TDI block for IDI setup

[DieselVanagon]

Could an AHU "short block" be used with a 1.6 non turbo head and injection pump etc.

[TurboJ]

Well... You can if you use IDI pistons. I've seen a couple of engines that have a 1Z/AHU bottom end and AAZ / 1Y head, with AAZ pistons. They fit the TDI con rods exactly, and the TDI rods have the same dimensions as the AAZ rods, while the crank also shares dimensions between AHU/1Z and AAZ.

[55eta]

yup runing a 1z with aaz pistons and abl head and oil pick up /sump

[RabbitJockey]

i wonder how an aaz would run if someone used tdi engine management with a custom chip.  thatd be cool

[boxer246]

The poster specifically asked about 1.6 head with AHU block, and I think Andrew's answer was for that.  And he's right, you can't put a 1.6 mechanical lifter head on a AHU block.  For starters it has only one oil drain hole whereas that AHU block would have the usual later style two drain holes.  Dimension wise, it may be possible to put a later 1.6 hydraulic lifter head on a AHU block....but I havent compared the length of a 1.9 head to a 1.6.  You would then have to run AAZ pistons and I just don't see any possible benefit to doing this.  If you were to go to that trouble, you would be silly not to just use a AAZ 1.9 head as well. 
Basically, an AAZ and AHU block is the same with some small differences.  AAZ rods have weights on the big ends, IIRC the AHU rods do not, AHU crank has position sensor plate on it, AHU pulley end of crank has D shape rather than a keyway, AHU block has hole for crank position sensor, etc.

[55eta]

no mention of mechanical head and perhaps hes not got a aaz head? i was ansewering to the {you can not mix and match idi and tdi blocks and heads} wich you can poviding you use idi pistons

[RabbitJockey]

a hydro head would bolt on an ahu block, and it would probably run.  and it would probably run like ***, the compression ratio would be extremely low.  the compression ratio of a tdi with just a flat head that has no combustion chamber is already 19:1, then with the pre chamber in the 1.6 head youd be getting down into gasoline compression ratios.

[truckinwagen]

a TDI block with AAZ pistons would work with an IDI head.

and as luck would have it, I have a couple sets of AAZ pistons for sale right now!

I would use an AAZ head and not a 1.6, the compression ratio would be excessively high if a 1.6 head were used.

[DieselVanagon]

Thanks, Andrew answered my question since my intention was not to mix match other parts but simply to use a 1.6 head and injection system on a TDI block.

[burn_your_money]

One major difference between the TDI and AAZ block is the lack of the crank position sensor on the AAZ block.

[Powered by Spearco]

Has anyone ever seen those no name brand 1.6 converted to 1.9 engines. I think they were called GEX engines. Reason for asking is that the block is a 1.9 "unknown code" and the head is a 1.6, its stamped on the front.
How did they make theres run with that setup?
Sorry for the hyjack question.

[RabbitJockey]

a TDI block with AAZ pistons would work with an IDI head.

and as luck would have it, I have a couple sets of AAZ pistons for sale right now!

I would use an AAZ head and not a 1.6, the compression ratio would be excessively high if a 1.6 head were used.

i would use an aaz head either way, but a 1.6 head will work, i think the cr ends up as 25:1.  hill folk has an aaz mk2 coupe with a 1.6 head

[Rabbit on Roids]

the CR of a 1.5 is 24.5:1, so is a half a point really gonna make that big of a difference.?

[rabbitman]

the CR of a 1.5 is 24.5:1, so is a half a point really gonna make that big of a difference.?

The 1.5 is actually 23.5:1 and the 1.6 is 23:1

[Rabbit on Roids]

the CR of a 1.5 is 24.5:1, so is a half a point really gonna make that big of a difference.?

The 1.5 is actually 23.5:1 and the 1.6 is 23:1

oh yea, thats it. i knew the 1.5 was a half point higher tho.