24 or 30 injectors???

[casillas5.0]

Hi again. This is the combo on my 89 coupe:

Stock short block
World Windsor Jr iron heads (1.94/1.6)
TF stage 1 cam
Comp 1.6 SS RR
Edelbrock Performer intake
70mm BBK throttle
76mm C&L MAF
1 5/8 Hedmann headers
2 1/2 exhaust with Flowmaster pipes

This combo needs 30 pound injectors or with 24's is enough?

Possible future changes:
2.02/1.6 heads
TF stage 2 cam
bored block


Thanks for your comments

[garycrist]

What ever is cheapest. You are close to the top half of the 24's. In the future the 30's.

[2cammer97]

24 lb injectors are plenty of injector for any stock shortblock 5.0 with H/C/I.

You can always get 30 lb injectors and have "room to grow" but I never really think it's wise to buy parts that do this. Build your car optimally for it's current setup. Even with your future changes 24 lb injectors would be fine.

Marcus

[Joel5.0]

30 libras..... I mean, pounds.

[2cammer97]

Just to give you an example: My best friend's '92 LX Hatch had a stock rebuilt 302 (notched stock pistons) ~9.9:1 CR, AFR 185 heads, FTI cam, Edelbrock Performer RPM intake, BBK Longtubes, etc. It ran 11.9 at 114 mph, dynoed 320 rwhp / 350 rwtq, and 24 lb injectors were plenty of fuel for it.

Marcus

[BHAM]

30 is to big, unless you get a tune. Stick to the 24's


Sent from my iPhone using Tapatalk

[Joel5.0]

Originally Posted by BHAM

30 is to big, unless you get a tune. Stick to the 24's


Sent from my iPhone using Tapatalk

Done right?..... nope, they are not too big + a fuel injector at a low FPW is a happy injector for a long time, BTSTDT a few times.

[2cammer97]

Originally Posted by Joel5.0

Done right?..... nope, they are not too big + a fuel injector at a low FPW is a happy injector for a long time, BTSTDT a few times.

For that matter maybe he should just stick 42 lb injectors in there and call it a day.

Fact, 24 lb injectors will safely flow enough fuel for his combo (current and future) and will last a long time. His car should put down around 280-300rwhp. There is no need to run 30 lb injectors at that power level. BHAM is right, make sure the MAF is spot on for the 30's or else you will need to get a tuned chip done. The car will be rich at idle otherwise and not idle or drive as smooth.

Marcus

[Joel5.0]

Originally Posted by 2cammer97

For that matter maybe he should just stick 42 lb injectors in there and call it a day.

Fact, 24 lb injectors will safely flow enough fuel for his combo (current and future) and will last a long time. His car should put down around 280-300rwhp. There is no need to run 30 lb injectors at that power level. BHAM is right, make sure the MAF is spot on for the 30's or else you will need to get a tuned chip done. The car will be rich at idle otherwise and not idle or drive as smooth.

Marcus

Nope.... maybe 60 pounders would be a better choice then..... Love it when things are given the "exaggerate to try to make a point" w/out having the full picture of the case. So injectors are rated in pounds and HP? Wonder why 306 setups that have been datalogged at the dyno and the track, not making the "injector HP rating", are found to be at 100% duty cycle. BTW.... using RWHP numbers is not correct, since the HP formula is the only thing preached like the gospel, lets use your 280-300 RWHP figures:

280-300 RWHP is ~338 or 361 FWHP...(using a 17% drive train loss). Now, using the Injector size = (HP x BSFC) / (number in injectors x duty cycle) formula.

(338 or 361 hp x .5 BSFC) / (8 inj x .8 duty cycle) = 169 or 180.5 / 6.4 = 26.4 or 28.2

Anyway.... back to reality.... Casillas, 30# injectors @40 psi fuel pressure are NOT too big for your plans, as I have said/experienced like in this example, done right they will work fine + why run the chance of having to buy another set?

[justhereforinfo]

What size injector is the C&L maf "calibrated" for?

Do you plan to have the setup tuned?

