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Getting a TOP CAT to steer.

Posted: Thu Dec 24, 2009 10:55 pm
by Bormac
Ive been trying to drive around the problem of a Topcat's inability to steer through tight sections of the race track. I had tried tyres, extra toe out and a narrower front end, the steering mod kit and a couple of other things but nothing made the difference like changing the rear arms. Forget the kit items and WORKS rear arms were not the answer either.
I cant remember the part number but next time I clean my car I'll update this post with the appropraite details.

My last ditch efforts saw me mount the option heavy duty rear sway bar, reposition the battery from a stick running up the centre to saddle packs at where you see them here now. I reduced the droop in the rear also. Now this thing turns on a dime! The last meeting I drove it at I ran of all things radius ribs up front and Bow Ties on the rear. The car drove realy well and I was shocked that i finaly got this car to turn. Obviously shortening the cars wheel base made the biggest difference but there were plenty of changes made in the end and it all seemed to work. There was quite a turn out for the sealed can 540 class and there was for the first time an A and B final. The Topcat netted me 3rd in the A's against far more accomplished drivers than myself driving Losi JRX PRO's and PRO se cars amongst others.

Not bad for a Topcat :wink: :mrgreen:

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Re: Getting a TOP CAT to steer.

Posted: Fri Dec 25, 2009 7:39 am
by RedScampi
Nice pics! It's good to see a dirty rc car around here! I'll be sure to refer to this thread if I ever actually drive mine! :lol:

Re: Getting a TOP CAT to steer.

Posted: Fri Dec 25, 2009 12:43 pm
by Jay Dub
Ah, I love the old top cats. I never had one, as I started driving for shumacher when they came out with the next version car, but I always wanted one. But I do remember that the cars I originally had also had steering issues. I tried a million things on the car, and eventually started disecting other competative cars looking for answers. Eventually I figured out that weight distribution was the biggest culprit. I weighed the front to rear bias on my RC10 (which at the time was the benchmark for competitive 2wd buggies), and found that the schumacher cars were an ounce plus light on the front end. After adding an ounce of lead to the front, the cars were a 1000x better. I think that you are underestimating the weight distribution change you made, and it is propably the BIGGEST change you can make. I remember adding a 1/4 ounce to the front of my rc10 to add/remove steering. So an entire ounce was huge! Eventually I made it part of my setup on a new car build. Before I took a new kit to the track, I would weigh the car fore and aft, and add lead as necessary to find the distribution I always ran. It saved alot of time at the track tuning. -Jeff

Re: Getting a TOP CAT to steer.

Posted: Sat Dec 26, 2009 10:39 am
by 8rad
Thanks Jason. Great pics. Very helpful. I will experiment with different setups in the spring. There is a foot of snow on th ground here so no more racing this year. :cry: :cry: :cry:

Re: Getting a TOP CAT to steer.

Posted: Sat Dec 26, 2009 3:07 pm
by top cat mike
Great job as always. I think u underestimate your abilities by calling the other drivers more accomplished. If there is a Top Cat expert you would be he

Re: Getting a TOP CAT to steer.

Posted: Sat Dec 26, 2009 5:07 pm
by Bormac
top cat mike wrote:Great job as always. I think u underestimate your abilities by calling the other drivers more accomplished. If there is a Top Cat expert you would be he
Mike you are far too kind. :mrgreen: What I meant to say was that I barely drive any 2WD buggies throughout the rest of the year so for me to do well with a Topcat against regular club and state racers who are accomplished modern day 2WD racers is a feat in itself.

Re: Getting a TOP CAT to steer.

Posted: Sat Dec 26, 2009 9:51 pm
by Mad Racer
Jason.

Your efforts has been paid off. Your prep work is second to none.
As with all old vintage buggies they had some handling problems ( not rc 10 or losi ) as i have the same problems with my cars.

Your perseverance has really paid off. I think the weight balance is so criticle to get right. A SWB will help just as much as you are changing the weight distribution is changed as well.

Cant wait to race my Frog against your top cat. :lol: :lol:

Re: Getting a TOP CAT to steer.

Posted: Sun Dec 27, 2009 6:40 am
by peuge73
I remember a french article of an international race in 2009.
The author was desapointed regarding Top Cat racer's perf. Due to a front lazy behaviour, schumacher team was a bit late in 2WD.
The only solution was to fit a RC10 front end to the top cat in order to manage the fast bumpy track.
This was of course just before Cougar creation.

I think that racing against losi like JRX pro and Pro SE with your Top Cat was really a hard challenge !!!

Congratulation for this (succesfull) revival!

Re: Getting a TOP CAT to steer.

Posted: Sun Dec 27, 2009 7:32 am
by Bormac
The author was desapointed regarding Top Cat racer's perf. Due to a front lazy behaviour,
Yeah no doubt the Topcat's front suspension is not the cars strongest atribute. Personaly I think its the 'ratio' of the rocker arms that make for a weak front end when it comes to bumpy tracks and lots of jumps. They tried beafing up the rockers aswell to counteract the heavier springs rates (my guess) that people would use but this never fixed the problem. I think with a better 'ratio' of rocker the car would hold up better, Kind of like the REVO set up.