4-tec really hitting 70?
 

I am just wondering if the 4-tec is truly hitting 70 mph. How much power does the 3.3 engine have if it is a 20. Does even accelerate fast because of the gear size required to hit that speed with only a 2-speed. Does it have a 3-speed?

The only car i have herd of with such speed is the scumcher (spelling?) which as a 3-speed in it.

RE: 4-tec really hitting 70?
 

The Schumacher Fusion and the 4tec have engine sizes that are almost identical. The 3.3 might out rev it and produce more legit horsepower at a higher RPM.

Further, it doesn't mattter how many gears you have, the final drive ratio, the redline of the engine and the horsepower and torque curves will ultimately determine top speed.

It is possible the 3-speed actually allows the Fusion to overcome it's engine's less flexible powerband and lower redline. Additionally, traction is now the only thing that prevents cars from acelerating even faster. Both are probably restricted by the size of the tires on 1/10 touring cars. Engines now can overpower the tires...meaning that extra power won't make an already over-powered 1/10 tourer get up to speed any faster.

The tires are ensuring that these cars probably perfrom very very similar in terms of accel.

RE: 4-tec really hitting 70?
 

I have a hard time believing that the 4-tec 3.3 can reach speeds of 70mph. After seeing what the engine could do in a t-maxx (not much better than the 2.5) I don't think that Traxxas' claims of 70+mph is feasable.

RE: 4-tec really hitting 70?
 

I have the 4tec 2.5 and its hitting just about 70 or just a lil less but here is a video i made with mine. Its all stock nothing added to it.
http://www.ripclan.com/Downloads/4tec2.zip

RE: 4-tec really hitting 70?
 

i read somewhere that someone put foam 1/8 scale tires on the 3.3 4 tec. he claimed it improved the speed and handling extremely well. .........i wonder how it looked?.

RE: 4-tec really hitting 70?
 

i tried to download your video file but was unsuccesful.not to be a smart---,... but i would have loved to see this stock 2.5 4- tec do 70 mph. i know two people that have 2.5 4-tec's and using a radar gun they would only hit around 50 to 55 mph.......if they were lucky!

RE: 4-tec really hitting 70?
 

I was able to download the video and yea that definatley wasn't 70mph. Looked more like 55 to me and it took a good 10 seconds to get to top speed. Do you have any actual radar tested speeds/ time calculated speeds to prove that your actualy going 70 or think it looks like it's going 70. I have an rs4 with a ratio slightly higher than stock and an os 18 cv-rx and mine tops out at 62. The major difference between mine and yours is it takes me 2.2 seconds to get to that top speed.

RE: 4-tec really hitting 70?
 

THAT IS RIPSTRIKER WITH THE 70 MPH 4 TEC. I DID FINALLY DOWNLOAD THE FILE AND I DO NOT THINK IT IS GOING NEAR THAT FAST. THE ONLY RC CAR I'VE SEEN GO 70 PLUS MPH IS A 1/8 SCALE CAR WITH A $470.00 DOLLAR RACING ENGINE IN IT. BUT....I HAVE HEARD THAT THE 3.3 4-TEC DOES HIT 70 MPH.

RE: 4-tec really hitting 70?
 

CT5

RE: 4-tec really hitting 70?
 

I was talking to ripstriker. I apologize if there was any confusion in my post.

RE: 4-tec really hitting 70?
 

I have a Nitro 4-tec and have been clocked at 68mhp . By a police radar gun in my high school parking lot. it is possible. the 2.5 motor does not really got on top off them. you really need about 500 ft of straight away. to get there . i ran out of space . My 4-tech is bone stock. you should not hate on a car. That does need to get hooked up out of the box. So you can keep up with other peoples cars.

It is possible to get to that speed . I also depends on the weather . I have found that the 4-tech runs faster when it warmer outside . unlike the Hpi cars . The 4-tech gears are super tall. be for you gear start hating check it out . Also the Rpm of all Traxxas motors is about 7000rpms higher than most motors out there.

