shitty mpg. supercharger to blame?

n

 

Man you need to give us some rough numbers if you want any valuable feedback. At least go through half a tank and get a rough estimate of mixed city/highway mileage first...

 

It really depends on how you're driving. I installed the trd s/c on my truck, around town my mileage dropped 1-1.5 mpg, but on the highway I gained 2 mpg. But with that said. If I push the truck I can watch the gas gauge needle move

 

- Lift
- Big tires
- Supercharger

Those 3 factors will affect gas mileage. And if it has a modified exhaust add that to the list too.

RJM

 

I have a 3.4l supercharged and I get better mpg than what the original EPA estimated for my truck. Granted, I don't floor it or give it boost very often but still, something must be wrong if you're losing MPG that quickly.

I'm getting 18.5 city, 20 highway with my s/c. Maybe the ECU wasn't reflashed when your blower was installed by the previous owner? Did they install it themselves or did a dealer do it? We need a lot more info if you want a better guess.


edit: just noticed you said you had big tires. How big a lift and how big tires are we talking? Bigger than stock tires will drain your MPG real quick. Not to mention your speedometer won't be accurate which will give you an incorrect MPG calculation.

The primary reason I don't lift and get larger tires (as much as I want to for better off-road capability) is because of the effect it has on mileage. But if you are literally watching your gauge go down, then something likely isn't right. Have you actually calculated your MPG with the oversize tires taken into consideration?

 

Honestly, I was very hesitant toward buying my '04 at first because it was supercharged and I was worried that I would be spending double at the pump what I was used to spending. But I did a lot of research into how blowers work and when they're run normally (aka not run full throttle) they can actually benefit your fuel economy, because under normal operating circumstances they actually help your motor burn fuel more efficiently.

Of course, if you floor it all the time that's a different story, but that's true even if you aren't supercharged.

The only "downside" I've come to terms with is that I have to run premium fuel, but it's really only an extra 3 or 5 bucks per tank.

 

My 02 double cab 2wd Tacoma with a supercharged 2.7 averages about 15.8 mpg

 

Damn, the in town mileage on my 4.0 is 15mpg and that's with the trd s/c, aftermarket pulley, and 34" tires

 

It's hard to compare MPG (esp. when your talking superchargers) when we don't know what each other's driving habits are. I really only use boost when I'm accelerating onto the freeway and occasionally in town when I want to hear that lovable whine, but it's fair to say that I'm really conservative with it. On the other hand, if you're constantly opening up the throttle then I imagine your mileage is going to take a huge hit. If your boosting every time you accelerate up to speed then I could understand how you might feel like you're watching you gas gauge go down.

At any rate, it's hard to diagnose an issue like this online without much info....your best bet OP would be to bite the bullet and have your truck looked at, preferably by a mechanic that's familiar with performance mods or better yet, TRD specifically.

 

Your kidding, right? You have a lift with big ass heavier tires that are probably running on ridicolously heavy aftermarket wheels with a supercharger and you wonder why you have shitty mpg???

 

1st gen supercharger experience not directly comparable because it's a different system with somewhat marginal fuel delivery (hence the 7th injector kit being popular).

I get 15-16 mpg driving in town just because I rev it often, and my engine is stock except for a CAI. I think the biggest cost driver for the TRD supercharger isn't worse mileage, it's having to use 91 octane fuel.

 

My stock sport gets 17 pretty consistently.

Like others have said if you are flooring it you will see negative effects.
The lift and tires also don't help the situation.

 

I have a 2013 Baja Supercharged . Therefore, I have a lift and bigger tires also. I track my MPGs every fill up on Fuelly. I average 18.1, and that's been about 3,500 miles.

http://www.fuelly.com/driver/jedirye

EDIT: Please post some stats on your MPGs as I'm really curious.

 

hey smart guy, I wrote this post for suggestions on better fuel economy, not to figure out why my mpg was so low

 

Ok put factory wheels and stock tires back on. Tuner will do nothing. Not real hard to figure out. There are only hundreds of threads about fuel economy.

 

Stock 4.0s get around 20 mpg. Add a lift and 33s, you'll probbly be around 15 - 17. Where's a superchrger put you in addition to these? I'm actually wondering.

 

Actually the title is asking if it's the SC's fault, so technically you did.

 

You should swap your SC for my stock 4.0 stuff

 

The receipe for mpg is simple:

1) Reduce vehicle weight
2) Reduce vehicle frontal area
3) Reduce rotating mass
4) Reduce effective gearing changes from tire size increase.

What does this mean?
1) Eliminate heavy armor/accessories.
2) Reduce lift. Eliminate foreign objects in airstream like overcab light bars and roof racks.
3) Get lighter weight wheels and tires. Looks at wheel/tire pairing as a whole. Do not run E-load tires. Opt for C if off road, or P if street/forest service only. Look at changing wheel size to pair with your tire for lightest possible combo (16 vs 17).
4) Running oversized tires changes the effective gearing, causing mpg loss. Regear to get factory ratios back or reduce tire size to better match factory setup. Also check your tire pressure.

 

The hilarious thing is the "TW Way" is to do the exact opposite of all those things. MORE TIRE! MORE LIGHTBAR! MORE ARMOR!