best mileage test/poll...

[unruhjonny]

car: 1991 Grand Am
engine: stock LGO block with unported 086, ported exhaust manifold, 224/430 cams (intake advanced four degrees)
transmission: 3.94:1 (non-w41)
exhaust: stock headpipe, 2.5" pipe to Flowmaster crossflow muffler

So I'm doing another road trip, and figured I'd try to see which chip would result in the best mileage.
This will not be a totally precise test, as the terrain will greatly differ, and I'll use my odometer between fills as a way of recording this...

What do you think will net the best milieage with my car?

[jeffe_de_walla]

haha I'm first poll :D

[c0mbatphil]

mileage. pssh. :D

[unruhjonny]

mileage. pssh. :D

look here - then my mileage comment should make complete sense!;

A Community for the GM Quad 4 and Twin Cam Engines - View Single Post - required ammount of vacuum? (http://www.quad4forums.com/forums/showpost.php?p=177527&postcount=17)

[unruhjonny]

btw - Phil, I presume it was you who voted for the Skoda! ;)
(I'm glad some one picked it!!)

[c0mbatphil]

skoda FTW!!!

[unruhjonny]

Why - Does it make you think of this? ;)

YouTube - Romanian Street Racing (!?!?!?!) A MUST SEE :)

My Croatian co-worker didn't see the humor in that video BTW :wtf:

[c0mbatphil]

bahahhaaa. i wonder why?

[bear8ruf]

I say the Rocketparts chip. The actual fuel maps shouldn't matter one bit, as you will be in closed loop while you are cruising along. The best mileage should come from the chip with the most aggressive ignition curve that doesn't result in detonation. I'm guessing that will be the Rocketparts chip, although you may need to run high octane to take advantage of it (if you are getting spark knock and auto-retard.)

[unruhjonny]

I only run premium if I have any say in it - I get worse mileage if I have to put anything else in.

[90BerettaGTZ]

wont matter.

[Fbod383]

what the truck is an HG2!!?

[unruhjonny]

HG2 is the nickname used for Ron's custom 224 duration / .430 lift cams.

I think the name was taken from cams that were once offered through MP(?)

Wow... for you to have to ask that question - you really have been gone a long time!!

[weba]

I would not even try Rocketparts chip without keeping eye on ALDL readers knock counter & retard.. and wideband O2 would be good too.. Correct me if i'm wrong but that chip was programmed for early 90's racing fuel?

[unruhjonny]

my results should be up tonight.

I will readily acknowledge that I didn't get the best mileage possible, becasue from experience to get optimal mileage, you need to keep the engine below 3k rpm, and I was most definitely above it - especially if I was in "test" sections of the interstate that had a posted speed limit of 80mph (I seldomly sat right at the limit; If I wasn't pushing my luck, I normally was roughly 5-8 mph over the posted limit)

Oregon is the slowest state btw - in additon to it technically being illegal to pump your own gas in OR.* :down:, they also appear to have the lowest speed limit - many sections had 60mph limit, where as the average for every other state was 70-75mph...
* = probably the stupidest law I have ever come across btw!

[bear8ruf]

probably the stupidest law I have ever come across btw!

I get a little paranoid when I travel to unfamiliar states. I have been detained for breaking laws that I didn't know about in places like Nebraska.

[unruhjonny]

care to tell us about it?

the gas jokey law is bogus though...
I have (when driving the Firebird) had gas jokeys allow me to pump my own gas* though...
so I know it's partly a unionized deal that creates otherwise pointless jobs ect...

* - both my Firebirds have fuel filler necks for leaded gas - and I have had idiots get gas nozels wedged in them before... so I normally am poite, and insists on doing it; after explaining why, I have not had a single person not let me...

[unruhjonny]

by the time I was in Portland I saw the writing on the wall...

All together I traveled over 3500 miles round trip.

