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Topic: fuel injectors for high boost? (Read 1914 times) previous topic - next topic

fuel injectors for high boost?

i want to up grade my fuel system so i can pump out more boost. around 23-25 lbs of boost out of a t3 t4. im getting a 255lph walbro fuel pump, bbk fuel regulator but im curious on what size fuel injectors i should get. thank you for your help
1988 LX coupe. a dressed up motor with full exhaust and BBK shorties with flowmasters, BBK CAI, accufab 65mm tb, HO upper intake, cobra valve covers.

fuel injectors for high boost?

Reply #1 –
65#
[SIGPIC][/SIGPIC]1988 Turbo Coupe 19psi ,K&N Cone TurboBack 3in Exhaust , Ported Big Valve Head w/ Bo 1.5 , Stinger short throw

fuel injectors for high boost?

Reply #2 –
You will not be able to just throw some 65# injectors in it and go.  You'll need some way to tune the ECU for the new injector size.
88 TC 5speed, 168000+ miles, stock 2.3T long block, ported RFE6 exhaust, Evergreen T3 running 15#'s.
Up next: FMIC, fresh air intake, ported intakes, ported big valve head.

fuel injectors for high boost?

Reply #3 –
42lb er's and a tune.
 

fuel injectors for high boost?

Reply #4 –
what tuner can i use? i heard about some piggy back tunner from turbocoupetgill. does anyone know where i can pick one up?
1988 LX coupe. a dressed up motor with full exhaust and BBK shorties with flowmasters, BBK CAI, accufab 65mm tb, HO upper intake, cobra valve covers.

fuel injectors for high boost?

Reply #5 –
If you want to be able to tune "real time, on the fly", I've heard good things about the Moates Quarterhorse.  This way you won't have to pull the chip and reflash it everytime you want/need to make a change. You'll still need software to tune with. Moates should be able to help you out with the whole package.  The prices there seem reasonalble, and enough people use them, so support is good.
88 TC 5speed, 168000+ miles, stock 2.3T long block, ported RFE6 exhaust, Evergreen T3 running 15#'s.
Up next: FMIC, fresh air intake, ported intakes, ported big valve head.

fuel injectors for high boost?

Reply #6 –
Quote from: dominator;292288
42lb er's and a tune.


You can max out 42lbs injectors with least a stock T3. Need at least 65lbs injectors.
It's Gumby's fault.

my $.02

Reply #7 –
Get over to TF, check out the proven combos, and copy the one that best fits your goals and budget.
__________________
Twin '85 TCs
White/ Grey 2-tone
#1 (left): undergoing top-to-bottom rebuild     
#2 (right): DD, power everything (sorta)
[SIGPIC][/SIGPIC]

fuel injectors for high boost?

Reply #8 –
:iagree:Good advice. Would've never thought of that.
88 TC 5speed, 168000+ miles, stock 2.3T long block, ported RFE6 exhaust, Evergreen T3 running 15#'s.
Up next: FMIC, fresh air intake, ported intakes, ported big valve head.

fuel injectors for high boost?

Reply #9 –
Quote from: Tbird232ci;292478
You can max out 42lbs injectors with least a stock T3. Need at least 65lbs injectors.

O ok 42lber's are good for 500+hp.
I run them in my 302 with 500+ with no problems and an 80% duty cycle.

You'll be fine with 42s.
65s are good for over 800hp,you don't need those.

fuel injectors for high boost?

Reply #10 –
Quote from: dominator;292560
O ok 42lber's are good for 500+hp.
I run them in my 302 with 500+ with no problems and an 80% duty cycle.

You'll be fine with 42s.
65s are good for over 800hp,you don't need those.


Ummm, except he's got half the number of fuel injectors? Divide all your numbers by 2 and keep in mind that high boost needs more injector to run right at all (with tune).
1988 Thunderbird Sport

fuel injectors for high boost?

Reply #11 –
Agreed.
So half of a 5.0L is 2.5L's right.
Therefore 42s should support in the neighbourhood of around 250-275hp on a turbo'd 4cyl.
That should be where he will be around upgrading the turbo and boost numbers.
Even if it was slightly higher that could easily be adjusted with an adjustable fuel pressure regulator,not to mention the factory regulator is boost sensitive and up's the pressure equal to boost,up'ing the injectors output quite a bit under boost.
55's would be the next bet but 65s are still just to big for the application.
If you can get away with the stock 36's on 18lbs of boost from the stock T3 42s should be sufficent.

fuel injectors for high boost?

Reply #12 –
IIRC, 42's with boost at those levels are also at pretty high duty cycles. You'd want at least 20% on top of whatever you need. I agree that 65 is a bit much but 42's may be too small.

I'm not sure what was up with the early SVO's but Ford gave these things 36lb injectors for 190hp. It doesn't take long to see that it's a good idea to use more than 42's.
1988 Thunderbird Sport

fuel injectors for high boost?

Reply #13 –
Quote from: dominator;292560
O ok 42lber's are good for 500+hp.
I run them in my 302 with 500+ with no problems and an 80% duty cycle.

You'll be fine with 42s.
65s are good for over 800hp,you don't need those.


A 302 and a 2.3L are total different beasts. Cut the amount of injectors in half, while keeping the same amount of power, and what happens? You double your duty cycle. So then you think, chop your power in half, 250+, 4 of those same injectors are then working at an 80% duty cycle. You can get away with adding pressure, but as you add pressure, your spray pattern suffers.

Not to mention, 42# injectors for your V8 are high impedance.

On a turbo 2.3L, 65# injectors are good for about 400-450.
It's Gumby's fault.

fuel injectors for high boost?

Reply #14 –
Did not know about the impedance differance but there should be something smaller out there for the low impedance, from what i understand the low systems can use both.
He won't be pushing that kind of power by just upping the boost and not doing anything else so i figure he'll be just shy of 300hp.
The stock regulator ups the pressure under boost anyways 1psi-1lb of boost so running 25 pounds of boost should raise the pressure the same over base allowing for more fuel flow.