I only ask because my 347 setup is using a 24lb injector being controlled by a moates chip, and even though the injector duty cycle may be high, they supply enough fuel to put my afr into the 11's. This wasnt the case when I ran the cobra maf/cobra 24's/cobra ecm. The afr was in the high 13's without the moates.

[BHAM]

Originally Posted by Joel5.0

Nope.... maybe 60 pounders would be a better choice then..... Love it when things are given the "exaggerate to try to make a point" w/out having the full picture of the case. So injectors are rated in pounds and HP? Wonder why 306 setups that have been datalogged at the dyno and the track, not making the "injector HP rating", are found to be at 100% duty cycle. BTW.... using RWHP numbers is not correct, since the HP formula is the only thing preached like the gospel, lets use your 280-300 RWHP figures:

280-300 RWHP is ~338 or 361 FWHP...(using a 17% drive train loss). Now, using the Injector size = (HP x BSFC) / (number in injectors x duty cycle) formula.

(338 or 361 hp x .5 BSFC) / (8 inj x .8 duty cycle) = 169 or 180.5 / 6.4 = 26.4 or 28.2

Anyway.... back to reality.... Casillas, 30# injectors @40 psi fuel pressure are NOT too big for your plans, as I have said/experienced like in this example, done right they will work fine + why run the chance of having to buy another set?

30 will be to big for his setup, and without a tune it will have less performance. Why is it that everyone thinks bigger is better. Stick with 24, your combo in now way shape or form needs 30's. You could prolly even get away with 19's. They will support alot more power then you think.

The simple fact is your combo will not need 30. Intake and cam will Peter out around 5500. Heads "should "pull to 6500-7000. Even If you wind it up to try to get the rpm that could use the 30's the cam, intake and PCM wouldn't let it get there. Remember you will never spin that motor over 6250 rpm without modding the PCM rpm capabilities .


Sent from my iPhone using Tapatalk

[BHAM]

Just FYI , even the 93 cobra with better flowing heads, tb, intake was over injected from the factory. The 24's were to much for that setup.


Sent from my iPhone using Tapatalk

[WHITEMACH]

made 325.7rwhp with the 19s,,,,i would say 24s

[BHAM]

Originally Posted by WHITEMACH

made 325.7rwhp with the 19s,,,,i would say 24s

Awesome numbers. You might even gain with some 24's


Sent from my iPhone using Tapatalk

[Joel5.0]

Originally Posted by BHAM

30 will be to big for his setup, and without a tune it will have less performance. Why is it that everyone thinks bigger is better. Stick with 24, your combo in now way shape or form needs 30's. You could prolly even get away with 19's. They will support alot more power then you think.

The simple fact is your combo will not need 30. Intake and cam will Peter out around 5500. Heads "should "pull to 6500-7000. Even If you wind it up to try to get the rpm that could use the 30's the cam, intake and PCM wouldn't let it get there. Remember you will never spin that motor over 6250 rpm without modding the PCM rpm capabilities .


Sent from my iPhone using Tapatalk

LOL..... Not being able to do it, or not have a little hands-on experience installing them to suit the needs of the engine across the whole RPM range, not its preconceived RPM ceilings by component, doesn't automatically presupposes it as not possible...... or a "bigger is better" type of approach generalization as so wrongly presumed.

Originally Posted by BHAM

Just FYI , even the 93 cobra with better flowing heads, tb, intake was over injected from the factory. The 24's were to much for that setup.


Sent from my iPhone using Tapatalk

Yup.... the whole Ford engineering department was fired, specially after also using 24# injectors in truck and SUV engines.

[92Christine]

I'm in this delema as well...to much to type here. Had 30 pounders, chip and a tune...never really got the tune thing worked out. Ended up putting the 19 pounders back in and pulled the chip...car is pulling much stronger and driveability is excellant. I go back to the tuner Wednesday with the 19 pound set up. We'll see how it does on the dyno and go from there. If the A/F looks good I'm probably just going to leave the 19 pounders in there and either sell the injectors and chip or save them for another upgrade...i.e. supercharger.

