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How do you keep the C3 from getting light above 120mph?

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How do you keep the C3 from getting light above 120mph?

 
Old 04-25-2013, 10:17 PM
  #181  
dmaxx3500
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once you get past 155mph,it will settle down
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Old 04-25-2013, 10:26 PM
  #182  
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Originally Posted by colesweat View Post
What is a termination box?
While I can't argue with the accuracy of BillCarson's post, I'll just stick to the automotive version of a termination box.


An exhaust termination box is just a large volume (surge tank) for the exhaust to dump into (in lieu of open headers) so that negative pressure waves can reflect back into the still open exhaust valve to help scavenge the exhaust gas out of the cylinder in an effort to increase the engine's volumetric efficiency. There's formulas (involving RPM, exhaust temperature, wave speed through a gas, blah, blah, blah) to arrive at the correct volume and location, and much of that gets thrown out the window due to the lack of packaging/space options under a Corvette. So, you do your best to fit what you can where you can.
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Old 04-26-2013, 04:36 AM
  #183  
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lots of cool pics and good ideas here. really like that front splitter on Bee Jays car along with the hood mods. managed 145mph at Road America last summer now have taller tires for the rear and a higher chip in msd so maybe 150 this year, which is my goal. can't figure out to post pictures here but check my garage and look at the hood mods on the blue car. Openings in front, middle and rear.
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Old 04-26-2013, 05:12 PM
  #184  
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Originally Posted by terrys6t8roadster View Post
lots of cool pics and good ideas here. really like that front splitter on Bee Jays car along with the hood mods. managed 145mph at Road America last summer now have taller tires for the rear and a higher chip in msd so maybe 150 this year, which is my goal. can't figure out to post pictures here but check my garage and look at the hood mods on the blue car. Openings in front, middle and rear.
http://forums.corvetteforum.com/c3-g...irections.html
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Old 04-26-2013, 06:02 PM
  #185  
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I was coming home a few weeks ago from a run with the C5-6 guys... and so the road opened//...... in 5th i cruised effortlessly at 150... and felt pretty good.... its more so the steering.... I wish it felt ... not tighter, its tight.... wish my wheel was more difficult to turn from side to side, its to easy. this gives the car the feeling of being light.
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Old 04-26-2013, 08:17 PM
  #186  
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Correct me if my memory fails me, but IIRC you still have power steering, no? I can attest that converting to manual does indeed improve road feedback, where the PS filters out much "information" you just never receive at the steering wheel.
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Old 08-29-2013, 11:19 AM
  #187  
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ok... building a new engine.... will have more hp then common sense...

so question, for thoes that have gone over 140mph, what is the fastest you have gone?

I was thinking of doing one of thoes 1 mile top speed runs they have on shut down runways, but... dont want to disenagrate and die at 160+
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Old 08-29-2013, 12:46 PM
  #188  
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Originally Posted by pauldana View Post
so question, for thoes that have gone over 140mph, what is the fastest you have gone?

I was thinking of doing one of thoes 1 mile top speed runs they have on shut down runways, but... dont want to disenagrate and die at 160+
I don't think that the standard C-3 vette is safe or even capable of higher speed driving without exstensive mods. Look at the modern NASCAR sprint cup cars going down the straights at 200 mph. The front splitter/ air dam is just skimming and sometimes even scraping the pavement.

C-3's have two major flaws: Way too quick of steering ratio in our steering box. I found it very hard to hold my Vette steady in one lane in my first attempt at open road racing in the 92 mile "Silver State Classic".

I thought i had my ducks in a row with the VB&P street slolam setup with 550# one inch shorter springs, extended chin spoiler and 25.7 inch diameter front 17 inch high speed tires to get the front end air dam right down on the road.

Out in practise runs with the 190 mph late model Vettes my short comings became disturbingly apparent. The turbulance when one of these guys passes you or in the wake of attemping to stay in their draft is unnerving. Our steering is way too vague. My Vette would shake from side to side in the other cars wind blast and changing cross winds on the course.

So I went to the QA-1 semi coil over front for height and spring adjustability. The rear I already had a 500+ inch pound steel with koni adjustable sport shocks.

The Bonneville guys run super slow steering ratios like 20:1

I did the open road racing and Bonneville speed week because I could. It became how much money do you want to throw into a very specialized c-3. It is better to just say that I've been there and done that if it is not your passion.
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Old 08-29-2013, 01:03 PM
  #189  
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Originally Posted by pauldana View Post
ok... building a new engine.... will have more hp then common sense...

so question, for thoes that have gone over 140mph, what is the fastest you have gone?

I was thinking of doing one of thoes 1 mile top speed runs they have on shut down runways, but... dont want to disenagrate and die at 160+
i've been 140 with no issues. car goes straight and i'm in complete control. Stock suspension setup
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Old 08-29-2013, 01:13 PM
  #190  
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140 is fine... im talking speeds of 160+ now...
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Old 08-29-2013, 02:47 PM
  #191  
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I've seen well over 160 in a near factory '69 L-88 with Hooker sidepipes and no baffles on Goodyear Blue Steaks. Talk about loud as that thing screamed at 7200 RPM's in 4th and pulling hard... I'm still grinning!
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Old 08-29-2013, 03:04 PM
  #192  
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Originally Posted by CaseyJones View Post
I've seen well over 160 in a near factory '69 L-88 with Hooker sidepipes and no baffles on Goodyear Blue Steaks. Talk about loud as that thing screamed at 7200 RPM's in 4th and pulling hard... I'm still grinning!
Like I have said early on here and elsewhere, do not believe the speedo, believe the GPS, ......


