Stock Motor, Gearing Questions for FT T4

[Bugs Buggy]

There have been a lot of posts having to do with stock motors, but I'm still a little confused... :rolleyes:

I have a Factory Team T4 and I've tried a variety of Stock motors in it and just can't seem to find the right combo. It's not that the truck performs bad, it just doesn't quite have the acceleration off the corners and the top end speed some of the really fast guys' trucks have. The track I go to has medium to high traction, a medium short straight (it takes roughly 2.5 seconds for a stock truck to clear the straight), and various jump patterns throughout the year. I use GP3300 and GP3700 cells and use comparable tire settings to the competition....

I have tried the following:

-Trinity Monster PRO, Spur 87, Pinion 18, Novak GTX set to preset 2:

This netted me the highest top speed, but the truck felt 'heavy' (for lack of a better word). Simply didn't have enough torque to get over some of the jumps..It works very well with my buggy, though :)

-Trinity P2K2 PRO, Spur 87, Pinion 19, Novak GTX set to 2 or 3 depending on track conditions.

This had better torque than the Monster by far (the best of the bunch), and didn't go that much slower in the straight (although it was slower..)... However toward the end of the run, the truck starts to labor over the jumps a little, and I would like a little more torque to play with (could still feel a little "heavy")..

-"AfterMarket P2K2 derivative", Same setup as P2K2 above

This had a little more top speed (RPM) than the the Trinity P2K2 Pro motor, but the torque was dissapointing..my Monster HP had better torque than this!! Perhaps this motor was just a dud.. I have a Green Machine Derivative for my Buggy (same manufacturer) and it rips!

-Trinity P2K Pro Motor, Spur 87, Pinion 20, Novak GTX set to 2 or 3 depending on track conditions.

This had a little less torque than the Trinity P2K2, but it hits much sooner in the RPM curve. I was able to get over the jumps fine until about 4 minutes into a 5 minute race, then it gets a little sketchy.. If I go to a 19 tooth pinion, the truck wants to spin the tires a bit too much..not to mention, the straightaway speed is lower than the other motors. I can accelerate fairly well with this motor (which I like), but it runs out of steam towards the end of the straight and the other guys catch up to me..


So at this point I'm not sure if I should go down on pinion size and get a high RPM, medium to high torque motor, or go high on the pinion and get something with Stump pulling torque and lower RPM.

I'm finding there's a fine line between good power and excessive wheelspin :D Any Suggestions???


:cool:

Bugs

PS, Lets not talk about my driving rearding this subject and stick with hte technical side... that topic is AHEM! :eek: another subject alltogether... :D

[freemachinist]

I hate to say this, but...go brushless. Also all of the motors you mentioned i didn't think they were "stockers". But also when you change motors and gearing you really do significantly change how it drives. So your driving style may infact be the culprit. When I installed my high zoot Reedy motor it was like I had a whole new truck. I was crashing all over, missing landings, you get the picture. If you can afford it get another T4 and set it up similarly, take'em to the track and see how certain options work. With all my friends, I sacrafice top speed for torque. They can not line up for jumps as well as me, as long as I'm clean thru the jumps it doesn't matter how fast they can go, they just keep crashing by using the "full throttle" approach. I'm sure this didn't help you at all...over all if you like the 87 spur, just keep changing the pinion by a tooth or 2 till you achieve the torque and acceleration you can live with.

[gizmoguy303]

I race stock with a T4 so I think I can help you. When running a Monster I usually use a 17 or even a 16 tooth pinion. I run the #3 profile on my GTX. With the P2K2 I'd start at 18. Another reason you may not be as fast as the other guys is your batteries. Top-notch batteries are definitely needed if you're running in a competitive stock class. Keep us updated!

[Kaotic]

i'm running the Monster pro 18/87 GTS esc, SMC IB 3800 Economy ($48 ones)-and i'm having the same problem w/ torque. I was thinking it must be the batteries, what would be a good top notcher for us to buy???

[nicholcgn]

Ok,

The other thing to consider is are you doing the same motor maintenance and tweaking as the top guys. There is brush hood alignment. Turning comms, Brush \ Spring combinations. How long has the motor you have been on a shelf and in your possesion. You may need to have the can zapped. If you are friends with a fast guy ask him to help tune your motor. Also maybe have him drive your truck. It may be he has much more corner speed. Thus his motor will seem to outclass you. Have him compare his truck against someone and your truck against the same truck.(I know kinda driving but then again I do not want you dumping money on $100 pack and
your actual vehicle is right up there.)

