2.0l 16v Engine differences

[barrygti]

Hey guys,

Need help with engine differences, I have heard of 9A and ABF engines, I believe both are 2.0l 16v but what's the difference?

Or what are all the differences.........

I am going to swap to 2l in my Mk1 eventually and need to know what's best(will be turbo in long run also) but I am new to VW scene....

[ausgolfer]

http://www.clubgti.com/forum/showthread.php?t=51&highlight=9a

Different crankshafts and rods and pistons, and debate still rages about which is better.

Main differences are ABF is electronic injection and 9a is KE-jetronic.

And the 9a has much milder cams as stock because it's in a much milderand heavier car.

[h100vw]

I have had both engines, one in a Passat Wagon the other in a MK3 Golf. The ABF is the one to have hands down. A far superior engine, VW quit developing the 9A for a good reason, the ABF was better.

Throttle response is like a MK1 and with a chip it'll do 170bhp or so.

Gavin

[Bora Sport]

My understanding is that the 9A was basically for the American market where torque is king. It had roughly the same horsepower as the KR but heaps more torque lower in the rev range. They also did a torquier version of the KR (1. for America which is known as the PL. It had around 122hp as I recall. I think Dave DOHC has one in his Mk 1 and it goes quite nicely. No doubt there are other variations. I had a 9A in my Mk 2 (converted from a KR). It ran out of puff at about 6500rpm whereas the KR revved to the limiter around 8000rpm.

The 9A was far superior in day to day driving though and for in gear performance the 9A would run away and hide from the KR. My mate put the KR cams into a 9A plus the KR inlet manifold and got an instant 155hp.

I had my Beeza on the dyno yesterday and it ran 91.6 kW at the wheels and it is absolutely stock. My 9A with slightly higher compression than standard and a VSAM on it ran 81 kW on the same type of but different dyno with everthing stock including exhaust.

[Valver.]

These are the main differences:

- ABF has a tall block, 9a has a short
- ABF has 159mm rods and 21mm wrist pins, 9a has 144mm and 20mm pins
- ABF has a 52mm inlet manifold, 9a has a 50mm or 42mm depending on which motor you find and whether or not anyone has tinkered with it
- ABF has a single butterfly throttle body, not a twin
- ABF has 10.5:1 compression, 9a 10.8:1
- ABF has Digifant 3 EFI, 9a has mechanical fuel injection
- ABF has longer valve stems, different combustion chambers and slightly different shaped ports; it also has VR6-style retainers and slightly lighter lifters
- ABF cams have longer lift and duration
- ABF uses a longer timing belt
- ABF uses a serpentine belt setup for the alternator, water pump etc, rather than a V-belt like the other 16vs. It's smoother and quieter basically
- ABF cam cover is different - the two centre mounts are counter sunk into the cover rather than on top
- ABF uses a coilpack for ignition and has a 90deg. angle on the distributor cap
- ABF was sold right up until MY99 in the SEATs, though most of the blocks are stamped 96, so should theoretically have lower mileage

- That's all I can remember off the top of my head, but there are other differences with knock sensors etc

[barrygti]

Ok thanks so much for all that guys, so next question is, does the taller block ABF fit straight in to a Mk1 like a 9a?

Plan is to turbo it, so if the 9a is tourqier then I suppose ABF would be better as turbo will fill in midrange anyway....... just ABF's are hard to find in New Zealand......

[ausgolfer]

Valver is the person to ask, as his mk1 has an ABF in it, I remember reading about a lot of the guys have height issues in the UK back in the day with ABF's in mk1's but there's obvioously ways around it.

[finemk1]

ive found you need a kr sump and oil pump when putting a tall block in a mk1, tends to hangs down a bit, if your car is standard hieght it might be ok.. and like usual u will need all the 16v mounts and what not

[aprr32]

The block is taller at the top not at bottom, that why the exhaust down pipe is longer and bonnets are closer.

[Valver.]

The block is taller at the top not at bottom, that why the exhaust down pipe is longer and bonnets are closer.

Exactly right Whether or not the ABF fits in a Mk1 depends which bonnet you have.

There are three different types:

- The "smoothie hood" as the yanks call it (this has the crease in the front edge and was found on very early Mk1s - i.e. swallow tails)
- The later bonnet with the lip along the front. There are two types and they look the same on the outside, but the shape of the bracing underneath is different. The later one is that which works with the ABF swap. There is 20mm of clearance against the front edge of the inlet manifold in my (now dead) Mk1 - this is the closest point. I bought a brand new bonnet from VW to suit a '91 Mk1 Cab'.

[barrygti]

So if I was going for a new inlet manifold then it's not a problem??

What about gearbox and engine mounts on ABF is it all drop in like 9a is I believe???

[Valver.]

If you're going to run a short runner intake for a turbo set-up then you'll have even less chance of the motor fitting in most cases, because the tightest point is up the front of the engine bay and most of the short runner intakes rake upwards. I bought an EIP one for my new engine and it didn't have a hope in hell of fitting, so I sent it back!

The stock ABF intake actually works quite well with the turbo pipework; it's just a bit difficult to configure the fuel rail and injectors.

[barrygti]

Ok well here is the long and short of it, how much better is the ABF if going turbo? I mean I will be heading for hopefully 250-300bhp MAX so is a 9a capable? I know if staying NA then I would go ABF but boost tends to be a leveller......

Or should I got to the hassle of a ABF, again does it fit my stock Mk1 box and mountings like a 9a?

Thanks for the help!!!!!!!

[evorobin]

Buy a 20V.

[barrygti]

In New Zealand they are hard to come by and I fancy a project not a drop in and run it....... Always preferred idea of 2l 16v in Mk1 anyway........ and have the turbo sorted.......