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Engine Specific Info and Questions => TDI Engine -General Info => Topic started by: ShoulderMan on March 09, 2010, 08:35:17 am

Title: Why no 1.6l tdi?
Post by: ShoulderMan on March 09, 2010, 08:35:17 am
Ive serched far and wide, but have not found anyone who has put anything togeather and took a picture of it.
Just lots of talk and speculation.
   Is it the pistons that keep anyone from trying this?   As it seems that everything else is taken care of.  Mdti pump, 1z head, 1.6l block,... so the pistons are the limiting factor?
or is there more to it? 
I hear of pistons pricing from 150-250 each,  which scares people away, but a $1200-2000 mtdi pump seems to be, not so bad.
   I also know that they now have a 1.6l tdi with comon rail, but, im sure its a lot more expensive and harder to come by.

 Thanks
-Ron
Title: Re: Why no 1.6l tdi?
Post by: OM617 on March 09, 2010, 07:43:18 pm
Pistons, rods, crank, block.
Title: Re: Why no 1.6l tdi?
Post by: ryanp on March 10, 2010, 02:07:36 am
the 1.2 tdi pistons are said to fit a 1.6 idi block and rods.
Title: Re: Why no 1.6l tdi?
Post by: ShoulderMan on March 10, 2010, 06:55:39 am
why cant you just make custom pistons to fit the 1.6l block?
 then you can use the rest of the assy.
   Is custom making a diesel piston that much more diffucult than making a gasser?
 
Title: Re: Why no 1.6l tdi?
Post by: 8v-of-fury on March 16, 2010, 06:59:37 pm
I think it would take a quite a skilled machinist to make TDI pistons.. (??)

They have caverns in them, as opposed to the flat top gasser pistons and even divets in a idi piston. I would think this would be more cost then it is worth essentially.. having a 1.6 TDI will have no benefits over a 1.9 except maybe a slightly quicker revving engine, with less torque and power? lol

I dunno, just my view on things lol
Title: Re: Why no 1.6l tdi?
Post by: blackdogvan on March 17, 2010, 09:14:14 am
Seems to me a good way to keep the massive fleet 1.6 diesel's in north america going forever. Since Prothe's pistons are possibly the best quality parts available on his site maybe he can source the 1.2L pistons.? Back when Pete was posting here (well at least under his own name) he was looking at a 1.6 tdi conversion but I never heard if it made it all the way. IF there was a cheap piston available its just about finding a head & I guess a mechanical pump would be the best way to go. With the amount of mtdi pump tribal knowledge out there I can see more & more guys being willing to tear into their pump & install a tdi cam plate.

But like Andrew says, with unobtanium pistons its a bit of a non starter.
Title: Re: Why no 1.6l tdi?
Post by: ShoulderMan on March 17, 2010, 11:25:44 am
Well, Ive done a little homework a year or so ago,
 I had found the 1.2l pistons, the only problem, was that they did not make any that were oversized. so, if your 1.6 needed the next size up piston, good luck. they were also around 150-250 each.

 The main goal would be for the mpg. right now i can get 55mpg out of my 300K mile block, and that was with the crappy exhaust manifold and 1" pipe out the back. 
I now have a 3" out the back with the better exhaust casting from a later block, just waiting to have to refuel again to compare.

 And the fact that I have already invested lots into the block and rods. the only thig I need is the oversized pistons to make this work.

Ive seen and read Prothes' site and posts,  I would not mine getting the door handle latches, and some cosmetic pecies. I prefer overkill on engine conponets, like 2 OT battery cables  ;D

I dont know if it would work or fail early, but what about machining the tdi pistons to fit in the idi hole?   then chill harden them and coat them or something?
Title: Re: Why no 1.6l tdi?
Post by: JRD on June 15, 2010, 04:20:41 am
Hy,

I'm comming from French forum, so keep gently with my english!  ;D ;)


I've got the same idea from long time!
I've look at information from different vw engine to know the better pat to use in this project.

Link to the french topic: http://www.vwdiesel.net/forum/index.php?topic=25040.0 (http://www.vwdiesel.net/forum/index.php?topic=25040.0)

My idea is to make a "downsize" Mtdi engine to optimize comsuption and keep power and torque of a standard 1.6TD engine (80hp)
This engine will be used in a VW caddy, my daily car.

The parts I want to use:
- 1.6TD engine RA (just for the block, crankshaft and connecting-rod)
- Engine head from 1Z engine
- Pistons from 1.2L TDI engine (if it's ok for the block!) The other solutions consist to use 1Z pistons and modified the bore of the block. But the capacity growed up to 1715cc...

To optimize this engine, I've fixed a Garrett VNT15 to increase torque at lower RPM.
The Waste-gate have been modified to work without electronic control.


Is the pistons from 1.2L TDI engine realy ok to fit in 1.6TD engine block?

