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Installed my new MSPNP last week, been reading and researching, watching videos, etc, since just trying to take in everything. First time tuning so its a slow process, I know.

Currently going off a base 94-95 tune from DIY. I input my parameters into the calculator, 302 cid 24lb injectors 14.7 AFR, came up with a required fuel of 16.5. Start car, so rich it will hardly run.

Video I was watching earlier went over the ReqFuel for when using bigger injectors. Thought I already understood that part, until he put up a formula for required fuel rather than using the built in calculator. ReqFuel=OldInjector/NewInjector*OldReqFuel. So I punch in the numbers. 199.5/252*13.2=10.5. Start with a fresh base tune, put that number in, car actually starts and runs somewhat decent. Hmmmm....

Anyone else experience this? Did I do something wrong with the calculator?

Having fun with TunerStudio and MS so far, definitely just a lot to take in so any other helpful advice would be appreciated!
 

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Make sure the fuel pressure in the calculations is 39.5 to 40. A lot of cars use 43.
I'm not looking at TS right now, but I don't remember seeing anywhere to input fuel pressure?

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I haven’t used it in years, but I think the fuel injector data was rated at 43 psi vs the ford 40. Also make sure your injector wiring supports injector pulse (sequential, bank to bank) and some shot once per cycle or twice.
 

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Installed my new MSPNP last week, been reading and researching, watching videos, etc, since just trying to take in everything. First time tuning so its a slow process, I know.

Currently going off a base 94-95 tune from DIY. I input my parameters into the calculator, 302 cid 24lb injectors 14.7 AFR, came up with a required fuel of 16.5. Start car, so rich it will hardly run.

Video I was watching earlier went over the ReqFuel for when using bigger injectors. Thought I already understood that part, until he put up a formula for required fuel rather than using the built in calculator. ReqFuel=OldInjector/NewInjector*OldReqFuel. So I punch in the numbers. 199.5/252*13.2=10.5. Start with a fresh base tune, put that number in, car actually starts and runs somewhat decent. Hmmmm....

Anyone else experience this? Did I do something wrong with the calculator?

Having fun with TunerStudio and MS so far, definitely just a lot to take in so any other helpful advice would be appreciated!
Most of the Youtube videos are BS. Never seen that formula before, ignore it.

Base tune shouldn't be that far off. Required Fuel Calculator works just the way it's supposed to work. 16.5 is the correct number for your setup (I entered your numbers). Something else is wrong. You'll have to post up an msq file, but Corral doesn't allow it.

The MSExtra Forum is where you want to go for detailed help.
Megasquirt Support Forum (MSEXTRA) ? MS2/Extra, MS2, Microsquirt and Microsquirt module support (View forum)

Are you sure your MSPNPG2 is configured for 94-95? IIRC, there are some differences from the 87-93.
https://www.diyautotune.com/product/megasquirtpnp-g2-eec4b8-for-94-95-ford-mustang-5-0-manual-trans/
 

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Discussion Starter #6
Most of the Youtube videos are BS. Never seen that formula before, ignore it.

Base tune shouldn't be that far off. Required Fuel Calculator works just the way it's supposed to work. 16.5 is the correct number for your setup (I entered your numbers). Something else is wrong. You'll have to post up an msq file, but Corral doesn't allow it.

The MSExtra Forum is where you want to go for detailed help.
Megasquirt Support Forum (MSEXTRA) ? MS2/Extra, MS2, Microsquirt and Microsquirt module support (View forum)

Are you sure your MSPNPG2 is configured for 94-95? IIRC, there are some differences from the 87-93.
https://www.diyautotune.com/product/megasquirtpnp-g2-eec4b8-for-94-95-ford-mustang-5-0-manual-trans/
I'm just curious, because stock base tune it ran like ####. Went through the required fuel calculator and it ran even worse. Super rich to the point it would just die. Once I used the formula, whether it's right or not, the car actually idled pretty decent. Once warmed up AFR was right around 14-15. I'll check out the MSExtra forum. And I assume the ECU is configured for my car, at least that is what I ordered... Haven't opened it to verify jumpers are correct for 94-95

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Unless you really know what you're doing I would go with the calculated req fuel. You can recalculate your fuel table (VE table) to get the same result.

To recalculate the VE table highlight all the cells in it, then hit the 'X' icon at the top to 'Scale by'. Enter 0.6364 and click okay.

This will reduce the fuel in your VE table by the same amount you're experiencing by reducing your req_fuel from 16.5 to 10.5.
 

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Discussion Starter #8
Unless you really know what you're doing I would go with the calculated req fuel. You can recalculate your fuel table (VE table) to get the same result.

To recalculate the VE table highlight all the cells in it, then hit the 'X' icon at the top to 'Scale by'. Enter 0.6364 and click okay.

This will reduce the fuel in your VE table by the same amount you're experiencing by reducing your req_fuel from 16.5 to 10.5.
Hmm. Fair enough. I had started messing with the VE table in the just idle range. Scale it down by 5-10% at a time until it was idling decent with good AFR.

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Do you actually have a "basic" engine?
You said 302 with 24lb injectors. Nothing else?
Are you sure you have no vacuum leaks? The MAP sensor will give a false reading if any leaks.
 

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Do you actually have a "basic" engine?
You said 302 with 24lb injectors. Nothing else?
Are you sure you have no vacuum leaks? The MAP sensor will give a false reading if any leaks.
No, it's got heads, cam, and intake, no vacuum leaks. I'm comparing it to when I ran it on a bone stock tune when I first bought the car, before it was actually tuned. Ran and drove fine, although ran rich. Not rich enough to make it die at idle though. I have no datalogs or msq files, other than a base tune from DIY with adjusted required fuel.

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If just getting started, use the calculator.

Sometimes while tuning the car in, if you find the wohle tune to be rich or lean on average, you may tweak the reqFuel to bring the VE table into a range you like better.
If you have already tuned it and tweaked the reqFuel in the process, then it may be closer to scale reqFuel by the injector size change.

newReqFuel = currentReqFuel * (oldInjectorSize/newInjectorSize)
 

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Had the same issue, make sure your injectors are the correct size, make sure the don't need to be cleaned. Had a crap set of new injectors and would barely run. Put in a good set of Ford 42's and it was way better but the "base" tune took a lot of work to run well. Car is stock heads/cam and turbo. Runs like a stocker now.
Just takes time and patience. I sold this car to my friend 11 years ago and he got turbo bug a couple years ago and never got the tune very close. I bought it back a week ago, cleaned up the timing table which I had hand written based on A9L table. Set up the under boost timing like my Turbo Buick is. Got the AFR dialed in where I like it.
Make sure the timing and afr have smooth transitions with no big dips or humps. Had biggest issue with accel enrichment.
Now it will cruise in 5th @ 1k rpm
 
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