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Old 08-29-2013, 04:42 PM
  #193  
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well over 160mph with factory setup????? you are very brave.... and mrvette is probably correct... well over 160mph on a stock C3 is, well...... you have a one of a kind...

with all the work i have done to mine, still at speeds over 140 its just not right... like George said...

I don't think that the standard C-3 vette is safe or even capable of higher speed driving without exstensive mods. Look at the modern NASCAR sprint cup cars going down the straights at 200 mph. The front splitter/ air dam is just skimming and sometimes even scraping the pavement.
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Old 08-29-2013, 05:08 PM
  #194  
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Originally Posted by pauldana View Post
well over 160mph with factory setup????? you are very brave.... and mrvette is probably correct... well over 160mph on a stock C3 is, well...... you have a one of a kind...

with all the work i have done to mine, still at speeds over 140 its just not right... like George said...

I don't think that the standard C-3 vette is safe or even capable of higher speed driving without exstensive mods. Look at the modern NASCAR sprint cup cars going down the straights at 200 mph. The front splitter/ air dam is just skimming and sometimes even scraping the pavement.
There you go, you NOT driving it in/out of your own driveway much less over sewer caps, intersections, and sudden stops.....

may welding the suspension in front??? yeh, man, just about what it would take.....I find the comments about wide ratio steering being required at high speeds, I put in a rack to get some handling outta the beast, can't imagine living with stock steering after a dozen years now....but I not a racer....just trying to get HONEST performance increases, but need keep it affordable, and DO able by ME.....

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Old 08-30-2013, 12:12 AM
  #195  
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Check out the C2 section as a guy from Finland just completed his third attempt at breaking 200 mph in the standing mile. He is running a 650 hp SBC and hits 174 mph on motor and running nitrous to hit 200. His best attempt so far has been 196. He is running a small front air dam and has some under-carriage mods to keep the car stable.

Most C5 and C6 experts say it takes 750-800rwhp to hit 200 in the mile. A Z06 broke 200 recently with 675rwhp. The standing mile has a lot of appeal (my opinion), and the safety requirements dont force you to build a dedicated race car.
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Old 08-31-2013, 10:19 AM
  #196  
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Had our 69 mostly stock c3 some were over 160, the car is completely out of control with no turns, the steering it quick because the car is leaving the ground - eating up 3 lanes, now getting down to 120 it is not bad, still light. I think you would have to do a lot of work to the aero of this car to keep it on the ground. I don't think it is worth it to destroy maybe the best looking car ever made, just to go 160 - If you need 160 plus buy a 2014 Stingray - Just saying
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Old 09-04-2013, 10:39 PM
  #197  
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Originally Posted by uxojerry View Post
Check out the C2 section as a guy from Finland just completed his third attempt at breaking 200 mph in the standing mile. He is running a 650 hp SBC and hits 174 mph on motor and running nitrous to hit 200. His best attempt so far has been 196. He is running a small front air dam and has some under-carriage mods to keep the car stable.

Most C5 and C6 experts say it takes 750-800rwhp to hit 200 in the mile. A Z06 broke 200 recently with 675rwhp. The standing mile has a lot of appeal (my opinion), and the safety requirements dont force you to build a dedicated race car.
That is a cool C2 great thread....

200mph in a C3 would be pretty scary...

Originally Posted by colesweat View Post
Had our 69 mostly stock c3 some were over 160, the car is completely out of control with no turns, the steering it quick because the car is leaving the ground - eating up 3 lanes, now getting down to 120 it is not bad, still light. I think you would have to do a lot of work to the aero of this car to keep it on the ground. I don't think it is worth it to destroy maybe the best looking car ever made, just to go 160 - If you need 160 plus buy a 2014 Stingray - Just saying

if its stock gearing, it was probably around 140... our speedos suck, all of them read high i think...

I remember having my stock C3 up there at around 130+... floated like a boat
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Old 09-13-2013, 01:19 PM
  #198  
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I just read the Nov 2013 issue of Vette about the Sundowner C3 Corvette. If You want to run 251.838 MPH with a Stock body all You need is some Lead. Lots of it. I found it an interesting article.
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Old 09-13-2013, 05:17 PM
  #199  
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Originally Posted by Gale Banks 80' View Post
I just read the Nov 2013 issue of Vette about the Sundowner C3 Corvette. If You want to run 251.838 MPH with a Stock body all You need is some Lead. Lots of it. I found it an interesting article.
I read that article also. We have always thought about lightening our cars. I understand in his case that doesn't work. Just seems odd to consider adding weight.
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Old 09-13-2013, 05:39 PM
  #200  
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Originally Posted by vetteguy22 View Post
I read that article also. We have always thought about lightening our cars. I understand in his case that doesn't work. Just seems odd to consider adding weight.
You lighten a car to increase its cornering ability. If you're just going in a straight line and the rules won't let you change the aero shape of the front end, a bunch of lead ballast will keep the front end down.

(I believe Porsche did a similar thing on the front of the original 911 to add understeer to counter the rear weight bias of that car.)
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