Jump to content

Real world gas mileage 3800


Guest sintid58

Recommended Posts

Guest sintid58

I made my first round trip back to South Dakota this weekend. The Impala has a 3800 in it and averaged on the trip 30.75 MPG over 1227 miles of mostly interstate driving. I didn't drive over 75 but the computer showed overall I averaged 68.75 MPH on the entire trip. Not too bad for a gas guzzeling noisy old engine.

Link to comment
Share on other sites

That mpg sounds like it's "in the ballpark" for that vehicle platform and engine combination. The last gen LeSabres had a little taller gearing so they would do a little better in highway mileage . . . taking about 82mph to get to 2000rpm on the road.

I concur, not too bad for an antique-design engine with (gasp!!) pushrods rather than overhead camshafts and lots more "stuff" inside the motor.

In reality, the Buick 3800 is a fully contemporary and highly advanced engine assembly which produces sufficient power AND torque to be happy "loafing" along at very modest rpm levels on the road, yet yields highly respectable fuel economy and durability AND power while doing so. Of course, this situation's been like that for close to TWENTY YEARS!

Enjoy!

NTX5467

Link to comment
Share on other sites

Guest rlbleeker

Just got back from a 2200 mile drive in our '99 Riv and got about 27 mpg overall, even with all those windy Oregon roads. I think it would do quite a bit better if you could keep it around 65 mph (1500 rpm), it cruises with almost no throttle at that speed.

Link to comment
Share on other sites

Guest dabecker65@gmail.com

Shame to lose such an engine even though it is considered a technological "antique", all because it has pushrods...

Had a '99 Park Avenue that averaged 32 mpg from West Palm Beach to Kingsport TN - loaded w/ 2 persons & luggage - 70-75 mph on cruise including through the mountains in E. TN.

But, so it goes - years ago had a '55 Super 56R w/ 322 nailhead/Dynaflow and it was nothing for it to consistantly obtain 21-22 mpg at 65 mph. As I recall the '55 weighed in at around 4000#.

We'll miss the 3800...

Link to comment
Share on other sites

Unfortunately, all things sometimes have to come to an end. In the case of the Buick 3800 V-6, there are a couple of things I suspect figured into the mix.

First, the tooling is probably nearing it's replacement time. From one perspective, if you've got to replace the tooling, why not use the same money and do some changes and upgrades for a new product?

Second, as the Buick V-6 was originally from V-8 tooling, that means it's a 90 degree V motor, which is generally wider than the more recent (and sometimes more desireable) 60 degree V V-6s. Plus, by observation, many of the 60 degree V-6s have a more high-pitched sound (for a more Italian sound, it seems) rather than the lower frequency harmonics of the Buick 3800. BUT, in the Lucerne I rode in the other day, the engine was totally quiet.

In todays narrower cars, and possibly smaller cars in the future, the additional width of the basic engine (the Buick 3800) of a 90 degree V-6 versus a 60 degree V-6 can become significant.

Third, in the global marketplace, it seems that OHC engines are "in" and pushrod V-6s are "out". The Buick 3800 has already been replaced by the High Feature 3.6L DOHC V-6 in Australia a few years ago. The 3.6L V-6 is also more "exportable" to countries where pushrods went away many years ago, typically. I rememeber the kudos for the BOC Powertrain people when GM Holden decided to replace their Nissan engines with the Buick 3800s in the late 1980s, but global "times have changed", it seems.

Currently, many generations of younger people have grown up paying more attention to Mitsus and Hondas and such (which have awaard-winning V-6s in them--with OHC engine architecture). Even many bargain basement imports come with OHC engines as standard equipment. These will be "future buyers", hopefully, of GM and Buick products.

So . . . we end up with the Chevy 3.5L V-6 and its 3.9L variant--the High Value V-6 engines. When the Chevy 2.8L 60 degree V-6 engine family was expanded to become the Vortec 3.5L V-6, it gained enough power and economy to pretty much displace the Buick 3800 V-6 for many bragging rights . . . including fuel economy and power. The initial 3.9L V-6 had about the same power as the Chrysler 3.5L "Cammer" V-6--but using pushrods--and similar horsepower as the Buick 3800 SC V-6 (but not quite the same amount of torque).

The High Feature 3.6L OHC V-6 was designed with future needs in mind. One is "direct injection" rather than "ported" injection. If done correctly, this can be a big deal! More horsepower and better fuel economy doing it, plus lower emissions. It also has fwd, awd, and rwd capabilities.

I suspect that when the Buick 3800 is finally pulled from production, the engine choice with Buick will mirror those of Cadillac. High Feature V-6s and NorthStar V-8s, typically, other than having different engines for specific car lines' vehicles.

Just some thoughts,

NTX5467

Link to comment
Share on other sites

as you point out, the 90 degree angle resulted from being derived from a V8. It's not a naturally balanced layout for a V6 - the 60 degree has better fundamental balance.

Link to comment
Share on other sites

Guest dabecker65@gmail.com

All true gentlemen...but going from the sublime to the rediculous, imagine:

248 (4.1L) or 263 (4.3L) straight 8 updated with direct injection, PCM, roller cam, tuned intake & exhaust, supercharged, laid over for vertical clearance, etc set up for transverse FWD - all in a "wide track" platform. Heck, why not a 320 that could come with wide load placards in place of bumpers...talk about "torque steer"!

Oh, right - it was all about real world stuff wasn't it?

Link to comment
Share on other sites

Don't forget about fully electronic ignition so you can delete the distributor mechanism completely, plus being sure to lay it over so the spark plugs face the front of the vehicle. And, if we're going to "dream", then let's recast the block and cylinder head in aluminum and also use fancier materials to take rotating mass out of the guts of the motor (i.e., rods, pistons, piston pins). Plus knock sensors so the compression ratio could be pretty close to 10.0 to 1 and still run existing regular fuels, AND be compatible with the higher octane rating of E85 fuels.

Just some thoughts,

NTX5467

Link to comment
Share on other sites

Guest dabecker65@gmail.com

All great ideas - except facing the plugs to the front where you can get at them is apparently a direct contradiction to modern engineering theories - takes all the challenge out of servicing - what "fun" is that?

Link to comment
Share on other sites

The best gas milage with my Park Ave was from Bowling Green Ky to Flint,573 miles, cruise set on 60 , just to check gas milage.Only one stop,but not for gas, 34.41 MPG Norb

Link to comment
Share on other sites

When my 85 Park Avenue was still alive it would consistently get 32 on the highway between Denver and Chicago. It was turned into a convertible by a semi turning left from the wrong lane. My current 1999 Olds 88 50th Anniversary set my

all time high highway mileage last fall averaging 36.36 MPG at

60-62 mph on the 2 lanes through Wisconsin to Lake Superior in the UP of Michigan. It gets 31-33 at normal interstate speeds.

This car has 55000 miles and I hope to take it to the 300000 mile club.

Link to comment
Share on other sites

I guess I'll be finding out soon enough what actual mileage I get on my 97 LeSabre. Next month I'll (hopefully) be taking it on a trip to Kingman, Arizona from Denver and fuel costs are going to be the largest cost so getting 30MPG+ would simply be great and a huge savings. Around town it already seems that I'm getting a decent margin over 20MPG which is great because I'll be taking it on a 20 mile round trip commute 5 days a week here soon. I am pretty conservative with the accelerator and mostly leave the climate control off, though. I'm quite pleased with the engine in this car since it is very smooth and quiet yet offers plenty of power when needed. It's a real shame that engines like these are being phased out.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...