can i build a NA block to handle a turbo?

[2mAn]

is it even worth it??

i have an extra NA block that id like to build up to handle a turbo. i was curious if there are some good pistons out there that dont need oil squirters to survive? this also means i would probably have to upgrade the rods too, is that right? also how much can i bore the block out to? the block is comin from a 79 rabbit diesel so im guessin it is a 1.5, can i go as big as 1.7 or even 1.8 (which im thinkin would be a +2mm bore at least).

again, is this even worth it?

[tylernt]

http://www.vwdiesel.net/phpBB/viewtopic.php?t=3400&sid=a46a2d9b41122371577a7d8a328b6135

You will need to install an intercooler and keep your temps way, way low. The TD cyl head is of a different alloy and the NA head won't take much heat without warping. To control heat, you might look at getting the combustion chamber, exhaust valves, and exhaust ports thermal coated -- see this thread: http://www.vwdiesel.net/phpBB/viewtopic.php?t=2329&highlight=

If Raceware makes an 11m head stud kit, that will provide a better head-to-block seal with less risk of stripping the bolt threads in the block.

[Kudagra]

Is there actual evidence that the Turbo Aluminum head is a different alloy then the N/A head? I am skeptical of this. I remember when I was messing with Ford 2.3s and there were rumors floating around that those turbo heads were of a different cast iron alloy then the N/A heads. But for somereason they had the same casting numbers :roll:  Now I do know that they used different exhaust valves (like the VWs...sodium filled) because I purchased some of the expensive buggers and Ive cut them open (ever messed with sodium and water? :twisted:  )Same went for the Blocks that rumored to have more nickle content.

 Now all that might be true but Id like to read it somewhere other then some ones post.


As far as I know the safest way to convert a N/A block for turbo use is to drill and install some oil squirters. Ive heard it can be done (what cant really??) and has been done here...but IM not sure of the post.

[tylernt]

Is there actual evidence that the Turbo Aluminum head is a different alloy then the N/A head?

The Bentley says that the turno head is made from a different, sodium-injected alloy. Dunno how authoritative that is, though.

I can tell you the N/A heads warp from overheating really easily, though.   :roll:

[the4ork]

ok so if just looking at the BLOCK....

the only difference between the na and td is that the td has oil squirters?

and does anyone know the rod size on the 1.6?

[tylernt]

ok so if just looking at the BLOCK....

the only difference between the na and td is that the td has oil squirters?

Yes if you are talking about a block that came on a hydraulic lifter car. The solid lifter blocks are missing an oil return but you can work around that by getting creative with the head or head gasket.

The TD pistons have a notch for the oil squirter, but I beleive there have been people that have successfully notched N/A pistons for clearance.

Dunno the rod size, sorry.

[the4ork]

can we use 1.9 pistons? obviously after a bore... and they should have the notch for the squirters...

sorry for the thread jack simon, maybe these are helping you too

[Kudagra]

The Bentley says that the turno head is made from a different, sodium-injected alloy. Dunno how authoritative that is, though.

What page does it say that? I looked through mine and I didnt find that. The only time I saw Sodium mentioned was talking about the sodium filled exhaust valves telling not to cut them open.

[tylernt]

What page does it say that?

Page 4 of the Engine section, under Cylinder Head. It's not describing any procedures, just giving general info.

sodium filled exhaust valves telling not to cut them open.

I'm told that can be great fun... when you cut them open and then drop 'em in a big bucket of water.  :twisted:

[jtanguay]

the crankshaft is different in the turbo models as well.  (although the N/A one might be capable of handling short-term extra load)

[Justin]

you can get away with oil squirters either in the block or rods, my machine shop charged me 40 bucks to drill them into the block. its a 10 degree angle from the main journal to the center of the piston at the top. you can see some pics at my cardomain site

http://www.cardomain.com/ride/2223781/1

I have over 3000 miles on this engine with no issues thus far and absolutely love the turbo with 20 pounds of boost, govenor mod and a little more fueling.

later
Justin

[tylernt]

can we use 1.9 pistons? obviously after a bore... and they should have the notch for the squirters...

Well the Bentley lists a max bore diameter of 77.53mm, up from 76.51mm stock. Not a lot of difference. Of course, I imagine you could go bigger as the factory is usually pretty conservative. Check this out:

http://forums.vwvortex.com/zerothread?id=2292986

He bored out a diesel block to use on a gasser. Says he overbored .110" and used 1.7 gasser pistons. I'm not sure how much further you can push it...

[Justin]

libbybapa,

you could machine a groove in the bearing if you wanted, or a groove behind the bearing would work as well, I am not sure about the what would be required on the rod, I did it off of the main journals behind the bearing shell as you can see in my photos on car domain.

on the note that you dont see how the holes in the rod would get fed, you would have to atleast drill a hole in bearing shell, and possibly a groove as described above to feed it. I am not sure if you would need the groove since the high oil pressures are sufficent in going all the way around the cearing surface. but like i said before you would at least have to drill a hole in the bearing if it was for the rods, unless you machined a groove behind the bearing which would be slick i think but may encourage the bearing to spin and then you have all sorts of problems. so I would do either a grooved bearing and or a hole in the top  part of the bearing that leads to a straight up hole that constantly sprays the underside of the piston.

sorry for the novel of an answer hope that you get it through all of the senseless ramblings.

later
Justin

[Kudagra]

Page 4 of the Engine section, under Cylinder Head. It's not describing any procedures, just giving general info.

How about a page number like 15.4 or 15.32. Or even better...how about a scan. Im not saying you are wrong Id just like to read it with my own eyes.

[tylernt]

Page 4 of the Engine section, under Cylinder Head. It's not describing any procedures, just giving general info.

How about a page number like 15.4 or 15.32. Or even better...how about a scan. Im not saying you are wrong Id just like to read it with my own eyes.

No problem Kudagra.

Here it is: http://i2.tinypic.com/ritapi.gif

It's huge. If your browser makes it tiny and unreadable, click on it and it should come up full size.