Biggest injectors you can run on stock ecu?

Are you able to run the holley ev1 66lb injectors on a stock 1989 mustang ecu. Currently running 42lb injectors changing over to a turbo setup going for 800rwhp. What I understand the 42lbs are only good for 550rwhp. Ecu is all factory just running a 6al box with btm and a fmu with a 255 in tank.
 
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First off 66lb injectors will be at the cusp of what you’d want for 800whp. 80 would be more like it

Youre going to need way more then a 255 intank can provide .
The fmu should go bye bye as well .

Ideally you’ll want a chip burned at a minimum or to go to atleast a megasquirt ecu or a full on standalone ecu setup and harness .

I’m curious to know what the rest of this setup consists of to make 800 whp . You’re going to really have to spend money in more then a few places to keep it living at that power .
 
First off 66lb injectors will be at the cusp of what you’d want for 800whp. 80 would be more like it

Youre going to need way more then a 255 intank can provide .
The fmu should go bye bye as well .

Ideally you’ll want a chip burned at a minimum or to go to atleast a megasquirt ecu or a full on standalone ecu setup and harness .

I’m curious to know what the rest of this setup consists of to make 800 whp . You’re going to really have to spend money in more then a few places to keep it living at that power .
Would a stock ecu be able to run 80lb injectors? Pro m makes 75lb injectors with a mass air calibrated for them as well. Just don't know if the stock a9l ecu will work with them. The motor is a stock 89 mustang 302 block with a x cam. Edlebrock performer heads with 2.02 valves ,1.6 rockers, arp head studs with lock wire gaskets. Msd ignition system 6al with btm and msd distributor. On3 turbo kit with upgraded turbonetics 76mm turbo and waste gate. Planning on running 30psi with c16 only. Should have mentioned i have a boost a pump as well. Just don't want to put the extra money out for a stand alone with a stock block build. I know I should be running a aeromotive fuel system with a Holly efi and a dart block but unfortunately moneys a factor.
 
Stock ECU is good for 19s, that’s it. With your proposed HP goal you really shouldn’t be playing the calibrated MAF game. A tune should be in the game plan in which the stock ECU will be tuned for the combo and injector size, or go aftermarket EFI.

Tuning stock ECUs is slowly becoming obsolete. With the availability of aftermarket ECUs capable of much more, you should really give this some serious thought
 
If money’s a factor, then don’t waste your money on bigger injectors. How bad is it gonna hurt when your 800 hp power goal results in two busted ass four cylinder halves under the hood? I guess nobody here is even gonna attempt to say that there is no such thing as a stock block 5.0 capable of withstanding more than where you currently are, because the topic is constantly up for discussion. Your engine will fail just north of 500 whp due to lack of internal integrity. Nothing you can do to a stock block will change that. Block filler, main studs, main girdles,...... all of it will fall right out on the track just as sure as the sun’s gonna rise If you attempt that power level.
 
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Very ambitious, which is always a good thing. And always love seeing the underdog come out on top. But 800whp - regardless of engine performance - is tough to stick to the ground with our >3k lbs cars. I think $$$ when it comes to keeping any sort of traction past 600whp. And with a budget build in mind it sounds like you could be entering a realm of seriously overloading your pocket. What suspension are you running?
 
I'm probably the biggest fan of running the factory computer left around here.
I have personally seen the factory computer work fine with 60's no tune at 650rwhp.
I've heard of guys going to 700rwhp.

But to put it bluntly, nothing in your plan is sensible, including using the stock computer.
Not the stock computer, the x cam, stock block, boost a pump, the heads, pretty much nothing.
You are going to have to dial back that goal by about 50% if you want any shot in hell of it living past a dyno run.

You are going to need another $20,000 (at least) to hit 800rwhp.

Let me guess, the trans is a t5?

I'm going to save you some time and a hell of a lot of money.
Buy a vortech S trim, set your goal to 450rwhp and go from there.
Anything thing else is just a pipe dream for a guy on a budget.
 
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I'm probably the biggest fan of running the factory computer left around here.
I have personally seen the factory computer work fine with 60's no tune at 650rwhp.
I've heard of guys going to 700rwhp.

But to put it bluntly, nothing in your plan is sensible, including using the stock computer.
Not the stock computer, the x cam, stock block, boost a pump, the heads, pretty much nothing.
You are going to have to dial back that goal by about 50% if you want any shot in hell of it living past a dyno run.

You are going to need another $20,000 (at least) to hit 800rwhp.

Let me guess, the trans is a t5?

I'm going to save you some time and a hell of a lot of money.
Buy a vortech S trim, set your goal to 450rwhp and go from there.
Anything thing else is just a pipe dream for a guy on a budget.
But, he already has a Chinese turbo:shrug:
 
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I'm probably the biggest fan of running the factory computer left around here.
I have personally seen the factory computer work fine with 60's no tune at 650rwhp.
I've heard of guys going to 700rwhp.

But to put it bluntly, nothing in your plan is sensible, including using the stock computer.
Not the stock computer, the x cam, stock block, boost a pump, the heads, pretty much nothing.
You are going to have to dial back that goal by about 50% if you want any shot in hell of it living past a dyno run.

