First mod to a stock '89 Mustang GT

Subframes or a high stall converter and shift kit.

Subframes are always a given, next for an auto would be 4.10's.

a trailer hitch to hang one of those rubber nutsacks



































































































wut?

+1 for the subframe connectors or any chassis upgrade for that matter and +10 to the hitch/rubber sacks

I started with a cold air kit, Headers and a full 2 1/2 pipes all the way to some flowmasters. Based on what state you live in get rid of the catalytic converters. One of the most noticable upgrades I've done is a strut tower brace, subframes connectors, they even make a brace for rear shocks if you have a Notch back of hatch. Foxs are known for the flex up front and strut tower brace alone improved the way car handles cornering immensely. Warning..... One you play with the MOD God you wont stop

87-t-top-gt said:

+1 for the subframe connectors or any chassis upgrade for that matter and +10 to the hitch/rubber sacks

Click to expand...

lmao!

Welcome to stangnet. Congrats on the ride. I will offer my two cents as well. I would say the biggest seat of the pants mod would be gears. Many recommend 4.10s for autos and 373 or 355 for 5 spds. Subframes are also a good mod as well as upgrading to better shocks/struts and lowering springs. These were effect your MPG as the gears do.

Just a heads up. This is the tech section and this question is probably better suited for the talk section and you would probably get more responses there too.

Supercharger. Go big or go home.












Byahhhhh!!!!!

A nice exhaust system and subframe connectors

Subframe connectors and gears for sure

SFCs first... while this will substantially tighten up the chassis and improve handling, the real reason you're doing this is to prevent yourself from allowing the frame/body to further warp.

Afterwards, since you're interested in gas mileage and increasing performance, why not a T5 or T56 swap? This will improve 1/4 mile ETs by 1/2 second or so, which is huge for any single modification at your power level, AND it will improve economy at the same time. Not to mention, the manual trannies will last longer than stocker autos. It's a lot to take on, but it seems to fit the parameters of your question.

Alternatively, if you're just looking for a power boost and making your car cooler, then I'd say exhaust is a pretty good place to start... a set of 1 5/8" long-tube headers with corresponding H or X pipe, and the 2.5"+ muffler and tail pipe of your choice should not only net you a solid 15-20 hp, but will also make the car sound badass, too!

You can still get decent mileage (low 20s or so) with 3.73s, but since you don't want to hurt mileage, I'd stay away from them.