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 Post subject: rockers
PostPosted: Mon Dec 17, 2012 12:41 pm 
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848cc
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Joined: Fri Dec 12, 2008 3:07 pm
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Location: tasmania
Hi, you are talking about 1.3 and 1.5 rocker . What are the difference to std thanks
:?: :?: :?:


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PostPosted: Mon Dec 17, 2012 12:50 pm 
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SooperDooperMiniCooper ExpertEngineering
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Location: Under the bonnet son!
The Doc is all over this like a rash and will drop some figures in with a bit of luck later, but it seems standard rockers (including Cooper S forged type) are unreliable in their exact ratio and don't often make 1.3:1.

Aftermarket rockers promise a better known ratio with 1.5:1's promise a little more valve lift without having to change your cam shaft out.

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All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.


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 Post subject: rockers
PostPosted: Mon Dec 17, 2012 12:52 pm 
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848cc
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Joined: Fri Dec 12, 2008 3:07 pm
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Location: tasmania
ok so what one the best and where can you get them or from what vehicles thanks


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PostPosted: Mon Dec 17, 2012 12:56 pm 
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848cc
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Joined: Tue Apr 05, 2011 9:48 pm
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Location: Gisborne VIC
Plennnnnty of discussion if you do a search for rockers in the minichat section

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PostPosted: Mon Dec 17, 2012 1:13 pm 
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Location: near Baulkham Hills, NSW
Mick wrote:
The Doc is all over this like a rash and will drop some figures in with a bit of luck later, but it seems standard rockers (including Cooper S forged type) are unreliable in their exact ratio and don't EVER make 1.3:1.

Aftermarket rockers promise a better known ratio with 1.5:1's promise a little more valve lift without having to change your cam shaft out.


Fixed for ya Mick.

I tested all the rockers (except 1275 pressed steel) with a new RE13 cam, and a 12G1316 (1275) head.

From file:
22/7/07 Checked valve lift- 12G1316 head fully assembled.
RE13 cam (.290" lobe lift), stock pushrod, valve clearance .016”:

Lift at #1 inlet valve-
S forged rockers 0.321”(1.16:1)
A+ sintered rockers 0.327”(1.18:1)
998 Deluxe rockers, cast iron posts 0.337”(1.21:1)
998 Deluxe rockers, A+ sintered posts (are 0.3mm shorter than CI) 0.339”(1.22:1)

998 Deluxe rockers, cast posts lowered 0.6mm, offset bushed 1.0mm. 0.359”(1.29:1)
998 Deluxe rockers, cast posts lowered 0.6mm, offset bushed 1.1mm 0.365”(1.31:1)
1275 pressed steel rockers, offset bushed .044” (1.1mm) 0.376”(1.35:1)
Corolla rockers, late `sintered rocker’ type posts, shaft offset 3.9mm 0.402”(1.44:1)


I used to offset bush the pressed steel ones, that gave 1.31:1. However you can buy new 1.3 Minisport roller ones now cheaper than I can do them...

Same story with Corolla 1.44 ones I made, Minisport 1.5 rollers or Minispares 1.5 forged ones are cheaper now.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:


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PostPosted: Mon Dec 17, 2012 1:38 pm 
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1360cc
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Joined: Tue Jun 01, 2004 3:41 pm
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Location: Special Tuning Sydney
If you're looking for performance gain, there are 101 things to do besides changing your rocker ratio such as exhaust, intake and extractors. Rockers are one small piece of the puzzle...

Unless you are running a big cam, big (2 inch) exhaust and intake system I'd skip the 1.5 ratios. Go with 1.3. These are the ones I (and many) are running, but many other options exist:

http://www.minisport.com/mini-spare-parts/info_MSLMS0483.html

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 Post subject:
PostPosted: Mon Dec 17, 2012 1:57 pm 
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Location: near Baulkham Hills, NSW
If you have a 1275 or bigger and you're not going to rev it over 6000, 1.3s are fine. But if you wanna use 6500 and up... go the 1.5s.:mrgreen:
[edit] depending on the cam, some cams eg RE83 are just not designed to cope with 1.5s.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:


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