What are the modification to do to the fuel pump?
I've thinking about camplate and high pressure head from TDI engine, but what about the other parts? (I don't really know about optimisation of a fuel injection pump...  :-[)
Title: Re: Why no 1.6l tdi?
Post by: ChopSauce on June 15, 2010, 10:18:41 am
Hi!

Is the pistons from 1.2L TDI engine realy ok to fit in 1.6TD engine block?
The 1.2L TDI pistons are a direct bolt-in swap [...]  It just seems to me like more bang for buck considering how available the 1.9TDI parts and engines are.

An answer to your question was already there. The advice sounds much like the ones you got in the french section. Just build your pump like any mTDI one and everything should be fine - I guess :) Just read on.

One more comment : if you really want to optimise consumption, then you definitely need an eTDI!
Title: Re: Why no 1.6l tdi?
Post by: ShoulderMan on June 21, 2010, 05:03:04 pm
unfortunately,  I have found out why there are no "on the road" 1.6l tdi's
 
 we can not use the 1.2l pistons from the 1.2l block because of how different everything is.  the connections at the Rod end and the Piston connection are trapazoidal.
 
 end of rod connection looks like  / \   instead of normal  ||     they say the extra material at the piston connection allows for a more robust design and can take more beating.  

 the other end of the spectrum is,  yes you can have forged pistons made, but they dont have a mix of material to take the constant beating and detonation that our high 18:5.1 - 22:5.1 compression ratio engines dish out.   they are OK for Drag Race, but not for putting around town getting good fuel milage.


With out having a 1.2l piston to compair to our 1.6l piston we are just guessing on what we could do.  If we bought one new for around $200 each, and found that it was an exact match and drop in to our block,...
First they only come in 1 flavor, Stock  no over sized pistons avi. if you need a fresh bore, your SOL

Second, even if they would drop in,  they wont bolt up to our connecting rods because of the unique shape at the end of the rod.
so at this point you have a very expensive paper weight.

and Third, if you can get one and pay for it, there is a chance that it just wont work
 
NOW, if someone had access to a good used or new piston, and it does by chance fit and work every which way,  there is the possibility of having the piston blueprinted and adjusted to fit our stock connecting rods, then alls we would need to do is get enough people togeather to buy 10 or 20 sets at I would guess maybe 1000 per set and have the piston re cast to fit our needs.

since a cast piston will take the beating that a forged piston will not.

Title: Re: Why no 1.6l tdi?
Post by: ShoulderMan on June 21, 2010, 05:20:40 pm
(http://i607.photobucket.com/albums/tt157/ShoulderMan78/trap.jpg)
Title: Re: Why no 1.6l tdi?
Post by: JRD on July 07, 2010, 01:32:00 am
So is it possible to use the 1.2L tdi connecting rod?

What is the length and the head diameter (to fit on the crankshaft) of these connecting rod?

I've found your topic about rod length
http://www.vwdiesel.net/forum/index.php?topic=24920.0 (http://www.vwdiesel.net/forum/index.php?topic=24920.0)

Do you have more information now?
Title: Re: Why no 1.6l tdi?
Post by: TDIMeister on July 07, 2010, 05:52:02 am
http://forums.tdiclub.com/showpost.php?p=3038171&postcount=51 (http://forums.tdiclub.com/showpost.php?p=3038171&postcount=51)
Title: Re: Why no 1.6l tdi?
Post by: TDIMeister on July 07, 2010, 05:57:12 am
I suggest a different track.  Start with a 1.9 TDI long block and install a short-stroke crank.  The 1.6 IDI has an 80mm stroke, which yields 1588 cc.  All else being equal, compression ratio will drop from 19.5 to 16.5.  The pistons, block and crank remain VW parts bin components.  Only the rods need to be custom.  Much cheaper (and available) than pistons.
Title: Re: Why no 1.6l tdi?
Post by: ShoulderMan on July 10, 2010, 09:34:32 am
Before that, I had even thought of going down the newer road and using the new 2010 1.6l common rail engine pistons, but it seems as if they are also of the 1.9l specs, with, like you said, a 1.9l bore and a shorter stroke.  So, out of all of this, seems the new generation is going with the larger piston bore as well.

 In order to keep the shorter stroke, will I beable to use the 1.6l crank?  its just a drop in part?

