20b question

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Old Oct 22, 2006 | 05:31 AM
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20b question

i was thinking if i got the 20b in a 86 fc na how much would it throw off the weight of the car?????
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Old Oct 22, 2006 | 06:04 AM
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Originally Posted by Red_Rabbit86
i was thinking if i got the 20b in a 86 fc na how much would it throw off the weight of the car?????
Not much. According to Peter Farrell, the 20B weighs only 100 lb. more than the 13B. In my car, the weight distribution is 51% front and 49% rear.
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Old Oct 22, 2006 | 06:23 AM
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http://www.cris.com/~Asam/Part3.html

The only other problem is the heat. Come Thanksgiving, I know how to prepare the turkey: put it on the floor on the passenger's side....

Taking the twisty's with the 20B roaring in my ears was the sort of Independence Day celebration that gives meaning to "life, liberty and the pursuit of happiness". Gas mileage suffered dramatically. ;-)
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Old Oct 22, 2006 | 05:08 PM
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i read the story and heard you say you only got 12 mi to the gal is it possable to get anything better?
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Old Oct 22, 2006 | 05:45 PM
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Originally Posted by Red_Rabbit86
i read the story and heard you say you only got 12 mi to the gal is it possable to get anything better?
You're going to throw $10K dollars into this swap, who the hell cares about fuel milage.
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Old Oct 22, 2006 | 06:10 PM
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Higher gearing and good tuning should get you much better mileage than 12MPG on the freeway. The 20b doesn't need that low of a ratio to accelerate quickly anyways.
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Old Oct 22, 2006 | 06:22 PM
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fuel

At 60mph highway i am at 25 to 26mpg, with street port.
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Old Oct 23, 2006 | 05:41 AM
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Originally Posted by Red_Rabbit86
i read the story and heard you say you only got 12 mi to the gal is it possable to get anything better?
After adding a wide-band O2 sensor, which provides feedback directly to the TecII, I'm getting 15.5 mpg on my daily commute. I haven't taken it on a long drive, yet, so I can't give a current highway mileage figure. Without the wide-band, I got 16.5 mpg on a trip to Florida, as well as on a trip to Canada. I'm hoping that I could get 18 - 19 mpg now.

The answer posted by slo is good advice. I have a T-II differential (4.10 : 1), and I could easily get by with a 3.7 : 1 ratio or even a 3.3.
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Old Oct 23, 2006 | 05:42 AM
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Originally Posted by teachermechanic
At 60mph highway i am at 25 to 26mpg, with street port.
What rearend ratio are you using?
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Old Oct 23, 2006 | 11:16 AM
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Originally Posted by Attila the Fun
What rearend ratio are you using?
Stock with 5 speed. At 14.7 to 15.0 A/R
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Old Oct 23, 2006 | 12:56 PM
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Good luck finding taller diff ratios for a TII rearend.
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Old Oct 23, 2006 | 01:07 PM
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Originally Posted by Red_Rabbit86
i read the story and heard you say you only got 12 mi to the gal is it possable to get anything better?
mine got 19.9 on the highway, 14-16 in mixed driving. if you drive it hard though, single digit mileage would be really easy
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Old Oct 23, 2006 | 01:12 PM
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Not a 20B. but for refrence my tired 13b-re swapped FC gets 22-23 with the haltech set for closed loop 14.8-1 at 80 MPH.
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Old Oct 23, 2006 | 01:21 PM
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Originally Posted by RX-Heven
Good luck finding taller diff ratios for a TII rearend.
i've read that racing beat can make any ratio you want, i have no clue what it would cost though.
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Old Oct 23, 2006 | 08:28 PM
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[QUOTE=Attila the Fun]After adding a wide-band O2 sensor, which provides feedback directly to the TecII, I'm getting 15.5 mpg on my daily commute. I haven't taken it on a long drive, yet, so I can't give a current highway mileage figure. Without the wide-band, I got 16.5 mpg on a trip to Florida, as well as on a trip to Canada. I'm hoping that I could get 18 - 19 mpg now.
QUOTE]

The tec 2 does not have sequential fuel injection does it?
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Old Oct 23, 2006 | 09:45 PM
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if racing beat makes it, you'll have to sell the car and refinance your house to afford it.
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Old Oct 24, 2006 | 06:22 AM
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Originally Posted by teachermechanic
Stock with 5 speed. At 14.7 to 15.0 A/R
That's astounding. Nice job of tuning.
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Old Oct 24, 2006 | 06:24 AM
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[QUOTE=CMonakar]
Originally Posted by Attila the Fun
After adding a wide-band O2 sensor, which provides feedback directly to the TecII, I'm getting 15.5 mpg on my daily commute. I haven't taken it on a long drive, yet, so I can't give a current highway mileage figure. Without the wide-band, I got 16.5 mpg on a trip to Florida, as well as on a trip to Canada. I'm hoping that I could get 18 - 19 mpg now.
QUOTE]

The tec 2 does not have sequential fuel injection does it?
I actually have two TecIIs. The second one handles the trailing plugs and injectors. At some point, I plan to upgrade to a single Tec3, which has built-in support for a 20B.
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Old Oct 24, 2006 | 11:06 AM
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Originally Posted by Attila the Fun
That's astounding. Nice job of tuning.
It's more like i am at 60mph, but also tuning is with Steve K.
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