premium vs. regular pump gas
 

When I bought the SSEi a couple weeks ago, I was getting mized signals from various owners of SSEi's that I was test driving. Most were using just regular gas (87 or 89 octane) vs. the stated premium (91 or better octane). No one mentioned adverse effects to the powerplant except some people did bring up the possibility that they got better mileage with premium.

What's the deal here, since I'm sceptical to beleive anything someone trying to sell a car to me will say (they'll say anything to sell, obviously), I figure I'm better off asking current owners. I've been using strictly premium since I bought the car but since my mileage isn't all that impressive (could be other problems, but thought I'd tackle this idea first) I just want some other opinions.

Cheers!
Bryan

an SSEi will in fact run on lower octane BUT it will not run as efficiently or strongly...due to the lower octane rating you will be having lots and lots of KR (knock retard) in which the engine sinces knocking from premature detonation(from the lower octane) and to compensate it retards the timing, making the engine run less efficiently and not as strongly...there are members that know more and can explain better. but this will have to do for now.

you may hear some "pinging", not have as much power, and lose some gas milage trying to make up for the lost power of the octane. I cant remember what the "pinging" is, but if i remember right, it wont hurt your car. (I have an SE, so i dont know this off the top of my head) Good luck. 8)

Don't run regular. The cons outweigh the pros.

you will get worse milage with the regular that you will with the premium...well worth the extra cost

Pinging can indeed cause serious damage to your engine, if severe enough. Besides what you can hear, there are ultrasonic frequencies involved that you can not hear. The knock sensors should save you from damage, however. Use the premium gas, it's "cheap insurance" and will let your engine run as it is designed.

Since no one is really summing it up...here's my version.

Most of these cars come with an owners manual that says you can run 87 and 89 w/o problems, but don't expect the power and effieciency.

The engine has a sensor, the knock sensor that detects the knock or pings as stated above and the computer then retards the timing (affecting power and effiecency) to keep that knocking and pinging from occuring. This is if all systems are 100%, if that sensor fails, the repercussions could be bad.

Then from another honest opinion..I like the feel of the super in the throttle. So much I can't keep my foot off it. :oops:

If I recall Correctly the 92-95 supercahrged 3800 (Series 1) states in the owners manual or on the fuel filler door "USE PREMIUM UNLEADED ONLY".
The 1996+ Supercharged 3800 (Series II and Series III) says you can use regular unleaded, but if pinging or knocking occurs (detonation -pre-ignition of the gas before that cylinder fires, which means the cylinder temps are way too high), you should switch to premium unleaded immediately.

I'd say if you are really close to sea level you might get away with 87 octane in the 96+ and maybe 89/90 in the 92-95, but any elevation over 500' above sea level I'd highly recommend you use premium, especially in the mountians where' you might see 2000' + above sea level very often.

Another key to avoiding the pinging and knocking is to give your car a full tuneup, consisting of new plugs, wires, fuel filter, pcv valve, air filter, cleaning the TB, and if you feel like spending an extra $10 a 180* thermostat (not recommended for the colder regions of North America where temps dip far below 0*F (say -10*F or colder).

i have a series II and on my fuel door it says "USE PREMIUM UNLEADED ONLY".

Interesting. Did you check the owners manual yet?