Hello! (Just a guy in a car)

[mechcd]

Hello!

I've been lurking for a while and it's finally time for a real post. There is lots of great information on here and it's really neat to see what people come up with.

I have a V6 '99 Pontiac Grand Prix GTP and a V8 '02 Crown Victoria Police Interceptor.

The Grand Prix does much better than the 'vic out of the box, I was getting 27-30 mpg without really trying and everything stock. It has now been upgraded with headers, hi-flow catalytic converter, smaller (faster) supercharger pulley, and less restriction in the air box. These were mostly for performance but my mpg started to go up into the low 30s. I picked up a used ScanGauge II to monitor knock for the supercharger, but found it had quite a few other googies like fuel trims, gallons per hour of fuel use, and engine load. These have really helped me push the bar higher on efficiency. I have since blocked the upper grille and put weatherstripping around my cheapo-poorly-fitting headlight housings, 3/4 of the sides of the hood, and added brake drag clips to my brake pads. I have recently added wheel spats, but am not sure if they have done much or anything at all.

Future and likely to occur plans include blocking the lower grille, extending the height of the front air dam, and possibly finding a way to close up the huge cup shaped openings for the fog lights. I'd like to hit 40 mpg hwy or even just catch a flicker of 40 on the trip computer.

Possible future plans include finishing up what GM started with the front under pan. They did a pretty decent job covering up the big offenders, but there are still a few areas I'd like to divert air away from. I would like to lower it just a smidgen, but lowering springs are really expensive and I'm not sure if that affects the rest of the suspension in regards to having it aligned.

The Crown Vic..... was... a salvage car that I bought for the winter and ended up thoroughly enjoying. It rides nice, handles pretty well, and has some oomph if I need it. It's a bit of a basket case but it responds exceptionally well with just a little TLC. I also have another interceptor that I got at the same auction for spare parts. That one has a huge crack in the frame and will probably be stripped for parts.

The 'vic started off with a huge weight reduction by being a police car instead of a regular model. Vinyl floor (no carpet), basic seats, no insulation anywhere, no center console, basic vinyl rear seats. I took the full size spare tire and the ammo lock box out of the trunk.

It started out with about 18 mpg highway. Every little bit of maintenance helped. Sticking brakes were replaced, wheel bearings greased, fresh juices in the trans. I turned my stock airbox into a $300 "high performance open element intake " by removing the lower half so that the entire filter is out in the open. It looks stock until you go to change the filter and there is no bottom to the box, only the clips to hold the filter in. Not really a warm air intake, but these poor 4.6 engines are so strangled at the intake and plugged up in the exhaust that opening it up made a vast improvement. I also got a junkyard alternator from a '97 that was a tad smaller and had a larger pulley, almost like an underdrive one. I'm now up to around 23-25 highway.

Future plans include somehow sealing up the monstrous body panel gaps everywhere and either making my own under body panels or finding some from a pre-98 model or Grand Marquis. I think the earlier cars had extra panels to improve airflow that were removed in later years to reduce cost.

I rigged up a switch to shut the field off on the alternator and have played around with turning it on and off under certain conditions, but don't want to do much with a standard lead acid battery.

I would like to try and hit 28 mpg without drastic measures (ps delete, electric water pump).

Whew, I think that's the most extensive summary I've ever given for either vehicle. Cheers to FE on some "big" cars!

[MobilOne]

I have a 92 CV that I bought new; so I will be eagerly watching what you do.

[BabyDiesel]

Welcome to Ecomodder mechcd!

You are doing very well with both your vehicles! Don't quote me, but you may be the 1st to touch 40 mpg with a supercharger, WHEN you do it We will help you get there!

I think 30 would be doable with the Vic.

Check out my build thread to see my attempt at covering fog light holes. Search for "Ecoscort" and it'll be towadds the middle of the tread

[Daox]

Welcome to the site.

[elhigh]

I love Crown Vics. I want one. I want it for the prowling menace, a shark cruising among a highway full of lesser fish.