A friend of mine got into motor tuning and tuned one for me and all I can say is 10% plus increase. The deal is it will only last 1 weekend and starts trailing
off. I have the comm turned more often which is better than less often.

If you add this to a REASONABLE(World level batteries are not needed by most.) set of batteries then you should be ok.

Also I did not see mention of Charging rate comparisons and battery maintenance. There are tricks that they may be doing to get that little extra.
They may charge a higher amps than you. They may be dead shorting their cells. In stock this can change things. It also can cost more money in the short and long term. THey may also be doing care that keeps their batteries
in peak condition.

Also on the excessive wheel spin - Are your tires in the same condition as the fast guys. If you are running holeshots for the 5th weekend of racing and they are swapping every other weekend you will have different traction than them. Maybe even excessive wheel spin.

[Kaotic]

where would be a good place to start learning how to tune motors?

also what are some good name brand batteries, and which ones should I buy?

Thanks

[Bugs Buggy]

Well, I just put my P2K2 back in and put an 18 tooth pinion on it.. We'll see if that makes a difference in acceleration without sacraficing straightaway speed.

I race on Friday, so I'll report on how it goes...

I use Fusion V2 battey packs, 3300s and 3700s with 1.180+ average voltages...

I do charge them in an unordinary fasion due to time constraints.. Since I work all day and have to race at night, I can't completely charge the packs right before a race.. Instead I discharge and equalize them, then fully charge them the night prior to the race... then I top them off right before I run..

This may cause the packs to run a little flat I guess, but since I don't have 2 chargers yet I can't see where I can fit a full charge in on race night (my packs take around 45 minutes or more to charge at 5amps and many times I don't get that much time between heats...).

The thought of different brush springs came to mind after I wrote the first post..

Does anyone here use different springs than the stock ones?? Do you use firmer springs for more torque?



I have looked at brushless motors for use in modified racing... I'll probably upgrade to that as the next hop up. I do have a Cobalt 10x2 motor that I've used in my T4, and I either spin the tires like crazy trying to scale jumps or do a wheelstand down the straight when the truck does hooks up.. No power concerns there :D

The Cobalt needs a lot of maintenance though.. the brushless would eliminate that ...


:cool:

Bugs

[nicholcgn]

You can dig through the forums and find some information. Or you can go out to some tracks and just ask people for help. Many of them will not give you the "superspecial only I ever thought of it" secret but they will help you a lot. My friend started with a lathe. Then talked to some onroad guys that would help him because he is only "offroad". They he started polishing bushings, shimming the motor and it progressed. He now has a brush combination that gives good power and helps lubricate the comm so wear is less. This is great for club racing. So I actually have 2 different brushes on my motor. And no I do not ask the combo. He does my motors and If I don't know it I can't tell. Then if we runa bigger race or series we can change to a brush that gives better performance but wears the comm more. (Did I mention this can get quite involved. Guess that is why I went brushless.)

He found out that the same brand motor can be quite different from can to can. Also most onroad guys seem to like RPM and Offroad like Torque. Also Dyno #'s can be missleading. Some motors dyno poorly but under certain tracks and conitions they are the bomb.


From #'s I have seen and people racing, Monster Stocks seem to be pretty good all around. I like my p2k2pro. It is all about what you like in the vehicle. Also if you get into maintenance you will probably want to get a motor you can get arms for fairly easily.

Most people will do a min maintenance between heast of cleaning the motor, Pulling out and inspecting the brushes, Clean the hoods, little oil and put it back together. If the brushes are bad enought they re serate them.

[Bugs Buggy]

Well, I raced tonight and didn't do well... my driving was awful :rolleyes:

The 18 tooth pinion did help with the P2K2, although a did notice a slight loss of top end. The track was slick tonight though, and I probably should have stuck with the 19 tooth pinion... Perhaps I'll do that when I race again and set the GTX up to 1 instead of 3...that might do the trick!

I might race my FT B4 as well... I may put my P2K in there and see how it does. The last time I attempted it, I had brand new tires on, the speed control set to kill, and I used a 23 tooth pinion... needless to say, the thing was a handfull :D This time I'll set my GTX to 3, use a 24 tooth pinion and use worked in tires...should be interesting :)

:cool:

Bugs

[gizmoguy303]

Where do you race at Bugs?

[Bugs Buggy]

Tacoma R.C. Raceway, Tacoma, WA