RE: 4-tec really hitting 70?
 

Thats exactly my point. If you need more than a football field to get to there predicted top speed than it's as if you never reached it in the first place. Also how is that you got 68mph out of your 4-tech with stock gearing when your engine would have to be pulling more than 45,000 rpms.

RE: 4-tec really hitting 70?
 

like I said it was a warm day. so i was running my motor lean . i don't know how long the lot i play in is but it is not that long. it is sad that you cant understand how that is possible . it seems you have not been doing RCing for long . If you have been, you would know that your motor will act different depending on the weather. basiclly the warmer the weather the faster you run.

RE: 4-tec really hitting 70?
 

I've been in to RC for 7 years now and have never heard of a trx 2.5 reving over 40k, no matter what the weather conditions are. Are you truely using the stock gearing that came with the car, in other words did yo buy it used and it came with a taller gear ratio but you thought it was the stock one. Then possibly you might be able to reach that speed but I still find it highly unlikely.

RE: 4-tec really hitting 70?
 

Well boys down here in Miami are getting Traxxas Jato's to run over 80mph in less than 250 feet.

RE: 4-tec really hitting 70?
 

is that 80 mph in spanish or english?

RE: 4-tec really hitting 70?
 

LOL

RE: 4-tec really hitting 70?
 

Do not laugh it is true some guys even have .21 engines in them and yes that is true because I have personally seen one.

RE: 4-tec really hitting 70?
 

As for Russell if you do not believe me come down here to Miami and find out for yourself if I am lying or not.

RE: 4-tec really hitting 70?
 

Ok now I can understand how there getting 80mph. But I still don't get 68mph out of a stock 4-tech 2.5.

RE: 4-tec really hitting 70?
 

No they are getting over 70mph out of TRX 2.5 and over 80mph out of the TRX 3.3, the .21 guys just do it to say they have a .21 in there Jato.

RE: 4-tec really hitting 70?
 

Hey guys maybe I can help a little. I just bought the Traxxas 4-tec 3.3 last week . I was able to break it in and then started to corner agressively and destroyed the tires. But I will say that the car is incredibly fast! No i didn't time and calculate it, and no I didn't get a cop to radar it (something i'm working on trying to setup....) but i will say this....

I have a savage 4.6 with 3-speed and a 19 tooth CB. (On the box it says approx. 44mph top speed with 18 tooth CB and 25% nitro) also the 3-speed adds 10% top and bottom end so 10% of 44 mph (even though i have a higher CB gearing) is already 48.4 mph so roughly 50mph my truck will go. I am not trying to brag or be cool just rationing a reasonable comparison. I will say the car looks MUCH faster MUCH MUCH faster I have not raced the two yet but soon as i can afford some new tires (car tapped me out :) i will let you know the results of that. In my honest opinion the car is at least capable of 70. Maybe they mean on a slight downhill grade or something u know? Just looking at it and judging its top speed vs my savage i'd say its a safe claim that it would do a good 60 if not more. Also take into consideration that i had about 150 yard square parking lot (empty) so I could only do a sustained full throttle for a few sec then full brakes or TKO. So maybe if you had room it could hit 70. I don't want to make any outrageous claims but I will definitely say their claim is nothing to scoff at!

My friend at work dates a local sherrif, we talked about this and he said the same thing (prove it) and is trying to arrange a radaring... IF this happens i will take pics of the radar display and post for you guys.

Till then its just MY OPINION :P

RE: 4-tec really hitting 70?
 

my friend jato 3.3 is hitting 54mph!!

RE: 4-tec really hitting 70?
 

In the issue of RC Car Action Magazine they did a speed test on the 3.3 Jato and got a top speed of 67mph. So all of you who think your getting 80, think again.

RE: 4-tec really hitting 70?
 

my 2.5 jato will go that fast. it was clocked with a gun at 53 mph.