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Discussion Starter #1
1. what should your 1/8 time be to run a 13's in 1/4 mile?
2. what should your 1/8 time be to run a 12's
3. what should your 1/8 time be to run 11's


the reason i ask is i dont have a roll cage in my car. i dont want to go to the dragestrip and only get one run in. and get kick off for not being up to code. i will give it my all when its my last run. so i plan on given it all to the 1/8mile,untill my last run.
 

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For a rough estimation using an average car you can figure that the 1/4 mile elapsed time is about 1.56 times the 1/8 mile time. 8.50 in the 1/8 should get you close to 13.2 seconds, 7.50 in the 1/8 would be 11.7, etc.
 

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The only one I know for sure is that the 6.35 and 9.99 require the same cage.

Adam
 

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Discussion Starter #4
well i went to the dragstrip. i am happy but i know i could get more out of it.
i ran a best at 12.147 at a 114.22 mph 60 ft.= 1.87 1/8th = 7.872 at 92mph . so what would you do to reach high 11's. with out messing with the motor..
heres my combo,3500pound 70 chevelle. bbc cam range 3000-6500 , th400. 2500 stall manual valve body, 12 bolt posi 3.26 gears with a 29 in slicks .. should i install lower gears like 3.93 4.10 etc, would a smaller slick work. would a higher stall work. :(
 

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You have any idea what RPM you are crossing the line at?

If you're way under your top RPM then gearing and/or smaller dia slicks might help.

Might be able to borrow someone's shorter slicks to test. Would be easier than switching gears to make sure.

-Stephen
 

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http://home.earthlink.net/~whshope/id4.html

chevelle4542speed said:
well i went to the dragstrip. i am happy but i know i could get more out of it.
i ran a best at 12.147 at a 114.22 mph 60 ft.= 1.87 1/8th = 7.872 at 92mph . so what would you do to reach high 11's. with out messing with the motor..
heres my combo,3500pound 70 chevelle. bbc cam range 3000-6500 , th400. 2500 stall manual valve body, 12 bolt posi 3.26 gears with a 29 in slicks .. should i install lower gears like 3.93 4.10 etc, would a smaller slick work. would a higher stall work. :(
Try this link from the home page of pretty sharp engineer Billy Shope... and then you can do some of your experimentation on electronic paper. Smaller slick, lower gears, higher stall all are directionally correct... but the last two are more work..
 

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Are you saying that you pull up to the start line at 3500 pounds in a 70 Chevelle??????? Is this a gutted race car?

Quarter to eighth conversions vary depending if the car is geared for the eighth or geared for the quarter.

So what's your engine question?
 

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I think some numerically higher gears would probably get you into the 11's. If your cam is rated for 3000-6500 RPM, a 3000-3500 stall should help out a lot also. I think those two things togather would easily get you an 11 second car. Do you happen to know the specs of your cam?

Adam
 

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Discussion Starter #11
yes , 305h series magnum comp cam cam is ratef to 3000-6800 but i only spin my motor to 6500. .050 = 253. .575 lift 781 heads. pump gas.
 

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Discussion Starter #12
xntrik said:
Are you saying that you pull up to the start line at 3500 pounds in a 70 Chevelle??????? Is this a gutted race car?




no this is not a gutted race car. i have full interior, pulled the passenger seat out cause i only had one bolt holding it :nono: drive it every weekend night.
 
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