8v DIY Head Porting???

[bstardchild]

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.

I took one look (actually several but it doesn't matter) at the ports in the head and the inlet manifold (plastic one) on the 1.4 AEX engine and realised that you could port the head to buggery and still get no benefit - the inlet manifold dimensions are not going to allow much if anything in the way of improvements.

And I've ported a few engines over the years normally with gains of 10-15% It's normally obvious where gains can be made

[skyline.99]

[quote="bstardchild"][quote="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.[/quote]

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

Any idea which engine code this is?? sounds interesting

[helios1]

Is it possible to do a 16v head swap on a 1.6?

Sorry if its a stupid question, im not entierly clued up on engines

[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.

I took one look (actually several but it doesn't matter) at the ports in the head and the inlet manifold (plastic one) on the 1.4 AEX engine and realised that you could port the head to buggery and still get no benefit - the inlet manifold dimensions are not going to allow much if anything in the way of improvements.

Ok, got to admit your right about the inletmanifold of the AEX and AEE engine's, them suck, big time

And like I said, head flowing will have great potential, but it won't make that much difference if you don't "add the other ingredients" for power and torque (cam, exhaustmanifold, de-cat, inlet-optimisation), then it will really have good effects.
So, the solution, flow your head, and get a new inletsystem (motorbike carburettors (Suzuki's are common used as fas as I know) or the inletsystem (manifold, throttlebody, injectors and ECU) of a Polo GT with enginecode 3F, this will surely make a great difference, since the inletsystem of the 3F engine's is the most 'powerfull' on ever produced in a Polo, inletmanifold is even bigger then a G40 one )

[helios1]

Hey Jarno, youve got a 1.3 right? Ive got one, its engine code is ADX. How much you hoping to get out of ur engine?

[JarnoVWPolo6N]

Hey Jarno, youve got a 1.3 right? Ive got one, its engine code is ADX. How much you hoping to get out of ur engine?

pfouh, god question there m8, well, let's see, got a camshaft from a Polo GT with enginecode 3F ready, gonna get a supersprint exhaust manifold, the cat comin' off, got my fuel pressure up already, inletmanifold will get flowed,hopefully before the next year, new cold-air airfilter. Well, some tuner companies promise a 20 bhp increase for a ADX with only a camshaft, airfilter and chiptuning. I guess I can get that too easily, considering the 'total' of what I'm planning to do, but I'll see, I'll wil get it dyno-tested after all this

[helios1]

Hey Jarno, youve got a 1.3 right? Ive got one, its engine code is ADX. How much you hoping to get out of ur engine?

pfouh, god question there m8, well, let's see, got a camshaft from a Polo GT with enginecode 3F ready, gonna get a supersprint exhaust manifold, the cat comin' off, got my fuel pressure up already, inletmanifold will get flowed,hopefully before the next year, new cold-air airfilter. Well, some tuner companies promise a 20 bhp increase for a ADX with only a camshaft, airfilter and chiptuning. I guess I can get that too easily, considering the 'total' of what I'm planning to do, but I'll see, I'll wil get it dyno-tested after all this

Ah that sounds pretty savage, how much you spent so far then? So i guess the ADX engine is pretty tunable then?

[JarnoVWPolo6N]

So i guess the ADX engine is pretty tunable then?

Calculate it this way, take the amount of BHP each 6N engine has, and divide it by it's amount of litres, then you'll get the BHP per litre:

75/1,6=46.875
60/1,4=42.85714286
55/1,3=42.30769231
45/1,0=45

and voila, the 1300 (ADX) engine has the least BHP per litre, and the reason for this is the very 'weak' camshaft (it has a 188 degrees cam the weakest in the Polo family for as far as I know), so there's a lot to gain just in the camshaft (for comparison, the cam I've got, from a Polo GT, has 219 degrees, which is almost 16,5% more, so theoretically I should gain about 16%, and if you'de get a Schrick with 268 degres, you'll gain a lot more )

Ah that sounds pretty savage, how much you spent so far then?

So far I haven't spent that much, the airfilter costed me about 100 euro, the cam costed me 80 euro (second hand from German Ebay ), flowing the inletmanifold will cost me 50 euro's (yes, I've got a 'guy' for this one), it's just the exhausmanifold and de-cat pipe which will be the 'pricy objects', but I'm looking for more bargains in Germany

[helios1]

so there's a lot to gain just in the camshaft (for comparison, the cam I've got, from a Polo GT, has 219 degrees, which is almost 16,5% more, so theoretically I should gain about 16%, and if you'de get a Schrick with 268 degres, you'll gain a lot more )

Wow sounds good, so if i just got a GT cam then theoretically I could get 63.8bhp? How does that effect economy?
What mods have you done to your exhaust system?

[JarnoVWPolo6N]

Wow sounds good, so if i just got a GT cam then theoretically I could get 63.8bhp? How does that effect economy?
What mods have you done to your exhaust system?

First, make sure it's the cam for a GT with enginecode 3F, or else it won't be of any use, only the 3F cam has 219 degrees, and is therefor the 'wildest' cam made by VW itself.
And yes, theoretically you'll gain a lot, but due to losses of power in other parts of your engine just a cam switch will generate less gain than the theory, added other tuner-parts will keep adding to the gain and get full 'advantage' from your tuner-parts (for instance, just an air-filter won't give you more power, but air-filter combined with cam and exhaustmanifold wll really do the trick)

And so far I only have an oversized absorption backbox, so it's got bigger piping and absorption dampening (both good for more torque, but like I said before, just this backbox doesn't do anything noticeble by itself, it's the combination of all the stuff I'm planning to do which will be ...... fun )

[david burton]

what cam(s) does the 16v engine have? no-ones ever really said much about the internals of the 16v

[JarnoVWPolo6N]

what cam(s) does the 16v engine have? no-ones ever really said much about the internals of the 16v

Not quit sure really, don't know the exact degrees, but I do know that a 1400 16v 100BHP engine has 'better' cams than the 75 BHP version, straight swap for more power it is but since a 16v already has multipoint injection and a magneti marelli ignition system, it won't give any trouble to get a pair of 276 degree cams from Schrick or Crane or SLS Motorsport, by which I mean it won't f**k up the stationairy of your car (monopoint will probably get trouble with any cam above 268 degrees, m8 of mine drove a 3000 rpm stationairy engine after installing a 276 degree Schrick cam in his 1.3 monopoint injection Polo sounded like crap at stoplights )

[helios1]

First, make sure it's the cam for a GT with enginecode 3F, or else it won't be of any use, only the 3F cam has 219 degrees, and is therefor the 'wildest' cam made by VW itself.
And yes, theoretically you'll gain a lot, but due to losses of power in other parts of your engine just a cam switch will generate less gain than the theory, added other tuner-parts will keep adding to the gain and get full 'advantage' from your tuner-parts (for instance, just an air-filter won't give you more power, but air-filter combined with cam and exhaustmanifold wll really do the trick)

So what kind of power you expecting to get after changing cams/exhaust/filter/chipped? Would it be enough to scare a 16v?

[david burton]

depends on whether you lose low-down torque. If you kept the low down torque you could catch a 16v unawares quite easily.

[helios1]

depends on whether you lose low-down torque. If you kept the low down torque you could catch a 16v unawares quite easily.

So does the valver have all its power up high in the rev range?
How come you lose tourqe with more valves? Same thing happened with the 16V mk2 gti, didnt it?