What happened

volareandgtcat

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Thanks barbee .......... you know with all this work, I never looked at the air filter .... it's way over due for a change .. that'll be the next thing on my list.
Nice AJ/ ... gotta luv the stories
 

AJ/FormS

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318s don't like 2.45/2.2 much either,
they only suffer them with the A998/999s
Once the tranny goes into 3rd/loc, they often barely have enough power to cruise the flat,level,hiway,with that 2.45
First gear does ok, the ratio is about the same as a A904 with 2.76s.
Second is a bit steeper, seeming like 2.60s
Drive is like,well, 2.45s
2.2s suck for getting up to speed. But they cruise ok at 85mph, if you can get there,lol.
Here is a comparo; using final drive ratios
First this is what a teener likes; 7.91-4.68-3.23 This works pretty good. KD @55 will get you about...... 3570rpm
Then what most got............... 6.76-4.00-2.76 This is barely adequate, KD will get you about.............3050
Then the A998/2.45................ 6.71-3.77-2.45 You need a lot of room to pass,a lot!KD is about........ 2875
And then,oh dear..................... 6.03-3.39-2.2 Forget passing,take a pill,settle down.KD is about........2585

Comparing to the 3.23s ;
The difference in starter gears from 7.91 to 6.03 is 76% So it's like taking 24% of the engines torque away. That's like dropping a cylinder, POOF!, gone.You now have about 242 cubes left
Second gear is 3.39/4.68=72%, so 28% is now gone; more than a cylinders worth. Now;229 cubes
Top gear is 2.2/3.23=68%, so now 32% is gone. That's like 1/3 of them just went on vacation. You are left with 216 cid. 100cubes AWOL.
 
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BudW

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To demonstrate AJ/FormS’s numbers, refer to this thread:
Performance Meter
Post # 29 and post # 30

The only difference between the two cars is Lean Burn (which shouldn’t matter much), gear ratio and maybe some weight difference between the two cars – but I don’t think enough weight to matter, either.

I do have an 8¼” differential with 2.94 gears to install in the 5th Ave (one of these days), and have plans on posting updated results on it soon, but I expect the two cars to run closer to the same time, then.

That 2.2 ratio is for the birds, err, for the worms (and they can have it).
BudW
 

volareandgtcat

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Update .... mileage is up to 19 mpg. and I'm still waiting on the new air filter ... I might just break the 20 mpg. .... this is all city and county driving ... 20 min. into the city .. 20 min. stop-n-go .. 20 min. home. That's a usual trip for me.
 
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