02 Pontiac Sunfire Build.

[backpacker3]

So I was reviewing some of the info from my trip and here was the good news, the total distance of the trip required me to get slightly more than 30 mpg to make it to my destination with one tank. Which I did. I got 33 mpg on the way down and I also made it back on one tank as well even though it was a bit of a longer drive back because of traffic and having to drop a friend off which added a bit more distance and an extra passenger and we were using the AC almost the whole way home.

All of that has me pretty confident in what kind of mileage my car has to offer so here are some things I'd like to get done soon.

Instrumentation, I've been going back and forth on this because I'm working on a OBDuino project but I've decided that in the meantime I need something to work with to get some baselines on a few different things.

Gap sealing, there are some pretty big ones I can get rid of around the headlights are the biggest ones but also the front fog lights and a few other spots.

Rear belly pan, I've got some ideas for this and it should be pretty easy due to the design of the spare tire space in the trunk. I will need a new muffler for this but I've found a smaller replacement that actually sounds good and isn't that loud at low rpms. The muffler will also let me take the heat shielding off for the current exhaust which will be a little bit of weight reduction too.

Replacing the missing wheel liner, I broke that when I changed the serpentine belt and all the junkyards around here want me to buy a whole fender to fix it. I might have sourced one so I'll see if it works out.

Cleaning, I want to get my engine bay cleaned and get the rust off my brakes as well as a few other things like that.

Overall I think those things could get me to 45 mpg which is close to my 50 mpg goal. I'm just going to keep picking away at them and see what I get though.

[Daox]

I'm looking forward to seeing what your mods do for you.

[backpacker3]

Me too! The bad news was that I've found a few things that said the scangauge doesn't work as well in j body's which is a bummer, I'm trying to find some more info on what the problem is but supposedly even some of the basic functions don't work which is a bit worrisome. The scangauge e I wanted fell through so I'm looking around a bit more but I'm thinking I might just get an ultragauge.

[Daox]

I haven't had any issues with the SGII on my Sunfire. What issues did you read about?

[backpacker3]

On the j body site they were saying that there were a lot of basic functions that wouldn't display and that there were some accuracy issues. The only thing I'm not sure of is if it's the SG 1 or SG 2 that was the problem the threads are less than a year old that I found so I just want to check before I buy one. It was the newer ones that were having the problem like the 02 years and up but it might be fixed by now

[backpacker3]

I'm just saving this link here http://ecomodder.com/forum/showthrea...ods-20741.html I think the contents might be useful later on.

[backpacker3]

I fueled up today and got 30.81 mpg which I was happy with considering that was the tank from my vacation that had me and 2 other passengers in the car with AC on plus added weight from all the gear we had in there going 70mph for the majority of the way.

Also I had a ~20 mile trip to the harbor freight store and back all city driving at 40-50 mph plenty of stoplights too. So I was monitoring my gauges and this was what I found.

Acceleration under 2500rpm is painfully slow if I am really careful I can get decent acceleration at 2000rpm and if I really take my time I can keep it to 1850rpm but the car really likes it at 2500rpm.

At 40mph I can get into 4th gear and accelerate to 50 at about 1650rpm and hold constant speed anywhere from 40-55 mph in 4th at just under 1500rpm.

In 3rd gear at 40mph I'm at about 1800rpm.

Gliding puts me at about 1000 rpm avg and as low as 800 rpm but I don't know if it's in dfco mode or not.

So all that leads me to believe that I'm going to have to get my RPMs lower if I'm going to get 30mpg city. And that I could probably get 45 mpg at 55 mph in 4th gear maybe even as high as 48mpg.

Thoughts and suggestions are welcome.

[backpacker3]

My fender has paint again! I'll get some pics up later after I have the clear coat finished. It looks so much better now even before the paint is fully dried.

[dirtydave]

What are you doing when you slow down? Staying in gear? Neutral? Engine off neutral?

And don't let passengers or other drivers decide how fast you go!

[backpacker3]

Originally Posted by dirtydave

What are you doing when you slow down? Staying in gear? Neutral? Engine off neutral?

And don't let passengers or other drivers decide how fast you go!

Slowing down/gliding I just stay in gear it's an auto so I don't have the benefit of a manual trans. Switching to neutral doesn't make enough of a difference to make it worthwhile and I'm still not sure about EOC in an automatic just yet .

I'm not at all worried about passengers/other drivers so no problems there
I always go the speed limit since I'm live in an area where it's mostly 2 lane 55 mph speed limit roads and everybody else is going 65 mph+ so I'm used to the dirty looks, but the acceleration is where I'm still having trouble. Because the engine has the majority of the power band at 2400-3500 rpm acceleration below 2400 rpm is painfully slow like I said in my previous post, and to accelerate around 2000 rpm which is where I'd like to be able to stay at or below is really really really sloooooooowwwww. I mean, were talking 0-20 in over 10 seconds slow, like full on obstruction of traffic ticket even seniors on their Sunday drive give you dirty looks slow. This is a very fitting illustration of acceleration at low rpm so needless to say I'm looking into seeing if I can get a little more torque at the lower rpm range so well see what can be done.