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02-20-2018, 10:39 AM | #1 |
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Mph
Running super street. Will I gain any mph going from a 4.86 rear gear to 4.30? 950 hp car trapping about 140-142ish
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02-20-2018, 12:13 PM | #2 |
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Re: Mph
Difficult to say. I would doubt it, as the car will have a more difficult time getting up to speed when it comes off the stop.
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02-20-2018, 01:25 PM | #3 |
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Re: Mph
I agree with Lenny5160. Converter lockup will change dramatically, It will slip more. Maybe try the 4.56 gear.
Dan
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Dan Foley SC 4698 |
02-20-2018, 01:35 PM | #4 |
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Re: Mph
My thoughts too. Was getting suggestions from others that I would pick up alot but I'm not sold on it
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02-20-2018, 02:15 PM | #5 |
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Re: Mph
Rpm=mph
That’s the short version
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KEITH MAYERS 2 X somebody many X nobody Last edited by Keith 944; 02-20-2018 at 02:17 PM. |
02-20-2018, 02:36 PM | #6 |
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Re: Mph
Hear lots of good things about the APD Max Speed....seems like better way to go if you don't mind changing to a different setup. There's another thread on throttle stops which got me doing some research.
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Jim Carter 2340 Super Stock 2340 SST/2340 Stock Set another place at the table |
02-21-2018, 10:45 AM | #7 |
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Re: Mph
That is a 12% change in gear ratio . not taking into account the probable loss of converter efficiency that will occur , that's a nearly 1000 rpm drop in trap rpm.
Not to mention the loss of reaction time and loss of acceleration coming off the stop. I'd be talking to your converter guy , maybe looking at a lower stall higher efficiency converter using the existing gear. You didn't mention what your trap RPM is . ....Is that a concern that it's too high ?
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02-28-2018, 04:10 PM | #8 |
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Re: Mph
Mine did.
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06-01-2018, 03:29 PM | #9 |
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Re: Mph
I'm a little confused here. What does your car weigh? 950 HP and only 142 mph? Something doesn't calculate. I had a Super Street car that went 148-150 with 875 HP.
Car weighed 3000 lbs. (67 Cuda). I used 4.56 gears and hit the finish at about 7600 rpm. Engine made peak power at 7300. |
06-09-2018, 11:15 PM | #10 |
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Re: Mph
I have a 505 bbc in a 70 chevelle that made 860 on stinnets dyno a few tears ago and it only runs 137,139 best. 4.88 gear 14.5 32 tires. 3150 with me
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