Converter and mph?
10-28-2006, 09:57 AM
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Converter and mph? I have 3.73 gears a glide and 28" M/T street radials.I'm trapping 143 on the limiter (7200rpm).According to a gear calculator I should be able to go 161mph.I know the converter slips some but that much?
I called the converter company and they told me put 4.10s in that would actually help my problem?????I questioned him but he was sure that would work.I suggested I put 26" tires on and he said no thats not the same I have to put 4.10s in.What do you guys think?Put 4.10s in?Put 3.50s in or work on the converter?
I called the converter company and they told me put 4.10s in that would actually help my problem?????I questioned him but he was sure that would work.I suggested I put 26" tires on and he said no thats not the same I have to put 4.10s in.What do you guys think?Put 4.10s in?Put 3.50s in or work on the converter?
10-28-2006, 12:33 PM
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My car ran 145 and the slide rule said 161. The smaller size, the more big end slip.
Why in the hell would more gear, work?? You will be hitting the chip sooner, not later.
I personally have decided to switch the 8" for a 9 1/2" in my slow car, just to get less slip. The fast car uses a special 2 pc 10".
I would go bigger tire if it fits, or less slip converter. Is your motor not strong enough to rpm that high?? just change the chip, 143 should be a 9 second MPH.
Good luck, be careful.
Why in the hell would more gear, work?? You will be hitting the chip sooner, not later.
I personally have decided to switch the 8" for a 9 1/2" in my slow car, just to get less slip. The fast car uses a special 2 pc 10".
I would go bigger tire if it fits, or less slip converter. Is your motor not strong enough to rpm that high?? just change the chip, 143 should be a 9 second MPH.
Good luck, be careful.
10-28-2006, 02:23 PM
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Originally Posted by mrdragster1970
My car ran 145 and the slide rule said 161. The smaller size, the more big end slip.
Why in the hell would more gear, work?? You will be hitting the chip sooner, not later.
I personally have decided to switch the 8" for a 9 1/2" in my slow car, just to get less slip. The fast car uses a special 2 pc 10".
I would go bigger tire if it fits, or less slip converter. Is your motor not strong enough to rpm that high?? just change the chip, 143 should be a 9 second MPH.
Good luck, be careful.
Why in the hell would more gear, work?? You will be hitting the chip sooner, not later.
I personally have decided to switch the 8" for a 9 1/2" in my slow car, just to get less slip. The fast car uses a special 2 pc 10".
I would go bigger tire if it fits, or less slip converter. Is your motor not strong enough to rpm that high?? just change the chip, 143 should be a 9 second MPH.
Good luck, be careful.
I would raise my limiter but I dont think there is any power up there.This is a nitrous car.
Do you think a 3.50 gear would hurt me.Cant go with a bigger tire.
10-28-2006, 02:48 PM
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Ok,! 3.73's + 28" tire+7200rpm=160.8 MPH, That's always true regardless of what color your car is, how heavy or what engine you have , that being said, sounds like you have too much convertor slippage, about .46:1 = 900rpm slippage, that's alot. A decent convertor has about 500rpm tops which is .25:1 ratio increase, It's possible your blowing through the convertor when using the nitrous! Check the MPH vs RPM without the nitrous on! Going to a 4.10 would only lower the MPH@7200 rpm, I can't see how that gear change would make the convertor more efficient (sometimes more rpm would tighten the convertor up, but your already spinning enough!) My friend runs a 74 Camaro 3400#'s 406 SBC 3.73's, 28" tire, about 4500 Convertor 10",TH400 and he goes 8.74@155mph @7000-7300rpm through the traps. Check with another convertor company see what they think! I'm defitnitely not an expert in/on convertors, but have had my share of experiences! Good Luck!
10-29-2006, 02:50 AM
#5
This is a good thread and I hope this one gets plenty of input like you guys have already added.
Here's the TCI calculator and I show that he has 88.9% efficiency with that converter going through the traps. Is that good, bad or normal? What is considered very good efficiency going through the traps?
http://www.tciauto.com/Products/Tech...culators.asp#4
What kind of gains could be expected in his case if he were at say 94% efficiency, but had very good 60ft times? Is it possible to "have it all"?
Here's the TCI calculator and I show that he has 88.9% efficiency with that converter going through the traps. Is that good, bad or normal? What is considered very good efficiency going through the traps?
http://www.tciauto.com/Products/Tech...culators.asp#4
What kind of gains could be expected in his case if he were at say 94% efficiency, but had very good 60ft times? Is it possible to "have it all"?
But...
10-29-2006, 08:59 AM
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Originally Posted by Old Geezer
that 28" tire is no longer 28" @ 143MPH.
Tire growth will seriously affect the slip calculations.....
Using your values, and doing the calcs, using a 30" tire, the slip is over 20%. That is WAAAAY too loose.
Tire growth will seriously affect the slip calculations.....
Using your values, and doing the calcs, using a 30" tire, the slip is over 20%. That is WAAAAY too loose.
I have a set of 28 10.5 15 M/T slicks but they grow so much they start rubbing at about 135.
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10-29-2006, 12:45 PM
#8
Try..
Originally Posted by ls2formula
Yes,but this was on radials.I do not think radials will grow 2 inches will they?
I have a set of 28 10.5 15 M/T slicks but they grow so much they start rubbing at about 135.
I have a set of 28 10.5 15 M/T slicks but they grow so much they start rubbing at about 135.
Check out that convertor! 
11-02-2006, 08:01 AM
#13
Im a turbo car with the same rear gears.. 3.73's and a Glide using a Neal Chance Converter.... on 28" Hoosier slicks i was off the Rev limiter that last 150 ft and still did 150.58 mph... that was a 1.45 60'.... 7K RPM's...
Now on my 28" radials i have done 144mph with a crappy 2.1 60' spinning.....
I dont know what they hell the guy was talking about going with a 26" tall tire or 4.10's.... he's nuts...... Im going down to 3.54's in my new rearend...
Now on my 28" radials i have done 144mph with a crappy 2.1 60' spinning.....
I dont know what they hell the guy was talking about going with a 26" tall tire or 4.10's.... he's nuts...... Im going down to 3.54's in my new rearend...
