleys on the right of the engine :-D , Then, the first thing you need to do is to get your engine to Top dead centre on cylinder number one ( Cylinder one left looking from view above), This isnt hard to do so dont be put off.

This just means get piston number one to the highest point it will ever reach - Top dead centre.

To do this, you need to match up the timing marks located on your cam and crank pulleys.

The small dot on the pulley is marked with green pen, You can also just see the plastic arrow at the top left of the picture.

You need to turn over your engine untill the little dot on the outside of the cam pulley lines up EXACTLY with the small plastic arrow which is underneath the pulley on the inside plastic cam cover (see pic)

The best way to turn over your engine manually, is to do it by rotating the crankshaft pulley, To do this you need to apply full lock to the right on your steering wheel so you can access the bolt under your arch.

The bolt is under here, And looks like this

Once you have done this, look at your crank pulley which is the other pulley your cam belt is attatched to.

You should see that the little notch on your crank pulley is exactly in the middle of the cut out near your water pump.(see pic)

The space where the notch should be in the centre of should be somewhere around your water pump which is the thing in the top left of the picture.

If it isnt , you may not be bang on with your timing marks on the cam pulley, keep at it untill you get it correct, If you find it impossible to get them bang on, Your timing may allready be out!

If you get them lined up perfectly, Your engine is now set to TDC (Top dead centre), The reason its a good idea to do this is so you can re-fit the cam easily and trouble free, and keep piston to valve timing the same, Its easy to see if you have re-fitted it incorrect, You will see why further down.

STEP two:

Once both timing marks (one on cam pulley, one on crank pulley) are lined up with corresponding marks, You are now ready to start taking off the cam belt.

But first , undo the 3 large bolts that are holding on your rocker cover, This will reveal the camshaft and camshaft housings.

Now, tease off the cam-belt from the cam pulley, Be carefull not to damage it or mark it in any way.

The best way i find it to just grip it with your finger nails and go from side to side, edgeing it a few MM's at a time.

STEP THREE:

Now is the best time to take off your distributor, which is at the opposite side of your cam to the pulley. There is two bolts running horizontally, one above and one below the dizzy that is holding it on, these need to be taken out, which will then let you release

your distributor (see pic), it should just pull off sideways with abit of light force.

Once you have it off, place is carefully to the right of the engine bay, somewhere where it isnt going to get knocked or damaged, putting it in a plastic carrier bag is allways a good idea.

STEP FOUR:

This where you have abit of choice, but you may have allready made up your mind with how you have bought your cam. If the cam you have bought has come with a pulley attatched, i would advice that you extract the cam out of your engine as one (Not having to take of the pulley from the cam and extracting them seperate), this means you dont need to swing on the bolt that holds the pulley onto the cam so you can jimmy it out. Which brings me on to my next point.

You may have noticed that the plastic inside cambelt cover arcs over the camshaft on the left handside near the pulley (see pic), This is where you can have abit of choice what you do, You can either;

> Undo the bolt that holds the pulley onto the camshaft so the cam can be lifted out seperatley to the pulley

> or cut away the bit of plastic that blocks you from lifting the camshaft out of the engine,

The 3 times i have done this now, i have given up trying to undo the camshaft bolt, swinging on a bolt that stiff just scares me for alot of reasons, So now i allways just cut away the bit of plastic so that you can just pull the cam shaft upwards when it is released (see pic)

STEP FIVE:

You should now be able to see that if you undo all of the housings holding down the camshaft, there is nothing else holding it down.Now , this is part where you have to be most carefull. The camshaft is held down by 5 bearing/housings, And each bearing has 2 nuts holding it to the head.(See pic).

These nuts need to be loosend equally, I find it best just to start from one end , loosen each of the nuts on the first bearing a full turn, then move onto bearing cap number two and undo the two nuts a full turn, Then move to the third one and so on,

This will make sure you dont snap a bearing cap (easy to do), If one bearing cap was to feel the full force of all 8 valves pushing upwards, it would snap withing seconds, so undoing the nuts equally is vital.

After all of the bearing caps are loosend, the cam should pop upwards and be loose. Place all of the nuts and bearing housings somewhere nice and safe , Its a good idea to mark numbers on them, The left most one number one, whatever you do, dont get any foreign contaminents onto them.

You should now be able to lift the camshaft out of the cylinder head, Also place this somewhere safe incase you need to put it back in.

STEP SIX:

Obvioulsy , by now you should have taken off your cambelt, Ejected your exisitng camshaft and taken off your dizzy. Your engine should look something simular to this (see pic) ,Try not to get any dirt on the tappets that were under the camshaft, These are the 8 cylindrical blocks, These are the things the lobes act upon to push down the valves in your engine.

It is now time to fit the new camshaft, Make sure you have the correct tooth shape pulley on the new cam, And the bolt is very tight (60NM) , Also make sure that the camshaft seal is brandnew, You will have a moderate oil leak from that area if it isnt.

