rfn026

If I were going to build a Solo car I would think Miata. They're cheap and there's a tremendous amount of support out there for the Miata.

I just met the head of Mazda racing last week. 46% of the cars in SCCA are Mazdas. Mazda sells over $10 million dollars of racing parts to Mazda owners every year.

Richard Newton

BrianCunningham

Miatas are the NASCAR of autocross

they suck all the air out of the room

Given Mazda's sponsorship with the SCCA they'd never get banned
ban Corvette sure _anything_ Mazda No
that's not going to change, $$$ talks

dhowdy

What are you talking about? What corvette got banned? There are a lot of classes that a corvette is class competitive.

strano@stranoparts.com

No Corvette got banned. I don't understand all the hate talk myself, there are more than a few classes Corvettes are VERY competitive. But maybe not the C4, which at it's newest is 18 years old. A kid born when the last one rolled off the line in Bowling Green can vote, and be sent off to war.

Cars can't stay "fast" forever. When you have 300+ HP V-6 cars and Hatchbacks with 2.0 Turbo 4's making more power than an L98 ever did, and damn close to LT1 power... well times change.

I've been part of SCCA for a long time. I certainly have my issues with the club, especially lately. But the sour grapes is the same kind of complaining we hear from a guy with an old 911, or an old 320i. There is a bit of a marque club mentality, and that's fine if that's what you want.

theseal

The static camber is significant. But the early c4 front geometry is better than a c5-7, and I'm not at all sure that it's that clear cut that c4's can't win.

Guys like lane are flat hauling *** for sure. But these cars may surprise. Much narrower. 8" less wheelbase. Put down power much better. Less weight. Lower cg. More front tire.

They only have 245 horse. But 345 torque and good gearing. They are frame noodles and are hard to see out of. We may see soon.

All you have to do is see the shock on all the nasa tt people this weekend as terry fair broke the ttc lap record at msrh by 7 freaking seconds the first time a c4 showed up on equal tires -- so don't write these cars off.

Solofast

The c4 front end geometry is only better at high steering angles that you see in real slow events. While a lot of regional events are slow the courses at Nationals aren't. NASA doesn't restrict negative camber like SCCA stock classes do. The old BFG tires developed in the 80's and early 90's were designed to work with the limited negative camber that the Corvettes (and most cars in those days) had. Those tires had more rounded tread than street tires and tires like Hoosiers and it's a lot harder to get a C4 to work with tires like that. You end up eating the outside edges of the tire, or you have to put in higher pressures to avoid ruining the tires and that hurts front end grip.

When the C5 was being designed the guys who autocross had a conversation with the guys designing the suspension. The designers thought that racers would "get what they needed" and didn't understand that you couldn't just put in offset bushings and things like that in the stock autocross classes. The guys designing the suspension then asked "well, what do you need". And the response was "get us at least 2 degrees of adjustment", and that's what they did.

If you look at the C4's that ran BSP and compare them with the C5Z, the blueprinted LT4 had about the same power (we had 400 hp at the flywheel in our BSP car), same weight and a bit more tire, and with offset bushings we could get the negative camber we needed, and that car ran about the same times as C5 Z06's.

There's no way with stock negative camber you'll get a C4 to have as much front end grip as a C5 even with a bit less wheel width.

I ran C4's from 1989 to 2000 in the stock classes and ran with the best every weekend, and then ran a C4 in BSP for four years. I'm intimately familiar with the car and what the limitations are. And yes, Scott Mc was faster than I ever expected him to be in his car, but that was really the last hurrah for the C4. The reality is you just can't get there from here.

The SCCA has a policy of "new replaces old" in Solo. That is, don't expect your car to be competitive if it's getting old. The reason is that old cars get harder to find, maintain, and police in stock. Just because your car has a class, that doesn't mean it'll be competitive and the C4 is there.

BrianCunningham

2015 CAM handout b.pdf

B4CHawk

The purpose of that is to prevent someone in a relatively stock C5/C6/C7 coming in and cleaning up every event. The purpose of the class is to bring new people in from Good Guys events; not scare them off at their first event.

B4CHawk

Every event has a different course designer. Some events may favor power, some may favor agility. I think it's nonsense to declare the SCCA "anti Corvette". You come to the events, drive the course that's given... roll with the punches, so to speak.

BrianCunningham

Yes I realize that

I was just running CAM to help support it.

My point was the later Corvettes were BANNED.

As a matter of fact World Challenge got started when C4's got BANNED from running in their class because they were beating everything.

http://www.superchevy.com/events/vem...tte-challenge/

greendot

Yeah, I used to have a magazine ad on my office wall that said
"Nobody's perfect"
It had, as I recall, finishing positions in a race with all Corvettes top 10 except one Porsche in 9th place or something like that :-)

theseal

Thats a great post and true facts. But in my opinion, (no offense) bsp was never fully understood or developed. There were a lot of good cars, drivers and people in it. I have the utmost respect for them, and i never won bsp. But since weak-*** opinions and lame excuses are part of any good racing discussion, i'll share a bit.


i thought i could identify several things in each car that were major handicaps. My personal experience one year supports that theory.

i started in mid-august and took a stock 96 vette, put headers, flywheel, 11" wheels, and set the alignment -- and ran bsp for the first time at nationals one year. I was on kumhos (not the best tire) and my front swaybar mount pulled out of the frame on my first run on day 1. Causing a spin. I yanked the swaybar off the car in grid, and coned away a top time.

