My edelbrock gas mileage is amazing

[Xxyion]

Originally Posted by bfrank1972

No, it's driving style & conditions. Consider these scenarios:

1) "I commute 50 miles each way on the highway, I live in rural Indiana, I'm a safety conscious driver" = you will get amazing average gas mileage, even with a supercharger. Flat, steady throttle, car gets nice an warmed up, nothing crazy

2) "I commute 50 miles each way on the highway, I live in Florida, I'm sometimes in bumper to bumper traffic" - Flat, car gets warmed up, even with some stop-n-go, your average mileage will still turn out ok

3) "I commute 25 miles each way, back roads, I live in Connecticut" = hilly, car gets warmed up, but you're constantly changing throttle and bleeding speed with your brakes, your mileage will be significantly worse than 1 or 2.

4) "I commute 6 miles each way, back roads (or not), I live in Connecticut" = this is me, I get average of 18 mpg. Without a supercharger. On 93 pump gas. For about 1/2 the trip my oil temps are < 150 deg. It's hilly. With stop signs.

That's not even taking into account the average speeds you drive, how aggressive you are on the throttle, etc. Take these scenarios with any make/model of car and you'll see these patterns (exception might be hybrids).

This is actually the best breakdown i've seen. And super true.

You could have two people who drive EXACTLY the same but based on the conditions the mileage WILL vary. How i drive in CA will give me significantly better gas mileage if i were in Nebraska.

[taiguy]

Originally Posted by bfrank1972

No, it's driving style & conditions. Consider these scenarios:

1) "I commute 50 miles each way on the highway, I live in rural Indiana, I'm a safety conscious driver" = you will get amazing average gas mileage, even with a supercharger. Flat, steady throttle, car gets nice an warmed up, nothing crazy

2) "I commute 50 miles each way on the highway, I live in Florida, I'm sometimes in bumper to bumper traffic" - Flat, car gets warmed up, even with some stop-n-go, your average mileage will still turn out ok

3) "I commute 25 miles each way, back roads, I live in Connecticut" = hilly, car gets warmed up, but you're constantly changing throttle and bleeding speed with your brakes, your mileage will be significantly worse than 1 or 2.

4) "I commute 6 miles each way, back roads (or not), I live in Connecticut" = this is me, I get average of 18 mpg. Without a supercharger. On 93 pump gas. For about 1/2 the trip my oil temps are < 150 deg. It's hilly. With stop signs.

That's not even taking into account the average speeds you drive, how aggressive you are on the throttle, etc. Take these scenarios with any make/model of car and you'll see these patterns (exception might be hybrids).

Person to person, but what about same person same car, same driving patterns - the only difference is the e-force addition.

That's what's perplexing.

[taiguy]

Originally Posted by Xxyion

I'm curious if the year the car was manufactured makes a difference.

Although i have to say i've never been above 30 mpg even when i was stock. I averaged 29. And i just checked yesterday and i'm 26.6 mpg. So for me it really didnt change much.

That's my current best guess.

[bfrank1972]

Originally Posted by taiguy

Person to person, but what about same person same car, same driving patterns - the only difference is the e-force addition.

That's what's perplexing.

Sorry, I've been lightly reading this thread but not sure of the specific discrepancies you're referring to. I saw someone who went from no SC to SC+E85 and had a big drop (expected). I saw someone who went from no SC to SC, on pump, saw a 10-15% drop (expected, especially with a PD unit).

Can you point me to the discrepancy that's perplexing you? I'd be interested to see as well.

My other post is mostly making a general statement - MPG readings are highly subjective. Even same person, same car, other variables can sometimes make it difficult to get reliable empirical results. Heck I imagine there's even a "new toy" factor - i.e. I'd bet everyone got worse gas mileage when they first bought their cars (disregarding break in effects) simply due to the fact you tend to drive your new toy harder. Over time we all probably settle down... until we put that new supercharger on. Over time I'd bet fuel economy with the supercharger will increase as the 'new toy' effect wears off

[taiguy]

Originally Posted by bfrank1972

Sorry, I've been lightly reading this thread but not sure of the specific discrepancies you're referring to. I saw someone who went from no SC to SC+E85 and had a big drop (expected). I saw someone who went from no SC to SC, on pump, saw a 10-15% drop (expected, especially with a PD unit).

Can you point me to the discrepancy that's perplexing you? I'd be interested to see as well.

My other post is mostly making a general statement - MPG readings are highly subjective. Even same person, same car, other variables can sometimes make it difficult to get reliable empirical results. Heck I imagine there's even a "new toy" factor - i.e. I'd bet everyone got worse gas mileage when they first bought their cars (disregarding break in effects) simply due to the fact you tend to drive your new toy harder. Over time we all probably settle down... until we put that new supercharger on. Over time I'd bet fuel economy with the supercharger will increase as the 'new toy' effect wears off

I went from no supercharger to supercharger with 91 gas and dropped from 29mpg combined to 19mpg combined, and I'm trying to be gentle on the accelerator. As you mentioned, others went the same route and only dropped 2-3mpg.

[bfrank1972]

Ah ok - what tune are you running? I highly doubt anything to do with the actual motor/drivetrain variations would have that much of an effect on MPG. Tune, however, very likely can. Off top of my head, have you checked your logs to see if anything is out of wack or any code being thrown? Also how is your oil usage over time (i.e. before and after supercharger).

[taiguy]

Originally Posted by bfrank1972

Ah ok - what tune are you running? I highly doubt anything to do with the actual motor/drivetrain variations would have that much of an effect on MPG. Tune, however, very likely can. Off top of my head, have you checked your logs to see if anything is out of wack or any code being thrown? Also how is your oil usage over time (i.e. before and after supercharger).

I started with a pre-CARB tune from edelbrock last May. Then I moved to the EO tune (CARB) and then EOv2, and now I'm on EOv3.

I had a check engine light come on with the EO tune for high idle. EOv2 and v3 haven't had any issues. Had high fuel trims last summer due to not hose clamping off the EVAP solenoid. Identified that leak with a smoke test and got it clamped up. Fuel trims have been normal since.

No issues with oil so far, but I'm due for an oil change in the next 400 miles.