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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21520
Location: Oklahoma City
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21520
Location: Oklahoma City
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 Posted: Sat Sep 21, 2019 7:34 pm Post subject: Re: dished pistons |
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| Alstrup wrote: |
Arrhh, more like 4. I´m pretty sure its 4 cc.
For the person asking about domed 1800 pistons. They are from the AN engines. I have not seen a new set in many years. But, I havent looked that hard either. Around here most people that build/rebuild type 4´s go directly to 2 liter or more. |
You are closer to right...dont know where my brain was getting that.
Below are some calculations and measurements from a new/NOS 1.7L domed piston set I got last week from Heimlich. They are Nural brand from Germany and seem to be quite nice pistons. I will do a review of them this week.
One thing I have found over the years is that there is a little bit of difference from brand to brand. I will post the Nural measurements and then a measurement from my logbook from a build with a KS set from the mid 90s...where the dome lower diameter is about 0.180" larger in diameter than these with the top area of the dome being the same amount larger in diameter...height being the same at 0.075. This is still only in the 5.47cc range.
Here are the Nural measurements.
Here is the calculation of the trapezoidal cylinder that dome represents...in cubic inches. So the conversion is 4.674CC
Here is the calculation for the KS piston domes from many years ago. The conversion is 5.471 cc
I have thought about having the piston top surrounding the dome turned down on a set by about 0.050". This will increase dome height by .050". On the Nural set for instance this would increase dome volume to 7.79cc
Ray |
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oprn
Samba Member
Joined: November 13, 2016
Posts: 12739
Location: Western Canada
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| Posted: Sat Sep 21, 2019 7:24 pm Post subject: Re: dished pistons |
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Last edited by oprn on Sun Sep 22, 2019 4:41 am; edited 1 time in total |
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H2OSB
Samba Member
Joined: April 14, 2013
Posts: 1294
Location: Modesto, CA
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| Posted: Sat Sep 21, 2019 7:05 pm Post subject: Re: dished pistons |
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| Alstrup wrote: |
Arrhh, more like 4. I´m pretty sure its 4 cc.
For the person asking about domed 1800 pistons. They are from the AN engines. I have not seen a new set in many years. But, I havent looked that hard either. Around here most people that build/rebuild type 4´s go directly to 2 liter or more. |
Fair enough. I'm gonna have to measure
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(o\_i_/o) I'm not a vegetarian because I love animals, I'm a vegetarian because I hate plants. |
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H2OSB
Samba Member
Joined: April 14, 2013
Posts: 1294
Location: Modesto, CA
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| Posted: Sat Sep 21, 2019 6:24 pm Post subject: Re: dished pistons |
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Ray--
I will say I placed the crown the the domed pistons head to head with the crown of my 3cc pistons and they fit together without interference. Ugh...perhaps my 3cc pistons are, in fact, 7cc pistons.
Guess I'll impatiently wait for your measurements. 
H2OSB
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(o\_i_/o) I'm not a vegetarian because I love animals, I'm a vegetarian because I hate plants. |
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Alstrup
Samba Member
Joined: July 12, 2007
Posts: 7219
Location: Videbaek Denmark
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| Posted: Sat Sep 21, 2019 5:33 pm Post subject: Re: dished pistons |
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Arrhh, more like 4. I´m pretty sure its 4 cc.
For the person asking about domed 1800 pistons. They are from the AN engines. I have not seen a new set in many years. But, I havent looked that hard either. Around here most people that build/rebuild type 4´s go directly to 2 liter or more. |
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21520
Location: Oklahoma City
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| Posted: Sat Sep 21, 2019 4:51 pm Post subject: Re: dished pistons |
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| H2OSB wrote: |
Ray--
Do you know what the CCs of the dome is? They almost look to be exactly opposite of my 3cc dished pistons.
