331 and stock Mustang EFI/intakes

[malcolmzilla]

Would a stock Mustang EFI setup (intakes, MAF, F250 pump) flow enough (with larger injectors) to run a mild 331?

I searched some threads saying a custom tuning and ECU flash will be needed as well. Just curious as my smogger 302 with 470 TA is a dog, and I am debating upgrade options, 5.0 EFI donor, or build one (CHP has mild 331 longblocks for $4500...)

Thanks.

 

[justinoshea]

Would a stock Mustang EFI setup (intakes, MAF, F250 pump) flow enough (with larger injectors) to run a mild 331?
.

for the most part, yes. ideal? No. A 331 is only 10% bigger.

I searched some threads saying a custom tuning and ECU flash will be needed as well. Thanks.

No, a custom tune is only needed for radical cams and setups. the MAF will tell the ECU how much fuel to add. my 347 runs fine with or without a custom tune and the only stock parts left are the valve covers.

 

[Broncobowsher]

A stock 351 will just bearly run on a stock mustang 19 lb injectors.

Most 331's have a decent cam and good flowing heads. Stuff that will outflow a stock 351 without even thinking of it.

So to answer the question, yes the 331 will start, run and drive around on a stock mustang 19 LB injectors and EFI. But you couldn't get on it as it will run out of MAF and injector well before the top end arrives. Next choke point, the stock 5.0 intake. But a junkyard Explorer intake will take care of that. 24lb injector should be enough with a matching MAF and correctly chipped EEC.

 

[malcolmzilla]

Thanks guys, more reading required, what's a fair price for a stang efi setup less the long block?

 

[basher13]

I have a set up, complete from a 94 mustang that needs to go away. If you figure out a price and are interested let me know. Bought the car after it was wrecked and I just want the motor and trans, less the injection, it's still on the car waiting for time to pull it.

 

[malcolmzilla]

So, in a stock stang EFI on a 331;

- use the harness, fuel rail, regulator and system, knock sensor, temp sensor, CPS, tps, o2 sensor ECU (89-93 manual trans), relays, replace components as necessary

- ignition???

- based on the o2 sensor, the 19 lbers would pulse longer and prolly run out at higher rpms, thus the need for the 24's, F250 pump should keep up?

- higher rpms maf will not register flow correctly, plus with a cam and good heads making this worse, what about the throttle body?

- stang intake is an air bottleneck, explorer flows enough?

- plus good headers - are the explorer ones ok?

- ECU reflash, esp, for cam and head improvements?

 

[justinoshea]

Basically the stock 225hp mustang induction system is (although very well matched combination) too small for a mild to medium 331. you will need to upgrade just about everything to get back to a well match combo for said motor, which will cost 5-10 grand (especially if you start with a $4500 long block) depending on what you want to do.

 

[mr.n]

You'll need that 331 to breath a little better.
The stock stang does well, but improving air flow is the key for power.
I'd suggest a good heads, intake like a GT40 or Explorer, Larger Throttle body, and Headers.


I've an explorer upper, lower, TB 65mm with taps for the ECT & ACT. It's almost bolt on. $150
http://littlekeylime.com/MrN/img/Engine/Explorer_intake_upper_III_12.jpg

 

[mr.n]

So, in a stock stang EFI on a 331;

- use the harness, fuel rail, regulator and system, knock sensor, temp sensor, CPS, tps, o2 sensor ECU (89-93 manual trans), relays, replace components as necessary

- ignition???

- based on the o2 sensor, the 19 lbers would pulse longer and prolly run out at higher rpms, thus the need for the 24's, F250 pump should keep up?

- higher rpms maf will not register flow correctly, plus with a cam and good heads making this worse, what about the throttle body?

- stang intake is an air bottleneck, explorer flows enough?

- plus good headers - are the explorer ones ok?

- ECU reflash, esp, for cam and head improvements?

- Yes, Mustang wiring and computer work well. (No knock sensor)

- ignition Stock will do well. My brother had a 10 second stang that the MSD fried out so many times he ran the stock ignition a few time.

- if you get 24, you need to get a matching MAF. That engine can rev high, if you plan on this 24 can be found used for cheap.

- Factory MAF is ok and does well. However it's small opening is more of a reason to upgrade.

- if You've heads and headers the stock intake is a huge problem. It can be ported, however a ported stang lower flows about the same as a stock Explorer/GT40.

- Cam I'm not sure, but make sure to match your cam with heads. Don't guess this one by your self, and also match the head springs.

- Yes the explorer flows enough. You can always port the bottom, however they are the best deal going if you ask me. I've one waiting for my new heads...

- Explorer headers suck! Lots of threads on what to run in an EB with GT40 or GT40p heads.

