[andymac]

Hey all, I got a 1992 Seville> Any ideas on how get some more out of her? Computer chips? I know about engines, but finding parts seems difficult. anyone with some experience in this area?

 

[Ralph]

The one part I swear by and always put in my cars is a K&N filtercharger. Your part number is 33-2086, as I got this number from someone else on this site. You see, I want one for my 1991 Fleetwood FWD, but they don't make it for this. I was told your Seville and my Fleetwood have the same airbox, I hope this is true, as I will find out. My Grand Marquis could sure climb hills with that simple modification. Other than that, how about opening up the exhaust, or at least a turbo muffler, platinum spark plugs, wires, etc.

 

[andymac]

Very cool, I appreciate it. Do you know about "octane boosters". What's your take on them?

 

[Ralph]

Let me put it this way. I got my dad's Fleetwood a month ago. You know how we are supposed to run PREMIUM gas, well he thought he would save some money the last 5 or so years and run REGULAR. When I drove it a couple of years ago, it was knocking so hard I thought the pistons were going to go through the hood! You see, he is partially deaf and could not hear the knocking. Immediately following that, he used an octane booster I gave him and regularily used premium following that. The knocks went away but for the last few months before I took delivery I was concerned there would be engine damage. There isn't. At 50,000 kms, I plan to put in Bosch Platinum plugs as I have had good experience with them in other cars, performance wise and gas saving ability. I also heard from a dealer in our Province's capital that the gas in the U.S is not as high an octane or as quality as gas in Canada. I don't know if this is true or not. He said our REGULAR is like your PREMIUM. If this is true then why did my dad experience knocking or ping. I would just buy PREMIUM and not worry about boosters unless you knew you were going to race a hot rod Town Car or something. PS how much is your gas there?

 

[andymac]

I live in Indiana (midwest) and gas for 92 octane premium is about 1.70. Only two weeks ago it was like 1.90 though. Anyway... I just went to AutoZone, and all you see are these "in a bottle" engine treatment things. I dunno about all that, but thanks for your help.

 

[lux hauler]

If the manufacturer recommends 92 octane, use 92 octane. If they don't recommend premium fuel, it's not going to hurt the motor to run it but you're just spending money that you don't need to spend.
There was a discussion on here about this a while back. I'll see if I can find it.

 

[lux hauler]

here's some pretty good info on fuels.
http://www.seansa4page.com/resource/octane.html

 

[Andrew60SP]

Fastchip and Superchips makes chips for the 4.9L.

However, I do not know how effective they are.

 

[Ralph]

That's a great site, thanks Lux.

 

[jadcock]

I wouldn't recommend an octane booster because it contains a substance called MTBE I think. That stuff will coat the inside of your engine and converter with this red gunk...even after only one can of the booster. If 92 was recommended, run that. If it's not, don't run it. Either way, I'd stay away from the octane boosters.

 

[Ralph]

I know I would never use an oil treatment with TEFLON. The stuff forms chunks in an engine under high heat conditions. I read it is designed only for exterior lubrication, of some sort.

 

[Ralph]

I want to put in a new PCV valve, where the heck is it. Every other car I ever had, they were on the valve cover or the back of the intake manifold!

 

[aguthmiller]

I want to put in a new PCV valve, where the heck is it. Every other car I ever had, they were on the valve cover or the back of the intake manifold!

It is in the corner of the left valve cover on the transmission end of the engine. So for a Transverse mount engine that is the right side of the front valve cover. If it is a longitudanal (traditional) mount it is in the back of the driver's side valve cover. (I can't remember which way a 1991 Deville is, sorry). There is a plasic cover that holds the plug wires (or did anyway if the last person to tune it up took the time to put the wires in them), it also covers the PVC valve. Remove the plastic cover and see the valve.

 

[LacSeville]

see that purple tube running horizontally across the front valve cover? the one closest.... on the far right, where that black tube is, it's under that. the grommet for it is stuck in the rear right of the valve cover. your grommet will probably be gettting brittle by now, so take care when removing it... if it breaks, it's only $9 at caddy dealer though....

 

[N0DIH]

If the manufacturer recommends 92 octane, use 92 octane. If they don't recommend premium fuel, it's not going to hurt the motor to run it but you're just spending money that you don't need to spend.
There was a discussion on here about this a while back. I'll see if I can find it.

The 91 FSM has a nice little "fix", timing settings for use with 87 octane fuels for the 4.9L V8.

10 degrees for 91 or 92 Octane (I forgot which one it specifies)
6 degrees for 87.

Works for me! Save the money, and the power loss is minor.

Typical timing set, short pins A-B on ALDL, set timing to new spec and remove and drive.

Personally I have tweaked a little with timing. I am running 93 Octane on 13 degrees timing with no pinging. With 90 octane she does ping some under mild load in the 1500-2500 rpm range. Else, no pinging. I will peak it out for 93 octane just to see. Got 26.8 mpg on the way to work, combo city/highway. Can't complain there! And that trip runs me between 45-65 mph most of the trip with around 20 stops over 50.3 miles.

Can't "knock" the 4.9L! :banghead:

Tom