H2OSB |
I believe they are actually about 7CCs. I will check tonight. Ray |
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walter kandetzki
Samba Member
Joined: June 02, 2003
Posts: 918
Location: Dillwyn, VA
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| Posted: Sat Sep 21, 2019 4:18 pm Post subject: Re: dished pistons |
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walter kandetzki
Samba Member
Joined: June 02, 2003
Posts: 918
Location: Dillwyn, VA
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| Posted: Sat Sep 21, 2019 3:56 pm Post subject: Re: dished pistons |
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| finally got the engine today from my buddy.found out the pistons and cylinders are OEM vw.even has the logo on the cylinder.still going to end up running 96mm set up though and put a cb performance cam.the motor had been rebuilt so it is stupid clean on inside |
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H2OSB
Samba Member
Joined: April 14, 2013
Posts: 1294
Location: Modesto, CA
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| Posted: Fri Sep 20, 2019 5:43 am Post subject: Re: dished pistons |
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Ray--
Do you know what the CCs of the dome is? They almost look to be exactly opposite of my 3cc dished pistons.
H2OSB
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(o\_i_/o) I'm not a vegetarian because I love animals, I'm a vegetarian because I hate plants. |
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heimlich 
VWNOS.com
Joined: November 20, 2016
Posts: 6617
Location: Houston, Texas
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| Posted: Sun Sep 15, 2019 8:43 am Post subject: Re: dished pistons |
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| raygreenwood wrote: |
Also take a look at their catalog on that site under 411/412. They have a reasonable amount of parts in stock. I like that they stock virtually everything Beru for the ignition....cap, rotor, points (if you still use them) angle and straight resistor wire ends and Goetze ring sets. Ray |
Let me know if you need anything. I can order from them or at least check pricing.
_________________
www.vwnos.com [email protected]
Classic Brands. Classic Quality.
Not all parts are made the same. NOS OE/OEM parts made mainly in West Germany, Early Germany, and Early Brazil are where VW produced the best quality parts and best fitting products.
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21520
Location: Oklahoma City
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| Posted: Sat Sep 14, 2019 10:15 pm Post subject: Re: dished pistons |
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| heimlich wrote: |
| raygreenwood wrote: |
| heimlich wrote: |
| There's a good story behind those pistons. Now I have more stories to add to it. Glad to see they got into the hands of some TheSamba folks. |
Tell us how you came in the possession of these please!
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Those pistons came with all the other type 4 parts I have. They had been sitting for many years waiting for me.
Federal Mogul has so many brands. Wow! |
Also take a look at their catalog on that site under 411/412. They have a reasonable amount of parts in stock. I like that they stock virtually everything Beru for the ignition....cap, rotor, points (if you still use them) angle and straight resistor wire ends and Goetze ring sets. Ray |
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heimlich
VWNOS.com
Joined: November 20, 2016
Posts: 6617
Location: Houston, Texas
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| Posted: Sat Sep 14, 2019 9:44 pm Post subject: Re: dished pistons |
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| raygreenwood wrote: |
| heimlich wrote: |
| There's a good story behind those pistons. Now I have more stories to add to it. Glad to see they got into the hands of some TheSamba folks. |
Tell us how you came in the possession of these please!
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Those pistons came with all the other type 4 parts I have. They had been sitting for many years waiting for me.
Federal Mogul has so many brands. Wow!
_________________
www.vwnos.com [email protected]
Classic Brands. Classic Quality.
Not all parts are made the same. NOS OE/OEM parts made mainly in West Germany, Early Germany, and Early Brazil are where VW produced the best quality parts and best fitting products.
5% Off your order with coupon code: 5%OFF
Restored Distributors Available (<--Click here) |
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21520
Location: Oklahoma City
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| Posted: Sat Sep 14, 2019 8:45 pm Post subject: Re: dished pistons |
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| heimlich wrote: |
| There's a good story behind those pistons. Now I have more stories to add to it. Glad to see they got into the hands of some TheSamba folks. |
Tell us how you came in the possession of these please!
I will be the first to admit that I had never heard of Nural pistons. Months ago when I first saw your ads I started digging online and asking around. I heard nothing but EXCELLENT about Nural.
Its a fairly well regarded European OEM mfg of pistons....owned by Federal Mogul. Their website notes that they use Goetze rings on their piston sets. I dont know if thats recent or has always been.
https://www.fmmotorparts.eu/brands/nural.html
The European motorcycle guys like these pistons and teh Mercedes and BMW guys have had good things to say.
Depending on how my contracts go this month if you still have any left I may buy one more set.
I know there are people...in this forum...reading this thread and asking...all this crap for a 1.7?
