loftygoals wrote:
I wasn't arguing that the R888 was a better tire. I was saying that it was a cheaper solution. In fact my thoughts about tires and sizes were purely cost motivated. I was looking at it like the HP factor--equality and cost is more important than making the cars go faster.
I can see where a faster tire with better characteristics helps the class, though. As a driver I like going faster, not slower. I'm sure the RR will be well received and an awesome tire.
The RR is worth it. I think the class would mutiny if we went back the R888!
I respectfully disagree. While I agree that installing torsion bars isn't rocket science, the indexing process is a lot more difficult and time consuming than a coil spring on an adjustable collar.
No question/argument here!
It is nearly impossible to get a perfect corner balance without re-indexing. Even if you set the rear so the height adjustment eccentric is in the middle of the adjustment range, that only gives you a 1/4" of an inch movement up and down.
My turn to respectfully disagree! I'm really fussy about corner balance, and I do it myself. After years of borrowing scales, I went in with another guy to get scales, because we do it quite a bit. I can get the car to within 20lbs per corner (nearly square, not just cross weights). A little ballast helps.
Get the chassis level to start - you'll be very close. Most of the time, I can get it perfect just using the front coil overs, keeping the ride height within 1/4". When I need to use the rears, they've got plenty of movement. It may be 1/4" at the plate, but it's considerably more at the wheels. I've re-indexed once over the years, when I went to a lower ride height.
Now, I'm not saying it wouldn't be easier with rear coil overs, but it's very possible to get a good corner balance as is.
Book time for replacing the torsion bars is 7.8 hours. My shop charges less than any other Euro specialty shop in Dallas per hour-$85/hr. That's $663 just to get the bloody torsion bars installed. If you are going to one of the specialty Porsche shops, you'd pay $115 an hour or $900 for the job.
Now, for $900 I'd do nothing but install torsion bars all day! That's a lot of money to replace some springs.
So besides the complexity of making ride height adjustments, what if I want a different rate? There another stack of cash or 8 hours of your life gone, not to mention the expensive price of the bars themselves.
This is the strongest argument. How much time does it take to remove the torsion bars? What would be the total cost for that & installing the coil overs?
Sterling Doc wrote:
We run the Koni's because they are an inexpensive option that has a cheap fitment for our cars. As long as we're all in the same boat, and the cars are fun to drive, it matters less wether it's optimal.
To me this isn't a good argument. If performance isn't important, why not run a cheaper tire? A street tire maybe? They'd last forever and everyone would be in the same boat.
OK, but first you have to show that the incremental cost is balanced by a significant performance difference, at the level of spring rate we run. RR vs. street tires is more than 3 (probably 4 seconds) per average lap. In 944 Cup, and in GTS-1, Koni shod cars are competitive. I don't see the bang for the $.
The truth of the matter is that we are racers, we like to tinker. We like racer parts on our cars.
But we don't like racer part prices! Adjusting rebound is useful. Double, or triple adjustable shocks take pros to set up well - out of our scope as a Spec class, I'd argue.
They are street shocks. They carry no warranty for racing use.
I don't know what shocks you have in mind, or what they cost, but I look at Paragon, and see this:
The 30-Series rear damper is considered a racing component as such does not quilify for Life Time Warranty. At the price they run, the yellows are fairly disposable in any case.
While the fronts for all the cars are nearly the same, the rears are vastly different. The early rears are monotubes and the late are twin tubes. The late shocks can be run lower than the early because of this design. Additionally the adjustment on both of the rear shocks is a pain.
Interesting, and yes adjustment of the rears is a pain.
For what we get, the Spec suspension isn't cheap. Here are prices from Paragon's site for an early car:
Front Coilover Kit - $265
Front Koni Sports - $190.40/ea
Rear Koni Sports - $141.40/ea
Sway-Away Torsion Bar Pair - $295.95
That's $1225. That's a lot of money for this setup.
There is a small discount to order it a as set with antisway bars, or save a bit shopping around, but, OK, call it $1,200. It's $700 more for the Escort Cup 4 corner coil over, which is the cheapest option I see (and is only an option for late cars). But more than that, it's well over $2K to do the swap for the installed base of cars.
Speaking hypothetically, what if there was a purpose built front and rear coilover setup engineered specifically for the 944 Spec class that allowed height adjustment, simple knob type damping adjustment, a multi year warranty that isn't voided by racing, cheap rebuilds, and uses standard size coil springs? If the price was within a $100 of the current Spec suspension, do you think people would want them? Would it be worth the pain of converting the entire class?
Getting by all the hypotheticals, your proposing a roughly $1,300 cost per car for parts, labor, and re corner balancing - $2K total? While that is reasonable for what it is, as an added expense over a currently functionals & competitive race car, it's just not practical for what you gain (mostly convenience).
tcomeau wrote:
If we went to springs in the rear, I'd need at least several sets of springs for different tracks.
Remember, simple, cheap, equal.
To be fair, you could do this within the rules today. For example, you could run a 400#/30mm setup for smooth tracks and a 350#/28mm setup for rough tracks. No body does, because it would be a PITA.
We could simply specify a spring rate, or a max rate like we do now. I know we don't specify a max for the front, but by limiting the rear to 30mm, the rules effectively limit the max
usable front rate.
I'd agree, we don't need different spring rates any more than we do now. Max rates are soft enough that there's not much, if anything, to be gained by going softer yet.
Just thinking outside the box here.
Understood, and it is interesting to think through, but major, and expensive rule changes are a HUGE deal in a Spec class. Adding less than <$200 of cost in dynos this year generated 24 pages of discusion!