Engine Am I in Trouble? 331 Stoker Fuel.

Alright guys. So, I just put together a 331 stroker lower end while I had the engine out of my car. I'm running the GT40P Explorer intake and a decently hefty 0.550" cam. However, I am still on stock injectors. Will the car even run on the stock injectors and fuel pressure? Will it be too lean or will I get knocking and pinging or will the computer be able to compensate just enough? I plan on upgrading soon, but for right now, I need to know. Any input is appreciated.
Thanks!
 
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It will run...do you have a stock fuel pressure regulator ?

Do you have a wideband or AFR gauge ?

Running...even starting the engine lean can cause ring seat issues if it's a fresh bottom end. If not you should be able to start it with the vacuum line to the FPR off. This will increase fuel pressure. The 19lb factory injectors are not enough to safely drive the car. I do know people that have use 24lb injectors on 331 engines but their cam may have been tamer than yours.

The fuel system isn't the place to cheap out. If you are running lean it will make your life harder than it needs to be.

It's very hard to get the engine to stay running to adjust timing, idle, and check for leaks if your set up is going to be starving for fuel.
 
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It will run...do you have a stock fuel pressure regulator ?

Do you have a wideband or AFR gauge ?

Running...even starting the engine lean can cause ring seat issues if it's a fresh bottom end. If not you should be able to start it with the vacuum line to the FPR off. This will increase fuel pressure. The 19lb factory injectors are not enough to safely drive the car. I do know people that have use 24lb injectors on 331 engines but their cam may have been tamer than yours.

The fuel system isn't the place to cheap out. If you are running lean it will make your life harder than it needs to be.

It's very hard to get the engine to stay running to adjust timing, idle, and check for leaks if your set up is going to be starving for fuel.
Damn, that is a shame to hear. It's a stock FPR and a stock rail. I'm looking at 30lbs injectors now. Would 30lbs injectors and an adjustable FPR be enough to safely drive it if I bump up the pressure a little bit?
 
They should be safe without increasing the pressure.

What year is your car ?

The stock rail is fine for what you need. Don't have to worry about that until you start hitting around 450hp.

If you have the factory fuel pump it may become an issue. I recommend a 190lph pump....255lph would be better....you'd have room to grow.
 
Your car will need to be tuned somehow. Chip or stand alone like megasquirt or Stinger Pimpxs. The later being the most versatile. A microsquirt will run your set up easily but has less features. I run mspnp2 in my turbo fox.
 
They should be safe without increasing the pressure.

What year is your car ?

The stock rail is fine for what you need. Don't have to worry about that until you start hitting around 450hp.

If you have the factory fuel pump it may become an issue. I recommend a 190lph pump....255lph would be better....you'd have room to grow.
It's a 1990.

Okay, injectors are definitely a must, but the problem is, I'm seriously running out of money and time right now. I really cant afford a whole tuning setup. Will stock run fine for now at least with the 30lbs injectors?
 
It's a 1990.

Okay, injectors are definitely a must, but the problem is, I'm seriously running out of money and time right now. I really cant afford a whole tuning setup. Will stock run fine for now at least with the 30lbs injectors?
Looks like I also have the cash for the fuel pump and pressure regulator as well. Though, there is no way I'll be able to pull off getting a tuner. Will having the stock tune potentially run the new injectors lean and grenade it anyways?
 
Your car will need to be tuned somehow. Chip or stand alone like megasquirt or Stinger Pimpxs. The later being the most versatile. A microsquirt will run your set up easily but has less features. I run mspnp2 in my turbo fox.
Though, on that same note, how far do I have to go with the tuning? Would a Bama plug in do the job well enough without a full tuning suite?
 
Though, on that same note, how far do I have to go with the tuning? Would a Bama plug in do the job well enough without a full tuning suite?
I just did some reading, and apparently, the Bama chips dont cover stroking. I'm at a loss, is the tune going to make or break the build? I apologize for the frantic posts, I'm kinda coming down to the wire and I'm stressed to get this thing done within my budget that rapidly shrank.
 
With the injectors you will need a matching MAF meter. You really could use the factory FPR.

The micro squirt isn't that bad. Best bang for the buck. This replaces the stock ECU and is tuned by laptop.

Screenshot_20200228-000439_Chrome.jpg


This thing will need to be wired into your harness but there are tons of guys here that can help with this.

To run successfully you will need

1. Megasquirt

2. 255lph fuel pump ( my 340lph came from amazon less than 80 bucks....340 was overkill I should've gone with 255lph )

3. 30lb injectors

4. Wideband o2 sensor ( I use an lc2 wideband )

You don't need the MAF with microsquirt. That makes it almost pay for itself. This microsquirt will run just about any v8 that doesn't have vvt. 302...to big block chevys. Will run your lawn mower too.

If you are serious about getting the car running right @a91what can help you get the right parts.

With the microsquirt you can get the injectors off a chevy truck. They are all over the interweb and 47lb.

These things will nickel and dime ya to death, man. Time is the other issue...wiring in the microsquirt and wideband will take time.

The 30 lb. Injectors with FP and MAF would get you running but I wouldn't beat on it without some type of tune.

