# differences between ABA + AEG, AVH, or AZG?



## CARBracer (Apr 25, 2005)

what changed in 1999.5 with the 2.0 8v??? if I could get a low-milage 2.0 8v shortblock (AVH), would everything else swap from my beat ABA???


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## vasillalov (Nov 5, 2003)

*Re: differences between ABA + AEG, AVH, or AZG? (CARBracer)*

The most important difference between the ABA and the MK4 2.0 engines is the ignition hardware, the ECU mappings (completely different software), the intake manifold, the exhaust manifold and other miscellaneous hoses, plumbings and stuff..
The ABA uses a distributor while the AEG+ are using a coilpack. Also, the AEG is the last 2.0 engine with throtle cable. The rest of them have the drive-by-wire system.
AVH will be harder to fit because it has the drive-by-wire system. You will need new engine harness, ECU, drive-by-wire pedal and other junk. Most probably the whole digital cluster as well! 
If you get the whole package then yeah, you should be able to do the swap. If you are just getting the block, then you are in for some extra expenses and surprises!


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## vasillalov (Nov 5, 2003)

*Re: differences between ABA + AEG, AVH, or AZG? (CARBracer)*


_Quote, originally posted by *CARBracer* »_what changed in *1999.5* with the 2.0 8v??? i

Sorry for being so tight about it... The AEG was first introduced in 1998 when the New Beetle was released!


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## CARBracer (Apr 25, 2005)

thanks a bunch, that should save me some troulbe!


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## CARBracer (Apr 25, 2005)

out of curiousity, can drive-by-wire be converted?


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## vasillalov (Nov 5, 2003)

*Re: (CARBracer)*


_Quote, originally posted by *CARBracer* »_out of curiousity, can drive-by-wire be converted?

Yes. It has been done before. It is expensive. I have seen engines that were initially drive-by-wire being converted to throtle cable. I have never seen the other way around. I think it is doable, but it will be expensive!
Another important thing is to know that the actual main chip in the ECU box is soldered to the circuitboard in the MK4 and it is socketed (removavble) in the MK3.


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## gltuner (Oct 7, 2004)

Correct me if I am wrong, but don't the mkIV's have a short rod/crank ratio compared to the mkIII's? Isn't that why ABA's put out good/decent torque numbers out of the box while having sh*ty hardware (i.e. manifolds)?


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## digitalhippie (Apr 21, 2004)

*Re: (gltuner)*


_Quote, originally posted by *gltuner* »_Correct me if I am wrong, but don't the mkIV's have a short rod/crank ratio compared to the mkIII's?


Yes. This is why stroking an AEG engine is worthless...


_Modified by digitalhippie at 2:57 PM 5-4-2005_


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## 7thGear (Sep 20, 2002)

*Re: (gltuner)*


_Quote, originally posted by *gltuner* »_Correct me if I am wrong, but don't the mkIV's have a short rod/crank ratio compared to the mkIII's? Isn't that why ABA's put out good/decent torque numbers out of the box while having sh*ty hardware (i.e. manifolds)?

a smaller R/S ratio, all else being equal, will result in greater torque and less revability.


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## vasillalov (Nov 5, 2003)

*Re: (gltuner)*


_Quote, originally posted by *gltuner* »_Correct me if I am wrong, but don't the mkIV's have a short rod/crank ratio compared to the mkIII's? Isn't that why ABA's put out good/decent torque numbers out of the box while having sh*ty hardware (i.e. manifolds)?

You are wrong. Here is the data:
*ABA*:
Bore Diameter: 82.5 mm (3.25 in.)
Stroke: 92.8 mm (3.65 in.)
Compresion Ratio: 10:1
Horsepower: 115 @ 5,400 rpm
Torque: 122 ft-lb @ 3,200 rpm
*AEG, AVH, AZG*:
Bore diameter: 82.5 mm (3.25 in.)
Stroke: 92.8 mm (3.65 in.)
Compression Ratio: 10:1
Horsepower: 115 @ 5,200 rpm
Torque: 122 ft-lb @ 2,600 rpm
Basically the biggest difference comes in the power curves. The AEG+ engines give more torque and horsepower at the lower rpms. Mostly this is due to different camshaft profiles and the individual intake manifold runners compared to plenum in (MK3).
Whoever here sais that the MK4 engine have less power are simply crazy. All 2.0 engines are rated the same. The MK3's feel a little more alive because the car is lighter and there is no dogbone mount which means less engine rocking, i.e. more direct power to the wheels!
As a matter of fact, there is one engine code in the MK4 that was rated for 120 hp! It was only made in very limited quantities.


