Canary94GT

What performance mods can I do that will increase performance and/or gas mileage on my 1994 Mustang GT?

I'd like to increase the performance of the car, but it's a daily driver so I do not want to lower the gas mileage much more than it already is.

Or, I would look for things that would increase the gas mileage but not hurt the performance, if that is possible.

I'd prefer if they weren't too intense of mods.

I've only installed a JLT cold air intake on the car, and that hasn't done much for me.

Any ideas appreciated

AdderMk2

Coulda told you that the JLT was only going to lighten your wallet...

Do a full tune up, clean your MAF, make sure you have no vac leaks. Replace your O2 sensors if they have alot of miles on them. A better set of gears will help your mileage a little... as will understanding how to drive your car for optimum fuel efficiency. 5th gear is NOT always the right answer. Lower RPM's don't always equate to less fuel usage.

Canary94GT

Interesting.

My car seems really sluggish in 6th gear on the freeway - I can hardly accelerate, yet in lower gears it accelerates nicely.

I'm considering getting new gears. What gear ratio is stock (it's a 5 speed)?

Unfortunately the JLT intake was a few years ago, right after I had first received the car and was all excited :P

Nice car btw.

Oh, and another thing I am going to try next fill up is ethanol-free fuel to see if that has any effect on performance/gas mileage.

AdderMk2

Your car came with a 5 speed, stock. If you have a 6th gear, its because someone did a T56 swap. There are a few of them and the ratios are all different.

The factory T5 had the following gear ratios:
3.35:1, 1.99:1, 1.34:1, 1:1, 0.68:1

The rear gear ratio was either a 2.73:1, 3.08:1, or 3.27:1 (being a manual, its probably one of the first two). Changing out your gears for a 3.55 or 3.73 will likely increase you MPG, assuming your right foot behaves itself.

Canary94GT

Sorry I do not know why I said 6th gear, I meant 5th. /brainfart. The car really is completely stock minus the CAI and flowmaster cat-back, been in my family so I know nothing has been done to it.

And lol, it is hard to get that foot to behave, especially if/when it's running well

I am going to go out and buy some MAF sensor cleaner and clean it as you said, since I have never done that before (but found a guide to help). I have had slight pinging problems, and the mechanics could never really figure it out (they replaced egr valve, retarded the timing tons, to ~8 degrees currently). Hoping that will resolve the problem. I will also clean the JLT filter while I'm at it. Sigh, it's so hard to get to those in-fender CAI's.

Canary94GT

Hmm, I notice a small amount of oil is coming from the hose that leads from the oil filler cap into the intake. I've checked inside the CAI where the tube enters and there isn't a bunch of oil there, just a light misting it appears.

That tube is very loose fitting on the nipples both on the filler tube and the intake. Does it need to be tight, and should I worry about that small amount of oil? Also, I don't see a PCV valve on this tube, is that where it's supposed to be?

AdderMk2

the PCV valve in in the middle rear of the lower intake manifold. That hose doesn't need to be cranked down, but it should be snug.

Canary94GT

Yikes, just found out my rear axle is a 2.73, which explains why I only run 1450 rpm at 60mph and why it feels like I have absolutely no power at that speed. Also probably explains my semi-mediocre gas mileage.

I will definitely consider changing them, to at least 3.55