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fccperdiem
Samba Member
Joined: August 16, 2005
Posts: 107
Location: Ellsworth, Maine
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 Posted: Wed Mar 26, 2008 12:43 pm Post subject: 74mm stroke with 88mm P/Cs |
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Can you use standard length 88mm cylinders with a 74mm stroke crank? Thanks guys.
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Eric
Beard Fire Metalworks
Ellsworth, ME
207-242-0016
www.beardfiremetalworks.com |
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SeVVenth
Samba Member
Joined: August 18, 2005
Posts: 678
Location: Winterset, Iowa
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| Posted: Wed Mar 26, 2008 12:48 pm Post subject: |
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| To my knowledge, aren't all barrels the same height? The only difference is in the Rod length and stroke. |
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Stripped66
Samba Member
Joined: May 31, 2005
Posts: 3470
Location: Charleston, SC
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| Posted: Wed Mar 26, 2008 12:57 pm Post subject: Re: 74mm stroke with 88mm P/Cs |
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| fccperdiem wrote: |
| Can you use standard length 88mm cylinders with a 74mm stroke crank? Thanks guys. |
Yes.
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| 66brm wrote: |
| Bodacious wrote: |
| Why not just make a custom set of wires with a Y splice in them. Then you could just run one distributor. |
I don't think electrickery works that way |
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fccperdiem
Samba Member
Joined: August 16, 2005
Posts: 107
Location: Ellsworth, Maine
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| Posted: Wed Mar 26, 2008 1:24 pm Post subject: |
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Now SeVVenth has got me thinking... I thought that the only difference between stroker and non-stroker cylinders was the length. Am I way out in left field?
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Eric
Beard Fire Metalworks
Ellsworth, ME
207-242-0016
www.beardfiremetalworks.com |
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purity
Samba Member
Joined: August 11, 2007
Posts: 174
Location: Norway
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| Posted: Wed Mar 26, 2008 1:42 pm Post subject: |
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| fccperdiem wrote: |
| Now SeVVenth has got me thinking... I thought that the only difference between stroker and non-stroker cylinders was the length. Am I way out in left field? |
You can get extra long cylinders for very long strokes and/or connecting rods, but the usual difference between long stroke (B) and regular (A) cylinder/piston sets is that the pistons are shorter and has the wrist pin further up in the piston.
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- '67 1300 (Original)
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Glenn 
Mr. 010
Joined: December 25, 2001
Posts: 76937
Location: Sneaking up behind you
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| Posted: Wed Mar 26, 2008 1:44 pm Post subject: |
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A 74 stroke can still use "A" pistons and cylinders.
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Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"
Member #1009
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fccperdiem
Samba Member
Joined: August 16, 2005
Posts: 107
Location: Ellsworth, Maine
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| Posted: Wed Mar 26, 2008 4:13 pm Post subject: |
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Thanks everyone.
I'm attempting my own version of a MPG motor. We'll see how it goes...
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Eric
Beard Fire Metalworks
Ellsworth, ME
207-242-0016
www.beardfiremetalworks.com |
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nsracing
Samba Member
Joined: November 16, 2003
Posts: 9471
Location: NOVA
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| Posted: Thu Mar 27, 2008 12:38 am Post subject: |
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| fccperdiem wrote: |
| Now SeVVenth has got me thinking... I thought that the only difference between stroker and non-stroker cylinders was the length. Am I way out in left field? |
The cylinders might be the same height but the piston pin heights are higher in the "B-series" pistons.
And yes. The 74mm will take the A-series non-stroke pistons. I will just build it with stroker pistons and long rods...if you wanted the most out of it. Higher piston pins = less piston slaps. Longer rods = more duration and less piston slap also.
More work to use long rods but I think they are worth it. |
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Don'sminiT
Samba Member
Joined: June 12, 2007
Posts: 23
Location: Hanover, Pa
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| Posted: Sat Mar 29, 2008 11:52 am Post subject: |
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| Cheap way cut .100 off top of A type piston, works with mild cam NO Ibrows on piston. OR Put .100 shim under barrels. Works for me. |
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jamestwo
Samba Member
Joined: November 01, 2004
Posts: 2203
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| Posted: Sat Mar 29, 2008 1:25 pm Post subject: |
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All the Cima/ mahles cylinders are the same.
The difference is the pin height on the pistons. For a 74mm crank, you can only use the stock stroke pistons, unless you want a lot of deck or pay for a lot of machine work.
The difference in deck height between stock and stroker cranks is half the stroke increase.
74mm-69mm=5mm
5mm X .5= 2.5mm difference in needed deck
2.5mm = .09843 of inch. So the above mentioned . 100 shims puts you almost perfect and only adds less than a 1/4 to the engine width.
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hEY, lOOK, i'M WRONG HALF THE TIME, AND THE OTHER HALF i'M NOT SURE WHAT THE HECK i'M TALKING ABOUT. MY POST ARE FOR MY OWN ENTERTAINMENT VALUE ONLY. |
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vwairheads
Samba Member
Joined: March 26, 2007
Posts: 675
Location: chula vista
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| Posted: Sun Mar 30, 2008 2:40 pm Post subject: |
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| hi, what is the stock 1600cc deck hieght? |
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jamestwo
Samba Member
Joined: November 01, 2004
Posts: 2203
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| Posted: Sun Mar 30, 2008 2:47 pm Post subject: |
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Deck hieght varies by year, but was from .050-.070.
Pin height on the piston is 39.6mm, on stroker (B) pistons it is 34mm
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hEY, lOOK, i'M WRONG HALF THE TIME, AND THE OTHER HALF i'M NOT SURE WHAT THE HECK i'M TALKING ABOUT. MY POST ARE FOR MY OWN ENTERTAINMENT VALUE ONLY. |
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derRHDmeister
Samba Member
Joined: June 22, 2004
Posts: 560
Location: worldwide
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| Posted: Mon Apr 07, 2008 4:43 pm Post subject: |
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Hello, perrfect thread.
