1985 Buick LeSabre Limited Collector's Edition SE 5.0L (307) V8 from North America
Avoid the SEVERELY UNDERPOWERED 1985-1990 GM cars with the Oldsmobile 307 V8 and 7A cylinder heads
Water pump, and that's it.
This car was free, and given to me from my grandfather's estate in 1990. I am not complaining about a free car, I am complaining about poor design and engineering from GM.
As far as reliability, comfort, and style goes, this along with most other full size cars from GM, Ford and Chrysler can't be touched. The reviews on here prove that. So you can read those for a better description.
My complaint is this: In 1985, GM decided to redesign the cylinder heads on the Oldsmobile 307 V8. Instead of making the engine more powerful, they opted to make it more of a turtle and a snail. There was a ridiculous attempt to achieve a few thimble fulls more of MPG.
From 1980-1984, the 307 was actually a decent performer (for this time period), and on par with the Chevy 305. It can even be mildly modified to perform better. That all changed in 1985.
They added roller valve lifters to make it smoother. But they made the intake and exhaust ports even smaller, and redid the camshaft so the valves can't open up and lift the way they are supposed to. This engine can't rev much beyond 4000RPM, and to begin with really can't breath at all above 3000 RPM. Putting faster gears in the rear end is pointless, it simply would bring you quicker to the RPM range where the engine can't breathe and has no power.
On the engines that are affected by this, the cylinder heads are stamped "7A" or "6A" on the upper front corner. The 1980-1984 models were stamped "5A". Another way to recognize this engine is that the A.I.R. emission tubes are installed a little differently from the 1980-1984 models.
GM Models affected by this engine:
V8 equipped 1985 Buick Le Sabre/Oldsmobile Delta 88.
All 1985-1990 Full size Buick and Oldsmobile Station Wagons sold in the US, and some of the full size Chevy and Pontiac Station Wagons.
SOME (but not all) Cadillac Fleetwood Broughams from 1985-1990 (Some were lucky enough to get the Chevy 305 V8, older style 307 with the good heads, or the better performing ones from the Oldsmobile 442.)
1986-1987 V8 equipped Buick Regal.
1985-1987 Oldsmobile Cutlass Supreme (except 442, and Hurst).
On paper the HP and torque figures are nearly the same as the 1980-1984 models, but believe me, there is a HUGE, HUGE difference in performance versus the "better" 307 V8. For normal driving in city or on the highway, these things are fine. But when you need extra power (i.e. passing, merging, hill climbing) you had better plan ahead... carefully.
I have had a 1982 Oldsmobile 98 Regency (bigger, heavier car) and a 1984 Buick Estate Wagon (even bigger yet and heavier) literally blow my doors off from a dead stop. The newer 307 performs so poorly, that I've had Cutlasses, Regals, and Monte Carlos and Grand Prixs with the 2-barrel 3.8 V6 nearly beat me. A bare bones Chevy Caprice with the Chevy fuel injected 4.3 V6 was able to beat me.
It's also worse performing than most of the Pontiac 301's from 1977-1982. That's right, only the Olds 260, Pontiac 265, and Chevy 267 and the Buick carburated V6's from this era were worse performing.
It's a shame that GM (especially Buick and Olds) gave up on designing V8's in the 1980s. Buick never built another V8 again after the 1980 model year. These full size comfortable, powerful rides were the reputation Buick, Cadillac, and Oldsmobile already had for over 40 years by this time, and they destroyed that reputation with boat anchor motors like this and badge engineering.
My intent was never to drag race with this car, but the performance is laughable, even by 1980's standards. Ford/Lincoln/Mercury seems to be the only automaker that cared about preserving its full size, rear wheel drive cars until recently.
I traded this car for a 1991 Mercury Grand Marquis in 1997, and with the smaller fuel injected 302 V8, it feels like a rocket compared to that boat anchor Buick.
So just because it says "Collector's Edition" on a shiny old 1985 Buick LeSabre, or it's the last year of the rear wheel Oldsmobile Delta 88, don't assume it's anything special. The motor sure isn't...
Would you buy another car from this manufacturer? No
Review Date: 11th June, 2011
13th Jun 2011, 00:13
I think the late late 1970's (1977-1979) versions of this body style were the best performing and most reliable overall mechanically, as long as they had a 350 V8, 400, or 403 courtesy of Buick, Pontiac or Olds. Any smaller engines were far too underpowered, wore out too quickly, and turned into oil burners, especially the early Buick V6's.
The 1980-1985s versions were the best looking in my opinion and had the best fit and finish (far better style, fit and finish than the 1991-1996 Roadmaster if you ask me). The engines however were far too gutless. If they could have hung on to the 350's longer and put an overdrive transmission behind it, I'm sure the fuel mileage would be equal to the 305/307.
The Chevy 305 was okay with a 4-barrel carb, and you're right, so were the early 307's, especially the ones with the "hot cams". The 305 got a little better when it gained fuel injection in the late 1980's, but the poor Oldsmobile Slowmobile 307 got even more choked in 1985, and kept its electronic carburetor till the bitter end in 1990.