- A tune is always good. You can buy stuff to hook to your laptop and tune it your self... I've heard good things about TSM.

 

[malcolmzilla]

Thanks guys, I guess I'll look for the 89-93 Mustang system complete, and go from there depending on what I do for an engine, seems for anything past stock Mustang one should count on adding larger MAF, injectors and intake, headers, especially with heads and stroking it.

 

[needabronco]

Not sure if this has been said yet but, I'd look into a 96-01' explorer GT40 intake, they flow supposedly within 5% of a Cobra intake, already have a better fuel rail 19lb injectors, and bigger throttle body. I use an A9L computeran ,and a MAF from a GT, which both match the injectors. I don't have a stroker, but I'd say my engine runs alot better, that when carb'd...

 

[57baja]

Basically the stock 225hp mustang induction system is (although very well matched combination) too small for a mild to medium 331. you will need to upgrade just about everything to get back to a well match combo for said motor, which will cost 5-10 grand (especially if you start with a $4500 long block) depending on what you want to do.

Why do you need to upgrade everything? A kenne bell blower will give huge power increases on a bone stock 5.0 with the only thing besides blower is an fmu to spike fuel pressure under boost.The stock system is handling approx. 80 hp gain so why do adding some extra cubic inches need everything else upgraded??:?

 

[Broncobowsher]

Why do you need to upgrade everything? A kenne bell blower will give huge power increases on a bone stock 5.0 with the only thing besides blower is an fmu to spike fuel pressure under boost.The stock system is handling approx. 80 hp gain so why do adding some extra cubic inches need everything else upgraded??:?

A kenne bell blower get around it by overpressurizing everything. I believe there is abooster pump in the system as well. Stock lower and heads suck, but they can still move air if it is pushed through them. Hence the blower. If you were to put that blower on a good flowing engine the boost would drop and the power go up. Boost is the lack of flow due to restrictions.

While not everything need upgradding to run EFI on a good breathing 331, there are several items that should see attention.
Stock fuel rails will probably be fine
19 LB injectors won't
Stock 5.0 intake is a choker, but a junkyard Explorer should be fine
Stock 60mm 5.0 throttle body is small, but junkyard 65 is a good starting point.
Stock '88 to '93 MAF is a choker.
Thr F250 fuel pump will probably do fine.
The computer program will need updating as well, at this point not a single parameter programed into it is right. Everything from the MAF curve, injector size, engine displacment, intake volume and a few more are all going to be wrong. There are surface bandaids (like a FMU for a supercharger) to skirt the correct repair of just programming all the parts to match.

 

[mkaenel]

quick question...sorry for the hijack.

Can you run larger injectors (24), throttle body and MAF on a pretty well built 302 in anticipation of doing a stroker later.

I just want to avoid having to buy everything (EFI parts) for the 302 when I plan on doing a 347 stroker later. I would like to use the same EFI parts for the stroker.

Maybe the ECU just need a reprogram?

Thanks,

Matt

 

[Broncobowsher]

You can.

 

[57baja]

A kenne bell blower get around it by overpressurizing everything. I believe there is abooster pump in the system as well. Stock lower and heads suck, but they can still move air if it is pushed through them. Hence the blower. If you were to put that blower on a good flowing engine the boost would drop and the power go up. Boost is the lack of flow due to restrictions.

While not everything need upgradding to run EFI on a good breathing 331, there are several items that should see attention.
Stock fuel rails will probably be fine
19 LB injectors won't
Stock 5.0 intake is a choker, but a junkyard Explorer should be fine
Stock 60mm 5.0 throttle body is small, but junkyard 65 is a good starting point.
Stock '88 to '93 MAF is a choker.
Thr F250 fuel pump will probably do fine.
The computer program will need updating as well, at this point not a single parameter programed into it is right. Everything from the MAF curve, injector size, engine displacment, intake volume and a few more are all going to be wrong. There are surface bandaids (like a FMU for a supercharger) to skirt the correct repair of just programming all the parts to match.

I agree with you on what you said but the other post said you need to spend a few grand to upgrade everything.True the blower forces air making more power and a stroker will also increase air flow.Adding better heads,inj.,tb,intakes should all enhance power on blown or stroked motors.His original question was could the stock components work on a 331 and yes they will stock 19# inj can support 300hp. If it were me I and I could'nt afford everything run the stroker with stock everything then wait until you can pick up all the other add ons. Whoever is buliding the 331 buy Richard Holdner's 5.0 book.It runs dyno tests on every aftermarket component you can think of on a 5.0 from stock to radical showing exactly what the combo's can or can't do,I used it when I built my 5.0 kenne bell for my bronco.;D