Another Question I had, Can I use the rods from a 1.6l Block, and just Mill the Deck of the 1.9l block? to get an acceptable c/r?

and are all 1.9l blocks interchangable with the 1.9l AAZ head? from 2000-2010?
Title: Re: Why no 1.6l tdi?
Post by: Rabbit on Roids on July 10, 2010, 09:51:36 am
you gotta mill 16mm off an aaz deck to get it to where you want it to be. unless you use some sort of longer rods.

the AAZ is 16mm taller than the 1.6 block.
Title: Re: Why no 1.6l tdi?
Post by: oldskool rich on July 19, 2010, 02:10:15 pm
sumone was telling me that a 1.9 is better because its square, ie the stroke is the same as the bore
is that true?

in my mind it makes sence to have a 1.6 crank in a 2.0 block with PD 8v pistons and ALH head u just need to chop the block down and get custom rods

infact im doing just that in my caddy but with stock crank hoping for sum gud power
Title: Re: Why no 1.6l tdi?
Post by: MJF on July 19, 2010, 04:04:18 pm
1,9 is even nowhere near square. Bore 79,5mm and stroke 95,5mm.
Title: Re: Why no 1.6l tdi?
Post by: JRD on October 04, 2011, 06:21:15 am
I'm always thinking about a 1.6L TDIm

VW put a 1.6L Common rail TDI engine (called CAYA or CAYB) in the new polo.
Most of the caracteristic of this new engine is similar to 1.9L TDI engine.
I think the 1.6L TDI engine is made from 1.9L engine block with special cranshaft and special conrod.

If it's right, maybe it's possible to do a 1.6L TDim by using the crankshaft and the conrod from a 1.6L CR TDI engine (CAYA or CAYB) in a 1.9L TDI engine (1Z or AFN)!! ;D

Problem: it's hard to find the polo in a scrap yard...  :-\
Title: Re: Why no 1.6l tdi?
Post by: RabbitJockey on October 04, 2011, 09:24:33 am
you could make a 1.7tdi easily with a 1.6 crank in a tdi block with tdi rods and pistons, you would just need to deck the block down about 9.1mm to get the proper piston height, but this is assuming there is enough webbing in the tdi block.
Title: Re: Why no 1.6l tdi?
Post by: RabbitJockey on October 04, 2011, 09:25:59 am
how ever due to the nature of how diesel air fuel ratios work, i don't see there being much gain by doing this, maybe slightly better revability due to the short stroke and better rod angles.  but mpg i imagine would remain the same.
Title: Re: Why no 1.6l tdi?
Post by: JRD on October 04, 2011, 01:16:14 pm
The fuel consumption goes down with the engine capacity. ;)

The problem of this engine is caused by the bore who is higher than the stroke, this configuration is normally made for petrol engine to improve RPM...
Title: Re: Why no 1.6l tdi?
Post by: JRD on January 12, 2012, 12:45:56 am
After lot of research, I hope I've found a solution to make a 1.6L TDI engine.


- crankcase from a 1.6L TD engine
- cranshaft, connecting-rod from a 1.5L D engine
- piston from a 2.5L V6 TDI engine
- cylinder head from 1.9L TDI engine

The result:
- cubic capacity of 1541cm3 (bore: 78.3mm, stroke: 80mm)
- compression ratio 16,1:1



Modification to do.
- Change the crankcase bore from 76.5 to 78.3mm to accept the 2.5L V6 TDI pistons
- Change the diamètre of the conrod from 22mm to 26mm to accept the piston axle
- Modificate the head to improve compression ratio from 16,1:1 to 19,5:1
Title: Re: Why no 1.6l tdi?
Post by: MJF on January 12, 2012, 12:59:23 am
With quick calculating, V6 piston would stick 3mm higher from block than 1,5 piston.
Title: Re: Why no 1.6l tdi?
Post by: JRD on January 12, 2012, 01:34:28 am
It's possible.


To ensure it, I need to know exactly the heigt and the axle diameter of the 2.5L V6 TDI piston
Title: Re: Why no 1.6l tdi?
Post by: MJF on January 12, 2012, 03:29:55 am
http://www.motorenteile.mahle.com/eLIZA/mahle/query/engine/byParams

Good source for dimensions.
Title: Re: Why no 1.6l tdi?
Post by: JRD on January 12, 2012, 03:50:35 am
Thanks a lot!
Title: Re: Why no 1.6l tdi?
Post by: R.O.R-2.0 on January 12, 2012, 06:50:12 am
After lot of research, I hope I've found a solution to make a 1.6L TDI engine.


- crankcase from a 1.6L TD engine
- cranshaft, connecting-rod from a 1.5L D engine
- piston from a 2.5L V6 TDI engine
- cylinder head from 1.9L TDI engine

The result:
- cubic capacity of 1541cm3 (bore: 78.3mm, stroke: 80mm)
- compression ratio 16,1:1



Modification to do.
- Change the crankcase bore from 76.5 to 78.3mm to accept the 2.5L V6 TDI pistons
- Change the diamètre of the conrod from 22mm to 26mm to accept the piston axle
- Modificate the head to improve compression ratio from 16,1:1 to 19,5:1


sorry, but your not going to bore a 1.5 rod small end out to have enough meat left to have a bushing in the end, and hold a 26mm wrist pin..

time for another solution.
Title: Re: Why no 1.6l tdi?
Post by: JRD on January 12, 2012, 12:04:12 pm
 :( Same player shoot again... ::) ;D
Title: Re: Why no 1.6l tdi?
Post by: JRD on January 12, 2012, 11:08:05 pm
http://www.motorenteile.mahle.com/eLIZA/mahle/query/engine/byParams

Good source for dimensions.