I had a 347 with 30lb injectors, matching MAF, an e cam and no tune in my 89. It ran but would burn your eyeballs out. I drove it around like that. It didn't blow up. The fuel pump was a 190lph. If your car is a stick it will be easier to drive without a tune because you can control the rpm better with your right foot. Expect some bucking a weirdness but it shouldn't blow up.
 
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With the injectors you will need a matching MAF meter. You really could use the factory FPR.

The micro squirt isn't that bad. Best bang for the buck. This replaces the stock ECU and is tuned by laptop.

Screenshot_20200228-000439_Chrome.jpg


This thing will need to be wired into your harness but there are tons of guys here that can help with this.

To run successfully you will need

1. Megasquirt

2. 255lph fuel pump ( my 340lph came from amazon less than 80 bucks....340 was overkill I should've gone with 255lph )

3. 30lb injectors

4. Wideband o2 sensor ( I use an lc2 wideband )

You don't need the MAF with microsquirt. That makes it almost pay for itself. This microsquirt will run just about any v8 that doesn't have vvt. 302...to big block chevys. Will run your lawn mower too.

If you are serious about getting the car running right @a91what can help you get the right parts.

With the microsquirt you can get the injectors off a chevy truck. They are all over the interweb and 47lb.

These things will nickel and dime ya to death, man. Time is the other issue...wiring in the microsquirt and wideband will take time.

The 30 lb. Injectors with FP and MAF would get you running but I wouldn't beat on it without some type of tune.

I had a 347 with 30lb injectors, matching MAF, an e cam and no tune in my 89. It ran but would burn your eyeballs out. I drove it around like that. It didn't blow up. The fuel pump was a 190lph. If your car is a stick it will be easier to drive without a tune because you can control the rpm better with your right foot. Expect some bucking a weirdness but it shouldn't blow up.
Thanks for your input, man, I'll look into it. I should have just stuck with a 302, I didn't know what I was getting myself into and I have really screwed myself. I absolutely cannot afford any sort of tuning system, even at that price and the cheapest MAF I could find was $200. I guess I'll try to scrape together what I can to get a MAF just to get it running without blowing up. The anecdote of you driving yours without a tune certainly makes me feel a bit better.
 
With the injectors you will need a matching MAF meter. You really could use the factory FPR.

The micro squirt isn't that bad. Best bang for the buck. This replaces the stock ECU and is tuned by laptop.

Screenshot_20200228-000439_Chrome.jpg


This thing will need to be wired into your harness but there are tons of guys here that can help with this.

To run successfully you will need

1. Megasquirt

2. 255lph fuel pump ( my 340lph came from amazon less than 80 bucks....340 was overkill I should've gone with 255lph )

3. 30lb injectors

4. Wideband o2 sensor ( I use an lc2 wideband )

You don't need the MAF with microsquirt. That makes it almost pay for itself. This microsquirt will run just about any v8 that doesn't have vvt. 302...to big block chevys. Will run your lawn mower too.

If you are serious about getting the car running right @a91what can help you get the right parts.

With the microsquirt you can get the injectors off a chevy truck. They are all over the interweb and 47lb.

These things will nickel and dime ya to death, man. Time is the other issue...wiring in the microsquirt and wideband will take time.

The 30 lb. Injectors with FP and MAF would get you running but I wouldn't beat on it without some type of tune.

I had a 347 with 30lb injectors, matching MAF, an e cam and no tune in my 89. It ran but would burn your eyeballs out. I drove it around like that. It didn't blow up. The fuel pump was a 190lph. If your car is a stick it will be easier to drive without a tune because you can control the rpm better with your right foot. Expect some bucking a weirdness but it shouldn't blow up.
Yeah, so looking at it, I think I'm going to go with the adjusted MAF for now alongside the 30lbs injectors and a 255lph pump. It's the cheapest, quickest option I could find. I'm sorry that this has been such a terrible, frantic thread. You've certainly helped me get my head straight and figure out what I need.
 
Let me comment here, I'm no builder of big power but I have been around the block. If funds are short you need to consider where to spend the money and why.
Buy the injectors, maf and fuel pump and limp around with the stink and bucking at low rpms or wait for the funds or a deal on the stuff that gets it running right. The bucking alone will drive you bat sht crazy and be very hard on drive line parts, it will also be embarrassing when driving.
Getting the stand alone ecu with tuning capabilities, injectors and fuel pump (when funds allow) will be spending money once and is actually the more cost effective plan.
JMO and not based on any real mechanical experience.
 
Let me comment here, I'm no builder of big power but I have been around the block. If funds are short you need to consider where to spend the money and why.
Buy the injectors, maf and fuel pump and limp around with the stink and bucking at low rpms or wait for the funds or a deal on the stuff that gets it running right. The bucking alone will drive you bat sht crazy and be very hard on drive line parts, it will also be embarrassing when driving.
Getting the stand alone ecu with tuning capabilities, injectors and fuel pump (when funds allow) will be spending money once and is actually the more cost effective plan.
JMO and not based on any real mechanical experience.
Thanks man. I would take the time and wait until funds allow me to go ahead and get the tuning system, however, I am shipping out to Ohio for an education program and I wont be able to work as much and the car will likely stay at home. It has to be able to be started and moved, though and I'm leaving in a week, which is why I'm stressed to get it finished. I would love to go with the standalone ECU, but I simply dont have the time or money for that right now. Definitely in the future, though. Thanks guys.
 
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