irish44j said:
Yeah, I can't see them being great on a FWD car, as they don't have great side tread blocks for turn-in bite. For the last 2 seasons (rallycross, not rally) I've run sharp-edged DMacks up front for turn-in bite (the stiff sidewalls are great for that too),
More kinda proof that there are whole different worlds in rallycross... I hate stiff sidewalls because on slow rough courses, they make the car less controllable, and on fast smooth courses they suck away horsepower.
And I don't get what this "turn in" you are talking about is... "Turning in" for my experience is hitting a bump but going with it instead of correcting it. Is why I like the relatively soft sidewall retreads, they make it easier to keep on course so head-space can be focused on the course and not kept inside the car.
Hmm maybe this is why I am completely lost on supersmooth courses like Frostburg or Indianola.
Knurled. said:
irish44j said:
Yeah, I can't see them being great on a FWD car, as they don't have great side tread blocks for turn-in bite. For the last 2 seasons (rallycross, not rally) I've run sharp-edged DMacks up front for turn-in bite (the stiff sidewalls are great for that too),
More kinda proof that there are whole different worlds in rallycross... I hate stiff sidewalls because on slow rough courses, they make the car less controllable, and on fast smooth courses they suck away horsepower.
And I don't get what this "turn in" you are talking about is... "Turning in" for my experience is hitting a bump but going with it instead of correcting it. Is why I like the relatively soft sidewall retreads, they make it easier to keep on course so head-space can be focused on the course and not kept inside the car.
Hmm maybe this is why I am completely lost on supersmooth courses like Frostburg or Indianola.
I don't think there's any question that we both drive very different styles lol .at our last event somebody told me afterwards that I look like I was going pretty slow, which is why they didn't have any pictures of me LOL. That was the event where I won MR and was 2nd overall out of 40 cars. Then again at panthera there's a lot of badness out of the course, so we tend to have a pretty good amount of outside cones. That rewards tight lines..... you will rarely see a picture of me sideways kicking up a rooster tail of dirt (except an old pictures at GLduvs and the rally farm). I would not call our current course smooth, but I also have my suspension setup to compensate for surfaces.
In reply to irish44j :
We rarely see you sideways with a rooster tail of dirt because for years you had a mild 4 cylinder engine 
I've never driven an E30 on course, but my gut feeling is that the "bubble" you ride when sideways is rather small, so getting sideways is not a good idea.
That's supposed to be where the MkII Escort really shines - it has a super wide "bubble". Drivers from the era said that they were wonderful because no matter what situation you found yourself in, or how crossed up you were, you could drive your way out of it. GC 2.5RSs are like that too - w had three drivers in one car (Tim White's car, with me and ZB co-driving) and we were all driving with very different driving styles, leaving in 1st gear, leaving in 2nd gear, driving neat, driving overaggressive, etc... and the times were all very similar, because the car is that forgiving with its wide "bubble".
(I've mentioned "riding the bubble" right? It's like, when you're in a corner, there's a bubble like on a carpenter's level, where if you go more sideways you will just spin if you apply power, but if you are less sideways you just push off into the weeds, so you have to keep it on that bubble to maintain control and modulate power as necessary. Orion's RWD 2.5RS had one of the narrowest bubbles I'd ever driven with its basically open rear diff and AWD-centric suspension. I'd love to have tried it with more front roll stiffness, less front brake bias (they locked up with ease now that they weren't connected to a transmission), and much softer rear suspension connected to a diff that actually worked, both in the "limited slip" sense and in the "didn't explode" sense)
irish44j said:
This thread also kind of makes me a bit sad.....because it's a sign that the rallycross "arms race" is becoming more like autocross. 5-6 years ago even at divisional events pretty much everyone was out there on secondhand take-off tires from stage rally teams (maybe a couple big-budget guys were buying new gravels), which was a great equalizer to see who was actually the best driver or who had the best car.
These days, the higher-level events seem to be heavily decided by who brought what tires, based on what our locals who have gone to nationals talk about. Hearing some of you saying you have 8 sets of tires for rallycross is insane. I can't think of many stage teams that carry more than 2-3 sets to a rally (SRT and other factory teams excepted). Y'all need to take that money and build stage cars ;)
The problem with used tires is the kind of rallyists who sell used tires after a couple stages instead of using them down to nubs, tend to run huge tires (like 17-65-15s aka 205/65-15s) which are WAAAAAAAY too large for 99.9999% of the rallycrossers. And the .0001" is buying new tires for himself anyway.