Im currently building a similar "stroker" motor for my '60 bus.
Im trying to go HEAVY DUTY and DURABLE with with ample torque to haul bunch of stuff on LONG trips. (speed isnt my concern, DISTANCE is)
Have RGB's w/ 4.12 gearing. Tall 27" tires (215/75r15)
Also lookin for Mileage on this, hence the singleport heads/ (OK?)
Heres what Im working on:
-74mm x 85.5mm (1699cc)
-polished single port heads
-dual 34mm carb kit from CB performance (elec choke)
Alll stock except special grind cam, full flow oiling, and a 30mm oil pump.
The question I have here is: what MODIFICATIONs other than the .100" shave on top of pistons? Clearance case? I plan to use stock vw rods, ok?
What else do I need to do? Any input or recommendations appreciated from anyone who has experienced this?
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Ask not what your bus can do for you, but ask what you can do for your bus.
| unclespanky wrote: |
| Piercy could dip those wheel cylinders between his cheek and gums and spit them out rebuilt. |
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turboblue
Samba Member
Joined: October 09, 2003
Posts: 4216
Location: Central Indiana
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| Posted: Tue Apr 08, 2008 8:00 am Post subject: |
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Why would you shave the piston?
I'm thinking the top of a Cima piston is only about .250" anyway.
You really want to take 40% off the top of your piston?
Perfectly OK to use a shim.
I'd think again about that 30mm pump too.
Overkill in about anything IMHO.
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Gary
Turbo VW Sand Drag Buggy
"If you don't run into the Devil every once in awhile, you must be going in the same direction!" |
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derRHDmeister
Samba Member
Joined: June 22, 2004
Posts: 560
Location: worldwide
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| Posted: Tue Apr 08, 2008 9:41 am Post subject: |
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| turboblue wrote: |
Why would you shave the piston?
I'm thinking the top of a Cima piston is only about .250" anyway.
You really want to take 40% off the top of your piston?
Perfectly OK to use a shim.
I'd think again about that 30mm pump too.
Overkill in about anything IMHO. |
Shims or Shave? Im asking for opinions/feedbacks. I have Mahles, but are they similar in design?
So you saying I should use .100 shims along w/ the shims for compression?? (not sure deck-height yet)
why is a 30mm pump overkill? I have one in my 1776cc (69x90.5)
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Ask not what your bus can do for you, but ask what you can do for your bus.
| unclespanky wrote: |
| Piercy could dip those wheel cylinders between his cheek and gums and spit them out rebuilt. |
Check us out @
Instagram: DeafVolks & BarndoorBuggy |
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miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
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| Posted: Tue Apr 08, 2008 10:03 am Post subject: |
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30mm pumps are often the cause of blown out oil cooler and oil filter seals, they just move too much oil for anything but a race engine. 26mm is more than enough for street cars, even turbo ones (I would know  ).
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Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
Welcome to the Samba. |
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derRHDmeister
Samba Member
Joined: June 22, 2004
Posts: 560
Location: worldwide
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| Posted: Tue Apr 08, 2008 10:33 am Post subject: |
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| miniman82 wrote: |
| 30mm pumps are often the cause of blown out oil cooler and oil filter seals, they just move too much oil for anything but a race engine. 26mm is more than enough for street cars, even turbo ones (I would know ). |
hmm interesting. I guess my 30mm in the 1776 is an overkill?
Ill stick with 26mm for this low compression torque motor, do you have any brand preference or a stock oil pump will do? Any modifications or just stick with what VW started with in first place?
And about the piston/cylinder- any recommendations? SHIMS/no shave?
Whats the maximum shims (in size) I can add to the cylinder to offset the stroke?
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Ask not what your bus can do for you, but ask what you can do for your bus.
| unclespanky wrote: |
| Piercy could dip those wheel cylinders between his cheek and gums and spit them out rebuilt. |
Check us out @
Instagram: DeafVolks & BarndoorBuggy |
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miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
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| Posted: Tue Apr 08, 2008 10:41 am Post subject: |
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To me, it's not so much about the size of the engine in question, it's the intended usage. Street engines I build get 26mm pumps, period.
I'm using CB performance's Maxi 5 pump, which is a Shadeck 26mm body, with CB's cover. The body is solid on the outlet side, so you don't have to worry about plugging the case.
As for the deck height issue, just measure to find the shim thickness you need, and order them. Places like Rimco can make any thickness shim you need. I would NOT monkey with the piston tops.
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Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
Welcome to the Samba. |
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derRHDmeister
Samba Member
Joined: June 22, 2004
Posts: 560
Location: worldwide
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| Posted: Tue Apr 08, 2008 1:47 pm Post subject: |
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| miniman82 wrote: |
To me, it's not so much about the size of the engine in question, it's the intended usage. Street engines I build get 26mm pumps, period.
I'm using CB performance's Maxi 5 pump, which is a Shadeck 26mm body, with CB's cover. The body is solid on the outlet side, so you don't have to worry about plugging the case.
As for the deck height issue, just measure to find the shim thickness you need, and order them. Places like Rimco can make any thickness shim you need. I would NOT monkey with the piston tops. |
Great Ill go with 26mm then...
Ill check with Rimco and see what they offer. Thanks AGAIN!
_________________
Ask not what your bus can do for you, but ask what you can do for your bus.
| unclespanky wrote: |
| Piercy could dip those wheel cylinders between his cheek and gums and spit them out rebuilt. |
Check us out @
Instagram: DeafVolks & BarndoorBuggy |
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