Steve Sindt

Just bought my first mustang! It's a 1990 gt auto with 120k on it, it already has cai, bbk shorty headers, off road h pipe, said to have 3:73 gears.

I bought it from an older man who seemed to baby it. When I bought it he gave me gt40 heads (appear to be ported and polished), gt40 upper an lower intake, I believe 70 or 75mm tb, blue top injectors he said are 24lbs, and Bama tuner chip. He said once I install everything I can get that Bama tuner programmed to correct injector size, maf, and tb size.

I've looked at a lot of post and they all seem to not really answer questions about Bama tuner, is he correct will that little chip that plugs into my
Ecu really correct all that? The car does have a fuel to air ratio meter in it, it shows a 11:1 ratio.

Next question

I plan in doing a full fluid change on the car, been reading about transmission fluid changes. Some say good most say bad, I would like to run royal purple for all fluids. With 120k on it is this a bad idea to drain it all (torque converter and pan) to replace it with royal purple fluid. Or should I do just a pan and filter with motorcraft ATF?

Next question
Is under drive and smog pump delete worth it? The cars ac has already been removed including compressor an all lines.

This car is will be a weekend fun cruiser and maybe take it to a few 1/8 mile test and tunes with a few other buddies cars.

I understand there is a lot of post about this stuff, but they all seem to go off subject. Any help or input will be greatly appreciated! If any of you have any extra ideas to add please do! This is my first ever mustang and I'm so happy I got a fox body! I think I stole it for $2200 with all the parts included. I will post pictures shortly! It's clean only Missing one small piece driver front fender ground affect, other than bumper marks its nice.

mattdel

The chip on it's own won't correct it, it will need a programming by a dyno tuner. Luckily you've gotten the cost cut in half by having your own chip. 11:1 is really rich, by the way. I assume you're gathering that reading from a wideband O2 sensor? A regular one won't show correct A/F.

Tranny, go for the full flush if you want. 120k is low miles if it's been taken care of. High mileage trannys in bad shape can be "held together" with the crappy old thick fluid + metal bits, and flushing it can kill them rather quickly as the tolerances have increased. I don't forsee that happening in your case, but I've never driven it so I couldn't say for sure.

Under drive is a money scam, smog delete is a weight saver. Less front end weight means better weight distro when launching from a stop.

Steve Sindt

So from what I've read from Bama tuner, is when I change something i need it tuned, I send all info in from injector size etc.. And they program it. Do you think it would be better to find a dyno place and have them do it? Idk never have had a need for it, can i get a ball park cost?

mattdel

In my opinion it's not necessary to visit a tuning shop, or even attempt to tune these cars, until you've reached a certain plateau of horsepower. The EEC-IV computer is more than capable of tuning itself very well. Once you start with power adders such as NOX or supercharger, then you need it to prevent the engine from going bang.

The aftermarket parts market also conforms a bit to it, as you can purchase new MAF meters that are calibrated for the injector size you plan to run, eliminating the need for tuning. Some of the casings even have swappable sample tubes for later upgrades, etc.

Most tune shops tend to get about $6-800 for a full tune with a chip. I don't know much about the one you have, not even sure people outside the company can tune it.

Steve Sindt

http://s1285.photobucket.com/user/St...tml?sort=3&o=0

Ignore the old ford in a few pictures

2011scgt

if the trans fluid is nice and red and doesn't smell burnt you can change the filter and just 5 qts of fluid...if it doesn't have a trans cooler that would be your first mods..heat killes trans mission...at 120k i would just do the bolt on stuff...maybe grabbing a new block and while you enjoy the car start an engine build up...the under driving pullies are not a money scam.. i would grab a 73-76 or even an 80 mm maf since it's only 55mm stock then a TB will make some since...the exhaust on these cars are soo restrictive..if you need help just let me know

wydopnthrtl

As a Ford FEAD engineer for 6 yrs I can tell you underdrives most definitely free up TQ consumption. I'm sure mattdel has good intentions. But...

Only time I'd NOT suggest it for the typical "car guy" is if you had stock rear gears and did stop and go driving. But if its a toy car w/3.73s you'll be fine.

I'd agree with 2011scgt on the tranny. If its burnt smelling just leave it alone and start saving. If it's red or kind of a dark red you could change it yourself. Just drop the pan, let what ever can drain.. drain. New filter and top off the fluid and your good to go. (approx 3-5qts)

With that many miles I'd NOT do a full flush. Just let sleeping dogs lay.

Also on a car this old I'd suggest cleaning all the electrical grounds. Maybe even new battery cables.
My 89 w/117k looked ok. I cleaned all connections to bare metal and used some dielectric grease. Didn't make a big difference but I did notice the gauge didn't drop as low when at idle and the battery was discharging because of the underdrives.

Here is my belt routing.. (e-fan, no smog, no AC)

reldla1996

If you get a MA set up for 24# injectors, and install them (MA and injectors) together, you won't need to tune the car at all. You definitely need a larger MA, especially if you install the heads. I'm also a fan of underdrive pullies, used them on my Mustang for many years.

mattdel

Care to back that up? I'd love to see some dyno sheets of a before/after install of UD pulleys on multiple motors. We don't work on hearsay around here. Underdriving the crank might free up some static resistance from the rest of the belt system, but to say that it's increasing the efficiency of TQ production.. that's another thing entirely. We're not talking about a 50cc engine here.

wydopnthrtl

Careful now. You need to read what I said. Not what you think I said.

I was a FORD FEAD (front end accessory drive) engineer in the 90s. I've personally designed, prototyped, and tested at least 20 different FEADs. My main focus was water pumps. Only did 2 5.0L pumps. Did the Explorer and the "put a ford in your ford" for SVO. (it was actually the same pump)

As for backing it up.. well I could explain a lot of things but with your attitude I'll just give a summary. Cause I think your gonna throw rocks no matter what truth your presented with.

Engines produce torque. Engine torque is consumed by friction & http://en.wikipedia.org/wiki/AccelerationThe lower the mass of the components your spinning the less TQ is consumed when changing speed. (removing parts like the smog, fan, and AC)
The less "acceleration" the lower the TQ consumption as well. aka underdrives.
Friction is somewhat reduced by spinning the components slower. ALT, WP, PS pump, ect..

Please click on the link and read before you respond. Or else I'll consider you of no count. ;-)

If you want proof... I'll offer one case.
I saved 3ft lbs of TQ, eliminated most of the cavitation, and eliminated fatigue by redesigning the mod engine (heavy truck version) 8 blade WP impeller into a 7 blade. (volutes / strippers were 180 deg apart. 7 blades don't pass at the same time there by eliminating "oil canning" ;-) )

The engineer Tim is talking about here is me.
http://www.timskelton.com/lightning/.../navi_pump.htm

In the top pic you can see the 7 blade on the right. (on left is the 99 cobra.. I also designed). The black pump w/a long hub on it is the 8 blade version.

As for the cobra WP he states making less power.. well that simply is like saying you took 4 people off a jet and now it flies slower. Well.. that might be true but there are MUCH BIGGER forces at play than just removing a little mass. In a true apples to apples comparison less drag on a power will result in more power available for propulsion. And at $50-60 for some steel underdrives.. I think thats a pretty good bang for the buck.
It also bugs me intellectually when people say "Horse power". Cause unless a horse is running there ain't no such thing! Again.. read