I believe that the 19 pounders are enough for my set up...seen a number of folks here on the corral making 300RWHP with them..guessing I'm in the 275RWHP. I'm not saying that 30 pounders can't be tuned to work but the throttle response, drivaeability, etc. with the 19's is really good.

Keep in mind going with 30lb injectors is expensive...$250 for new injectors, $40 cal tube, and around $600 for the tune (chip, dyno, tax, etc.). My advice is to put the 19's in and spend a couple of buck on the dyno pulls...if the Air/Fuel looks good call it a day and use the $750 ($900 parts-$150 Dyno) for something else.

P.S. I have/had the C&L meter with the 30lb tube...you'll hate it and need a tune...others will tell you to ditch the C&L...do a couple of searches and you'll find company.

Good luck.

[BHAM]

Originally Posted by Joel5.0

LOL..... Not being able to do it, or not have a little hands-on experience installing them to suit the needs of the engine across the whole RPM range, not its preconceived RPM ceilings by component, doesn't automatically presupposes it as not possible...... or a "bigger is better" type of approach generalization as so wrongly presumed.



Yup.... the whole Ford engineering department was fired, specially after also using 24# injectors in truck and SUV engines.

Think what you want say what you want. The truth is 19 would be better for that combo then the 30's would. Keep bench racing and crunching numbers it makes your car fast. Here in the real world and this case that doesn't apply

It is in FACT the 24's in the cobra were OVERKILL!


Sent from my iPhone using Tapatalk

[WHITEMACH]

ford did overkill 93-95 cobras with the 24s.....put them in my car lost 14rwhp,,,took them right out to

[BHAM]

Originally Posted by WHITEMACH

ford did overkill 93-95 cobras with the 24s.....put them in my car lost 14rwhp,,,took them right out to

Exactly. Just for reference, mustang 5.0 technical reference and performance handbook-page 120, chapter 4.6 titled " cobra electronic fuel injection"
" the use of 24lb/hr injectors inthe (93-95) production cobra engine was intended to provide reserve capacity in EXTREME OPERATING CONDITIONS. But because they are being utilized for only a small portion o their capacity most of time, the high rate injectors in this OE application may be considered OVERKILL.

Just sayin

Sent from my iPhone using Tapatalk

[foxrodsinc]

Originally Posted by WHITEMACH

made 325.7rwhp with the 19s,,,,i would say 24s

but how much duty cycle? i do believe 30 atomize better than 24's. also, when you change combo's the larger injector will be there. do the 30's.

[foxrodsinc]

Originally Posted by WHITEMACH

ford did overkill 93-95 cobras with the 24s.....put them in my car lost 14rwhp,,,took them right out to

then you needed a tune or a new tuner.

[BHAM]

Originally Posted by foxrodsinc

but how much duty cycle? i do believe 30 atomize better than 24's. also, when you change combo's the larger injector will be there. do the 30's.

The 30 would not atomize the fuel better


Sent from my iPhone using Tapatalk

[foxrodsinc]

Originally Posted by WHITEMACH

ford did overkill 93-95 cobras with the 24s.....put them in my car lost 14rwhp,,,took them right out to

the problem with the cobras was the tune in the eec, not the size injector. maybe you needed to tune for the 24's or find a new tuner. with more fuel added induction side should be opened up.can't trow a part on and not make changes to work with it.

[foxrodsinc]

Originally Posted by BHAM

The 30 would not atomize the fuel better


Sent from my iPhone using Tapatalk

experience? or what a book or magazine said? just asking because i speak from years experience and with many chats with rick and danny at anderson ford. 24's just stink.

[BHAM]

Originally Posted by foxrodsinc

experience? or what a book or magazine said? just asking because i speak from years experience and with many chats with rick and danny at anderson ford. 24's just stink.

Experience. You are honestly saying you think the op setup justifies 30's?


