Mahle Nikasil 90ZN4 cylinder and pistons

[tigerdyr]

I have a set of Mahle Nikasil 90ZN4 cylinder and pistons.

I would like to use them on my 1600 single port, but what about the head torque?? My engine blok have 8mm head studs.

What are people's experiences on this??

[Dr OnHolliday]

As far as I know, just use the correct torque for 8 mm studs
_________________
1965 Type 1 sunroof Baja / about 70k miles on self-rebuilt '74 1600 and counting / SP heads and aftermarket valve keepers / non-doghouse shroud with external cooler and filter / 1.5 qt extended sump / Weber 32/36 DFAV progressive carb / 009 dist with Pertronix / 1.25 ratio rockers and ball adjusters / 1.5" stainless steel J-pipes and carbon steel baja exhaust

[tigerdyr]

Mmm okay...

I know that Ln Engineering are making some head studs for Nickies.
I know that Ln cylinders are a bit different but will that work for my cylinders??

[andy198712]

are they alu coated with nikasil?
_________________

[tigerdyr]

They are alu cylinders caoted with nikasil.

[andy198712]

i would maybe email LN and see what they recommend for their nikis? as they'll explained at different rates to standard VW cylinders.

Where did you find these?
_________________

[tigerdyr]

I found them here on the samba

[modok]

That's a good question. Seems likely that you could use a few ft-lb less. Sorry I don't know anybody who ever used those.......... they must be 30+ years old!

[tigerdyr]

I do not know how old they are. There are used but in good condition.

[slalombuggy]

IICR the 911 engines I built with Nic cylinders had the same head torque with 8mm studs. Just remember to be VERY carefull with these cylinders and do not scratch the cylinder walls. Honing is also definitely out of the question,

brad

[karolp]

I have same p&c for my engine. I asked exactly the same question here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=448037&highlight=

Conclusion was to use stock torque specs.

[tigerdyr]

Ok thanks

Missed that thread. ..

[Danwvw]

[mark tucker]

eye wood go with stock 88 stud tq and use a copper head gadget to keep from fretting. and I would also retorque after a week or so of heat cycles. and use proper nut/washer/stud lube/sealer

[andy198712]

nut friction? are you talking about locking nuts?

ideally there should be no nut friction (less then a lb anyway) on a normal plain nut, IE can but threaded down easily by hand till it contact.

if nylocs ect, you "should" measure run down torque other wise you'll be under talking the bolt....
_________________

[Danwvw]

No not self-locking nuts! But good point! Just regular head nuts and washers. It's probably a bigger deal on 10mm studs where the big 17mm nuts are used. More surface area.
Because you can get oil leaks around the head nuts and washers it's important they be new or sanded flat again. Last engine I did I used Curl-T to seal the oil out around the studs and nuts. Before I would use Silicone RTV but it can't be retorqued later without breaking its seal. Curl-T seems like it solved the problem of re-torquing.

Wonder if Nylon Seal Nuts could be used for head nuts on an air-cooled still would need a face seal of some kind.
_________________
1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Alstrup]

No no no, NO copper shims between heads and Nikasil cylinders please.

Yes use stock 8 mm head studs, yes use stock torque (28 nm)

T