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Re: Type 4 buggy motor
Posted: Wed Oct 29, 2008 3:12 pm
by Tony Z
thats not a cermaic coating, its a thermal displacement coating. Same as what us used by the SA quad challenge team racing in the UAE to cool their quads
Re: Type 4 buggy motor
Posted: Wed Oct 29, 2008 3:27 pm
by AirPower
When the valves are coated - does that not affect the seat area? (In that they no longer seat properly) Can you grind them then to seal with the coating in place?
Re: Type 4 buggy motor
Posted: Wed Oct 29, 2008 3:40 pm
by JohnHoffe
The valve seats are not coated, also the valve stem that runs into your valve guide.
The thermal displacement coating is also used in your inlet port and inlet manifold. My personal concern with that is it tends to smoothe the port (personal choice). Some clever guys say the inlet port needs to be rough to assist atomising.
Something else Sartor Bros can assist you with is a K-liner (twirled valve guide) in the valve guide to lessen friction on the valve and assist with oil flow in that area. (minor mod, minor gain).
Re: Type 4 buggy motor
Posted: Wed Oct 29, 2008 3:48 pm
by Tony Z
You sure? The thermal displacement in the inlet port will transfer the heat of the head into the inlet charge, thus heating it.
On my heads I gave strict instructions not to coat the inlet port with anything.
Even if your valves seats are coated, the ceramic is still fairly soft (even after baking) and it hardens once the temp of operation heats it, so its nothing to grind off while lapping the valves in.
I dont like the K-liner idea. I have them in a set of heads tha tI have not used yet. I dont like the idea of the oil making its way down the sleeve and sitting there near the hottest part of the heat and just baking itself to carbon. Maybe on the inlet port it will be ok, but the thought of it in the exhaust port scares me.
Re: Type 4 buggy motor
Posted: Sun Feb 15, 2009 9:12 pm
by AirPower
At least this part of the buggy build is still going as planned. The engineering shop (ENSCO in VDBLpark) is done with the heads and case - opened them up to accept the bigger cylinders.
The ridge shown in the top photo will have to be remove, I'm worried that the cylinder spacers (that I'll have to install) will not seat very well on what is left there, so I'll have it machined down and flat in that area. The heads, well what can I say, they will accept the bigger cylinders, but somehow I need to find a way to fill up the 1mm cut that my American friend did (arrows). The cut moved the quench pads away from my dished pistons, so no squish available at this time, which is probably a bad thing

.
On to the QSC aluminum Nikasil cylinders. Some bad news there I'm afraid. The sealing edge on the heads side, were so bad that I had to have them machined down a little. This turned out to be a good thing, because they were found not to be of equal length, so we corrected that. Problem is machining the cylinders caused the Nikasil coating to chip around the top edge. Luckily the rings don't reach that far up (or out if you will), but I don't know what that means for longevity.
Now I've torqued up the empty case (bad photo, sorry - taken late tonight) to have the main bearing saddles checked for roundness and to make sure the crank is parallel with the case center line. This will be done during this week. Looks like I'm going to have the motor up-and-running before the buggy is even ready to accept the performance motor.
Cheers - I'll keep you updated.
Mario
Re: Type 4 buggy motor
Posted: Mon Feb 16, 2009 3:54 am
by beetlefanatic
Nice one Mario. Keep the pics coming!
Re: Type 4 buggy motor
Posted: Mon Mar 09, 2009 9:07 am
by Wentzel
Very nice!! I can't wait to see the final result! You will convince me to try the typeIV also.
Keep us up to date pls. . .
Re: Type 4 buggy motor
Posted: Tue Mar 10, 2009 8:12 pm
by AirPower
Got some hen's teeth - German made main bearings. 0.020" oversize in the case and std on the crank.
Just goes to show - industry needs people with memory like an elephant - the shop was starting with the whole "OH no! we'll have to order these, VERY difficult to find" when the one guy remembered about these on the shelf. Was ordered for a customer years ago, but he wanted 0.020" on the crank and std in the case.
R400.00
Someone smiled on me that day

.
Played the lotto, but won nothing - so that was that for me for the rest of the year.

Re: Type 4 buggy motor
Posted: Sat Mar 14, 2009 5:56 pm
by Bugger
Mooi that was a score