Im am going to be buying and LS1 hopefully in the next few weeks and i am going to be driving it 100 miles a day to/from school in the fall. I was just wondering if certain mods increase or decrease fuel milage any noticable amount?

 

A lot of them will decrease your mileage some, but not a whole lot until you get into the bigger mods.

I'd say stick to bolt-ons (intake, exhaust, suspension, etc) and see where that takes you. Then give a try to some longtube headers, just make sure you get your car tuned right after to get the most power and not lose much if any mileage.

If you get an M6, go with a set of gears, although since mileage is a concern you may not want to get 4.10s, might want to go with 3.73s. If you get an A4, get a mild converter (I'd say no more than 3200 stall to preserve mileage) and maybe some 3.42 gears.

After that, you could go with a mild cam, as those won't decrease your mileage. More aggressive heads/cam setups will cost you more mileage.

Then there's always nitrous... doesn't cost you any mileage at all when you're not using it. But then that extra boost of 100+ hp is there whenever you need it.

 

You could go with forced induction, which wouldn't affect your gas mileage as long as you kept your foot off the pedal. There are guys with full boltons & heads/cams package that still easily pull 25+ mpg on the highway. Since you said you would be driving 100 miles a day (ouch), you shouldn't be worried at all.

 

When I put a underdrive crank pulley on my 3.1.I actully noticed like 25-30 more miles per tank.

 

watch out for the cam though,someone people,even with small cams lose quite a bit of gas mileage,and on rare occasions a few actually have gotten better gas mileage.If you have an M6 you dont car because on the highway your in 6th gear doing 80 and your tach says 1900rpms or so.so its great!

 

I know ive seen a lot of tihngs on like SLP's website that that say improve fuel economy, is this true?

 

it all depends on the cam.currently i have a LPE GT2-3 cam,considered a babe cam,and my gas mileage got worse,but ive seen a few people with like a 222/222 get better gas mileage.you dont really get a cam to improve mileage,so be prepared for the worst and if it ends up not being that bad then youre happy.

 

S/C's won't affect your mileage at all until you go WOT. Turbo's might have more of an effect, since they start working earlier in your powerband. I've heard on SRT-4 forums of people getting 15mpg stock! I'm not sure if they go WOT everywhere, or if those turbos just suck that much, but it was what turned me off of the car the most.

a 2.2L 4 banger and it can't clear 20mpg?

 

you have it totally backwards.supercharger kick in straight from idle,turbos have to spool and build boost so as long as youre under boost its like your stock,with a turbo.thats 1 reason i went turbo.

 

no they don't. most superchargers don't kick in until about 5k.

 

100 mile round trip? Why not buy a cheap beater to make the trip, and save your LS1 car for after classes & the weekend?

 

ill bet you a $1000 thats not true.youve got it backwards.

 

redline4816 pleaes dont listen to crabhartz28,and no offense to him,but he has it totally backwards.Superchargers are belt driven using the crankshaft so they have instant on demand power.Turbos use exhaust gases to spool which means as you go through the power band the turbo builds boost,which is NOT instantaneous.do research because you dont want to be misled.

 

dont mean to start anything with all this power adder talk, i thnk that a turbo or supercharger is out of the question anyway because of price.

And i dont want to buy a beater for the trip, dont want to pay insurance on two cars, and i want something that makes my trip everday enjoyable

 

Not entirely...There's a difference between engine efficiency and engine fuel economy. Usually if you add more power N/A then you're going to lose gas milage because you're making you're engine use more fuel to get that power. Like if you get a big lope cam, you're going to lose gas milage whether your foot is in it or not. However, the bigger the engine size the more efficient it becomes in terms of fuel usage per energy made. I don't have a link, but that infamous big I6 or I8 engine that was made for a boat or whatever where people were walking inside of it, that was like 50% efficient, where-as regular passenger vehicle engines are only like 20% efficent on average. The problem is that it uses WAY more fuel to make those big engines turn that much energy.