hi all i am new to this forum but i have read all the posts in the v6
group and seen all the mods and upgrades and my question is most of u have the 2.8 v6 and i was woundering is if the 2.8 parts also work on the 3.1 v6 mpfi ?


i have a 90 firebird with a 3.1 v6 mpfi all stock

 

what parts are you looking to add on to your 3.1? there are a lot of parts out there that are compatible with 2.8, 3.1, and 3.4.

 

Consider them the same motor. 99% is interchangable- exhaust, intake, fuel delivery, transmission, cams, timing chains, heads. And just about any suspension mod meant for a v8 will work (bushings, control arms, shocks) with the exception of lowering springs and most strut tower braces. All rear axle mods are the same, too (gears, posi, brakes).

V8 lowering springs expect a heavy engine, v6 isn't as heavy, so the car doesn't lower itself much- if at all. Suspension Techniques (made by BellTech) is the only v6 lowering spring available; I put them on my car.

Our v6's are too "tall" for most strut tower braces. The v8 engine lies "flatter" in the engine compartment. We only have a narrow margin between the top of our throttle bodies and the hood to fit a strut tower brace in... example; a brace that goes nearly flat across the strut towers would hit our throttle body, and the brace couldn't be bolted down.

So what's different between the 2.8 and 3.1, besides cubic inches? The way the computer measures airflow. 3.1 uses a speed density computer, 2.8 uses a mass-air design. And welcome to the forum!

 

In my understanding of the 2.8s and 3.1s, they are the same engine except for on major fact. The 3.1 is a 2.8 with a stroked crank. Look at the two and they are exact in just about every way. If you are wondering if any of the mods for the 2.8 will work on the 3.1, then yes they should all work.

What i want to know is how to get some good usefull low end power out of my 3.1 motor. I've maked the cold air intake with 3" exhaust tube that i got from autozone for $5. Some difference, now I can hear the engine sucking air when i give it gas which is cool. but I need more low end. I was thinking of polishing the exhaust and intake, but i wonder what hp increase to expect from a lopety cam. Anyone know a good cam, or any other ideas on low end power?

 

Lopey cams are horrible for low-end.. but honestly, don't expect neck-snapping torque off the line from a 2.8 or 3.1 anyway.. it just doesn't happen. These motors are worth bothering with because they're nicely balanced with their even cylinder firing and wrap out rather nicely when built to handle it..

Comp and Crane both have cams available.. check out their websites.

 

my motor won't "snap your neck" either.... it'll spin the tires too much. it will spin half way through second gear then pull of of the 'burnout' with out bogging, and i'm not talking about holding the brakes either. believe it or not, there's a lot you can do with these little motors.