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PostPosted: Sun Apr 01, 2012 8:41 pm 
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Location: near Baulkham Hills, NSW
Cuts wrote:
My mini since doing the dizzy swap is all sorts of hating life. It runs but poorly, might need to replace the cap and rotor button.
I've not driven mine yet but I suspect it to be a very low performance engine haha.

They work in a Mini if you just bolt them in, but-
Did you modify the advance curve? Most Pulsars have about 15° centrifugal advance in them (15 dizzy °, = 30 crank °). This means if you set the total advance to the typical 30° BTDC at 4000rpm or so, you have ZERO static advance. = Poor low speed and midrange performance.
If you set the static advance at 5 or 10°, you then have too much total advance = you can burn pistons etc.
In most modified Minis you need to shorten the 2 slots in the advance plate to get around 10° max advance in the dizzy, read back a bit in this thread. :wink:

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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: Thu Jan 31, 2019 10:48 am 
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Joined: Wed Oct 22, 2008 5:06 pm
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Location: Coffs Harbour
Hey Guys

I know this is an old thread but thought I would add some info, could be useful.
With the Hitachi D4R Dizzy, the number after the R is just the build year. ie D4R85-16 = 1985. D4R83 = 1983. This number has nothing to do with if it is fitted to a manual or auto. The last number is the vac advance spec but it is not in degrees. for D4R85-16 the 16 is vac advance graph number 16.
The mechanical advance was changed through the years so an 83 may have a different advance graph/map to an 85.
I am running a D4R85-16 in my SC12 supercharged 1966 1275 (with MSD boost retard). Mech advance is as per prev mentioned in this thread. I am at the moment setting up a D4R80-11 (JDM spec i think) in a 1968 1275 and it has factory mech advance figures of:
start @ 700rpm (dizzy rpm)
all in @ 2700rpm (dizzy rpm)
max advance 12.5deg.
I will be leaving the max as is but obviously removing a spring or springs to get all in earlier.
From the looks of it, most of these D4Rs have a very gradual advance curve, most of them are not all in until at least 2,500 dizzy rpm (5,000 engine rpm)

http://newprotest.org/projects/510/dizzy_specs.htm

Edit. It appears as though judging by the above link. The final two numbers may also represent a model number that has unique mechanical and vacuum advance. For example a D4R82 seems to come with 3 different mach advance profiles

cheers
Rick

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