I'm new hear to the forums. Been reading them a while and decided to turn to them to get some insight. I have a 97 sc1. I am planning on building this car for show level, not racer. The idea is to look great, with awesome Mpg still as well. So far the only upgrades I plan on doing is cold air, headers, exhaust, engine and tranny rebuild, amongst a few others. My question is basically anything you would recommend to help out my Mpg's, I know the cold air will not, but I love the sound. I'm very mechanically inclined. Sorry if I posted in the wrong forum.

 

Welcome to the forum. We have a church convention every summer in Valdosta. The CAI may actually cost your some mileage if you like putting your foot in it and hearing the sound it makes. Stay with the stock air filter and you'll probably be better off. Other than slow take offs and driving under the posted speed limits, I don't know any way to improve your gas mileage. Good luck with the project.

 

My main goal is to atleast run 28-32 highway. The cold air as well as 1/4" bigger exhaust will take down the mileage, but I need something more than an almost factory sound, something agressive. That's a long drive I've made a few times myself, lol.

 

hell if you leave it untouched you should exceed that mpg provided you are not a total leadfoot.

I have two twin cam (sc2) 5 speeds that get 35mpg highway on pretty much flat roads since they were new in 95 and 97. Tou have an SC1 which I'm sure is rated higher (don't know the specs offhand. Bone Stock

 

When I rebuild the motor and tranny I do plan on keeping all internals stock, aside from drilling oil drain holes in the pistons, or just buying aftermarket ones pre-drilled, considering I burn 1 quart to about 700 miles. I'm running in the low 30's right now. All stock. Any suggestions on getting a little higher? I replaced the ects, tune-up, cleaned coil packs. Next thing is fuel filter I suppose.

 

Keep your foot out of it and drive 5mph under the posted speed limits. That will pick up your mileage.

 

Show car, does that mean big audio? Do you have an AT or 5 speed?

 

It's a 5 speed. And it will definately have a nice system in it as well. Any brand
recommendations?

 

No brand recommendations, to me they are all about the same so I go by price vs specs. Don't get hooked on watts also, you need to look at the THD (total harmonic distortion). Any brand that won't give you that spec is automatically suspect to me. On speakers, I look for frequency response +0, -3dB. Frequency response without the +/- dB means they are looking at +/- 20 dB or greater.

If you go beyond a total of 500 watts, including the sub, you will need to get a high output alternator. A 245 amp police alternator would be needed to power a 1000 watt system (500w sub, 125w/ch, RMS). You can get one for around $800 but it will cut into your gas mileage quite a bit.

You can use a 89 dB/watt spl (sound pressure level) @1 meter as a normal spec for most quality 6.75 coaxial or component speakers. a typical head unit will supply 20 to 25 watts RMS per channel. Since the inside of your car will be within 1 meter of at least two speakers, you will be getting about 108 dB inside your car, not counting the sub.

It is not uncommon for 10" speakers used in subs reach upwards of 110 dB/watt spl @ 1 meter. A 100 watt sub amp would generate about 130 dB in the trunk. If the seats are still up, that will still be 110 dB inside the car. That will give you about a total of about 112 dB total volume inside your car, which is a bit loud. 105 dB is concert level.

That should be more than enough for your personal listening pleasure, in fact enough to cause hearing loss, but at a car show where you open the doors and trunk and try to fill an auditorium, then you will need the external power amps to hit the 130 dB levels. 900 to 1000 watts total RMS should do for that.

 

Be sure you soundproof the hell out of the car as you go. Remember all but the hood trunk lid and roof are PLASTIC. Internal door panels -- plastic. Rear side internal panels -- plastic. Soundproofing in the doors right now is a piece of Styrofoam. You'll see when you pull the door panels to do the speakers.

Dash-- many pieces of plastic mounted to many pieces of plastic.

Remember this was a $13K car back in the day so fit n finish was not always the best.

Have I done an audio system on my s cars? No. Do they rattle like hell without one?

Yep.