dodgeguy

iTrader: (208)

I just started running the pro 4. I think it is great. I plan on running it for a while. If the Cyclone comes down in price. (do not see that happening) I would think about trying one. Due to the same suspension on the 2 cars.

But the pro 4 is fast. I also think if HPI sponsered local racers the car would be more popular.

AngryAsian

iTrader: (4)

Can someone explain to me what torque steer is?

I've always assumed it's the steer effect you get from drivetrain component torque reaction... obviously causing the car to steer in one direction.

I run a GTB in my Pro4 and have never ever seen this affect on acceleration.

Or am i looking at the wrong thing? Does torque steer make the car steer more in one direction once at speed as well?

As far as i know, my car is pretty evenly balanced from left and right. All settings are correct but it seems more glued turning right than it does turning left.

It's a little more reluctant to steer left.

Any thoughts anyone?

nomaak

angryasian...if you've ever seen a tractor-trailor truck take off from a dead stop. or seen a semi-truck pull competition....you'll notice the cab will "twist" in one direction. those vehicles and shaft tourers have similar drivetrains...a shaft leading to a gearbox/differential to the rear tire. the drive energy first goes down the shaft, then it has to drastically change directions. the energy of that abrupt change has to go somewhere and the suspention is the easy way out. from there on out it gets above my head but i hope you get the idea.
this has always been a problem with shaft cars...but the immediate acceleration these cars have sorta over-shadowed this problem. but now that belts systems are becoming so much more efficient the "holeshot"advantage shaft cars have is now starting to fade. plus the energy all goes in one direction making a more stable platform with no tork steer. (i think ...guess staying in a Holiday Inn Express didn't help much. )

dodgeguy....yeah the pro4 is a good car. and if HPI had more top level US guys on their team the car would have lasted as long as the tc3. heck it may have been a little faster. the pro4 was designed under a one-man team....Atushi Hara. he's had the greatest influence on the car bar none! he's a top guy alright...but from japan. and those tracks (where the pro4 was developed) are a LOT different from what we run here week-to-week. honestly.....how many US tracks you know of that uses one-way diffs? not many...but over there it's more popular to use one-ways (that's why the pro4 comes with one). that is why i beleive the car was sold in the US but the package still catered to the over-sea's tracks. that's why it has such a lack-luster following here. the car LOOKS good but..looks aint everything. but for this season of racing i'm gonna try one more thing to get this car to feel better. i cut out all the battery slots so that i have a big rectangular hole. i then used a battery tray from a shuie MI2 to mount my batts.
i set it up so that my cells are dead center in the car (stock wheelbase). then i bolted & shoo gooed that tray down. i used heat forged 3/4" acrylic to make everything was SUPER flat. hopefully i can get a good feeling in my racecar this time. if not then i'll sell it and go with my ole tried and true X-ray T1.

Oasis

iTrader: (38)

I have raced a Pro4 since it came out,I do not notice the torque steer,I feel that the problem is more theory than reality,Not everyone can drive this car and do well with it,(It's just an opinion)I race a bone stock Pro4 and in the stock class nothing is faster than a Pro4(once again an opinion)For me the Xray T1R just plain SUCKED..yes I said it.. The best I ever did with the Xray at my local track was 4th,The first race with the Pro4 I won..and I'm still winning..Their are a few RCTech members that race at the same track as i do that know how fast a Pro4 can be.. All I can say is if you have to do radical changes to the car(see post below)either you have completely missed the set up or the car(in this case Pro4)is just not for you.I had this "problem" with Xrays..everyone was fast with this car but me.. I never did figure out why this car(04FK)was so slow in stock.I do know a few guys that were slower with the Pro4 compared to other cars.I guess my point is when you start having to make "huge" changes to the car it's not the car it's your driving style does not fit the car.I would change cars,why spend all that time on a car that is never going to work the way you want it to..

nomaak

i agree...but in order to race on carpet, don't you have to make huge changes anyway? ie ; thicker chassis and top plate? too me spending the $$$ on an already expensive car is huge enough. besides i said x-ray T1 (pillow ball car) not t1r. that car was too flexible. balanced but flexi. i've always had better success with saddle style cars anyway (more balanced IMO). i just thought i'd try and balance the thing up for my tastes. besides it IS a RACE CAR! i rarely run stock anyway...(too boring). mod is more my speed. IMO why buy a top caliber car only to limit it in stock? mod is what this car was MEANT to run. at my home track there'd be plenty oh stock and hardly no mod, so i would race against the nitro and 1/8 scale guys. car was AWSOME outdoors, but when it came to indoors on carpet...well, let's just say it wasn't pretty. that's where my x-ray came in. super balanced and super smooth. and now i've got way better batteries and motors (my sponsor's a GREAT guy!) i'd like to dump the "dino car" as he would say, and try th pro4 once more.
with the only carpet track in NC being 3 hours away....R&D testing is far and few in-between. so when i do go way out there, i would bring i car i know. but i'll test up thru the novak race and maybe i'll have something for snowbirds.

nomaak

and i appreciate your reply it was good brain food.

