Piston info

Top End (cylinders and heads)
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bigduke
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Piston info

#1

Post by bigduke » Sun Apr 18, 2010 8:11 pm

Hello all,
This is my first post. I don't own a Panhead but have a few British bikes. I am currently working on a Norton single engine, turning it into a short stroke and I am looking for a suitable piston. I am incorporating a squish band on the head and ideally require a flat top piston. A slight dome would probably do.The Panhead piston might do the trick at 3 7/16" dia but I can't find any more suitable information on these pistons. Most info that I have found only give compression ratio and rod length but no piston dimensions. Possibly someone on this forum can answer a couple of questions for me.

Do pan heads have flat top pistons?
What is the compression height? I am looking for 1 5/8"
What is the wrist pin diameter?
Are there any web sites to visit that might have a list of pistons with the info that I am looking for.

Cheers
Duke



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Re: Piston info

#2

Post by RUBONE » Mon Apr 19, 2010 1:59 am

Pan head pistons are domed. They are a Hemi-head design so need that. ULH/UH pistons are flat topped and 3 7/16 in diameter.
The piston pin is .790 in.
The compression height is approx. 1.75 in.
Not sure of any lists!
Robbie

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Re: Piston info

#3

Post by FlatHeadSix » Mon Apr 19, 2010 4:34 am

Duke
Welcome to the forum.

WISECO has been a very reliable piston source, you might give them a try:
http://www.wiseco.com/Default.aspx

mike

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Re: Piston info

#4

Post by NightShift » Mon Apr 19, 2010 4:32 pm

Dear Duke,
If you can tell me your perfect or biggest possible pin size, then maybe I can look up other old motor pistons in an Egge catalog that come close.

Hope I can help,


PS: It looks like all Harley big twins use .791 pins and J models have the shortest compression height at 1.6515 and Us are 1.750 and overheads are a whopping two and three eighths!

Theres an odd piston listed at 1.58 with a .8003 pin, but no clue what it fits or anything else.

bigduke
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Re: Piston info

#5

Post by bigduke » Mon Apr 19, 2010 7:27 pm

Thanks fellas.
I found this geat site today.http://knuckleheadtheology.blogspot.com ... gines.html It shows that the 61" piston has a 1.625" comp height. I guess that there will be different dome heights. Any idea of the weight of these pistons?
Nightshift,
The stock pin dia for the Norton is 0.875"
Cheers
Duke

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Re: Piston info

#6

Post by RUBONE » Mon Apr 19, 2010 10:00 pm

Duke,
61" pistons are only 3 5/16 in diameter!
Robbie

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Re: Piston info

#7

Post by friday » Fri Aug 17, 2018 6:14 am

NightShift wrote:
Mon Apr 19, 2010 4:32 pm
Theres an odd piston listed at 1.58 with a .8003 pin, but no clue what it fits or anything else.


this odd ball is a corvair piston dia = 3.437" , CH =1.578" , pin =.8003" , OAL = 3.190"

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