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## vasillalov (Nov 5, 2003)

*Re: (gltuner)*


_Quote, originally posted by *gltuner* »_ Isn't that why ABA's put out good/decent torque numbers out of the box while having sh*ty hardware (i.e. manifolds)?

Same torque and hp specs as the MK4 engines. The torque and hp actually comes LATER in the rpm range due to the different manifolds and the camshaft profiles!


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## gltuner (Oct 7, 2004)

Thanks for the correction. I was going under the assumption that if everything was the same, the ABA's came out on top. From what I have read from Pagano's post on the intake manifold swap, it appeared to produce more power and torque overall, not just down low. Also, doesn't the mkIV block use a slightly more "aggressive" cam than the ABA block as well? Then include the fact that the exhaust manifold flows better as well. All this seems to add up in my head that if the ABA block had the mkIV intake/exhuast manifolds, and equivelant cam shaft profile, the ABA's will produce slightly more power and torque, even down low. Just my thoughts on it, thats all. Thanks for the correction vasillalov


_Modified by gltuner at 11:54 AM 5-4-2005_


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## digitalhippie (Apr 21, 2004)

*Re: (vasillalov)*


_Quote, originally posted by *vasillalov* »_You are wrong. Here is the data:


No, you are wrong. Didn't look at the rod length, did you?
He asked about the rod/stroke ratio... not just the stroke and bore.


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## digitalhippie (Apr 21, 2004)

*Re: (gltuner)*


_Quote, originally posted by *gltuner* »_Thanks for the correction vasillalov


Ahh, no, ROD LENGTH IS DIFFERENT.
I don't have the numbers right at hand... but the ABA is around 170ish and the AEG is about 140.


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## vasillalov (Nov 5, 2003)

*Re: (digitalhippie)*


_Quote, originally posted by *digitalhippie* »_No, you are wrong. Didn't look at the rod length, did you?
He asked about the rod/stroke ratio... not just the stroke and bore.

I noticed that as well! My apologies.
Here is the deal about the torque curves: The MK4 intake manifold is longer and has individual runners. The longer the intake manifold runners, the earlier the torque comes. The shorter the runners the later the torque comes. This reminds of the V6 Passat B5 engines, not the VR6 engines! They have variable lenght intake manifolds. They use the longer path of the manifold at low rpms and when the engine revs past 3K rpms, the shorter path in the manifold is used. This way you have plenty of torque around the rpm range to pull that heavy car off the line and keep it going!


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## vasillalov (Nov 5, 2003)

*Re: (digitalhippie)*


_Quote, originally posted by *digitalhippie* »_Ahh, no, ROD LENGTH IS DIFFERENT.
I don't have the numbers right at hand... but the ABA is around 170ish and the AEG is about 140.

My apologies, I noticed that too. I did not mean to jump on anybody here. I am here for a healthy discussion, not to argue!


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## 7thGear (Sep 20, 2002)

*Re: (vasillalov)*

why wont anyone listen to me... lol
the R/S has a significant impact on an engines ability to generate torque, and also where it generates it. The camshaft would have greater impact on the powerband more than anything... from what i gather anyway.
as in to say, that the greatest difference in the two engines (aside from head design) are the rod/stroke lengths, camshafts and all that other good stuff is secondary.

also something to pick your nose at
http://www.randdmotorsports.co...l.jpg
honda s2000 stock pull... notice the torque curve... remeber this sucker is also a 2.0 liter, its also oversquared (i htink) and has an R/S of 1.9











_Modified by 7thGear at 12:04 PM 5-4-2005_


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## gltuner (Oct 7, 2004)

As much as that is a very flat curve, I would think that V-tech had something to do with it, so comparing that to our 2.0's is like comparing two different things together (apples and oranges). Does anyone have baseline dyno's of both the ABA block (bone stock) and one of the mkIV's? That would be a really good comparison.
Also, I know someone has swapped out the parts (i.e. manifolds, possibly cams), but has anyone dynoed with those parts? I'd be willing to put on all my stock parts and get a side by side comapro with anyone who has a mkIV all stock. Only problem is I am an auto, so the curve will have to start at about 3k or more. Perhaps I should change my tranny out now










_Modified by gltuner at 12:18 PM 5-4-2005_


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## 7thGear (Sep 20, 2002)

*Re: (gltuner)*

No see, what i was trying to get at is in reference to torque, which i think this thread is going into.
and torque is ultimatly defined by the size of the engine and its contrcution,
the s2000 has a torque curve very similar to that of a slightly moded 2.0... in reality becauze they are both 2 liters.
anyway i had somethign to say.. and now i lost my thought, ahh well.