Oasis

iTrader: (38)

Carpet is all I race.. (I own the track)I have spent a lot of time with the Pro4 on carpet and yes you are right in your opinion of the thicker chassis being better for carpet,How ever one of my racing buds uses the 2mm chassis and the 2.5 top deck and the car seems to work a lot better than the 2.5mm chassis with the 2.5mm top deck.. It does seem to be a good compromise between asphalt and carpet.I do prefer a belt car for mod though.. But in the area where i race,stock and 19 turn seem to be the only classes anyone runs.

nomaak

gotcha...since hara races all over the world, he has special chassis' for nearly every venue he goes to. say for instance...rubber tyre on carpet in Europe....he may have a special cut fibre chassis set @ 1.90mm thick with the fibres going from front to back. or in aisa it might be a carbon chassis laid with a 45-90-45 degree weave for a Reedy race outside. my point is...he's considered to be in the top 3 best drivers in the rc touring car world; yet his pro4 was nowhere Close to what we run every week. if the car was so good...and his skills are so far above average...why does he make such drastic changes to his car? it's as if it aint good enough to win races as-is. unlike the Tc3 and xxx-s. but from what i heard (from his mouth)....at this year's IIC in Vegas, he runs the cyclone as close to stock as possible. no crazy aftermarket stuff...no one-off plates and chassis components, just a plain ole cyclone. is this car so much better than the pro4?
not to pick a fight or nothin but, i hear AE team drivers STILL prefer the feel of their tc3's over the new tc4's. and the pro4 is all but extinct (already).

floodo1

well the pro4 is old. the hara edition coming out so close the cyclone was kinda wierd, but i think it was to make a final statement in shaft drive cars.

anyway the reason that hara changed his pro4 so much is because he's a world class driver, competing against the best that other manuf's have to offer. everything matters there, so you hAVE to take advantage of your special 1.9mm custom chassis.

but honestly the cyclone IS the succesor the pro4. much the same way that the msx is the succesor to the ms (415).

time marches on and new products come out. i plan on keeping my pro4 only until i can afford a cyclone.

and actually even here in the US i run exclusively front one-way (cuz i dont run foams).

oh yeah, i have a feeling that hara doesnt have to run his cyclone with special parts cuz its so fast to begin with! esp now that HPI has most of tamiya's good drivers. now only reinhard can challenge hot bodies!!!!

looking to the top level to find out what YOU should drive is hardly a good idea. i mean take a look at the Peak video showing 4+ different driving styles used by top level drivers at IIC. whats fast for hara may not be fast for you.

hara top3? i rank hara top 1 for sedan.

iblumberg

I'm still getting used to my recently acquired Hara Edition. So far, I really like it. For me, it drives far better than either the Team TC4 or the Losi JRXS that I tried previously.

As for torque steer, the Team TC4 definitely has it. It causes the car to veer left (if I recall correctly, but could be right) under hard acceleration when it would otherwise go straight if running slower or not accelerating. The Pro 4 does not seem to suffer from this problem. Several magazine reviews have even commented on how surprising it is to have a shaft car that accelerates like a rocket, but does not torque steer.

This was really brought home to me today. For fun I put an 8x1 mod motor in my Pro 4. It was blowing away 1/12 pan cars with 9x2 mod motors down every straight. It was scary fast. However, even under full throttle, quick acceleration, it tracked straight. With a Team TC4, you'd be gathering up pieces from the boards if you tried this trick.

As for the dog bones, I tried the MIP Shiny bones for a TC3. They are steel. I bent them in the first 2 hours of use. Then I switched to the new, thick TC4 alu bones. So far, so good.

Ira

AngryAsian

iTrader: (4)

hmmmm... so no torque steer for anyone?
Good'o.

i suppose if it's never happened then, not to stress.

Now.. can soemone tell me why my car steers more going right than it does going left?

Like i said, weight is even from left to right of the chassis. droop is all the same. i don't understand...

(i don't have a droop gauge, but by eye and feel it is as good as i can get it.)

Oasis

iTrader: (38)

Have you checked for tweak? If you run ANY car that has a top deck after every race you should check for tweak.If you hit stuff then checking for tweak goes from "should" to must..And on the subject of droop,Hara and the rest of the team drivers run different droop settings side to side(LR 6 RR 5 .. Just an example)I will bet your car is tweaked..

AngryAsian

iTrader: (4)

nope...

is there any reliable way to check the tweak without a tweak station?
(I've tried the lift each end up "test"... things eem okay. but really, that's very very rough)

Essnowyt

pwracing - How did your car work this weekend? Did our suggestions help?
Snowy.

Oasis

iTrader: (38)

I used to use this method for pan cars,You can find tweak stations for a good price.In the times of dual deck chassis it's a must have.