You are going to need another $20,000 (at least) to hit 800rwhp.

Let me guess, the trans is a t5?

I'm going to save you some time and a hell of a lot of money.
Buy a vortech S trim, set your goal to 450rwhp and go from there.
Anything thing else is just a pipe dream for a guy on a budget.
No actually a c4. I just asked a simple question what has everyone seen a stock computer handle injector wise. Didn't ask about my pipe dream. I'll make sure to send a video with the numbers on a dyno.
 
Personally, I’m kinda curious to see it put together...But I need to find a way to turn this pic upside down.
1588858478557.jpeg
 
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Pretty much and high impedance injector can be ran into the stock eec, but it might start getting dicey unless you have a quarterhorse or something to actually tune it
 
Personally, I’m kinda curious to see it put together...But I need to find a way to turn this pic upside down.
1588858478557.jpeg

View: https://youtu.be/Gugwvfbo-iw
guess your not familiar with the project stock bottom end car. He's making 915whp with a Chinese turbo lmao. Motors been together for 4years. Maybe back in the 80s they would split at 500hp but nowadays a few guys are making this hp level.
 
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No actually a c4. I just asked a simple question what has everyone seen a stock computer handle injector wise. Didn't ask about my pipe dream. I'll make sure to send a video with the numbers on a dyno.
Can't wait to see it.
Just slap that turbo on and you will magically make 525rwhp more than you do now...
 
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Good luck in your goals. It's looks like your original question has been answered. I'm also looking forward to seeing the dyno numbers and curious to see how long it last. It's awesome that that guy in the vid is supposedly making that much HP on a stock bottom end and block for that amount of time. I'm relatively new to the performance side of messing with these cars, so I dont claim to have any special knowledge. What I have seen over and over since I started paying attention is that the stock blocks are only good for somewhere around 500 rwhp before they go pop. The technology is what it is with a 30 year old block. Just because we have better stuff we can bolt on and better equipment to tune with doesn't change the fact that the 30 year old block is a weak link in the setup. Aftermarket blocks designed to handle the stress of making big power is new tech. No stock fox came with a DART block in it from the factory.
 

View: https://youtu.be/Gugwvfbo-iw
guess your not familiar with the project stock bottom end car. He's making 915whp with a Chinese turbo lmao. Motors been together for 4years. Maybe back in the 80s they would split at 500hp but nowadays a few guys are making this hp level.

Yeah, and for that one example, there are dozens, hundreds, maybe thousands that died at half that power. There are guys claiming they got 250-350k miles or more on an engine too..I guess every engine goes that far before needing a rebuild then. But you do you, cause the odds are SOOO in your favor.
 
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View: https://youtu.be/Gugwvfbo-iw
guess your not familiar with the project stock bottom end car. He's making 915whp with a Chinese turbo lmao. Motors been together for 4years. Maybe back in the 80s they would split at 500hp but nowadays a few guys are making this hp level.


I think it's the longevity vs investment that some of us were keying in on.

Yes, out of a bag of 100 rubber bands, 16 will stretch a few more times than the others, and 3 will last stretch abnormally long. If they had a youtube, im sure they'd post about their accomplishments as well.

Your main concern was to not want to invest in a standalone vs stock ecu (~$1000?). I',m sure I'm off on that - but when pursuing 800whp... that kind of money is tossed around weekly - even after its built if you plan on taking full advantage of it as I'm sure anyone would.
 
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Are you able to run the holley ev1 66lb injectors on a stock 1989 mustang ecu. Currently running 42lb injectors changing over to a turbo setup going for 800rwhp. What I understand the 42lbs are only good for 550rwhp. Ecu is all factory just running a 6al box with btm and a fmu with a 255 in tank.
The stock block will split down the lifter valley somewhere between 450-500 HP. The 800 HP will require a Dart block to withstand that power level.
 
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View: https://youtu.be/Gugwvfbo-iw
guess your not familiar with the project stock bottom end car. He's making 915whp with a Chinese turbo lmao. Motors been together for 4years. Maybe back in the 80s they would split at 500hp but nowadays a few guys are making this hp level.

Not in the 80’s , still happens all the time . Lol
Yes he and a few others in the 8.2 deck group have been stupid fast with a stock block . Believe me just like the LS guys they won’t tell you it took more then 1 to get there .
The tuner better be touched by god too because If the engine sees the slightest bit of detonation it’s going to rattle itself apart .

Your fuel system even with a bap will be at its limit due to the fact that it seems by your posts you have Stock lines still . Can’t move fuel through a line that isn’t big enough to flow the volume you need to meet the demand of that power .C4s have been into the 8 second zone with some work so that I see happening .

I’ve personally ran 60lb injectors on a Anderson PMs and a stock ecu .

Moneys a factor for just about everyone and this :poo: don’t happen or come together over night . You know when money becomes a real factor though ? When god forbid the thing lets loose because you thought the guys on the internets were just acting like know it alls .
Good look on your journey I hope you reach your end goal with no issue .

Sincerely - someone who’s made 60 shy then your goal to the tire on pump gas on 11psi less of pressure .
 
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