1000 T-cat clutching???

[Phat Cat]

Hi, I am running a 1000 t-cat ported, 1107 D&D pipes, 38mm carb rack bored to 39.5, etc. Dropped & rolled chain case, 156 X 2.5" X 15 wide track. My clutching worked great with a 144 and 151" X 2" track but now I need to change some clutching. I loose RPM on long climbs. The initial RPM is perfect at 8500 but then it drops to about 8000 and I loose alot of track speed. My set up right now is:
170 - 300 Black & Purple Black Magic primary spring
64 gram weights
56 / 40 Helix
Green sno pro secondary spring.

I am hoping to just change out my helix but I would be willing to change out the entire setup if anyone knows what would work well in my sled.

Any help would be great!!
Thanks

 

[longhairfreak]

Im not sure if you noticed but Cat has gone to much shallower helixes. Why do you think they do that? Because it works better. But remember as you go shallower in the helix youll have to increase the weight in your primary.

 

[Phat Cat]

Yes I am going to try a shallower helix. I will have to take a day to test out different clutching. Anyone have a sled like mine with clutching that works well or any usefull advice?

 

[longhairfreak]

Good luck with that.

 

[Phat Cat]

Thanks!

 

[rdr99]

The 156x2.5 track is heavier and much more aggressive than the 144 or 151 that you ran previously. I think I would try gearing down a little.

 

[rdr99]

Saw in your other post that you are at 19/43 gearing. That is plenty. Maybe try a 49 or 51 helix.

 

[HANDSOME]

Try a straight 53 helix with the sno pro spring and I would try a holeshot orange in the primary. I think 64 grams may be a little heavy .

 

[HANDSOME]

Also put the stock pipes back on or tighten up those stingers.

 

[Phat Cat]

Yes I have the 19 / 43 gearing. 8 tooth 3 pitch drivers. I have tries PSI and Jaws pipes on my sled. The 1107 D&D pipes work alot better on a ported 1000 motor. When I changed pipes to the 1107 I had to jet up and add 2 grams to the weights. That tells me I am making more power with these pipes. I could also feel the difference. I am reving right at 8500 RPM which was suggested and the dyno shows that I don't start loosing HP until 8800 RPM.
Thanks for all the suggestions. I will try some different helixes and secondary springs.

 

[Thunder101]

Im not sure if you noticed but Cat has gone to much shallower helixes. Why do you think they do that? Because it works better. But remember as you go shallower in the helix youll have to increase the weight in your primary.

Did they not do that because the sec is SO diff from the chain case days ?

 

[Thunder101]

are you running 38 carbs ? that 40 finnish angle on the helix is pretty crazy,
What elevation are you at ? and it would not hurt to measure the stinger size on the 1107 pipes, egts?. What kind of porting ? transfers touched ? case must be done, right. if you had it on a dyno what hp # did you make.
I have a Tcat everyone talks trash about how heavy they are but I think they pull like a Mother F_cker.

 

[Phat Cat]

Hey Thunder101,
The crank went out on me about 5 years ago. When I rebuilt it, I took it in to Echo Cycle in Edmonton and had the top case half ported (widened) They matched the cylinders to the case, and mild transfer port work. The guy who ported it had lots of experience and did alot of t-cat motors. I had my 38 mm flatslide rack bored to 39.5mm. At the time I was using PSI pipes and was dynoed at 204 hp. I was pretty happy with that. I am using a Black Magic mono block head with lake race inserts that are good for 91 octane at sea level. I have a PSI dial a dome head I might put on.
I am at work for another week and I will measure the stinger ID when I get home. I try to run my egts 1200 to 1250 with the probes 4" from the piston skirt.
Ya I have heard my share about my thunderpig. When I had my 98 chassis it was a heavy pig. After I build my chassis in 2001 it wieghed 520 lb dry. I have not heard to much trash about my heavy t-cat lately. I always say bring it, dont sing it!! lol.
About the helix, I think I will run a 52 / 44 progresive. It wont hurt to try it.
Thanks for your input.

 

[luv2ride]

im running the same primery set up as you but a 49 with red white in secondary it works pretty good and holds rpm

 

[longhairfreak]

Did they not do that because the sec is SO diff from the chain case days ?

No they did it because it works better. Polaris has been running shallow angles for years. I used to run a 42 degree with the red white spring just add the weight you need to hold rpm and your done.