Now place the new camshaft where the old one came out, However, remember that the pulley has a timing mark on, Try and match this as good as you can to the timing arrow on the plastic housing , it will be hard because of the tappets resticting your movement, It doesnt have to be perfect but the closer the better, You will adjust to be perfectly on the mark soon.

Now, you can start to put the housings back where they came from, You should have numbered them when you took them out, or have put them somewhere safe in the order you took them out.Start by putting the middle one on first, and then screw on both of the nuts slightly, Just enough to hold it there, Then put housing number 1 on and do the same with the nuts, Then number 5 , then 2 and then 4.

This will keep the force nice and equal. You then want to tighten each of the nuts by a full turn, work from one side like you did when taking them off. Be very cafeful as the housing are easy to snap with them being very brittle. Once all the housings are tightened down, tighten them up moderately, I thinkt the right amount is somewhere around (6NM, but you will need a torque wrench to do this)

I hold my wrench above the actualy socket with one hand and tighen moderately (not on the actual handle of the wrench).

Now that your new cam is in place, and all housings are tight, your engine should look something like this;

STEP SEVEN:

The timing mark on your crankshaft should not have moved, If it has, just rotate it the same way you did to get the engine to TDC. You now need to line up your timing mark on your camshaft pulley to its timing mark (the plastic arrow) , you can do this by hand , just grab the pulley and line the marks up perfectly. Your now ready to push the cambelt back over the pulley, To do this, Pull the side of the cambelt closest to the windsheild nice and tight

And then pull the first few teeth ontop of the teeth on the pulley, Now just keep jimmying the belt back on, Use abit of common sence to get it back on, Maybe use a flat soft object to knock it back on, Its tight but will go back on eventually.

This picture shows where i had to trim back the plastic to allow the cam to be lifted out.

After youve got the belt back on, its now time to check the timing is still ok, Just turn the engine over manually , either using a wrench on the cam or crank pulley, When the timing mark on the cam pulley lines up with its corresponding mark (the plastic arrow), the notch on the crank pulley should be exactly between the cut out on the waterpump.

If the timing marks however do not line up prefectly, You are a tooth out and you need to take off the belt again and try again, If the timing marks line up then youve got it right, If you are even one tooth out of sync , the marks do not line up at all so dont worry.

Now, with both timing marks lined up perfectly its now time to test. Turn the engine over again a full revolution manually , using the crank pulley to do this. Turn it over and see if the marks line up again, (they no doubt should) but its good to check. Do this a few times to make sure, (i usually do it about 10 times) but thats because i like to make sure its timed up right.

So, Now that your all timed up again, your ready to re-fit the distributor in the opposite way you took it off, and re-fit the rocker cover.

Make sure all of the clips that were holding on your cambelt cover are no where near your belt and pulleys, These may get caught in the teeth and render your engine scrap. Put the cover back on for the time being.

You are pretty much finished now, re-connect your battery, and fire her up.

Take the car for a test drive and see what you think. If it doesnt seem to be much different, Chances are you have re-fitted your distributor slightly retarded (not what you think).

Undo the bolts slightly that are holiding the distributor, when the engines off rotate it anti clockwise or towards you (same thing) and tighten up the bolts, this will advance your igntion timing , Do it slightly, re-fit your dizzy and then take for another test drive, Keep doing this untill you feel like you have gone abit to far and the power has started to drop off, Or it becomes hard to start or the engines starts pinking.

Any questions please ask, And please point out any mistakes i have made, I've wrote this over a few days and may have missed something.

Hope this helps and that your happy with the outcome.

Max

DOES THE GT CAM FIT INTO MY Mk4 POLO'S ENGINE?

The cam will fit into the later mk4 8v engines yes (with complications), Engines's its compatible with;

MK4 1.0 AER (POLO)

Mk4 1.4 AEX (POLO)

Mk4 1.6 AEE (POLO)

The problem with fitting the cam to theses engines are the fact that the cam was not designed for this size block/stroke , meaning that the timing is out. The way to fix this is with a vernier cam pulley.

Edited 30 September, 201213 yr by MaxGT

Great guide, have been thinking of doing this for a bit. Will be on the look out for a GT cam come pay day :). I have an AAU, do you know if it would benefit from swapping to a GT dizzy as well?

No the GT dizzy woundnt be compaitble with your AAU mate,

It a pretty much bespoke item to the GT.

Great write-up! Does the fuel pump work OK with the GT cam on a Mk2?

Yeah the facet is great mate.

Just need to cap off the mechy fuel pump and plumb in the facet. Took about 30 mins.

nice write up dude. ill be doin this soon :) the only thing id do different is mark the position of the dizzy before you take it off so you can refit it in exactly the same place so your timing will be the same.

mabbo

Hi there,

I'm new to the forum, I've just upgraded from a saxo to a mk2 polo :-D

I'm no good at doing mechanical stuff, you fancy doing mine for me if I get the bits? I could do you hair and make up in return

This is an ace guide, good work!

