Did I speak too soon?
 

I was just talking with a friend who's driving his mom's spare car, an 02 (I think) Buick Park Avenue while his car is in the shop. Anyway he's thrilled he's getting 24 MPG as reported by the onboard trip computer. I told him I could probably do over 30 if I was driving. Well, he's going to make the same trip later this week and he's challenged me to do it. I'm thinking bring the SG with me, air the tires up to 40PSI, a duct tape grille block, keep the speed under 60 MPH and DFCO whenever possible.

Now I'm starting to second guess myself. I'm sure I can do better than he's getting, but can I really get a Park Avenue to turn over 30 on the highway? Has anyone here tried to hypermile a late model Park Avenue?

-Jay

I dunno, the new super pessimistic rating is 27 mpg hwy, the old was 29, so if he's not getting 27 hwy the car has something wrong that needs fixing first. Then it should be possible to get 30 with tires at factory pressure and non-agressive driving, and prolly 35 with 40 psi and some light hypermiling technique

He does drive fast, and with the a/c on all the time... that could make up for the shortfall in highway mileage he experienced.

-Jay

Oh, and I forgot to mention... He weighs ~450 pounds, but I thought we've already determined that would not make a noticeable difference in fuel economy.

Well as long as you don't make him sit in the back and put it nose high :D

It makes a big difference in aggressive and city driving but of course, "momentum economy" type techniques will nullify it.

you can totally get 30mpg if you go a reasonably low speed with tires near the max psi, rarely using the brakes, and keeping rpms extremely low.

I don't know about the trip computers in the Park Avenues. My mom has a 99 with 12,500 miles on it. I took it up on to I-75 and it was showing between 35 and 38 mpg at 65 mph with the cruise on. When I was down there two weeks ago I did notice something interesting while under the hood. GM tipped back the radiator about 15 to 20 degrees.

On a highway drive you should be able to get an easy 28 maybe a little better without hypermileing and just driving the speed limit. (flat highway)

I get an easy 28 highway with a very peppy 3.1 L v6 cutlass. I get an easy 28 highway with a 07 Impala 3.5L v6, which is a larger car (not mine). I will be taking the Impala to Boston tomorrow and will check it out of curiosity. For sure the Boston traffic will make a difference once I get there so I'll check it for both city and highway. But it is mostly a highway drive down the entire length of the Mass Pike. Also I will be going over the birkshire mountains. I always go 68-70 whenever I make that trip. Everything makes a difference.

I did get unbelievable 34 with the Impala once on a rural 50 mile strip of flat road at 60mph (cruise control on) and no stop lights and no traffic in the middle of the night, but that won't happen again. But it is possible.

Anyway, depending on motor/tranny you should be able to get 28 easy on flat highway and under the right circumstances, might even approach 30.

I once drove one from Florida to Mass. I averaged just over 31 MPG, and I wasn't driving slowly either.

-BC

They did that to get a bigger radiator into the car without making the nose taller. They did that on the Fiero too.

-Jay

the buick stands a good chance of beating 30 with some hypermiler techniques. heck my car is rated pretty bad too but I'm over 32mpg so far this tank. I think you made a fair bet and you will take home the cash or bragging rites or at least make a believer out of your friend

I've got lunch riding on it... so for me that could be expensive if I loose!

-Jay

I don't know GM cars like I do Ford products, but my dad has a 1999 Mercury Grand Marquis with a 4.6L V8 w/od and he get about 28 mpg on the highway with it at 70-75mph using the a/c and c/c. It will get about 24 on local short trip driving. I don't think it should be any trouble at all to get 30 unless there is something bad wrong with the car. Road Warrior says the old EPA rating is 29 mpg so you only have to get less than 4% above epa if you drive 55-60 that shouldn't be a problem. How much of the trip is interstate driving and how much is stop and go?

LOL!

Has it got that magic 3.8L engine? :) I suspect you can get 30 hwy pretty easily, using the techniques you described.

