Swapping CDI boxes 98/99 XC
Matt
Pretty much everyone agrees that the 98 XCs could outrun the 99 models. I
have heard this was because Polaris retarded the timing on the 99s to
increase durability. If this is true, by using a 98 CDI box on a 99 XC, the
99 should be able to outrun the 98, due to the advanced ingnition timing,
and the updated slide rail design. What do you think? any advice either
way. Thanks,
Matt in MI
Mike Luckhardt
Sounds good to me let me know how it works.
Mike
Bill S
You're on the right track about swapping CDI units, but the swap is to use
the RMK CDI in your XC, any year XC will benifit from the swap.
As far as out running a 98, I doubt it, the cylinders are a little better in
98, and the timing can be equaled by moving the stator plate.
Matt wrote in message <7k87jl$f...@journal.concentric.net>...
Matt
advanced by moving the stator, then a new CDI box won't help, will it?
Matt
Bill S <gatew...@hotmail.com> wrote in message
news:7kavcq$o66$1...@node17.cwnet.frontiernet.net...
EdC
If your friendly neighbor hood Polaris dealer is as nice as mine is to his
customers, here that Bill?, he'll show you that the timing curve is much
better for advancement then the stock XC coil is.
I think the RMK coils give an increase of 7 hp or more, also you will need
to run at least 92 octane once you make the switch.
The CDI unit has the curve in it not the stator plate, so even though you
can move the stator plate the curve of the ignition remains the same.
Does that help at all? I know if you see the curve that Polaris has listed
in its tuning manuals complete with graph you can understand it
better....you know one picture being worth a thousand words.
Matt <menge...@hotmail.com> wrote in message
news:7kb5t2$7...@journal.concentric.net...
xltboy
timing curve for 1999 700xc/ 700xcsp/ 700sks
600 rpm 6 deg
2000 rpm 6 deg
4500 rpm 12 deg
5000 rpm 17 deg
6000 rpm 19 deg
7500 rpm 16 deg
8000 rpm 15 deg
8500 rpm 11 deg
timing curve for 1999 700 rmk
500 rpm 6 deg
2700 rpm 12 deg
3500 rpm 12 deg
4800 rpm 18.5 deg
5500 rpm 23 deg
8000 rpm 16 deg
8400 rpm 15.5 deg
9000 rpm 5.5 deg
this info is from the 1999 polaris high performance manual. if you want
a graph then put the numbers in your favorite spread sheet program and
graph away.
xltboy
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Matt
have mentioned I have a 600 not a 700. Let me make sure I am understanding
this correctly, these timing curves are programmed into the CDI boxes, so by
simply switching my XC CDI with a RMK box, and running 92oct gas, that
should give me around 7hp or so?
Or do I need to switch the coils too?
Matt
xltboy <mha...@excel.net> wrote in message
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snip
EdC
What are your plans for your sled ?
Matt <menge...@hotmail.com> wrote in message
news:7kdbbh$7...@journal.concentric.net...
Matt
difference. I wouldn't do it, if it means changing CDI box, stator/coils,
among other things. I thought that maybe just swapping CDI boxes alone
would increase hp due to the better ignition timing.
Matt
EdC <em...@hotmail.com> wrote in message
news:7kddd4$1dhc$1...@node17.cwnet.frontiernet.net...
Bill S
on the XC/RMK Polaris the cdi and coil is one and the same.
the stator is not changed.
the coils/cdi units are programable, if you know of someone that is capable
of doing that for you, otherwise just buy the RMK cdi/coil unit from the
dealer.
Matt <menge...@hotmail.com> wrote in message
news:7ke4do$m...@journal.concentric.net...
xltboy
1999 600xc/ 600xcsp/ 600rmk
600 rpm 6 deg
2000 rpm 6 deg
4500 rpm 12 deg
5000 rpm 17 deg
6000 rpm 19 deg
7500 rpm 13 deg
8000 rpm 11 deg
8500 rpm 6 deg
note that in 1999 all of the xc600's uses the same cd box. it is my
opinion that switching to a 700 rmk cdi box wont get you much at wot
(8000 rpm) but i do beleive that it will help with low end acceleration
assuming that you have enough traction to keep the track from spinning.
any comments from others on this statement?
xltboy
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EdC
it helps all around, you also get to WOT faster then a stock XC cdi/coil.
At WOT, there is a 4 deg change in timing, that in the 700s' means about 5
Hp. me I'll take 5 Hp any time I can get it.
xltboy <mha...@excel.net> wrote in message
news:376B0750...@excel.net...
xltboy
with excel using the data i have. if i owned a xc600 and was thinking
about changing to a 700 rmk cdi box i would first change the timing of
the stock setup by 4 deg. if you plot the data polaris supplies for the
xc600 and 700rmk boxes you will notice that the profile of the curves
are very close. now if you add 4 deg to the xc600 plot you will see that
the two curves are almost on top of each other with the exception of
rpm's below 2000 rpm. i beleive that this is why edc says the change
will help all around performance and after looking at the info again i
would agree with him.
EdC
Why don't you go and try futzing around in the shop on a real sled and motor
where most real mechanics do ?
I tried it against the clocks and against other 700s' and it works a lot
better then on paper.
There are always things that look good on paper but when tried in the real
world don't hold up.
Advancing the ignition curve on the stator alone will not work, I tried
that.
The box expects to see so many impulses per second.
xltboy <mha...@excel.net> wrote in message
news:376C62CD...@excel.net...
Doug Miller
>Gee you did some futzing around on a computer program?
Hey, looks like all of us are futzing around on a newsgroup.
>Why don't you go and try futzing around in the shop on a real sled and motor
>where most real mechanics do ?
I guess I ain't a real mechanic. The guy spent some time comparing two
timing curves. If he got it wrong, or made a mistake, I think he's
open to being shown where he went wrong.
But it looks to me like he is trying to understand why a guy can't
just advance the timing 4 degrees and pick up some ponies.
Kind of like the y2k rmks are going to do from the factory.
>Advancing the ignition curve on the stator alone will not work, I tried
>that.
>The box expects to see so many impulses per second.
On to new topics.
Moving the stator, or the timing, will NOT change the "impulses per
second".
-doug miller