R/C Tech Forums

R/C Tech Forums (https://www.rctech.net/forum/)
-   Electric On-Road (https://www.rctech.net/forum/electric-road-2/)
-   -   Pro 4 Still Competitive? (https://www.rctech.net/forum/electric-road/295549-pro-4-still-competitive.html)

Twism86 05-08-2009 06:04 AM

Pro 4 Still Competitive?
 
Hey

I have a HPI Pro 4 and am looking to get back into racing. Probably will run a 17.5/27T stock class and then move to 13.5 SS.

Do you think my Pro 4 will still be able to keep up with all the belt cars today? I know a lot has to do with the driver obviously, but all things being equal whats your opinion?

The real queation i guess is will buying a belt car give me an advantage over using my Pro 4. I cant afford a fancy new one but may buy a used 415 MSXX. Does anyone one think thats worth it?

Thanks,
Tom

jhwnissan 05-08-2009 06:10 AM

I don't think it would be worth it to you to just go out and buy a new one. I race street weapons still and they are just as competitive now as they ever were in the stock class. Ya really gotta weigh your familiarity with the car and your driving style. I still prefer my old school touring car because it matches my style. I don't think anything would really be that much of a disadvantage in a stock class and I think when you go to move up, you should be just fine especially with the great equalizer.... the brushless, lipo setup. It seems to breathe new life into most older cars from what I hear. If you can still get parts, keep what ya got. Newer aint always better.

rcterp 05-08-2009 06:12 AM


Originally Posted by Twism86 (Post 5785928)
Hey

I have a HPI Pro 4 and am looking to get back into racing. Probably will run a 17.5/27T stock class and then move to 13.5 SS.

Do you think my Pro 4 will still be able to keep up with all the belt cars today? I know a lot has to do with the driver obviously, but all things being equal whats your opinion?

The real queation i guess is will buying a belt car give me an advantage over using my Pro 4. I cant afford a fancy new one but may buy a used 415 MSXX. Does anyone one think thats worth it?

Thanks,
Tom

Great car, still very competitive. Especially in stock racing (shaft drive is very efficient). Make sure you get good equipment for it and when and if you upgrade car's you'll already be ahead of the curve.

Skitee 05-08-2009 06:13 AM

The PRO4 is definately still a very competitive car in 17.5/27t and 13.5/19t. We still have a couple running at our club and they are right up there with the latest and greatest touring cars.

or8ital 05-08-2009 06:13 AM


Originally Posted by Twism86 (Post 5785928)
Hey

I have a HPI Pro 4 and am looking to get back into racing. Probably will run a 17.5/27T stock class and then move to 13.5 SS.

Do you think my Pro 4 will still be able to keep up with all the belt cars today? I know a lot has to do with the driver obviously, but all things being equal whats your opinion?

The real queation i guess is will buying a belt car give me an advantage over using my Pro 4. I cant afford a fancy new one but may buy a used 415 MSXX. Does anyone one think thats worth it?

Thanks,
Tom

Some people feel that shaft drive cars are faster in a 17.5 class and with brushless motors torque steer really isn't a problem anymore. So I would stock with the Pro4.

Twism86 05-08-2009 06:23 AM

Just found out i will be running 13.5...

Thanks. I wonder what makes torque steer not a problem with lipo?

Ive never run BL before so can anyone recommend a good gearing to start with for 99/100 tooth pinion (64 pitch) with a 13.5 motor.

I guess my best plan is to get my BL setup and lipos, start racing and then see where im at. Thanks!

rcterp 05-08-2009 06:26 AM


Originally Posted by Twism86 (Post 5785978)
Thanks. I wonder what makes torque steer not a problem with lipo?

Ive never run BL before so can anyone recommend a good gearing to start with for 99/100 tooth pinion (64 pitch) with a 13.5 motor.

I guess my best plan is to get my BL setup and lipos, start racing and then see where im at. Thanks!

Torque steer was mainly a problem with the armature of the brushed motor. With brushless that problem is greatly reduced.

Gearing is tough now with different timing options on ESCs. Most people start around 4.6 and go from there with a 13.5.

Twism86 05-08-2009 06:32 AM


Originally Posted by rcterp (Post 5785983)
Torque steer was mainly a problem with the armature of the brushed motor. With brushless that problem is greatly reduced.

Gearing is tough now with different timing options on ESCs. Most people start around 4.6 and go from there with a 13.5.

Thanks. Do you know what pinion size that matched up with? My gearing chart doesnt do to 4.6 (isnt made for BL).

Or an can anyone recommend a few pinion sizes to get that i can play with.

All help is very much appreciated, thanks!!

akimoto 05-08-2009 06:49 AM

what do u have now ?

Twism86 05-08-2009 06:54 AM


Originally Posted by akimoto (Post 5786051)
what do u have now ?

I have a pro4 now. I dont think its a special driver edition. I just havent raced in in maybe 2-3 years.

SammyZ 05-08-2009 07:02 AM


Originally Posted by rcterp (Post 5785950)
Great car, still very competitive. Especially in stock racing (shaft drive is very efficient). Make sure you get good equipment for it and when and if you upgrade car's you'll already be ahead of the curve.

+1

akimoto 05-08-2009 07:04 AM

ok,
i'm talking abouth pinion, spur ......... al my electric 1:10 are pro 4
what are u lookin to run
i was comprtitiv with 19 T brush & LIPO,if u whant to run BL u have to up-gear motor pinion and down gear the spur

RC-DriftNewb 05-08-2009 07:10 AM

I'm running a Pro 4 Myself in stock class and doing well. First day out for the season I took TQ and finished second in the main. Hoping for a first place finish this Sunday. :)

Torque steer isnt as big of an issue with the BL motors. Lipo wont make any difference. The reason is brushed motors have a lot of RPM. So the armature of the motor was spinning very fast and had a lot of inertia(lots of mass) while the driveshaft and transmissions were spinning slow with not nearly the same rotating mass. But now with BL motors the RPM's arent even close to what the brushed motors are. They're very very close to one another so torque steer isnt a problem. At least thats how I see it.

I love the pro4. And when its set up right its a tough car to beat. Just keep the bearings cleaned, the diffs and gears shimmed right, and you'll be set! I cant wait to get out there this sunday and beat some TC5's, Xrays, and other cars. :sneaky:

or8ital 05-08-2009 07:27 AM


Originally Posted by RC-DriftNewb (Post 5786135)

Torque steer isnt as big of an issue with the BL motors. Lipo wont make any difference. The reason is brushed motors have a lot of RPM. So the armature of the motor was spinning very fast and had a lot of inertia(lots of mass) while the driveshaft and transmissions were spinning slow with not nearly the same rotating mass. But now with BL motors the RPM's arent even close to what the brushed motors are. They're very very close to one another so torque steer isnt a problem. At least thats how I see it.

Actually I think its more the size of the rotating mass being about half the size that causes it to not be as big an issue. A brushed arm is a lot bigger then a brushless arm.

RC-DriftNewb 05-08-2009 07:43 AM

That would play a role too because it would have a larger rotational mass compared to the dirveshaft of the car. The more RPM and mass the more its going to counteract the lightweight low rpm driveshaft. In the end its all the same thing. :)


All times are GMT -7. It is currently 06:00 AM.

Powered By: vBulletin v3.9.3.8
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.