8v DIY Head Porting???

[skyline.99]

Hi peeps!! I own a 1.4 8v and I was wondering wether any of you guys had attempted a port polish and clean yourselves with a dremel like tool?
I seen a couple of websites which show you the basics and it doesnt look all that hard
However Im still worried about ruining my head as ive never done it before . Would it be an idea to buy another head just incase?? Anybody had this work done professionally??

Maybe I should start with something smaller... My 70cc Midi perhaps

Any helps appreciated, STeve

[bstardchild]

Hi peeps!! I own a 1.4 8v and I was wondering wether any of you guys had attempted a port polish and clean yourselves with a dremel like tool?
I seen a couple of websites which show you the basics and it doesnt look all that hard
However Im still worried about ruining my head as ive never done it before . Would it be an idea to buy another head just incase?? Anybody had this work done professionally??

Maybe I should start with something smaller... My 70cc Midi perhaps

Any helps appreciated, STeve

Very little to be gained from this - you'll have to take my word as someone who bought a spare head to investigate the options.

Polishing is a total waste of space as it doesn't gain any power!! Tuners only do it so it looks pretty and people think a lot of work has been done - if you talk to any reputable tuner he'll tell you best finish is actually a finish similar to a sandblasted effect!!!

Porting the inlets and the exhaust ports is also pretty much a wast of time too on the 1.4 8V engine

The reason is the plastic inlet manifold is a restrictive in terms of port size as the head!!!

Valve area and port throats can be improved to maximise flow and compression can certainly be increased a fraction - thats what I intend to do to my spare head.....

It's not restrictive on the exhaust side from what I have looked at so no need to do anything there

HOWEVER (this is important)

The biggest problem is you need to compensate in the ECU for any changes you make and thats where I will start first!!!

Once I find a spare 1.4 8V AEX ECU that isn't going to cost me an arm and a leg

[skyline.99]

Ahh i see! I have the AEX engine too.
I seen rothe motorsport do a turbo(127ps)/supercharge(167ps) conversion for this engine but v. expensive.
I have also seen on a website a larger inlet manifold for the AEX but there is little info about it. Its on http://www.ten24.co.uk/aat/index.php?cPath=84_27_53
I wonder if this would make any difference to the restrictive plastic inlet manifold you were talking about, and would it make porting worth it?

Also what kind of mods are you doing to the ECU??
What about a 16v head conversion? Do you think this is possible because i dont think ive seen one yet. I think a 1.4 16v turbo would be lovely. I know a lot of work would be involved for the 16valves eg. new inlet manifold, exhaust manifold, timing belt but these are only the obvious ones to me.

Any ideas

Much appreciated!!![/url]

[skyline.99]

oh yes and of course how about new head

LOL

[bstardchild]

I seen rothe motorsport do a turbo(127ps)/supercharge(167ps) conversion for this engine but v. expensive.

I bet!!!!

I have also seen on a website a larger inlet manifold for the AEX but there is little info about it. Its on http://www.ten24.co.uk/aat/index.php?cPath=84_27_53

I'll have a look at that tonight

I wonder if this would make any difference to the restrictive plastic inlet manifold you were talking about, and would it make porting worth it?

Maybe not neccesarily porting more blending to match a bigger manifold

Also what kind of mods are you doing to the ECU??

What I always do - Increase fueling and modify ignition maps - it's fresh air from 4000 rpm on thats why the engine is so reluctant to rev past 4500 and then take out any obvious emissions and noise related holes in the maps plus re-write the checksum so you don't get the management light on!!!

What about a 16v head conversion? Do you think this is possible because i dont think ive seen one yet.

Nope - blocks have differences I think plus other issues if you want a 16V its a transplant job

I think a 1.4 16v turbo would be lovely. I know a lot of work would be involved for the 16valves eg. new inlet manifold, exhaust manifold, timing belt but these are only the obvious ones to me.

Piston shape will be different and it's higher compression ratio if you want that sort of power - transplant is the only economical way - modifing engines is not cheap.

Any ideas

You've got em all!!!

Much appreciated!!!

No problems

My target is 85-95 bhp with all the mods I plan to carry out but I want to modify the head last to see what you can get with bolt-on parts changing

ie

De-cat
Bigger TB
Bit of induction work - NOT a K&N filter on the TB!!!
and a re-map

[skyline.99]

That larger intake manifold is for use with carbs i think? Says for use with 40DCOE's and i looked that up and it looks like a carb.
What i might do it assemble my own turbo job.
Do thicker head gaskets actually work to lower compression and are they reliable? with forced induction would porting/polishing make any difference, as the air is forced anyway??

