Well people, finally I have got some time to finish this megapost that I will call
"TC Technical" to show and share with you some pics I took in one of the last TC races I went last year.
There are some interesting things to see, sometimes it may be hard to understand the whys but just in that case here are the TC Rules:
http://www.actc.org.ar/php/reglamentos.php
The first thing to understand is that there are 4 TC categories:
A) TC
B) TC Pista
C) TC Mouras
D) TC Mouras Pista
The top (and most competitive) series is the TC. When TC top teams build a new chasis, they drop their cars to smaller TC teams or to TCP teams... and top TCP teams drop their cars to TCM teams and so on.
This happens because one of the things where TC rules let engineers and designers free is in the steel frame structure. The best cars wont last more than 1 season before that they have to be reinforced/repaired with the obvious weight increase.
Structures are incredibly rigid (
600Kgm torsion tests show arround 1mm deofrmations) and light taking in account that they are Ø50mm x 1.25mm MIG or TIG welded steel tubes.
In those 4 categories there are 4 "types" of cars allowed:
It is mainly because of tradition, that the external shapes and old engine cylinder blocks are still used:
* Ford Falcon
* Chevy SS
* Dodge Polara or R/T
* Torino (Argentine 70s car)
As it can be noticed, Dodge and Chevy has aerodynamic advantages over Torino and Ford, so the rules allow a couple things to help balance things:
That rear spoiler design is at least weird and I have seen it in many cars. Also I have heard that the roof top deflector have helped Fords to reduce the stall that produced a big downforce drop between 160 and 180 Kph and that disapeared at more than 180kph to regain downforce. Yeah, Ford drivers are special dudes and not any driver can adapt to that.
Another thing that is ruled to help balance things is front suspension geometry: 3 of the 4 wishbone-chasis mountings have a "window" of arround 50mm where you can place them. The 4th is free. Damper/spring mounting is also free.
BTW, the steel disc rotors rules changed a while ago to a 5Kg minimum front and 4 Kg minimum rear after some top teams where qualifying with special 1.5Kg rotors.
Rear suspension geometry is free but it has to be a live axle with 4 links. Check this weird damper-spring mounting point:
I guess they where looking to have a motion ratio that is different in bump than in roll. There was only 1 team I saw using with this stuff.
At the engine department, we have displacement limited to 3110cc. The ACTC (governing body) changes compression ratio for each make whenever it feels to, and they are in the 9.2 to 9.5 region.
Engines are straight-6, OHV of course, 2 per cylinder and feeded with one Weber 48 IDA carb.
They pump 380HP at arround 9500 rpm and there is a development going on to place aluminum multivalve cylinder heads and reach 450HP out from a 3 liter NA engine... with a block that was designed in the 50s!!!
With the current engines the top speeds are arround 280Kph, remember TC doesnt use oval tracks!
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Beyond "aero" rules being rather strict, there are interesting aero bits to analyze
Here I caught these guys changing the oil radiator intake (iys in the hood) and then I noticed that car had a chaneled-to the floor oil radiator exhaust:
The other cars use to have the oil rad together with the water heat exchanger, at the lower front.
Also, as the rules prohibit "closed wing profiles" at the front, some guys that need front DF uses craps like this:
Notice the cloth skirt that its allowed only at the front. The floor must be flat and cant have diffusers.
Finally, I have heard that these cars do well with more than 7° of caster. Power steering is not allowed and the cars weight 1200Kg, so the drivers that can withstand a race with a 9° caster and still be able to turn the wheel in the last lap has an advntage. TC is for "machos", the ACTC president said. I hope all the training Jose Lopez did helps him for this season
Thats all for now floks, Im off to bed now.
"You need great passion, because everything you do with great pleasure, you do well." -Juan Manuel Fangio
"I have no idols. I admire work, dedication and competence." -Ayrton Senna