I also would find it amusing to be tooling along at my usual 57mph, and everyone else on the road would be holding that speed. I normally daren't go slower for fear of getting a Peterbilt enema, but wouldn't it be nice to have them fear me for a change? Oh yes.

I'm looking forward to hearing more about your CV. I am given to understand the suspension is much heavier duty in the PI models to compensate for the added equipment and rougher use, so you may actually be starting from a higher curb weight than civilian models.

Is that a belt driven fan under the hood? With lots of expected idling and super heavy alternator loads, it may have been. That might be some low hanging fruit too.

[mechcd]

Thanks for the encouragement!

I really want to work on them both a little more, but it's a tough balance to keep them all running, working full time, and trying to stay sane.

It seems like alternator amp draw makes a much larger impact than I thought on both cars. The lights and hvac blower just soak up the power and I can watch the mpg go down after I turn them on. Luckily the Grand Prix has the digital climate control option, so it actually has a PWM controller for the blower instead of a big stupid resistor. I might add some fixed resistors to the blower switch on the 'Vic use a cheap variable PWM or buck controller behind the scenes to bypass the inefficient fan resistor. I kind of prefer the preset 1-5 settings and wouldn't have to hack up the dash to mount a potentiometer for the controller.

Putting LED bulbs on the rear of the Grand Prix reduced the rear lighting load from around 25 W to under 8 W. It's an even larger reduction at stop lights with the brakes or turn signals on. The voltage and brightness no longer sag in tune with the turn signals and brake lights at intersections either. I had always thought that something like 25 W wouldn't even make the 140 amp alt blink an eye, but it doesn't seem to be the case. A lot of the street performance guys run higher amp alternators for some reason and it seems like smaller might actually be better as long as you have enough juice to run the ignition.

Now if I could just keep my coroplast wheel spats from falling off.......

I have some experience with making fiberglass stuff for multiple cast parts or thermoforming molds, but not one-off stuff. It shouldn't be too hard to make custom panels and what not, but I don't know where to start or what to make. I no longer have access to a thermoforming table, which would be far easier. Just carve up some foam or wood, slap it on the vac table, heat the plastic sheet (cut up 2L pop bottles work well!) and turn on the vacuum.

BabyDiesel: I think the stock ECM engages the Boost Bypass Valve at cruise so the supercharger doesn't build any pressure. I tired just taking the belt off and it made the car a lot less responsive and required a lot more throttle to get on the highway and maintain speed. Some sort of balance seems to be the best. Whatever GM came up with actually works LOL

[dirtydave]

I also love the crown vics cant wait to see what you can do

[mechcd]

Bad news on the cruiser

It's missing just about every piece of plastic underneath except the tiny air deflector that runs across the bottom of the radiator. I thought it looked like there was supposed to be something down there. I had assumed it was a "decontent" on Ford's end of things. I'm going to check the junkyard, but I'm not holding my breath. These are pieces that usually people either don't know/care about or throw away to make maintenance easier.

I think it's within my abilities to smooth out the area from the bumper to just in front of the sway bar. I would like to do something with the grille. Too bad all of my Coroplast is white. So is my aluminum trim coil. Maybe it's time for cardboard and cut up trash bags?

I will start a build thread once I actually get started.

[mechcd]

I forgot to mention that the 'Vic has a two speed electric fan... with a giant resistor to get low speed

Rain gutter side skirts look pretty easy to do. It would be a quite a bit of time lost if they didn't improve anything though. I'm still hesitant to drill holes even though it's a beater.

I was poking around under the front end this morning before it got too hot outside. The air deflector off an '03 that looks like it should should fit. I also got some pieces from a '98-'02 that go near the wheel wells.

It looks like it would be easy to bridge the gap from the bottom of the bumper to just under the radiator. The '03 air deflector would continue behind the radiator. Some u-clip-nuts should work well with the big roll of aluminum trim/flashing I have.

[Baltothewolf]

That's odd, my friend has a '91 vic (non ex police) and he gets 28-31 on the highway -shrugs-.