Right now I don't know what engine it has. I'm pretty sure its a V6, but it could be larger than a 3.8. I figure if he got 24 on that trip, and 30 was a nice, round number. I now realize that if I do reach my goal I would have a 25% increase in mileage... with minor mods and careful driving. Another thing I should mention. The trip is from Sterling, Va (near Dulles airport) to Berkley Springs, WV. The drive will be mostly highway, but it will not be flat. Hills and mountains, which if I play my cards right means lots of DFCO.

-Jay

If it's a trip where you know the roads well enough and know where the long steep downhill grades are you might benefit by using neutral coasting over DFCO to prevent engine braking.

I haven't made the trip to Berkley Springs in about 2 or 3 years. Suffice to say that I won't be able to anticipate the road ahead. That being said I will be driving in hilly and mountainous terrain. I'm thinking DFCO as much as I can.

I also asked him what engine it has. He has the 3.8 V6 in it.

-Jay

Piece of cake with the 3.8L
I know people with this engine in the Riviera (no longer made) who get 30 on the hiway consistantly.

I know they've done a lot with that engine over the years. Its a dog in my Buick though.

-Jay

My 95 supercharged Riviera would get 27-28 on the highway at 70-75MPH with no hypermiling techniques.
That car would coast forever, must have been a fairly low CD. I had to relearn my timing to keep from coasting too close to the car in front of me when traffic slowed down.

regards
gary

Jay, you can do it or get real close with the park avenue.

I just got back from Boston per my prior post above and clocked 30.2 down and 29.9 back. Had the a/c on for the trip home for half way. Going through the mountains killed it a little. It went to 29.1 through the mountains and then after I hit flatter road, it creeped back up to 29.9. Had the cruise on 70 part way and used my foot part way. Pretty much maintained 70 all the way. RPM's were 1,900 at that speed. Didn't do anything elce to help gas mileage except I am not an aggressive driver.

Is it supercharged or naturally aspirated? I used to have a 1997 Grand Prix with the 3.8 supercharged engine, and would regularly see 31-32 mpg on highway trips without trying. The supercharged cars had a 2.93 final drive ratio compared to the NA's 3.29, so I guess that helps when you are not getting on it all the time. :D

Edit: Just read that you were going to Berkeley Springs, WV. I used to live there! A nice little town, and tons to do in that area if you are into outdoorsy type stuff. Head down to Seneca Rocks and Dolly Sods (a few hours away) if you are going to be there a while. Beautiful area.

I don't believe it is a supercharged model.

-Jay

Well, we went today. I didn't drive. My friend insisted on driving. I now know why he gets such poor mileage. Driving 80 MPH through mountain passes is not only bad for FE, but its also dangerous and scary for your passengers. He would then speed up to prevent people from passing him, then slow down when they could no longer pass. To make matters worse, he would then get upset whenever he saw others driving as he did, and blamed it on their SUV's. I have determined that I will never ride with him driving again. It is just too scary.

-Jay

Sounds like he forfeited the contest. He must have figured if you drove it would take much longer to get there because you were going to be driving slower for FE. You should make him buy you lunch.

Yeah, but driving the speed limit my GPS calculated the trip would only take 2 hours. I'm shocked he doesn't have a huge pile of speeding tickets.

-Jay

I am dissapointed. I wanted to hear about you actually getting 30mpg with the park avenue.

Sounds like a relative of mine that I do not ride with either..

Yeah, well that was the first time I have ever gone more than a mile or 2 with him driving. In the past if we went anywhere we always took my truck because it usually involved hauling or picking up something big. I was excited about the prospect of showing him how good that car can do, but he's perfectly content driving the car the way he does and getting 24 MPG.

I was scared at times with him going as fast as he was, and he really wasn't doing a good job of keeping the car in its own lane. When it came time for him to parallel park I just closed my eyes and told him to tell me when it was over.