i just got lucky!!! =)
01-13-2009, 11:42 PM
#1
AudiWorld Super User
Thread Starter
i just got lucky!!! =)
i just scored a set of brand new factory heads from Audi for a steal of a price. they are the last two in the USA warehouses. ill post pictures when they get here, which should be Friday...
I was tempted to by the last 12v V6 motor, but i cant ditch out 1300 at the moment :-(
sorry, but i had to brag about this one :-)
I was tempted to by the last 12v V6 motor, but i cant ditch out 1300 at the moment :-(
sorry, but i had to brag about this one :-)
01-14-2009, 10:46 AM
#5
AudiWorld Senior Member
Are the heads for the Euro 2.6 any different from the 2.8 ? Any other...
<center><img src="http://lh6.ggpht.com/_fUU9IuyXLAQ/RxDMf53yrbI/AAAAAAAAAFw/q4U8V2tJkFA/s640/Audi_A4_Motorraum_%20001.jpg"></center><p>
...differences between the 2.8 AAH/AFC/ACK and the 2.6 ABC/ACZ? Certainly the intake manifold looks different (photo above; still a 12v?). Are the exhaust manifolds, I/M switch-over point, ECM injector cut-off rpm, etc. any different?
Has anyone here driven both sizes?
Was the reduction in compression of the late AFC (12/1994) vs AAH/early AFC done by changing the pistons or heads? Thanks.
...differences between the 2.8 AAH/AFC/ACK and the 2.6 ABC/ACZ? Certainly the intake manifold looks different (photo above; still a 12v?). Are the exhaust manifolds, I/M switch-over point, ECM injector cut-off rpm, etc. any different?
Has anyone here driven both sizes?
Was the reduction in compression of the late AFC (12/1994) vs AAH/early AFC done by changing the pistons or heads? Thanks.
01-15-2009, 04:39 AM
#6
New Member
Join Date: Jul 2008
Location: SWEDEN
Posts: 12
Likes: 0
Received 0 Likes
on
0 Posts
Re: Are the heads for the Euro 2.6 any different from the 2.8 ? Further...
Living in europe I can answer: The ABC engine has exactly the same block and heads as AAH. The difference is in the crank and pistons (longer throw). The intake on the 2.6 is a fixed intake made of plastic and here is the main difference between 2.6 and 2.8 and this makes for 75% of the power gains. (150 vs 174). Eurospec 2.6 has no EGR and HELLA ECU without MAF, eurospec 2.8 has no EGR and Hitatchi ECU and MAF. Everything else is the same between ABC and AAH.
01-15-2009, 08:28 AM
#7
AudiWorld Senior Member
Interesting. As the compression ratio is a little lower on the 2.6, I'm wondering...
...if the pistons might possibly even be the same as the 2.8's?
Will your valves still hit the pistons if the 2.6 timing belt brakes or is installed improperly?
Sorry, I'm not entirely clear as to what you are you suggesting, are you saying that "75% of the power gains" (the 2.8 over the 2.6) are due, not just to the displacement increase, but to:
a.) the variable length alu. intake manifold over the fixed length plastic one; or
b.) the Hitachi ECU over the Hella one.
Does the Hella ECU use a manifold absolute pressure (MAP) sensor vs a MAF sensor?
Does the plastic manifold get too hot to touch after the car has been driven?
Thanks.
Will your valves still hit the pistons if the 2.6 timing belt brakes or is installed improperly?
Sorry, I'm not entirely clear as to what you are you suggesting, are you saying that "75% of the power gains" (the 2.8 over the 2.6) are due, not just to the displacement increase, but to:
a.) the variable length alu. intake manifold over the fixed length plastic one; or
b.) the Hitachi ECU over the Hella one.
Does the Hella ECU use a manifold absolute pressure (MAP) sensor vs a MAF sensor?
Does the plastic manifold get too hot to touch after the car has been driven?
Thanks.
