SOHC or DOHC (friend's)?

Both my 95 and 97 SC2's get 35 on the highway w AC. 65mph.

Well, the 95 hasn't been on a road trip in years unless you count 7 hrs rd trip to meet up with Bonestock on the day he wrecked a cylinder on his IRL coming to meet me at a restaurant. And no, I didn't think to check the mileage.
And now it belongs to my nephew.

Though I still have a badly worn key to it and told him if it is ever missing from in front of his house, call me first before reporting it stolen. Was only condition of gifting it to him.
Getting back on topic:
99 was the 1st yr of the 3rd gen of coupes and BCM freed up PCM memory so Unc you may be right. Also, they did something with the MP3 (DOHC) tranny gear ratios that may have increased mpg. It's documented. But not in this post.

 

I never got mine to better 31-33 mpg on the highway. 80mph doesnt help though lol. I averaged 27-28 between my town and highway driving if i was being nice

 

It was a dual over head Cam engine.

Father Paul was a priest from Canada, and his wife and Valerie and I did a lot of things together. His Saturn was purchased in Canada and set up to read kilometers rather than MPH. It had a lot of miles on it as he had a traveling circuit in Canada. That was about the time that the indicators that Saturn's were using oil and his had started to use quite a bit. Something else that never made a whole lot of sense. I followed him one day for quite a few miles on the Freeway, mind you state speed limit 75 mph and not the slightest indication it was burning oil based on looking for exhaust smoke out of the exhaust pipe. Thinking back it seems such a long time ago. So much of both of our worlds have changed and along with that he moved to Tennessee and we have lost track of one another. But the real time has not been a lot. It's funny the tricks your memory can play on you.

 

My 95SC2 consumed over 5 quarts of synthetic blend per 3k mi towards the end of the 1st engine.

Never a puff of smoke on the highway, never a drop of oil in the garage.
Most efficient oil burning car I've ever seen. It tended to run at a higher operating temp so I think the combustion was more complete after EGR. And the cat prob took a beating but kept doin it's thing.

Never failed inspection. CLOSE towards the very end.....but passed a tailpipe test.

I'm thinking the calibration must have been off

 

When Valerie purchased her 94 SC2 coupe the Saturn must have been successful in Phoenix. There were a number of dealers and the show rooms were busy. The dealer was in Chandler now gone of course. One thing the dealer was not happy about was the 5W20 motor oil recommendation and suggested the use of 10W30. Again, it is hot here and he had already seen engines expiring. Something that was fairly common when using a light weight oil in an environment where the temperature was triple digits 3 to 4 months of the year and hardly ever below freezing.
So that car which had about 50,000 miles on it at the time never saw 5W20 motor oil while we had it.
Fast forward another 10 years as time passed, a blue cloud following a car largely indicated a Saturn was in front of it. The lady across the street bought a SC something sedan for her daughter for her first car so I would see that one every day. Sure enough about 100,000 miles or so it would start up the road with a blue mist following it. It was traded soon afterwards. The act of checking the oil was too much to learn to do in a system with self service gas stations around and no one to check the oil any more.
We still have ours because Valerie and I are both motor heads and her coupe meant more than a car to her, it was the path to taking care of her self, the first car owned that wasn't a used up used car. It has about 100,000 miles on it now, a bit more. The odometer has quit working and I have been afraid to take the dash board apart for fear of breaking all the plastic snap pieces but I have the parts send by the fellow on the forum with the wrecking yard. Still sitting In the box that was sent in.
The thing has never used enough oil between oil changes to add any. When I started taking care of the car for her I started using 20W50 oil which I use in all my engines except something purchased almost new and then I use Mobil 1 15W50 in it.
Although my new Dodge uses variable cam shaft timing something that is dependent on oil pressure to work right and I have not figured out what the tolerances on that system is. Factory recommended is 0w15 and I am not about to use that unless I see snow on the ground.
So I am using Mobil 1 10W30 and my reading says it will get cam shaft timing error codes. I have been too busy to see if my scan tool can read the engine but it runs.
Nothing wrong with 10W30, I just wish that more consistent information was out there that talked about oil viscosity vs temperature vs engine wear.
The factory responsibility ends when the warranty runs out. People reporting engine problems are usually 2nd or 3rd owners driving what is then a high mileage car, those you see on the forum.
The original 1st owners are driving a new car, now a Kia or a Hyundai. GM quit selling Saturns made in Tennessee when they could re-badge a corporate platform designed by Opal, put together by Dawoo and imported with a bag of badges with different brand names on it thus generating Badge Engineered design and the buying public was wooed by clever advertising and good design by Kia and Hyundai. Something that they learned from GM and then GM forgot about.
Oh well, I guess I have lived lone enough to become a Grumpy Old Man who still enjoys his cars.
Before I forget, the only long term problem the Saturn had since we owned it, was running hot. It would get so hot that one point in time there were more error code lights on the dash board than I knew existed. I could keep it under control by watching the heat gauge but it bit me one day making a high speed run on the way to Flagstaff. I watched it like a hawk and got lucky nothing ever got damaged. But I eventually found out the Catalytic Converter was in a failure mode and partially blocked. It passed smog every year. When I found it out I used a generic high flow catalytic converter and overheating problems stopped.
Have a good day.
John