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## punisher89 (Oct 11, 2002)

*Re: (7thGear)*

Found this it was part of EC's 2.0 litre tuning guide, lots of tasty information in that article. This little blurb was about how hard or easy it would be to swap an AEG to an older car... short end, its damn near impossible.

_Quote, originally posted by *European Car Magazine Fe. '03* »_
_The introduction of the latest batch of VWs, the mk4 chassis cars brought with it a new 2.0 engine. The AEG-code motor, rated at the same 115hp is also a cross flow and has a large number of family resemblences to preceding engines...
The AEG is not a tall block, dropping back to a 220mm like the earlier block (mk2) ... Bore spacing, head bolt pattern and all that stuff is the same but that's about where the similarities end.
The tall block cross flow motor was transitional, as in, a 95 Cabrio (or even later) motor would bolt into a '78 Rabbit. No such luck with the AEG motor. There are no provisions for a side mount-in fact there are no provisions for the mk1/mk2 motor mounts at all. There is no intermediate shaft and thus no distributor- and no place for one. The mk4 cars all have a coil pack ignition.
The oil pump is built into the front of the engine, audi style. because of that the AEG crank is not interchangeable with the previous motors. The snout, bolt and pulley are all different. Its a heavy cast crank, so serious, high revving performance mods are probably not a good idea. The water pump is all in the block and there is a different style of oil pan the cylinder head bolts are 10mm rather than 11mm
The AEG motor does offer a well-designed intake manifold that could possibly be a good choise as an upgrade for mk3 engines, but there would need to be some testing first. The manifold seems to be a more efficient design. The connecting rod is a nice light-weight 144mm forged piece. it is rifle drilled and makes a good upgrade for a 1.8 litre engine.
As we've come to expect from VW this motor is probably better in any number of ways for its intended use. It isn't a better motor for hot rodding than many that came before it... _


That should answer the question posted at the top of this thread.


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## gltuner (Oct 7, 2004)

*Re: (punisher89)*

Nice one http://****************.com/smile/emthup.gif
On another note, does anyone know if the camshaft from the mkIV motor will swap into the mkIII? From the looks of the above article, if it requires a certain head design, it would be practically impossible.


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## punisher89 (Oct 11, 2002)

*Re: (gltuner)*


_Quote, originally posted by *gltuner* »_Nice one http://****************.com/smile/emthup.gif
On another note, does anyone know if the camshaft from the mkIV motor will swap into the mkIII? From the looks of the above article, if it requires a certain head design, it would be practically impossible.

Yeah, it should. THe cranks are different but the cams aren't. In fact the heads are almost identical.


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## gltuner (Oct 7, 2004)

good news, sounds like I maybe needing to make some purchases in the near future then. I really wanna see the curve difference between the ABA block and mkIV blocks, and see what happens with mkIV parts on the ABA block. I just gotta get off my a$$ to a dyno to get a good baseline.


_Modified by gltuner at 1:09 PM 5-4-2005_


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## BlownGTT (May 14, 2004)

*Re: (gltuner)*

So looks like is not worth changing a 1.71 rod radio like in the ABA & ABF for a 1.5~ ratio in the AEZ heads if the engine is prepared for high reving and turbo charged ie if you want to strap a 16v head on it


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## not SoQuick (Jan 8, 2004)

*Re: (punisher89)*

I can tell you that the head castings(casting numbers where same except for date codes) are the pretty much the same as I swapped a 02 head onto my 98.....now I didnt do this by choice but thats another topic all together.only differences I noticed was I had to bore the 2 rear(I think)outer head bolt holes out,no big deal as they are sized the same as the others but just not all the way through.also the oil pressur sender was plugged on the newer head and everything else was a bolt on deal including the cam gear.Now I dont have any before/after dyno runs but I did pick up about 7-8mph on top allmost can get to 125mph


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## 7thGear (Sep 20, 2002)

*Re: (BlownGTT)*


_Quote, originally posted by *BlownGTT* »_So looks like is not worth changing a 1.71 rod radio like in the ABA & ABF for a 1.5~ ratio in the AEZ heads if the engine is prepared for high reving and turbo charged ie if you want to strap a 16v head on it









who says you need an engine hi revving if you want to run turbo
in fact! you would optimatly want to make as much power as you could as low in the rpm as you could
less stress on the engine and greater drivability.


