Brushless into Old Skool Models

[rasher]

Just after some advice from you guys who have converted your vintage runners to brushless.

Looking at dropping a Brushless Setup into my vintage XX4 for the A1 Iconic. Just about solved the Lipo Pack installation....(got a bit of carbon work to do).... but not sure about motors. I used to run 11T or 12T Doubles at the back end of the 90's but don't really know which brushless motor winding would equate to the same kind of RPM.

I have a 6.5T I can drop into the chassis but thinking it may be a bit hot! Don't really want to tear the old girl apart at the seams!

I was thinking maybe an 8.5T or 9.5T may be a bit more suitable..... especially seeing as I haven't raced for a few years now.

Anyone have any kind of advice on old windings compared to new windings and RPM?

Cheers.

[StuartH]

After getting back into things with a 13.5t rtr model I put a 10.5t motor in my schumacher cougar 2000. It's more than enough for it. I am finding that going any hotter tends to throw up all the handling deficiencies in the older cars.

They just don't corner or handle the bumps as well.

[Peakey]

That really comes down to setup Derbydan is running a 6.5t in his Procat with good results. I'm not sure what I'll be running yet but I would of thought it is going to be around that.

[OptimaFan]

Apart from the possibly less handling, which at least partially comes from the shorter A-arms on older cars vs new ones, if you ask me, many vintage cars don't come with a really strong slipper clutch, if there is anything like it installed anyway. But indeed handling is also part of the setup, a well setup vintage can still handle better than a less optimal setup modern car. Maybe the older cars are less forgiving when it comes to shock setup, due to the lower leverage of the shorter A-arms. Also probably matters if you stay 2.0 inch with the wheels, or 2.2 inch, which roll over bumps just that bit more easily.

My advice, based upon what I've seen others running in their vintage cars, would be to stay above 10T (actually a 10T motor would be a little less powerful than a 10.5T, as a 10T is a 380 size motor in 540 size can) and maybe also lower the punch setting on the ESC, so the motor starts a little softer than it is capable off.

[Welshy40]

I think youd be better of with an 8.5, 9.5 or 10.5

Yes i use a 4.5 in my vintage but its a bit special and has tensioners on the belts which aides it in handling the power. Handling well i made tenth in the Maritime series championship so shows that newer doesnt always mean better. Slipper yes youll need to upgrade but wouldnt parts from the new 4wd fit seeing as they have basically taken the xx4 drivetrain and upgraded it?

[Frecklychimp]

XX4 is still a very competitive car against the modern models, last years National series results proves that one!

They will take modern 5.5T/6.5T power but i know the team were struggling with eating slipper plates quickly when running XX4's last year and they are hard to get hold of new these days.

personally i'd go for a 8.5T and run boost as needed for top end, it'll be a bit softer lower down which will help the slipper and will still be a lot quicker than a vintage brushed set up ever was.

belts also have a hard time with brushless, with expansion under power and slipping under harder braking so its best to retro fit tensioners and use Tough Racing kevlar belts where possible, i know this is the case with CAT 2000's too.

Older cars are a lot lighter so if you stick to power to weight thinking and don't go for silly tyre shredding fast in a straight line power you won't find yourself adding loads of weight to balance handling so will have less strain on transmission.

It seems these days in comparison we have a lot more downforce (which effectively adds weight) add lots of brass bits for balance and then add loads more power to compensate, back in the day we were trying to make cars as light as possible to limits.

I'm running a 10.5T with no timing in my XX and its as quick as my Vega running 7.5T and boost and keeps up well with modern cars on track, obviously the handling is not as sharp over the obstacles and jumps but XX is a lot more fun to drive, needs a few tweaks to adapt to astro grip levels better but its definitely brought more of the enjoyment factor to racing back.

[rasher]

Guys....

Thanks for all the feedback.... some great advice for a complete newbie to brushless.

I will most likely go with an 8.5T, soften the lower end and gear it in the lower half of the recommended ratio range for the motor. As long as I still get some good 'pop' for the jumps etc and some good straight line speed I'll be more than happy. It's not a WE XX4, just a stock 97' model so it's not the toughest chassis these days.

I did look at the Losi 22-4 Drivetrain....it all looks very similar but just isn't the same. I think I'm right in saying that the 22-4 has actually gone metric....and for definate...the drive belts are longer on the new model. Shame that....would have been great for keeping the XX4's around for a long while yet.

I keep looking out for an old XX.....I had a short spell with one back in the day. I do enjoy 2WD aswell but no where near as much as 4WD...

Looking forward to seeing the Schumacher' s and Kyosho's at the A1 Iconic, especially with some of the modern tweaks a lot of you have engineered...... I was too young to afford anything as classy as that when they were in their prime... just used to drool over them.... it all started properly for me with the Losi in the mid 90's which I thought was a great era of RC Offroad.....we even had summers!

Anyway..... I digress ...... thanks for the advice again everyone. Looking forward to the 27th!

Ian