140mph vs. 160mph

R

Ricisan

Active member
Joined
Dec 28, 2009
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Forum: Like many, I want to make my 74 a better high speed driver.
Perhaps do a HPDE day or two?
To me the problem is matching the parts to the speed being driven.
I'm sure the road undulations at 140mph are big whoops at 160mph.
I have no interest in building a race car, I just want to be able to drive the car hard w/o crashing or breaking something. User friendly power and balanced handling are very important. I already have most of the
VB&P parts on chassis: SSs, bars, brakes and lines.

I'm trying to get my Vette solid enough to run the 135mph rally car class in the Silver State. To me that means being solid at 140+.

The question is: Can I run 140+ safely 460/330 springs? I've taken off
#100 in front and intend to reduce sprung and unsprung weight. I don't want to make the car so stiff that the Mrs. won't ride w/me. LOL
This is assuming a few choice aero aids, stock in not an issue.

I run 315 rwtq at 4K, that should be enough power to pull a .70 OD?
My engine is good to go, I want the get everything else up to speed.

Some suggestions from those that know would be nice.

TIA

R
 
My only comment is about shocks, I find the Bilsteins are a huge improvement even at 80-100 mph really noticed the improvement on local bridge here, over the KYB that was my first choice....VBP 460 front and 360 rear spring.....

plus the obvious...trust NO speed indicator except GPS/Garmin........all else is bullshit, the stock instruments are no where near accurate in the upper regions.....meaning anything above 2500 rpm and 80 mph.....
 
I finally got to test my new 460 composite spring a day ago.... wow, what an amazing difference (good difference). Street driven, open tracked, car that doesn't beat me up.....
 
If I've said this once I've said it a hundred times. The biggest improvement you can make to a C3 is frame stiffening. If you've driven/ridden in a C5/C6, you have undoubtedly noticed how much better the ride quality and handling are than a C3. But what many people don't know is the suspension is actually more compliant than a gymkhana equipped C3. The reason they handle so much better, and the C3 handles so poorly is because the C3 frame ends up being a suspension component. It's not supposed to be, but it is. The ladder frame in our cars are pretty much horrible at resisting torsional and buckling loads, only slightly better performing than, say, a conastoga wagon.
Unfortunately, this means that any real improvements require the installation of a roll cage. Something I am not willing to do, as I feel you're against as well. Given that, I suggest you look for any ways you can to tighten up that frame. One thing I did years ago which did make a noticeable improvement (but it's still a far cry from where I would like it) is I installed a SFI scatter shield and tied that into the framerails parallel to the clutch. It ended up loading the driveline somewhat but I feel the benefit is worth the minimal increase in shifter and engine harshness transmitted into the cabin. That's just the first step in what I have in mind. For an even more, albeit not complete, view of what I'm thinking, check out THIS thread.
 
CD: I completly agree!
I already have the spreader bar, a 4 pt cage is coming.
Tightening up the chassis and making things user friendly,
is top of my list!

R
 
before I finish with the interior, I'm going to triangulate the riser to the rear suspension. I have the bits to do a suspension upgrade, and it'll need the bracing. On top of that, I'm going to run a bar from the roll bar to the firewall.... I agree, they are noodle soft.

My experience includes a 70 Buick skylark - and the 2nd best improvement I did was tie an 8 point to the frame (read, weld to frame)..... 1st was changing to b-body spindles and tubular upper control arms.
 
SuperBuickGuy said:
before I finish with the interior, I'm going to triangulate the riser to the rear suspension. I have the bits to do a suspension upgrade, and it'll need the bracing. On top of that, I'm going to run a bar from the roll bar to the firewall.... I agree, they are noodle soft.

My experience includes a 70 Buick skylark - and the 2nd best improvement I did was tie an 8 point to the frame (read, weld to frame)..... 1st was changing to b-body spindles and tubular upper control arms.
Click to expand...



Interesting, I had a '70 Pontiac Lemans Sport Convertible, never did any cage work, but I did have a Global West front end setup on it, and disc brake conversions....as I recall the spindles came from a '80 Caddy, installed a quicker steering box too, silly car did ok, for the '79 Firbird 15x8 wheels on it only 245 60 15 rubber might have been 70-15 rubber sold it almost 15 years ago, pardon my memory....


:beer:
 
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