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Discussion Starter #1
I am running a black ice 46 deg cam in my mach z. It is on the a-6 setting. If I put it on the a-5 setting what can I expect to happen. Right now I run it on clicker position #2 and I turns 8400-8500 rpm. If I put it on a-5 will it shift out faster on top end or load the motor down in the low end. I am looking for set up for the road or lake. My frinends t-cat would pull on me on the top end on my old set up.

Thanks
Duane
 

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A-6 is about 18.5# if you go to A-5 is 23#, you will slow down the up shift making the engine rev higher you will also be putting excess side presure on the belt. A-6 is a good, you shouldent need much more then that.
 

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Discussion Starter #3
I just looked at the spring chart on the first page and saw the pressures. I was wanting it to shift out faster so if I go to 16.5 lbs will that shift out faster or is that not enuff belt pressure.

Duane
 

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unless you have pipes,regardless of year,try turning the engine at 8000 rpm all the way through,if it is a 98 turn it 7800,either way on a stock motor your are throwing away at least 10 hp and a pile of torque past 8100.Dont take my word for it just try it youll be impressed.
 

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Sorry,also try to run your secondary at 16 lbs.Im not too familure with those helixs,and from what i have seen no one is really sure what skidoo numbers are in relation to hrps,We run either a straight 52 or 54 48 helix in our mach zs and they pull real well all the way through.Again this advice only applies to stock piped motors.
 

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from my experience with a 44 deg BI helix in my 96 F3, I would say that your 46 BI is equal to a normal SD 52 deg helix.
 

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John what kind of top end speed are you getting running the low RPM.
I have 2 buddys that ride machz's a 98 and 99 both with goodwin kits and they are set-up to turn 8000rpm. The 98 is a rocket and the 99 is a bit of a dog.
 

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Discussion Starter #8
I also have a set of pipes off of a 99. I want to try them this winter after I get this set up tuned in right. As soon as the ice is good I will be doing some testing at my friends lake.

Duane
 

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670,last winter it ran 112 mph in 1000 feet.Currently I havent got enough helix and weights to keep it under 8000 after 800 feet.It jumps out to7700 and slowlly creeps up to 8000 even with 27-43 gears.I started out with clickers on 4 and 8000 rpm ,each time i dropped a clicker position it picked up top end.With the mods that I have done and the stock 98 pipes its suppose to max out at 7800 rpm.Problem is when you drop spring tension,raise weights, or put in enough helix to load the motor,it gets real weak on the back shift.From a dead stop it will run and hide from my buddies zr 800,but come out of a corner from a rolling start and it takes me 1000 feet to real him in.This year Im going with a set of trail pipes and see if i cant make it work the same or better at around 8400 rpm,might just back shift better with lighter arms,and more spring tension.(never had it on radar wound out fully,but will put the needle past 120mph no problem,not too sure how accurate the speedo is though)
 

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If I can ever figure out how to use my scanner i have 3 or 4 differnt dyno sheets for the 98,stock,trail pipes,etc.Untill i tried it myself on radar I would not have believed how low of an rpm those pipes really like to turn kind of like an mxz 670 with another pipe and clyinder.From what I have seen clutching mach z s is most guys turn them 2 to 300 rpm too high through the mid range those rpms above 8000 would be good if you were geared for a specific distance and you hit those revs just before the finsh line.
 

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So far with my experiences in tuning the secondary I have found a high spring tention like 25+pounds works excellent. Keeps the belt slippage to a bare minium [little clutch heat] and good back shifting, this is with stock spring and 53/47 helix. I blew belts all the time with 16-21# of tention especially at high speeds. It now accellerates awsome and back shifts real good too.
Dyno sheets are ok and gives you an idea where to start but the real world is on the snow.
Remember, if your clutches are to hot to touch you got a lot of slippage going on and a higher tention can usually remedy the problem.
 
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