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## BlownGTT (May 14, 2004)

*Re: (7thGear)*

Im refering to the fact that a higher rod ratio will result in lower piston speed, this will result in less wear and also faster reving power, this will allow the engine to rev quicker and higher therefore spooling the turbo quicker and wanting to rev higher than normal where the turbo will produce most of its power once is fully spooled.


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## 7thGear (Sep 20, 2002)

*Re: (BlownGTT)*

again not nesessarily
a _properly mated_ turbo spools amazingly quick, 
in which case you would be better of with a lower RS ratio to take advantage of the bigger torque curve.
but hey, you build your engine your way i'll build mine my.


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## BlownGTT (May 14, 2004)

*Re: (7thGear)*

Yes i agree, the shorter rods will give you more tourqe in the lower revs, tell me one turbo that spooles fast and gives LOADS of power? You would either have to compromise between a smaller turbo spooling fast and being limited in the top end power or a bigger turbo spooling later on the rpm and producing loads of power int eh higher rpm. Now this depends on the application you are using the engine in. For a drag car i would want a higher rod ratio and a higher reving motor being able to put a bigger turbo. Our motors are only 2000cc so the only way to make power in great amounts is higher reving and using big turbos in drag competition. Back in the days they used to run the F1 V6 1.5l twin turbos, how do you think they made 1500hp out of those motors?


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## 7thGear (Sep 20, 2002)

*Re: (BlownGTT)*

http://www.sportcompactcarweb....ilvia/
nuff said,

just because a turbo is big/small doesnt nesessearily mean it will spool fast/slow
again, compressor maps and engine flow charactersitics play a big role in turbo selection
oftentimes the best turbo is one that is custom build of various parts, and not simply an off the shelf unit.
http://****************.com/smile/emthup.gif


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## kimosullivan (Aug 12, 2002)

*Re: differences between ABA + AEG, AVH, or AZG? (CARBracer)*


_Quote, originally posted by *CARBracer* »_what changed in 1999.5 with the 2.0 8v??? if I could get a low-milage 2.0 8v shortblock (AVH), would everything else swap from my beat ABA???

The big difference, IMHO, is that the older ABAs have a taller deck height than the AEGs. The distance from the crankshaft centerline to the headgasket mating surface is longer. I've heard the reason it was shortened up was to fit in under all the plastic bits that adorn the new motors, or perhaps is could be to fit it under the curvey bodywork of the new Beetle. I think an AEG rod to ABA motor swap would be the best way to reduce compression for a turbo setup.


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## t3t4boost (Jan 21, 2014)

*2.0 head cam swap answer*

:wave: 
Hi, I know because I have changed 2 8 valve cams as follows. You can put a abd 11 years 97 98 99 cam in your earlier 8 valve 2.0 and it will run much better. The obd2 cam lift is much bigger. NO mods required. Plug and play. And I can tell you I got a lot more power.


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## rhussjr (Aug 7, 2000)

digitalhippie said:


> <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>gltuner</b> »</i></TD></TR><TR><TD CLASS="quote">Thanks for the correction vasillalov</TD></TR></TABLE><p><br>Ahh, no, ROD LENGTH IS DIFFERENT.<p>I don't have the numbers right at hand... but the ABA is around 170ish and the AEG is about 140.


ABA have 159mm c-t-c length rods (236mm block height) and have an intermediate shaft and distributor and have an external water pump 
AEG, AVH & AVG have 144mm c-t-c length rods (220mm block height) and do not have an intermediate shaft or distributor and have an internal water pump


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## Bdubsyooo (Apr 25, 2014)

So I'm at a loss here, if an aba has the same stoke but different length rods than an aeg.... Does this mean they have the same crank?


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