I'd only add that it's a good idea to use gasket sealant under the two outer cam journals (1&5). I didn't bother when I did mine, and got a little leak on either side. Not really essential but might as well be done.

Also the torque rating for the cam journal bolts is 6nm rather than 60nm, and can be done by hand like you say.

Edited 15 October, 201015 yr by callum.

will a gt cam fit my 95 6n polo 1.3 spi ??? :-)

nice write up dude. ill be doin this soon :) the only thing id do different is mark the position of the dizzy before you take it off so you can refit it in exactly the same place so your timing will be the same.

mabbo

I thought about that mate but you benefit alot more by advancing your ignition timing so marking it wouldnt be any use.

Thinking about it, its a good idea lol , its where you can go back to if you fuck it up.

Max

Hi there,

I'm new to the forum, I've just upgraded from a saxo to a mk2 polo :-D

I'm no good at doing mechanical stuff, you fancy doing mine for me if I get the bits? I could do you hair and make up in return

Id be happy to, where you live? Make up sounds great.

This is an ace guide, good work!

I'd only add that it's a good idea to use gasket sealant under the two outer cam journals (1&5). I didn't bother when I did mine, and got a little leak on either side. Not really essential but might as well be done.

Also the torque rating for the cam journal bolts is 6nm rather than 60nm, and can be done by hand like you say.

Yeah thats a good idea mate, ill add it to the additional list haha.

did you not fit new tappets?

Id be happy to, where you live? Make up sounds great

I live in a place called thurcroft, about 10 minutes outside Rotherham.

I'll get myself on ebay for some bits and stock up on makeup, what colour do you want your eyes doing?

did you not fit new tappets?

Nah , Its says in the Haynes manual that it isn't necessary unless the original cam was defective.

Id be happy to, where you live? Make up sounds great

I live in a place called thurcroft, about 10 minutes outside Rotherham.

I'll get myself on ebay for some bits and stock up on makeup, what colour do you want your eyes doing?

Oh yeah, iv got mates from there.

Id be happy to do it for a few bucks.

Max

Added information on fitting a GT cam to later mk4 8v engines.

Remembered some information about fitting the cam to the 1.4 ABD golf engine aswell.

I never bothered changing the tappets on mine when I swapped the cam (into a 1.4 ABD) I just ran the engine for a long time (20-30 mins) idling to let everything settle down.

Great guide mate! :-) Only slight niggle I have is that it is VITAL to use a torque wrench, not optional haha. Also it's best to use the correct loosening/ tightening sequence on the cam bearing caps, rather than just one end to the other.

nice write up dude. ill be doin this soon :) the only thing id do different is mark the position of the dizzy before you take it off so you can refit it in exactly the same place so your timing will be the same.

mabbo

I thought about that mate but you benefit alot more by advancing your ignition timing so marking it wouldnt be any use.

Thinking about it, its a good idea lol , its where you can go back to if you fuck it up.

Max

Ey up Max,

I'm not sure how many degrees the timing should be set at on a Polo off the top of my head, but I wouldn't suggest anyone just guess how much to advance the timing because too much timing can cause detonation etc. which aint cool. You will prob be safe advancing it a few degrees but I wouldn't go crazy, because even though the engine might feel like its running well, you are risking it pinking/melting a piston etc.

Cracking writeup tho dude :)

Mabbo

Great guide mate! :-) Only slight niggle I have is that it is VITAL to use a torque wrench, not optional haha. Also it's best to use the correct loosening/ tightening sequence on the cam bearing caps, rather than just one end to the other.

Cheers jon.

Yeah, a torque wrench is the best way.

Also, the proper tightening sequence uses full turns so doing this is pretty much just as safe with it only being half turns. It also needs a torque wrench and the correct sequence which not alot of people have access to.

nice write up dude. ill be doin this soon :) the only thing id do different is mark the position of the dizzy before you take it off so you can refit it in exactly the same place so your timing will be the same.

mabbo

I thought about that mate but you benefit alot more by advancing your ignition timing so marking it wouldnt be any use.

Thinking about it, its a good idea lol , its where you can go back to if you fuck it up.

Max

Ey up Max,

I'm not sure how many degrees the timing should be set at on a Polo off the top of my head, but I wouldn't suggest anyone just guess how much to advance the timing because too much timing can cause detonation etc. which aint cool. You will prob be safe advancing it a few degrees but I wouldn't go crazy, because even though the engine might feel like its running well, you are risking it pinking/melting a piston etc.

Cracking writeup tho dude :)

Mabbo

Cheers mate!

All of my engines i have ran and a lot of people i know have used nearly full advancement and iv never had any problems.

Pinking and detonation would definitely be noticeable though surely? And that's obviously when you need to stop.

Thanks again.

Timing gun FTW. Someone stick this in the FAQ already!

Done!

Yeah you have to have a timing gun of some sort to set the base advance, then you can start increasing the base advance to see if you get any improvement. You may see some improvements on older engines that were designed to run on 91ron fuel. But a few extra degrees is the most you'll want to go.

I need a timing gun