Trending Topics
01-15-2009, 08:33 AM
#8
New Member
Join Date: Jul 2008
Location: SWEDEN
Posts: 12
Likes: 0
Received 0 Likes
on
0 Posts
Re: Are the heads for the Euro 2.6 any different from the 2.8 ? Further...
Answering some more of your questions:
Exhaust manifolds are the same ABC-AAH.
There is no switch over in the IM on ABC becasue its fixed length.
I have driven both, and the 2.6 (still a 12V) is very different from the 2.8. The 2.6 has the smooth running of a sixcylinder engine but its soooo lame, no low end grunt, no top end power and slightly higher consumption than the 2.6. In europe most cars are equipped with the 2.6 if the car has a V6 in B and C platform
If you add the 2.8 IM to a 2.6 and do some fuelling tweaks you cant feel any difference to a "real" 2.8.
Exhaust manifolds are the same ABC-AAH.
There is no switch over in the IM on ABC becasue its fixed length.
I have driven both, and the 2.6 (still a 12V) is very different from the 2.8. The 2.6 has the smooth running of a sixcylinder engine but its soooo lame, no low end grunt, no top end power and slightly higher consumption than the 2.6. In europe most cars are equipped with the 2.6 if the car has a V6 in B and C platform
If you add the 2.8 IM to a 2.6 and do some fuelling tweaks you cant feel any difference to a "real" 2.8.
01-15-2009, 08:42 AM
#9
New Member
Join Date: Jul 2008
Location: SWEDEN
Posts: 12
Likes: 0
Received 0 Likes
on
0 Posts
Re: Interesting. As the compression ratio is a little lower on the 2.6, I'm wondering...
The pistons are NOT the same due to the extra 173c created by longer stroke the crown of the piston in the 2.8 is lower.
In the 2.6 the valves will hit the pistons if the timing belt is incorrect, no difference there.
a)75% of the extra hp is from the IM and 25% from the 173cc.
b)no, the hella is actuallay better due to not having the restrictive MAF in the way of the airflow. TB are the same as well.
Correct, Hella uses MAP and MAT to calcuclate the load.
The plastic IM is crap, it does not withstand the underhood temeperatures and crack internally and loose pieces of plastic falls into the engine, and yes it get too hot to touch.
In the 2.6 the valves will hit the pistons if the timing belt is incorrect, no difference there.
a)75% of the extra hp is from the IM and 25% from the 173cc.
b)no, the hella is actuallay better due to not having the restrictive MAF in the way of the airflow. TB are the same as well.
Correct, Hella uses MAP and MAT to calcuclate the load.
The plastic IM is crap, it does not withstand the underhood temeperatures and crack internally and loose pieces of plastic falls into the engine, and yes it get too hot to touch.
01-15-2009, 11:01 AM
#10
AudiWorld Senior Member
So 2.6 folks might fancy the alu. manifold for both reliabilty and short path peak power, and...
...2.8 folks can't use the 2.6 pistons because their too tall? However they might employ the Hella ECU. Except the Hella may have no provision to open the intake manifold butterflies (IIRC this signal comes from the ECU?).
The MAF as a point of restriction may not be an issue if you go post-less as some here have done. On the other hand, perhaps a MAP sensor is more reliable than a MAF. I've read that MAF sensors resist cleaning at some point.
What I was wondering was, since the 2.6 peaks at a higher speed for instance, perhaps the Hella ECU's maps are different. Might the Hella be more "sport" oriented (ignoring the I/M issue) if used on a 2.8 (if even possible)?
The MAF as a point of restriction may not be an issue if you go post-less as some here have done. On the other hand, perhaps a MAP sensor is more reliable than a MAF. I've read that MAF sensors resist cleaning at some point.
What I was wondering was, since the 2.6 peaks at a higher speed for instance, perhaps the Hella ECU's maps are different. Might the Hella be more "sport" oriented (ignoring the I/M issue) if used on a 2.8 (if even possible)?