2efnfast

iTrader: (2)

There's your problem; real men just need mechanical secondaries and no choke

But yea, I can let it sit for 6mths (w/ temps ranging from +10*C to -50*C in that time frame), prime the pump and it starts on the first few cranks (4150 850cfm holley, holley 150gph billet external electric fuel pump)

stephen4036

I use to get 11.5-13 around town in my 00 5.3 vortec, how bad could you be getting?

85LSburb

iTrader: (1)

I guess you were talking to me. I was getting 5-7 mpg in town. With 3 miles highway each way. Now i get 14 mpg and have more power.

boogiewonderland

how do you get the distributor signal worked out with coil packs i want to go with this or the msd system but what i can see you need a signal and there is only one wire for dist. position.

85LSburb

iTrader: (1)

The msd box that runs the coils has a tach output wire to run the tach. That is where the fast ECM gets the rpm signal.

boogiewonderland

wow now i feel stupid thanks i have been wrecking my brain on that.. how is your mileage improved.

85LSburb

iTrader: (1)

With the carb that was not adjusted perfict I got 7. Last time I checked I got 14 mpg with mixed driving

boogiewonderland

thats great what trans and rear gear are you running my 06 denalli only gets 17 mixed in stock trim. now i can pull the carb and order the efi system.

85LSburb

iTrader: (1)

I have a 700r4 and with the last reading it had 373gears and an open carrier. Now 410 with truetrack front and back.

boogiewonderland

Im running a 4l80 and a 3:73 the car is 3600 lbs so im getting around 12 mpg but thats with an edelbrock set up . but thats good with that gear and trans.

85LSburb

iTrader: (1)

I need a 4l80e. I can make 4 th slip at half throttle. That is pretty good with a carb.

boogiewonderland

the lock up converter is the best part especially on the highway.

85LSburb

iTrader: (1)

Mine has a lock up converter but i dont really like the short first gear. I also wish i could control how it sifts easyer. With a 4l80e all i would have to do is hook a scaner thing up to it. Just like the efi.

ZONES89RS

iTrader: (25)

That is pretty bad for overdrive. Unless that is beating it like a step child around town. With 4.30s and a t56 I was getting 17 beatin the snot out of my 6.0.

boogiewonderland

Yeah its all the stop and go driving up here thats keeps the mileage in the toilet plus i beat it like i stole it. but i really blame it on the carb running a lttle to rich as well but after some recent changes to the jetting and metering i finally got it running leaner and now i guess its about 15mpg. but i want to change efi so it can run better in the cold and get better mileage...

89gmcs15

iTrader: (7)

Talk about bad milage, th400, 6.0, 3000 total weight and im guessin I get 5 to 7 mpg.

boogiewonderland

Thats bad is it running really rich. which box are you using. whats you altitude. all affect milage i am also looking at the msd atomic system the lack of need for a return line is a good thing, but i dond like the ecu being built into the throttle body heat and vibration are not good for electronics. if your building a powerhouse than i would go carb but now if you can get an efi if you need the reliable power and economy balance.

ZONES89RS

iTrader: (25)

The atomic setup will eventually find its way to the 91 RS 4.8, sure a carb will hate the autocross events.

85LSburb

iTrader: (1)

I didn't like how you can see the fuel dripping off the Venturi. Seems like it is not atomized at all. I liked the system tell I seen that.

89gmcs15

iTrader: (7)

Im at 1550 feet, 3.73 gears, 26.66 tall tire 3400 stall with the msd 6010 box. The wideband shows 12.3 at wot but the idle smells rich. 84 and 92 main jets. Im not sure on the powervalve size. Im just gunna run it and fine tune further down the when I have time...