JDM_DOHC_SiR

iTrader: (31)

I`ll post some pic`s of it ..it`s much easier to do it that way I have way too much stuff on it to list

-Dave

JDM_DOHC_SiR

iTrader: (31)

OK Pops` I now just figured out what your talking about
-Dave

popsracer

JDM_DOHC_SiR;
We'll leave it at that.

I do really think there is something to be gained by relaxing the tension on the Long belt. I "Pinched" it between my fingers to stretch it and the Drivetrain spun easier/longer. Only thing is after a minute or two it was tight again. Just have to order another belt and try the WD-40 and Weight thingy.

newracer

I agree the car would greatly benefit form a loose front belt, I just don't know what the best method of stretching one is?

Frank McKinney

What we've done to increase efficiency is Dremel the bearing cutouts in the front bulkhead so the diff is moved back about 1mm-1.5mm. This dramatically loosens the front belt.

Another thing Thad is doing is adjusting the hingepin spacers so the CVDs are coming as straight as possible out of the diff outdrives, so there is as little rubbing as possible.

A fully freed-up Pro 3 will run very efficiently, don't forget to do all the normal bearing tricks (degrease them and use light oil, remove the shields, etc.) if you want to go all out. Just remember your bearing life will suffer significantly.

newracer

I guess that means that not even HPI employees have found belts that are loose when new.

I remember seeing a link to a company that sells belts wholesale, I wonder if you can get one just a litle longer.

popsracer

Frank McKinney;

Hey Frank, thanks for the Ideas. I think that I'm going to try them both.

I've been doing very well with my Pro-3 locally in Stock class and I think that if I can free-up the drivetrain a little more, I'll be able to kick some serious B__T.

Thanks, again!

Frank McKinney

Actually it's more efficient to just Dremel out the bulkhead - we didn't have to sort through tons of belts or special order expensive new belts, etc. We can simply use the same belts we've been using and when it wears out replace it with the same part number.

popsracer - good luck racing! Hope the tip helps.

sosidge

I do think the answer would have been an extra tooth or two in the front belt, maybe it should have been done at the same time as the wishbones and outdrives - bit late for that now though!.

popsracer

Guys;

Upon closer examination, there is only about 0.5mm between the Steering and Diff Pulley Now as it is. So I'm not going to risk Dremeling the Front Bulkheads and having the Diff rub.

Guess I'll try some WD-40 and see if that helps any.

As for HPI using a longer belt to begin with. I believe that most R/C Car companies do not manufacture their own Belts, but purchase's them from another company that specializes in small timing Belts.
Usually unless they spend Mega $$ on a custom one of size belt, they are only availible in certain sizes from the manufacturer and the next size up or down will be more than just a couple of teeth.

JDM_DOHC_SiR

iTrader: (31)

Well I just got thought letting the belt stretch for 2 days I can say this it is a bit looser......... but not as loose as I would like it to be......don`t get me wrong..it does make a slight differance I`ll have to take a picture of before and after with a new belt so you all can see the differance in how much it has been lossened up also I`m going to try franks ideas too

-Dave

Downforce

It's too bad the front bulkhead doesn't have the cam action like the rear. I may try Franks idea.

-Derek

yobbism

iTrader: (3)

i think i will get the dremel out this weekend too and take a bit out of the front bulkhead. thanks!

have use improvised anything for the diff outdrives, instead of the little 'rings' to keep them from flexing and breaking (or throwing a cvd bone)? an easy way to solve it is to make a sleevewith about 3mm holes drilled for the pins on the CVD bone to go through. the pins hold the sleeve on but the 3mm holes let it move enough for shock travel.
any thoughts?

sosidge

I think the updated rings (wider, with slots) are good enough already. They don't limit the bones movement and they keep the outdrives in shape.

popsracer

Guys;

I'd be very careful if you Dremel the Front Bulkheads. There's not much room as it is for the Steering to clear the Diff. Go too far and the diff will rub, negating anything you were trying to achieve.

I'm not even willing to try it and consider myself an Expert with the Dremel.

What the Pro-3 needs is Outdrive Savers like you can get for the Losi's. An Aluminum Collar that slips over the outdrives to keep them from breaking/spreading.
(Machinist's out there: Hint, Hint!)