RedDawnFX

Just wondering, what kind of mods help and hurt your gas mpg?
Like Turbo Help/Hurt?
Superchargers Help/hurt?
Hardtop Hurt because of added weight?
Carbon Fiber Hood helps cause of less weight?

Just those kinda things, mainly mods you would make under the hood that could help your car while giving a boost to power versus those that hurt mpg.

Nate4635

Even if a turbo helped your MPG by say 2-3....is that really the reason you'd do it?

IMO the best way to increase mileage is how you drive.
If you get a turbo/SC, you will want to use it.

ANYTHING that makes the car more efficient should help MPG if you continue to drive the car the same. The benefit of any of those mods will be so minute.

I was excited to see if my intake and tp helped....i always check my mileage and cant really tell a difference.

Light foot will be your best and free MPG mod.



HT only weighs 44 lbs - and would probably let air flow over it easier so....it may in fact help...havent done a long hwy drive with/without to tell though..

RedDawnFX

Thanks for the reply. Really I am thinking on the Turbos/SC part, do turbos help add mpg while SC subtract mpg? (Am researching options an s2k for 5 months than I want to break into a manual for a month or two while installing mods. Basically I am 16 and 1/2 and I want to research up on this stuff before getting an s2k in half a year or so to decide what the best mods will be, cause I probably won't start racing if I do until I am about 18 so I don't need power really, just want to have fun doing a few mods and such and was wondering if they would help on Mpg.

jezzder

If you go the FI route, and tune it properly, you can reduce the intake charge temperature, adjust the fuel injection map and increase the efficiency of the engine.

The problem with that though, is that you will have more power at your fingertips.

When you have power, you will use power.

Mpg will suffer accordingly.

GT_NFR

A turbo and supercharger will not help you mpg because most likely you'll want to use it. I don't know if anyone in the FI forum has reported an increase in MPG. As for the hardtop, if you do a lot of highway cruising it will def help with mpg (although small), you're reducing the Cd of your car so naturally you should get slightly better gas mileage.

tof

The turbo won't help your mileage. Don't believe those SAAB ads. Yes, the turbo "recycles" the exhaust by using its energy to spin the impeller. But you are pushing more air into the engine and the ecu will provice more fuel to go with it. Take two otherwise identical S2000s, one with a turbo and one without, and put them side by side. Accelerate at a rate slow enough to the turbo doesn't spool up. The turbo S2K will get slightly worse mileage because the geometry of the exhaust manifold is not as clean and the turbine itself decreases exhaust efficiency. Now repeat at a rate fast enough to get the turbo S2K up on boost but slow enough for the N.A. car to keep up. The turbo will still get a tad less mileage.

Same goes for superchargers assuming they have some kind of bypass system (all good kits, i.e. comptech, vortec, kraftwerk, etc) have this.
Except the losses come from system friction losses rather than degraded exhaust flow.

Now put both cars on the street with a couple of us behind the wheel. The FI mileage will SUCK because it is so much fun to take advantage of that boost. If you can resist and save the heavy throttle for "special" occasions then your mileage won't suffer much.

RedDawnFX

Thanks for all the inputs . Yeah, I never seen the Saab ads but was curious if the turbos would help much because of the added air flow to the engine. Guess I will read up on the differences between the turbos and super chargers and see if they SC are really worth the extra cost and worth working more hours of a job for if the fuel economy isn't that different .
(Cause before I thought the turbos might add on a mpg or so)

Nate4635

You do understand that a turbo system ($7k+) will not offset 2-3 mpg gained do you?


Thats if you dont fall prey to the power you gain and use it

neveronlines2k

N/A will net you the Best MPG over boost no matter what. Sorry to burst your bubble. Not too mention the increased risk of a 17yr old driving a boosted already tail happy S2000.

MPG can get even better with some weight reduction mods like adding a Ht and deleting the soft top (like the CR), buying a lighter exhaust, exhaust manifold, lighter seats, aftermarket steering wheel (risky though because it takes out Air Bag), CF Hood (as long as its actually lighter / most cheap ones weigh more than the OEM hood), CF trunk, CF doors, taking the tools/spare out of the trunk and etc.

Good luck and stay safe!