Rodimus_Prime

iTrader: (3)

So I've noticed alot of folks stating they get 35 and upwards highway mpg, prior to stage 2 I was getting 36 but now im only getting 30.

So beyond the obvious dialing in your MAF and VE what other changes can be made?

Theres a spot for fuel calculations for stioch which is set at 14.6 would it be safe to move that up to like 15.0 then reset the PE multipliers to match what they are supposed to be, for cruising and non full load how lean is too lean?

INFE

iTrader: (1)

your getting 30mpg and you what more lol

Josh@ottp

iTrader: (4)

I wouldn't due it. Every fuel calculation in the pcm is based off that.......most importantly the ones you dont see in hptuners.

Rodimus_Prime

iTrader: (3)

well seeing as how I lost 6mpg going to stage 2 your darn right I want more

Psykostevo

No, you don't change stoich. That is the stoich number for gasoline. You increase timing at cruising speeds.

qwikredline

mpg is as much a function of engine speed as anything else; I find that with my staqe 2 i get 26 mpg on average, city/highway, but i dont live in a big city. I just did a highway run of 500 miles today at an average 45 mph & got 31 mpg -I am happy with that. Maybe psykostevo can get better, i will have to get HP tuners and try one of his tunes to find out, but frankly, on this trip, driving a little over the limit, on 2 lane roads, and passing on torque at mid throttle and about 10 psi , I would say my little LSJ Redline is pretty darn good on fuel. In other news on this trip, this morning very early am came upon a ricer honda, and beleive it or not he went off on the on ramp looking at me in his rear view... happily he wasnt hurt. Later that morning close to my turnaround destination 250 miles in, a bike had slipped off an exit ramp...based on the number of cruisers, the locked down ramp, the broken exit sign and the state of the bike on the back of the tow truck, the rider was not as fortunate as the ricer honda....

Rodimus_Prime

iTrader: (3)

I did up the timing a little in the high octane, it made alot of progress before I got stage 2 , anything else other than timing

2K5SS/SC?

You know, I'm not really sure what process I did to end up where I'm at but in the city/partial playing around I get about 25mpg. On the highway for a long trip, I average 40-42mpg at 80mph with my 60# injectors on my current setup. All I have really played around with is my PE table and timing table after the MAF etc was dialed in. You just have to dial in that fuel at WOT and while cruising. 14.7 for regular cruising and 11.6-11.8 WOT is what works for me.

Rodimus_Prime

iTrader: (3)

damn 40-42, thats some hopes and dreams of mine right there

2K5SS/SC?

It will happen if you tune it right. My girlfriend hates the fact that my car is so ******* fast, yet it can still get better gas mileage than her 1.5L VVti Scion xB! On that trip I spoke of she was following me to the Outer Banks in NC from Charleston SC, and she had to stop and get gas while I still had a 1/4 tank left. Our tanks are about the same size too!

Psykostevo

Just don't lean out the cruise by taking fuel away. Adding timing is all you can really do. The reason the stoich is set to 14.7 is because that is the most efficient AFR for burning 87-93 octane. If you ran 100 octane you could push a 15-15.5 AFR.

Rodimus_Prime

iTrader: (3)

could one of you post a timing chart? im interested to see how much more your running

Werewolf SS

^^^^ I second that motion!

raptors_67

I have my stoich afr set to 15.2 currently, I found that anything higher lead to choppiness and hesitation at part throttling, particularly in between shifts. You will want to be sure you have closely dialed MAF tables and your VE's are spot on for throttle transitions. (I also have a pretty conservative timing map as I dial everything else in) PE also needs to be modified as it is based off of stoich and you will want to lower your PE delay, MAP delay and also TPS for entering PE. I don't have any mileage data for you as I don't daily drive the vehicle but it doesn't seem to drive any different and I can only assume mileage will increase. The cobalt/redlines are actually much simpler to lean out than my other vehicles as you can still have fuel trims enabled. I also have my silverado running at a 16.2 AFR and have had it this way for 3 months now with approximately 5000km during that period. I still have some startup and idling issues to deal with but nothing major. I will say though that my mileage has significantly increased. It is a 5.3 litre V8 in a Regular Cab Short Box and before tuning I averaged around 18MPG in the city. I have been getting around 23 to 25 MPG since modifying the AFR. (last check i consumed 30 litres in 255 Km) There have also been timing changes, shift points, etc. that couple to these values as well as LTFT and STFT disabled (they will not deviate from 14.7 if left on).

Psykostevo

A timing chart from one car to the next is irrelevant. You can only run as much timing as your car will allow. It's not hard to drag over a certain area on yoru chart and then type in a number into a field and hit the plus sign.

Area47

i won't post my timing chart, or anything else for that matter.

add 10 degree's from 0-.52 on the high octane table, copy that table and paste it to the low octane.

get rid of the VE. change the dynamic flow number to below idle. work soley off the maf. you can control part throttle stuff much easier this way

qwikredline

i dont know what all this techno stuff is about. Its easy "double any vehicles mpg! secret technology THEY want to ban! plans sources complete kits! $50.00"

Psykostevo

If it were that easy then $100 would double even that. BTW> seen those ads feel sorry for the people who try it.

qwikredline

you know what really grinds on me, is that the forum takes the ads. I know they gotta make money but these deals are 100% fraud...

Psykostevo

Well.......maybe 99.99% fraud. The other 00.01% is in the buyers head.

Rodimus_Prime

iTrader: (3)

Area - if your not going to be helpful then dont ******* post

Christ Its a ******* cobalt its not spying on North Korea, ill find my way on things without your top secret technology

throwing a blanket number over the whole table is pretty ******* stupid and if thats how your doing things, nothing you can post is of any value to me anyway

So if anyone actually wants to be helpful among those getting 40+ MPG and post a chart, it would be much appreciated, I thought thats what this forum was for, helping each other out to become more powerful and faster.

qwikredline

Chill buddy! I am often reluctant to share information so go easy I understand more than most i make my living in the car business. But something occured to me that if you dont have Option B (checking out another thread) then u for sure have local heating of the inlet charge as it simply is not possible (all my testing shows this endless data) to easily eliminate air with the stock filler tube for the h/e. Therefore unless you command otherwise through calibration, spark and fuel are affected hot inlet air, so protect motor (pull spark, add fuel) Its a total package IMHO. I have a customer with heating from the stock system it has so much air its a joke but the stage 2 install was done right, its just so hard to get the air out without the option B deal...

and i really am laughing you are funny " its a f*****g Cobalt its not spying on North Korea" lmao well said...

and i see on yet another thread rodimus prime, that you received option b today along with a new h/e .way to go!

Area47

set the stoich to 15.0, counter the pe table with the added fuel just in case. say you're commanding 1.30. set the pe to 1.40 to start with. then slowly drop it to where you want from there.

copy that same table to the low octane table. paste. yes it is that ******* simple.

keep an eye on your boost gauge. keep it below 10inhg.



something you don't know, most gas stations are on winter fuel still. this hurts gas mileage. some stations have switched already, some have not.

also. since im in a good mood for some odd reason. here is what i mean.



you can do what you want with these numbers. also, when you do these numbers, or something close to it. you are seeing positive pressure around .52-.55 so drop the table like a rock.

Rodimus_Prime

iTrader: (3)

50 degrees of timing, damn thats pretty extreme, from what im running now im about 5 degrees off it looks like

yea I would have thought most by now would have switched over from the shitty winter gas

raptors_67

Wow, I wouldn't have posted this info after you got bashed in the above post. You're a good man... lol.


The areas of 50* timing are only hit on decel as it's pretty tough to get the RPM's that high with such a small airflow at any other time.