Modified 100mm Porsche 964 Nikasils - Progress

This is the place to discuss, or get help with any of your Type 4 questions.
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Wally
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Modified 100mm Porsche 964 Nikasils - Progress

Post by Wally » Thu Jan 15, 2004 4:37 pm

Hi,
As promised I will try to post some pics that I could save on our dutch website and redirect here.
A few more pics will be posted as my pic hosting skills and the capacity of the host site will allow...
Description of the work done can be found in the thread "Hey Wally", one page or so back on this forum.

Image
These are the redrilled cylinders.
Image
These are an unmodified and not cleaned set of used piston and cylinder and a modified set.

Greetings,
Walter
T4T: 2,4ltr Type 4 Turbo engine
www.apfelbeck.nl
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks

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Wally
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Post by Wally » Thu Jan 15, 2004 5:13 pm

Image
Image

Image
This is a 914 2,0 ltr head, cut mirror wise for the pistons with a 1,5 mm clearence. Deck height will be set at appr. 1,0 mm.
With that deck heigth I will need spacers of around 7mm. The spacers will be very 'wide' since the area around the studs will also sit on the machined case (cylinder area machined down).
Note that we have not machined the top fin off one bit. Also the ridge on which the cylinder will rest is not turned down, all to maintain maximum strenght and as much cc's in the head as possible.
The head has not been been ported or flowed yet and probably will not also. The area besides the valves will have to be 'unshroud' as it is called I believe. That procedure will also be used to cc the heads for the final CR. Not sure what it will become, but hope somewhere around 1:10,5

I hope its all clear at bit

Greetings,
Walter
T4T: 2,4ltr Type 4 Turbo engine
www.apfelbeck.nl
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks

MASSIVE TYPE IV
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Post by MASSIVE TYPE IV » Thu Jan 15, 2004 5:23 pm

SWEET!

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Wally
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Post by Wally » Thu Jan 15, 2004 5:30 pm

Thanks Jake,
That does mean s/th to me.
Take care,
Walter
T4T: 2,4ltr Type 4 Turbo engine
www.apfelbeck.nl
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks

MASSIVE TYPE IV
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Post by MASSIVE TYPE IV » Thu Jan 15, 2004 5:31 pm

:mrgreen:

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Wesayso
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Post by Wesayso » Thu Jan 15, 2004 5:39 pm

Hmmmm, interesting....

Now if I could copy that and.... :wink:

Great stuff Wally!

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Bobtail
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Post by Bobtail » Thu Jan 15, 2004 7:52 pm

Nice crown ,Shame you aint usin the head to go with it :lol:

How many km's do those have on them?Do you know?

Compared to the supervee pistons I used to have You should be in the right ballpark compression-wise.

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Piledriver
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Post by Piledriver » Thu Jan 15, 2004 8:24 pm

Bobtail---Perhaps you could set him up?
Addendum to Newtons first law:
The longer a vehicle rests on jackstands,the more likely it is to remain that way...

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Wally
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Post by Wally » Fri Jan 16, 2004 3:05 am

Bobtail wrote: How many km's do those have on them?Do you know?
That set had about 90.000 km (60K miles?) on them.

Really, there is not a mark on the piston wall to be seen. I mean, all the original porsche machining marks in horizontal direction are unmarked on the piston! One would assume, since the piston travels up and down, that vertical marks would be there, but nothing. Its truly amazing. Also because the piston and cylinder have a much tighter fit than I'am used to.

The barrel, once cleaned, is also super smooth at both TDC and BDC. All honing cross threads are still there. Just because of the quality of these parts, its a feast to work with them.

Also, after seeing these alu, Nikasil cylinders you are spoiled! I assure you.

Walter
T4T: 2,4ltr Type 4 Turbo engine
www.apfelbeck.nl
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks

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Richie
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Post by Richie » Fri Jan 16, 2004 4:35 am

Hello,

Darn Wally, you got me all giddy again :wink: ! It looks awesome and more doable than I imagined, think should have measured my set a bit better. My compliments to Roberto as I assume he has done the machining. Offcourse you get my compliments as well.
Now, mine's a turboset, soooo....... :D

Cheers,
Richard

roberto
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Post by roberto » Fri Jan 16, 2004 1:24 pm

Looks Great!!!!
Very good idea :wink:

greetings Roberto

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njv
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Post by njv » Fri Jan 16, 2004 8:31 pm

hello wally

that looks very interesting indeed very doable ive a wilco tame machinist just in the next vilage from me!!! any chance you could post a picture of what you mean at the case opening with the spacer and stuff?

good luck with it.

roo
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Post by roo » Tue Jan 20, 2004 3:47 pm

wally got your email, came over for a peak, and great stuff. my only question: does the raised section of the piston have a dish to it or is it just machined flat. i can't imagine it being dished but i can't quite tell in the one pic if it is or istn't.

roo
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Post by roo » Tue Jan 20, 2004 3:56 pm

i guess in the other pic that i missed :oops: it looks pretty darn flat. but is that a hole in the middle that needs to be weleded up?

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Wally
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Post by Wally » Tue Jan 20, 2004 4:27 pm

Haha, no thats not a hole ! Please!

The original piston has a slight dent in the middle, but because I haven't cleaned or polished anything in the pics, that dent is still black from carbon residue, so are the two dimples left and rigth.
Those two are original valve pockets for the porsche inlet and exhaust valve.
I may have to machine valve pockets for the type 4 valves later on. I have not measured that yet.

Take care,
Walter
T4T: 2,4ltr Type 4 Turbo engine
www.apfelbeck.nl
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks

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