Beretta.net

Worst tank to date. Im almost 100% sure it's due to the speeds I've been running. 30 mpg still isn't bad.

I still can't see 30mpg on a 100% correctly running 3100 with clocking those speeds on the highway. Your almost in open loop most of the time at that speed.

3X00-Modified wrote:I still can't see 30mpg on a 100% correctly running 3100 with clocking those speeds on the highway. Your almost in open loop most of the time at that speed.

Why would it be open loop? It shouldn't be enough TPS for PE.

Seems to be running great to me.... I don't really understand where a car this light would not be getting 25-30mpg all of the time.

woody90gtz wrote:

3X00-Modified wrote:I still can't see 30mpg on a 100% correctly running 3100 with clocking those speeds on the highway. Your almost in open loop most of the time at that speed.

Why would it be open loop? It shouldn't be enough TPS for PE.

Open loop isn't only triggered by TPS on the OBDII and OBD1.5 systems, There is another table somewhere in there that references load and RPM to trigger open loop. I've seen it happen in my car around 85+mph, I'll see the Wideband go from bouncing to 13's then 12's and then 11's sometimes depending on how long I'm holding that speed, and thats at say 30-40% throttle.

I don't have those tables mapped so I can't prove my theory, but I can say at those speeds its doing something to richen up the mixture.

theSLEEPER wrote:Seems to be running great to me.... I don't really understand where a car this light would not be getting 25-30mpg all of the time.

Because that was never the tested MPG rating of the vehicle, and to be quite honest depending on where you live, the efficiency of gasoline has dropped (addition of ethanol vs methanol in some gas) since the Beretta was even tested, as well as the regulations to come up with a MPG rating which would actually lower what the Beretta used to be listed as. Its also a 3200lb car roughly... I don't see that as overly light.

Not sure where you're getting your information Jon, but your weight guess is WAYYYYYY off.

A Beretta weighs in at right around 2800 lbs. Not 3200 lbs. Jesus, my Monte Carlo ('96) is a WHALE and it only weighs just under 3500 lbs. and is QUITE a bit larger than a Beretta, both in girth and length as well as height.

As for the fuel mileage, I managed a pretty steady 27-28mpg in the GT-T with the MPFI 3.1L motor and stock 3t40 trans. and that was city AND hwy combined. Hwy only should yield at least 30mpg. I can only assume an 3100 SFI , with it's much improved fuel dispensation system would manage at least a few mpg better. Otherwise what was the point??

As far as EPA MPG estimates , those things are NOTORIOUSLY wrong... Google it, most people that know, don't even give any weight to those bullshit estimates anymore. It's a crooked and corrupt system (bent to make manufacturers look better on how their vehicles are doing SO much better on fuel mileage) to say the least....

Depending on where you look, you'll get a variation of 5-10 lbs, but here are some links to Beretta curb weights:

http://www.carsdirect.com/1996/chevrolet/beretta/specs

http://www.kbb.com/chevrolet/beretta/19 ... spec-table

An example of why EPA MPG estimates are bogus. They claim I can only get 13/18 city/hwy respectively with my 5.4L Triton in my '05 F150 in this link:

http://www.edmunds.com/ford/f-150/2005/ ... =100447839

I ACTUALLY get about 17 in town and 21-22 on the hwy and I drive like a demon. I imagine someone with a lighter foot would do even better.

I put my 96 on a scale... I guess you could say that blows any website away. Me in it was 3175 full Z kit with fiberglass hood and about a half tank of gas. I doubt if he were to put his 96 3100 auto on a scale that it would read 2800 with him in it.

Also statement on epa ratings you contradict yourself... Why would you list them way lower than what a car can do to make you look better? Wouldn't that make it look worse?

I'll weigh it when I can. I have tons of tools in the trunk so it's probably 100 lbs over weight.

Regardless, I'll check fuel pressure, but if I get less than 28mph consistently, I'll be pissed.

Going to shoot for 450 this tank...

I'll let you know.

Well considering that over the years I averaged around 26-30, with the occasional high mpg here and there, I think getting over 28 all the time is going to be hard to do. The reason the pump pressure is a concern, is that you may end up running the engine too lean.

Jon is convinced my Z is suffering from this issue, I guess he is going to be putting the fuel rail to the test next beretta fest, he was threatening to bring a pressure tester... lol

I'm going to get a pressure tester this weekend and give it a shot.

DTMAce wrote:Jon is convinced my Z is suffering from this issue, I guess he is going to be putting the fuel rail to the test next beretta fest, he was threatening to bring a pressure tester... lol

You WILL get pressure tested next year...

My car is 2860 with a quarter tank. 5 speed z26 with full a/c.

My 240 was well under 2500. That's light. My bimmer is 3100 flat.

Sgr, not all berettas are 2800, many are over 3000 pounds...

My white car is 2650lbs empty tank, and it has the heavy ass brakes and stuff.

Thanks for posting weights guys. I'm not sure what's making your car so heavy Jon. Maybe the bigger motor and the 4t60e which IS a heavier trans?

I'm going to sound off on the fuel mileage issue as related to fuel pumps too.

Just because a few guys manage better mileage does not mean their pumps are weak. It's a POSSIBILITY , but usually a weak pump results in WORSE mileage not better. Not sure where that idea got implanted but it's complete mis-information, which is sadly, becoming a norm any more....

SuzukiGhostRider wrote:Thanks for posting weights guys. I'm not sure what's making your car so heavy Jon. Maybe the bigger motor and the 4t60e which IS a heavier trans?

I'm going to sound off on the fuel mileage issue as related to fuel pumps too.

Just because a few guys manage better mileage does not mean their pumps are weak. It's a POSSIBILITY , but usually a weak pump results in WORSE mileage not better. Not sure where that idea got implanted but it's complete mis-information, which is sadly, becoming a norm any more....

This is what I was wondering. Wouldn't low pressure cause low atomization?