They don't have informations from 1.2L 3 cylinder TDI engine.
I tried the kolbenschmidt site but without success.

Do you know who manufactured this pistons?
Title: Re: Why no 1.6l tdi?
Post by: MJF on January 13, 2012, 02:36:06 am
Maybe Nüral? 1,2 has 76,5mm bore and 24mm piston pin, that info can be found from Etka. That's all I know of that engine.
Title: Re: Why no 1.6l tdi?
Post by: mdonau on January 13, 2012, 03:31:48 am
hi,

I am currently building a 1,7l TDI using a 1,7 SDI (engine code "AKU")

The crankshaft, conrods and pistons fit perfecly into every 1,9l DI block.
The plan is to use this engine with stock 1Z/AHU components in my VW T3 Syncro

greets, michael
Title: Re: Why no 1.6l tdi?
Post by: R.O.R-2.0 on January 13, 2012, 11:20:37 am
hi,

I am currently building a 1,7l TDI using a 1,7 SDI (engine code "AKU")

The crankshaft, conrods and pistons fit perfecly into every 1,9l DI block.
The plan is to use this engine with stock 1Z/AHU components in my VW T3 Syncro

greets, michael

a 1.7 SDI is basically a TDI already, just without a turbo..
Title: Re: Why no 1.6l tdi?
Post by: theman53 on January 13, 2012, 04:39:34 pm
Maybe Nüral? 1,2 has 76,5mm bore and 24mm piston pin, that info can be found from Etka. That's all I know of that engine.
Need more info on this :D . I really would like to do a 1.6 TDI.
Title: Re: Why no 1.6l tdi?
Post by: MJF on January 13, 2012, 05:23:54 pm
http://www.ebay.de/itm/VW-LUPO-3L-KOLBEN-KOLBE-1-2-TDI-ANY-AYZ-AUDI-A2-/320627118719?pt=DE_Autoteile&hash=item4aa6dd927f#ht_13368wt_1265

Someone should buy and measure those...
Title: Re: Why no 1.6l tdi?
Post by: theman53 on January 13, 2012, 05:40:00 pm
Find me a 4th and I will.
Title: Re: Why no 1.6l tdi?
Post by: JRD on January 29, 2012, 10:55:24 pm
Alcan manufactured the 1.2L TDi pistons.
But I've not find anything on his site to know more about this pistons...  :(
Title: Re: Why no 1.6l tdi?
Post by: Pat Dolan on February 11, 2012, 01:54:11 pm
I do understand why someone might want a 1.6TDI to keep the old 1.6TD block fleet in heads into the future, but, honestly, if one is looking for economical engine - just buy a 1.2l or 1.4TDI and bolt it in.  The friction from 3 pistons will trump that from 4 any day. 

If one is fixated on 4 cylinders, then just start with a 1Z or AHU and put 20% taller gearing in place.  Now you have the same swept volume at the same road speed as the previously geared 1.6 4 banger - and you don't have to diddle at all with the engine.  Friction wise, the reduction in engine speed should proportionally offset the extra ring-to-wall drag from displacement.

The bonus, of course, is that you can just drop a gear and have all of that 1.9 litre sweetness when you need it - at no extra cost.

Some times, the pragmatic solution is just hiding well behind the obvious.
Title: Re: Why no 1.6l tdi?
Post by: theman53 on March 15, 2012, 04:57:40 pm
I still am kicking this idea around. I may just buy those pistons and start measuring while the 1.6 is on the stand.
Title: Re: Why no 1.6l tdi?
Post by: JRD on March 27, 2012, 04:02:19 am
I do understand why someone might want a 1.6TDI to keep the old 1.6TD block fleet in heads into the future, but, honestly, if one is looking for economical engine - just buy a 1.2l or 1.4TDI and bolt it in.  The friction from 3 pistons will trump that from 4 any day. 

If one is fixated on 4 cylinders, then just start with a 1Z or AHU and put 20% taller gearing in place.  Now you have the same swept volume at the same road speed as the previously geared 1.6 4 banger - and you don't have to diddle at all with the engine.  Friction wise, the reduction in engine speed should proportionally offset the extra ring-to-wall drag from displacement.

The bonus, of course, is that you can just drop a gear and have all of that 1.9 litre sweetness when you need it - at no extra cost.

Some times, the pragmatic solution is just hiding well behind the obvious.

I'm OK with you.
But, for me, building a 1,6L TDI is more difficult and interesting than swap a 1,4L TDI!