Next day, we ran a really stupid tight course, i ran it lugging in 2nd twice and tried riding the rev limiter in 1st out of desperation the last run. None were any kind of good run. But in a half *** car, 200 pounds overweight, 20 horse down; missing many key parts and never tested, on 315 kumhos, instead of 335 hoosiers, with perfectly wrong gearing (no 3.54) and NO FRONT SWAY BAR ON THE CAR i set 3rd fastest time at bsp nationals on that course, 3 tenths off the fastest lap. And BSP that year beat a couple of pretty solid SS drivers, Ames and Stelnieks, by over half a second.

The next year, when Berry won, there was only one dry day, but SS only had one hotfoot that 'officially' ran a 55.3, one other that ran a 55.8, and the rest of the 8 former national champions and 43 other guys in the class couldnt get under 57.

ASP, with c5 supermen like Popp and Thomason only managed 55.0 and 55.2 respectively. BSP managed a 55.1. In street prepared form, even the 'in my opinion' handicapped c4's, proved quite equal to a street prepared c5z06, at least that day, and that was a really big course.

The moral of the story is simple, i still think c4's are incredibly underrated. And misunderstood.

I still have one. I am having too much fun with huge horsepower to really devote much effort to the c4, but i just may try to put my money where my mouth is soon.

greendot

Back when I was running BSP I had a debate with Guy Ankeny, who built the black car that Tom Berry won with, about the merits of early vs. late C4 front susp. He was adamant that the late was better. I prefer the early having had both. Roger Johnson's test of the 88 vs 86 supports that, FWIW.
Of course Solofast never liked my car setup

acrace

Greendot:

A few of us, back then, also had the theory that as much tire testing as Roger did with the yellow '86, in helping to develop the various BFG R1 iterations, that the BFG tire was perfected optimized for the early C4 suspension, and that was a contributor to Roger being not as quick in the '88. I should've bought the '86 when he offered it to me, in the spring of '88.

greendot

Rest assured that it has a good home

I also recall one year that I took it to Nat's and ran the stock class and got whopped by (don't recall his name) in a blue late C4. My excuse is that the 16" tires by then were not as good as the 17's and I'm sticking to that.

FAUEE

I agree, I'm just saying, in my area, the guys that design the courses, along with the majority of the members, are Miata or WRX drivers. They had an "unusually fast and long" course that had nothing but left right left right turns, the closest thing they had to a turn exit was a short section at the end of the course that was right before the exit. I'm not even entirely sure it was in the course, because I saw a lot of the other cars not going WOT in that section. So either half of us were loud obnoxious morons, or the other half weren't going WOT at the end and went a little slower than they could have.

FWIW, every American RWD car at the event except my C6 GS and my buddy's C6Z51 spun at least once on the course. Every Mustang, Camaro, and other Corvette spun. Heck, even an STI spun. The average speed for the "unusually fast" course was like 25 mph. It truly was a bunch of people driving around in a parking lot.

I switched to HPDE after that.

Solofast

I agree with both of you...

In the early days of the 17 inch wheel cars the 17's weren't as good, or they didn't work as well on the front of the car (the early suspension being better, but also the tires were tested and developed on that car and they worked fine so the stopped developing them).

By about 1993 or so, the 17 BFG inch tire improved to the point where those of us with 17 inch cars could be competitive with Roger and depending on the day, the course, the surface and the phase of the moon, it made for a good race. Earlier we just didn't have the tire to compete, but later on the 17's were as good as the 16's or perhaps even better.

Solofast

If you looked carefully at Guy's car he installed some front upper control arm bushings that gave that car a huge amount of caster. His custom bushings moved the upper control arms aft about an INCH!! I'd bet he was running more than 12 degrees of caster to get the zero scrub front suspension to work.

When I asked him if that helped he got real evasive, he wouldn't look me in the eye, he looked down at the ground, shuffled his feet and mumbled something to the effect that "it really didn't seem to make much difference"....

And if you believe that one I've got this tower in Paris.......

theseal

the problem with the later cars is massive SAI (kingpin)... and also rack relocation for bad ackerman and bump steer.

SAI COUNTERACTS caster, as well as jacks the car up when you turn the wheel, overloading the outside front tire. What guy was doing was a crutch to overcome this, but it is still a crutch.

PS, guy is a lot smarter than me in a lot of ways, but I personally hated all the cars that people told me he set up. just didnt fit my style. maybe they screwed with guy's setup before i got to them though. you never know.

Solofast

No question that kingpin angle is the crux of the problem but the rules in BSP don't allow you to relocate the suspension mounting points or fix the kingpin angle, so within the rules what Guy did was perfectly logical, and I'm sure it worked. Higher caster reduces the outside tire loading due to jacking and also increases the amount of negative camber at higher steering angles and trust me it really works. I don't think it was a "band aid", at all, it was a logical approach to fix the problem within the rules. Bottom line is it worked and he won with it.

We had an early (1984) front suspension on our BSP car so we didn't have to do that, but on my stock class cars I ran as much caster as I could get within the stock parts and I can tell you for a fact that a even a small amount of increased caster really helped the later cars.

The problem with stock class cars is that you have to give up negative camber to get any more caster and that's not a good trade either. This makes the earlier cars faster on slow courses, but on faster courses, the steering angles are smaller, and the kingpin angle isn't a factor. At that point the better engine, better transmission and better rear suspension all come into play.

I think the best C4 is a 93 or 94 Z07 car but that's just from running 9 different C4's from 89's thru 94's during those years.