3.8L V6 Automatic, any tips? - Page 4 - Fuel Economy, Hypermiling, EcoModding News and Forum

ktaylor · 03-31-2011, 11:49 AM

Yeah thanks ShadeTree, I forgot about the fuel pumps being in the tank. A friend of mine just had his burn out and its around a g note to get it fixed. Not worth the .05 or whatever mpg I calculated.

comptiger5000 · 03-31-2011, 01:05 PM

Then again, if you like the car enough to want to custom up a FWD 3.8l manual tranny, you might as well just convert it to RWD (would probably be cheaper), as you can then use any tranny that will bolt up to the engine and fit in the car.

nemo · 03-31-2011, 06:35 PM

Quote:

Originally Posted by ktaylor

What do you mean by "do it correctly"? My car has to go up to 47mi to downshift and I have the same 0.7 4th gear and 3.05 final drive.

What I meant by that was if I use too much power or too little power I am not be able to get the low shift point. Also don't worry about what works on my car you need to find what works for you. By the numbers it looks like you doing good you are above EPA.

Quote:

Originally Posted by ktaylor

What rpm's are you holding when it drops to 4th? It must be close to 1100 or so.

I will recheck the numbers and post them the next time I have the car out.

rmay635703 · 03-31-2011, 08:05 PM

Quote:

Originally Posted by comptiger5000

Then again, if you like the car enough to want to custom up a FWD 3.8l manual tranny, you might as well just convert it to RWD (would probably be cheaper), as you can then use any tranny that will bolt up to the engine and fit in the car.

There was a 4sp overdrive transverse manual transmission for GM related vehicles (New Process 833 A-body (MY6 RPO)), it was in the same family as the old Sm465. Would be quite neat to see one in a Brick.

99LeCouch · 03-31-2011, 08:36 PM

The old-style 4T65's need to get to 47-48 mph to shift into 4th with TCC lockup. My RPM's go from 1800 RPM to 1200 RPM at 48 mph.

The fuel pump is about $200 with the sender included. Even dropping the tank with labor shouldn't be more than $600 or so.

And, getting the 3800 into 4th at 50-55 mph is about the most efficient way to drive these cars. I don't see a lot of difference between 50 and 55 mph on my ScanGauge.

For those 3800 V6-equipped cars, get a ScanGauge or an UltraGauge. It's the best way to wring the absolute utmost fuel economy from these cars.

ktaylor · 03-31-2011, 11:38 PM

I wanted to thank everyone on here. I just broke the 30 mark on my last fuel up. I had a really nice drive home from school last night (8:00-9:30) and I could instantly tell it was good for the mileage. I didn't expect a 31 mpg tank though!

Thanks for all your replies.

comptiger5000 · 04-01-2011, 08:08 AM

Congratulations! With a little more practice, maybe you can hit 32

ktaylor · 04-01-2011, 12:06 PM

Yeah that would be something. Maybe I should just change when I'm commuting to less traffic scenarios, even though that would mean leaving at 5-5:30 am and coming home around 7...ugh. That would probably do it though. I'm pretty proud of my 48% above epa fill up though.

ktaylor · 04-01-2011, 12:07 PM

Quote:

Originally Posted by 99LeCouch

For those 3800 V6-equipped cars, get a ScanGauge or an UltraGauge. It's the best way to wring the absolute utmost fuel economy from these cars.

What mileage do you get out of your Lesabre?

99LeCouch · 04-01-2011, 02:28 PM

Quote:

Originally Posted by ktaylor

What mileage do you get out of your Lesabre?

This winter I was getting 25 mpg in mixed small town and rural highway driving. Right now it's up to 27-28 mpg with the warmer weather and my all-seasons put back on. I'm hoping to see 29-30 mpg in the summer. It won't get much better because much of my driving is on a set schedule for work.