Cheers matey!!

[bstardchild]

That larger intake manifold is for use with carbs i think? Says for use with 40DCOE's and i looked that up and it looks like a carb.

OK - scratch that then

What i might do it assemble my own turbo job.

Brave

Do thicker head gaskets actually work to lower compression and are they reliable?

Yes and Nope not 100% reliable but it depends on what they are made of

with forced induction would porting/polishing make any difference, as the air is forced anyway??

Help to reduce negative boost but as a general rule if you are force feeding the engine porting and blending makes a very small difference compared to the difference a blower makes!!

[david burton]

When I joined this forum I'm sure I heard of some examples of a 16v head on an 8v. but this is from distant memory.

[wils0n86]

I looked into doing this on my 8v, and I was told that the 16v head would not work as it had a different compression ratio - thats the easiest bit ov the explanation i understood

[bstardchild]

When I joined this forum I'm sure I heard of some examples of a 16v head on an 8v. but this is from distant memory.

I think - it only works on one engine code and it's not AEX!!!!

[skyline.99]

As for the gasket i was thinking copper. Maybe get 2 stock gaskets and sanwitch it all together !? lol

[Phatman]

What if you used the 16v pistons too?

The exhaust manifold looks a bit basic on the 8v, maybe a 4-2-1 would bring a bit more power to the top end? My engine is an APQ and it's easily as fast as my old 1.6 Cordoba, makes me wonder whether the 60BHP is accurate!

I looked into doing this on my 8v, and I was told that the 16v head would not work as it had a different compression ratio - thats the easiest bit ov the explanation i understood

[skyline.99]

As speedlaw said a 16v head wont fit the bottom end of most of the 8v engines. The holes for water/oil will not line up proper.
I have been looking round for other methods of increased power and one of the cheapest ive found so far is this..
get a m45 eaton supercharger which is available for around 100 pounds, get a custom made pipe to come off that to attatch to the TB.
Of course mounting it to the engine will be the b***h, and also gasket will still be needed to lower compression ratio enough.
That supercharger is off the mini cooper S and theres lots floating about. I will also need an intercooler(new front bumper please!), and some nice hosing to go around the engine. Another difficult part is calculating the rpms for the supercharger. Its a direct drive from the engine so depending on the size of the minis crank pulley and vw 1.4 aex crank pulley adjustments may have to be made to the charger pulley.
As for mounting i was thinking for the front below the ex manifold.
I dont know about drive. Maybe a custom crank pulley with extra belt drive. I seen this on ice cream vans, though dont know if theres space in the car.
Speedlaw as you are the ECU wizz can i ask you-
Say fabricated this set up and the charger was mounted ok and it was boosting about 6-8 psi. If nothing was done to the ECU could you guess how the engine would react? I mean, If i did strap the S/C to the engine and all was well, would i be able to drive it to get it chipped up properly???
Im guessing the total cost of this job (including a lot of time n effort) would be about £6-800.
As for power i have no idea what the engine would produce. Speedlaw have you got any idea how much power the stock internals of this engine can take?? (AEX)

Safe B

[JarnoVWPolo6N]

Very little to be gained from this

sorry, but I really need to disagree, the inlet and outlet ports (and complete cilinderheads) from all polo engine's are a very good place to win power and torque. Most reputational tuning companies over here give an estimate of MINIMALLY 15% gain in power and torque, so if your engine is very 'powerless' from the start (which Polo-engines are, except the GT, G40 and GTI engines), and combine cilinderhead flowing with a new cam, motorbike carburettors and a spaghetty exhaustmanifold, a regular 1,6 mpi (AEA engine) went from 75 bhp to 109,3 bhp (a +45% increase, without turbo or supercharger whatsoever) torque increased to 154Nm.

All this was installed on the 6N of a member of the Dutch Polo Club, and all was done by himself and another Polo-fanatic (incl. the flowing and polishing of the cilinderhead), without any help from any tuningcompanie

so there is definately something to gain from flowin and polishing your cilinderhead

( here's the link to the topic about this 'project' http://www.vwpolo.nl/forum/index.php?showtopic=2065 I know it's in Dutch, but the pictures and figures (from the dyno-test) will make my point clear )

[skyline.99]

Link appears to be dead mate?
Also my mate suggested to get bigger valves from say a 1.6, and get my 1.4 head machined to fit these valves. Sounds like a great idea to me! Suppose theres only one way to find out.. unless one of you nutters has tried this
Are there any larger throttle bodies/intake manifolds (perhaps from a 1.6?) made for these engines as a bolt on upgrade or will it have to be custom?
Maybe something from another car but who knows what!