Just curious

[85 22rYota]

I was just wandering for example if you where to take a new 4.6 mustang motor and bore and stroke it and keep the fuel injection what if any things would you have to do with the computer. Im just wandering trying to learn more about motors

[351wStang]

Well by boring and stroking the motor you are increasing the cubic inch. Therefore you are going to need more air/fuel in order for the motor to run efficiently. So you would need to get a tuner and add fuel and adjust the timing as needed to keep the motor happy. Or you could go to a dyno and have a custom chip burned for your application.
But, to be honest with you to bore/stroke a 4.6 and then leave everything else alone is a waste of money. The 4.6 will make plenty of power with the stock 281ci.
Personally if I had a modular car it would be a 99+ GT and I'd just get exhaust, gears, air filter, and a 75hp shot or so of nitrous.

Let me know if you have any more questions. I'm not too good with the computer side of things, hence why I run a carb. But I'll try to answere your questions anyway lol.

[85 22rYota]

Thanks i was just wandering cause when it comes to computer i am more lost than without them and in my 86 gt i want to keep fuel injected but i am going to put a lot of after market stuff on it will i have to do anything to the computer or does it even have one that you can up grade

[351wStang]

I'm not positive, but you may have to swap to the A9L computer if yours doesnt have it already.

[85 22rYota]

How do you remember all this stuff lol you have an answer to like every thing which is good cause so far you have helped out a lot so where would i get a A9L computer are they in later 5.0

[351wStang]

As far as I know the A9L computers are in '87-'93 5.0 mustangs, but they may just be in the '89-'93 cars since '89 was the first year of the MAF sensor on these cars. Like I said I'm not too good with the computer side of things lol. But you may try the classified at the corral, there may be one for sale over there. Or post a wanted add, some guys may have them laying in the garage collecting dust if they have converted to a stand alone fuel and ignition system ect.

[GTStang]

The majority of tuning options for your 86GT are going to be MAF based. So that means your going to need to switch to a MAF computer like an A9L and do a MAF conversion.

Your speed density tuning options are AEM plug and play, or then just any other stand-alones replacements, FAST, DFI. Megasquirt is a nice cheap powerful option but requires some serious knowledge on your part.

[351wStang]

So the A9L wasnt used until '89 when the MAF system was first used on the 5.0? I knew he could keep it sd but then he would be dependant on a chip to do its job and keep the car running right. Whereas with a FAST, MS, BS3, whatever you can get a precise tune for every throttle position and rpm between idle and wot correct?

[GTStang]

Originally Posted by 351wStang

So the A9L wasnt used until '89 when the MAF system was first used on the 5.0? I knew he could keep it sd but then he would be dependant on a chip to do its job and keep the car running right. Whereas with a FAST, MS, BS3, whatever you can get a precise tune for every throttle position and rpm between idle and wot correct?

He could keep it SD but the chip thing is gonna be a hard deal as the cost to constantly change as he change adds up.

What your talking about is an alpha N system which most of these will do but that is really only for a full race-car.

What FAST,MS,BS3 etc.., do is a rpm vs kpa(map sensor) table which is then adjusted from all the sensors.

[351wStang]

Cool. Thanks for the explanation.

[InUrHead]

Been wrong before, but it's my understanding that the A9P (5.0 w/auto) brain box has a slightly more aggresive table in an attempt to make up for the slothlike trans, and can be used in a manual with no unintended side effects.