Hi Guys.. will this fit? I think it will. Are these heads the same or are there differences.. extra coolant passages etc..

And I mean the hydro heads..   Just wondering what the differences are and if there are any.. as N/A heads are easier to find over here..

You mean these squirters under the piston?



Yeah I know about that..

Just wanna know why a TD head is preferrable... I also know it bolts on.. I have compared headgaskets of both and could not find anything different aswell...

The part number for replacement head castings (that is, assembled with valve seats) of a 12mm head-bolt 1.6 NA head is the same as a 1.6lTD head.

If you look at the heads that actually came off 1.6lTDs and 12mm 1.6lNAs, the casting numbers actually cast into the heads (which don't correlate to any part number it ETKA  :? ) are different.  So, there is a possibility I suppose the metal content is different.  Although there is also strong evidence (replacement part numbers being same in ETKA) that VW already incoporated the changes for turbo into the 12mm-head bolt 1.6lNA heads.

If you get a 1.6lNA head intending to put it on a 1.6lTD and have a chance to rebuild it, I'd recommend replacing the valves with turbo parts during the rebuild.  Specifically, I think it's just the intake valves that ETKA lists are different vs the NA vs Turbo 1.6l heads.

Thnx for the info Guys...

Wonder what the difference would be than with the intake valves..  Natrium filled valves?

None of the VW Diesel valves that I am aware of are sodium (element "Na") filled.  The 1.6l naturally aspirated diesel intake valve is part number 068 109 601 D, while the 1.6lTD intake valve is 068 109 601 C.  Maybe buy one of each, take a close look and let us know!

Exhaust valve has part number 068 109 601 D for both the solid lifter 1.6lNA and 1.6lTD motors.

The only visual difference I have ever found is the little mark on the prechamber. The TD prechambers have a triangle shaped mark and the NA prechambers have a round dimple. Other than that one cannot tell the difference by looking.

As I've said before, there is no dispute that when the TD was first engineered back in the early 80's, vs the early, 11mm head bolt, 1.6l NA motor of the time, there were indeed many differences NA to TD.  These are well documented in multiple reliable sources, however the best, most thorough, and most original source is VWoA's "Introductory Service Training Information, 1982 Quantum Turbo-Diesel" Pamphlet.  This seems to be the only source of information that was used for the TD-specific pages in the Bentley manual.  Another good source is the 1.6lTD SAE Paper but it's not as complete as the Introductory Service Training pamphlet.

However, it is also clear that at least some of these changes were carried over to 1.6lNA production in the mid-'81 model year.  With this update of the 1.6lNA motor, it's crankshaft changed to the TD-style snout, and it's head bolts were upgraded to the TD-spec 12mm versions.  It is not conclusive but it wouldn't surprise me if other TD-spec changes were migrated over at that time, for example changes to valve materials, head casting materials, etc.  And in fact information from ETKA on replacement parts seems to imply this.

There isn't a complete list of differences from a reputable source, comparing a late model solid lifter, say '83 or '84 1.6lNA motor to a solid lifter 1.6lTD.

To assume that all these changes between NA and TD exist in the '83 and '84 1.6lNA vs TD motors exist simply isn't true, as it it taking the only 2 original sources of information regarding changes between 1.6lNA and 1.6lTD: the 1.6lTD SAE Paper, and the 1982 Quantum Turbo Diesel Introductory Service Training Information manual out of context.  The Normally aspurated engines being compared in both of those sources are early, pre-TD development motors.  Not the later, 12mm-head bolt, updated crankshaft iterations that is more common to us now.

Although I can't rule out the possibility that ETKA changed part numbers over time, it's also pretty hard to refute when ETKA says 1.6lNA and 1.6lTD gets the same part number, that it's not true.

Still not conclusive either way.

The only official data on changes between NA and TD I've ever seen are comparing the 12mm head-bolt TD to the 11-mm head bolt NA.  If you have anything else, I'd be interested in seeing it.

It is also undisputed that VW put the 12mm head bolt head, which was an upgrade specifically designed for TD application, into their NAs in the '81 production model year.  It is also undisputed that VW also updated the crankshaft to the style of snout design for TD application (harmonic balancer compatible) also at this same time.  These changes can be readily observed by disassembling original VW engines and observing the parts.

I recently read somewhere that the types of metal are different and that the valve seats are harder.  Then again, I know people who have put significant mileage on N/A motors with turbos bolted on.  Not even a TD pump!!