Yeah...well...its pretty much the best running stock engine VW ever built...IMHO. They get an easy 150k miles, have 80-82 hp from the factory...can be tweaked in stock form with stock injection and a few parts to have an easy 90hp. They are tough as a boot. Best overall head design in reliability of the type 4 series....with a piston design made specifically to work with that head (or is it vice versa).
Most people that use a 1.7L in stock or near stock form are putting them into restoration 914's or 411/412. The value of that engine in a restoration car is far better than most other options. Ray |
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H2OSB
Samba Member
Joined: April 14, 2013
Posts: 1294
Location: Modesto, CA
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| Posted: Sat Sep 14, 2019 8:25 pm Post subject: Re: dished pistons |
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This guy is a very nice guy ^^^. Thank you
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(o\_i_/o) I'm not a vegetarian because I love animals, I'm a vegetarian because I hate plants. |
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heimlich
VWNOS.com
Joined: November 20, 2016
Posts: 6617
Location: Houston, Texas
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| Posted: Sat Sep 14, 2019 7:47 pm Post subject: Re: dished pistons |
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There's a good story behind those pistons. Now I have more stories to add to it. Glad to see they got into the hands of some TheSamba folks.
_________________
www.vwnos.com [email protected]
Classic Brands. Classic Quality.
Not all parts are made the same. NOS OE/OEM parts made mainly in West Germany, Early Germany, and Early Brazil are where VW produced the best quality parts and best fitting products.
5% Off your order with coupon code: 5%OFF
Restored Distributors Available (<--Click here) |
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21520
Location: Oklahoma City
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| Posted: Sat Sep 14, 2019 4:20 pm Post subject: Re: dished pistons |
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| APPLEGREENVW wrote: |
| Are 93mm dome pistons hard to find? |
I have personally never seen a set of 93mm dome. I think there may have been some 94mm domes for Porsche 914 2.0L.
And....H2OSB....the whole discussion kind of forced my hand as well. I have been contemplating these for a while but just had too many other items and they appeared to be moving slowly enough. Your predicament just reminded me of how hard I have to look for domes and how bad availability is.....and i do not want to go through it in spades 5 years down the line.
So i bought a set last night...and also hoped that would poke you in the ribs....
I always say...if its rare and you know you need it...sometimes you just have to bite the bullet and get it way in advance before you need it.
I tell this to the bus people all the time. They think their NOS stuff is starting to "dry up"?....our shit for these 1.7 engines and for 411/412....started as nothing but a damp spot in the first place.
Get it while you can because it will be gone at some point.
Hang onto your dished piston set. 3mm dishes are not as common as the larger dishes. Someday they may be better than whats available.
Ray |
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APPLEGREENVW
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Joined: November 30, 2003
Posts: 2388
Location: Seekonk,Massachusetts USA
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H2OSB
Samba Member
Joined: April 14, 2013
Posts: 1294
Location: Modesto, CA
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| Posted: Sat Sep 14, 2019 1:52 pm Post subject: Re: dished pistons |
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Ray--
Fear that I might miss out has forced my hand. I bought a set of the domed pistons as well. Now my CR issue is solved. And, I now have a spare set of pistons with a 3cc dish. Just sayin.....
The guy is down 4 sets so anyone else who's thinking about getting a set may want to step up the pace.
H2OSB
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(o\_i_/o) I'm not a vegetarian because I love animals, I'm a vegetarian because I hate plants. |
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raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21520
Location: Oklahoma City
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| Posted: Fri Sep 13, 2019 6:25 pm Post subject: Re: dished pistons |
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| H2OSB wrote: |
I've actually written to that guy, and considered buying a set. Perfect for my needs. I'm just not sure I can convince my wife of my need.
Let me ask this...considering those would give 8.2 CR in a stock set up, if I were to lose the base shims and head gasket, would I get to 8.5?
H2OSB |
Probably close. Last time I got to right at 8.4:1 with no other changes. If you have a very small flycut done just to clean up you may get 8.5:1. Each head is a little different over the years depending on valve margin and valve diameter.
A few people have gotten 8.5:1 with no other mods.
I just purchased a set of his pistons 5 minutes ago. He has 6 sets left. I figured with how hard they are to find now...I do not want to be making the same search you are in five years. In fact....its been this hard to find domes for quite some time now. I went through a 6 month search to find the set I have now I bought 8 years ago.
Ray |
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