I made large increases in speed by going with smaller tires, because I don't have a 500ft-lb torque AWD car.
I kinda wish someone made a 15-65-15 gravel tire. (15cm tread width, 65cm height, 15" rim) As it is I am kinda happy with my 185/65-15s although when I bought some 175/70-15s I was disappointed to find that they were identical dimensionally.
Knurled. said:
In reply to irish44j :
We rarely see you sideways with a rooster tail of dirt because for years you had a mild 4 cylinder engine I've never driven an E30 on course, but my gut feeling is that the "bubble" you ride when sideways is rather small, so getting sideways is not a good idea.
That's supposed to be where the MkII Escort really shines - it has a super wide "bubble". Drivers from the era said that they were wonderful because no matter what situation you found yourself in, or how crossed up you were, you could drive your way out of it. GC 2.5RSs are like that too - w had three drivers in one car (Tim White's car, with me and ZB co-driving) and we were all driving with very different driving styles, leaving in 1st gear, leaving in 2nd gear, driving neat, driving overaggressive, etc... and the times were all very similar, because the car is that forgiving with its wide "bubble".
(I've mentioned "riding the bubble" right? It's like, when you're in a corner, there's a bubble like on a carpenter's level, where if you go more sideways you will just spin if you apply power, but if you are less sideways you just push off into the weeds, so you have to keep it on that bubble to maintain control and modulate power as necessary. Orion's RWD 2.5RS had one of the narrowest bubbles I'd ever driven with its basically open rear diff and AWD-centric suspension. I'd love to have tried it with more front roll stiffness, less front brake bias (they locked up with ease now that they weren't connected to a transmission), and much softer rear suspension connected to a diff that actually worked, both in the "limited slip" sense and in the "didn't explode" sense)
Meh, it was plenty easy to be sideways with the M42 if I wanted to. Sideways just isn't the way to win in rallyxross in a rwd car, Imo, so that's not how I drive.
E30 has a decent "bubble"...I mean it's not as easy as a Miata which a child can hold a slide in with 1 finger on the wheel lol....I've never rallycrossed a car easier than a Miata to make do what you want it to....
I'm not convinced you need as much torque as you think to turn the bigger tires unless they're starting to become super heavy relative to the car (which is an issue with rally tires). With 350-ish HP and a heck of a lot more tire than most run for rallycross (usually a 235/70R16 or 225/75R16), I've never once seen WOT in the Jeep on a course. Even in the faster slaloms where I can put down a good bit of power I still can't go WOT (partly due to traction even with an LSD at both ends and partly because there's a limit to how fast I can get it moving without losing it when trying to slow down).
In reply to rslifkin :
It's not a question of "needing torque". Narrow tires have more cornering grip because they can bite harder. Wider tires have more acceleration grip, while sacrificing cornering. So, you'd need to have a very powerful setup to where the lack of acceleration grip was holding you back relative to the losses you'd incur in the corners.
irish44j said:
You used to have the e28 right? by the way the venue at Panthera that we run now.....way more fun than either frostburg or the rally farm. Definitely try to get up here one of these days!
Yeah. I sold the E28 when the air conditioning packed up for the second time. The old R12 systems never really worked well with modern refrigerant. The 318ti I bought only cost a little more than repairing it.
I would love to try out the new venue. The worst part of living in Florida is how long it takes to get out of Florida.
Two events in with the Maxsports and they are feeling great. I run in mod-rear locally (in prepared-rear prep) and I am about a second per run behind the full prep cars on average. After the most recent event, there were some stones wedged into the bead of the tire. I managed to get them out with a screwdriver. The tire started at 32 psi but we didn't check pressures between runs. Do I raise the pressure or just try to stop understeering into berms?
In reply to ojannen :
Stop understeering into berms. Unless that's the fast way, in which case, make breaking the tires down and cleaning the beads a regular maintenance item.
If you have a 2x4 and a truck, you have a bead breaker.
Hey guys, I know I am a little late to the party here, but I have some info on Vaughn's tires. They are Alpha Racing Tyres. Used be called Unigom. They are Lithuanian retreads and really popular in European Autocross and Rallycross. Their Eurocross tire is similar to a IndySport SG and their Radial is similar to a BR. The Radial is what Vaughn was running at the National Challange in Ohio.
They are pretty expensive to get in the US because of shipping. If ordered in bulk though, I think they could be less than IndySports. I am looking into that now. I don't like the idea that there is one tire you have to run to be competitive.
Alpha Racing Tyres
-Ben
