8v DIY Head Porting???

[JarnoVWPolo6N]

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

What u mean by low down torque? torque in lowers rpm's? If so, your correct, but torque come's from the 'speed' with what your fuel/air mixture can reach your cilindres, so by flowin your inletmanifold, and improving air filter and increasing fuel pressure will do the trick, but if you really wanna scare a 16v with your 1.3spi 8v, put on a mpi-system from a AEE, 3F or NZ engine, this will really increase your torque, but is quit hard to uptain (cuz you'll need the appropriate ECU and computer and keys (for the chips that otherwise block your starting)) and will take more work and money then flowin manifold, fuel pressure regulator and improving airfilter, that's why I chose that option, will give less torque then other option, but isn't hard to do, doesn't take long, and money doesn't grow on trees

[helios1]

Whats the difference between mpi and spi?
What is mpi/spi?

Sorry about all the questions, im not too hot on engines

[david burton]

yes I meant the torque at low revs. not sure why you lose it on the 16v - I guess you don't really, it just revs more freely so the peak torque is 4400rpm. but torque and power are related anyway - it's a direct equation between the two.

mpi is multipoint injection - into each cylinder. spi is single point.

[helios1]

mpi is multipoint injection - into each cylinder. spi is single point.

Ahhh! *Duuuh*
So is the AEE engine code just 16v? didnt think any other polo engine had mpi

[bstardchild]

mpi is multipoint injection - into each cylinder. spi is single point.

Ahhh! *Duuuh*
So is the AEE engine code just 16v? didnt think any other polo engine had mpi

1.4 8V AEX is multipoint - I think it's only the early 1.3's that were spi but not 100% sure

[david burton]

it's the 1.6

lots of the egines had MPI IIRC, the 1.0L I had previously had MPI, and the 1.4's do to, I believe

[david burton]

you got there first!

the mk4 FAQ has an engine code guide - some of the early 1.6's and 1.0L had SPI too

[JarnoVWPolo6N]

Well first the MPI/SPI question
for simplicity I'll only name the 6N engine's (non-diesel)

SPI's
1000cc AEV
1300cc ADX
1600cc AEA

MPI's
1000cc (dunno enginecode form my head)
1400cc AEX
1600cc AEE

and all 1400cc 16v's and 1600 16v GTI (yes, there's a 6N GTI version, was only released in germany, about 3.000 sold, had a 1600cc 16v engine like mk 5 GTI's, but had 'only' 120 bhp (5 less then mk5 GTI))

yes I meant the torque at low revs. not sure why you lose it on the 16v - I guess you don't really, it just revs more freely so the peak torque is 4400rpm. but torque and power are related anyway - it's a direct equation between the two.

it's simple why a 8v losses it to a 16v, a 16v engine has 2 valves for inlet, and 2 for outlet/exhaust, so in less time there can go more fuel/air mixture in each cilindre then a 8v can do, so a 16v will have more torque then a 8v. But since not every engine is 'optimal', you can get more torque from a modded 8v then a standard 16v, just make sure your fuel/air micture get's in your cilindres a lot quicker then a 16v can, and your done, well, it's not that simple, but that's the theory again

[HGA05]

I have a 1996 POLO SE which has a 1.4 8v engine (AEX). So far i have a cat back exhaust system. What else can i do to the engine and what is the best thing to do next considering im a student and money doesn't grow on trees. It would be much appreciated if someone could give me some ideas.

[JarnoVWPolo6N]

I have a 1996 POLO SE which has a 1.4 8v engine (AEX). So far i have a cat back exhaust system. What else can i do to the engine and what is the best thing to do next considering im a student and money doesn't grow on trees. It would be much appreciated if someone could give me some ideas.

If you don't feel like spending "much", don't do it. Next step to gain some good enginepower/torque is or the camshaft or the exhaustmanifold. Both can be purchased for around 200/250 euro (sorry, not really into Brittish prices ) And considering you have an AEX-engine (MPI), you can easily go for a 268 or 286 camshaft.
De-catting will also always improve, but isn't road-legal, so make sure to be able to swap back your old catalyst convertor

[HGA05]

Where is the best place to buy a camshaft for the AEX engine and which is the best value for money. Are there any VW cams that will fit this engine that will increase performance. Also what power gains are to be expected from having one of these?