Although unintentional, it should be noted that this trip was slanted to give the ASDH chip an advantage because a good chunk of the leg in which I used this chip in fact had the lowest speed limit (which equates to lower revs).

Here's average milieage between fills for each chip type;
ASDH = 28.078mpg
AXRM = 29.159mpg
Rocketparts = 27.989mpg

Peak mileage obsevered between fills with each chip type;
ASDH = 29.798mpg
AXRM = 33.630mpg
Rocketparts = 30.789mpg

The all around winner, AXRM.

We had seven serious votes, only one of which guessed correctly!

Hopefully this helps out someone when planning a road trip ~ saving money is always a good thing!

:up:

[racin17]

Hm, so what RPM range were you running in? I'm a little curious to look at ignition timing values in those RPM ranges, and compare chips.

Jeff

[unruhjonny]

I believe that at 75mph, I'm just over 3k rpm... but off hand I might be mistaken... maybe it was 70mph that put me in at just over 3k rpm...

if you really want to figure out rpm's, I was running a non-W41 3.94 transmission... :shrug:

EDIT:

BTW, how long have you been adding the 'fix' to your custom AXRM chips?

I have one EEprom that I can burn a 100% stock AXRM bin to, but since I sold my legit AXRM, I've been using the one you set me up with a couple years back...

[zppr17j]

best results I have had are with the RP chip. but really I seemed to get basically the same mpg no matter what I do with my car. barring putting a 3.61fdr back in, it gets 29mpg at 65-70mph. FYI stock, with 3.61, it got 29-31max mpg

I have the scx tranny in, so I turn a few more rpm, I have basically stock engine at this time. I dont know how you guys get 33mpg, I fill the tank, reset the trip. then on a long trip I will add the gallons up over say 3 tanks full. my car is also extreemly touchy to humidity. if it rains or is humind or just coll-cold out my mpg tanks. my car gets the best mpg at 55mph in 90f with low humidity. then it will get in the range of 31mpg. I think the best I have ever seen out of it is like 31.5mpg. 33mpg? ha no. only car I ever had that would do that good was a 84 honda accord, it would get 33 on avg, and up to 42mpg if it was really hot and dry. I did have a 90 honda it got 30-31 mpg.

[bear8ruf]

So my 2500 rpm at 75 mph is what gets me up to 37mpg?? (If I drive nice.)

[racin17]

BTW, how long have you been adding the 'fix' to your custom AXRM chips?
Hey Unruh, sorry, kept getting sidetracked... I've been putting the "cold hesitation fixes" into chips starting in (mid-late) 2008. Your chip was made in 2007. I probably had not yet known that I could apply those fixes to the W41 chip at that time. (I think I started out only giving them to people who wanted or asked for them, but I've decided that I will just make them automatic from now on and include them in any chip that I make (which applies only to about '91 and before anyway, since GM had that fix on the production chips after that).)

I haven't looked yet at the ignition timing at around 3000 RPM (with light load). The only tables I have printed out are the Power Enrichment tables, but it's probably not in PE mode while cruising along. I'll have to open the .bin files to look at them.

Jeff

[unruhjonny]

I would not even try Rocketparts chip without keeping eye on ALDL readers knock counter & retard.. and wideband O2 would be good too.. Correct me if i'm wrong but that chip was programmed for early 90's racing fuel?

I remembered this post, but untill now haven't really had any time to dedicate to it - I'm looking at the knock retard stuff right now...

LGO vs RP;

they're both there, I'm seeing that the RP chips doesn't retard it as much in non-WOT, while it's exactly the same for WOT - and many of these types of values seem to be the same between LGO & Rocketparts...

the most noticable difference between any LGO & RP chip seems to be how quickly advance comes on, and how rich it runs...

I'd really like to be able to kick up the shift light point when warm, but can't seem to exceed 6375rpm - I'm not sure if it's a limitation of the program I'm playing with, or something else!?
:shrug:

[bear8ruf]

Mods?? I think a quick banning is in order!