Sent from my iPhone using Tapatalk

[foxrodsinc]

yes honestly. we do 30's on all hci cars here. just did a 306 ported iron gt40's b cam,longtubes anderson power pipe abaco 97mm 75mm tb. 30's. car right now is untuned and drives like stock. if i remember correctly 24's have 5 small holes and the 30's have one spray nozzle. it does atomize better. to get the 24's to work right the fuel pressure needs to be cranked too high.

[foxrodsinc]

i think this is like many of the common threads on this site like too big tb's and meters on small ci engines. gotta get past the old school mentallity

[BHAM]

19lb/hr injectors @ 39 psi can feed a n/a mustang producing 300 hp, @ 60 psi it can support a n/a or moderately boosted mustang producing 330 hp. Other combinations of fuel pressure and volume will allow 19lb/hr injectors to work well in engines producing as much as 350 hp. Specific combinations of 5 litre engine equipment and tuning specs have also been known tosupport 400 hp, but the injectors are being worked exceptionally hard at this output level. The 19 will offer improved atomazation over 24's, likewise the 24's will offer better atomazation over the 30's.
@ 39 psi 24lb/hr injectors can feed a n/a mustang producing aproximatley 400 hp.
This young mans setup will NOT produce this much hp n/a so how could you recommend 30's? That's like putting a holley 850 dp on a stock like application, sure it will run........... But fast it won't.


Sent from my iPhone using Tapatalk

[BHAM]

Originally Posted by foxrodsinc

yes honestly. we do 30's on all hci cars here. just did a 306 ported iron gt40's b cam,longtubes anderson power pipe abaco 97mm 75mm tb. 30's. car right now is untuned and drives like stock. if i remember correctly 24's have 5 small holes and the 30's have one spray nozzle. it does atomize better. to get the 24's to work right the fuel pressure needs to be cranked too high.

I'm sure it runs, but not near as good as it would with 24's. And I hope you didn't recommend that combo. It is grossly mismatched

Sent from my iPhone using Tapatalk

[BHAM]

Originally Posted by foxrodsinc

yes honestly. we do 30's on all hci cars here. just did a 306 ported iron gt40's b cam,longtubes anderson power pipe abaco 97mm 75mm tb. 30's. car right now is untuned and drives like stock. if i remember correctly 24's have 5 small holes and the 30's have one spray nozzle. it does atomize better. to get the 24's to work right the fuel pressure needs to be cranked too high.

You aren't remembering correctly, most 24's are a pintle style nozzle. Although the 4 hole revision actually does help with atomazation . Like on the newer pink top 19lb/hr injectors

Sent from my iPhone using Tapatalk

[nealysa]

Casillas5.0, just get the 30lb injectors get a tune and enjoy your great running car. 30lb injectors are not too big for your combination. My old combo H/C/I with 24's was about maxed out at just over 310whp. Every car is different, but you will be just fine with 30's and a good tune.

[Dart347GT]

i would just get the 30's, and you will have room to grow. I dont know why anyone would make such a small jump on the injectors, unless it was a junk yard score.

When I put my supercharger on a basic bolt on stock long block many years ago I knew it was gettng tuned, so I bought 42's right off the bat. Was it more than what i needed yes, but the tuner had it tuned quite well. Then as I increased the power it was nothing but a quick touch up tune.

Now those same injectors are on my 347, and will be fine till it sees boost somewhere in the distant future.

If the car is being tuned by a pro, then just get the 30's.

Oh, and before someone says, ( well why not just get 60's then ) everything within reason of course.

[Joel5.0]

Originally Posted by WHITEMACH

ford did overkill 93-95 cobras with the 24s.....put them in my car lost 14rwhp,,,took them right out to

The single component rationale.... .... let me see, you installed 24#'ers and lost RWHP w/out changing anything else..... mmmmm .... how could that be?

[slow87GT]

Joel which trucks came with 24's?

it would be nice to know for all the junkyard dogs to source them

I thought the 460's did, but I honestly cant remember anymore

[BHAM]

Originally Posted by 2cammer97

24 lb injectors are plenty of injector for any stock shortblock 5.0 with H/C/I.

You can always get 30 lb injectors and have "room to grow" but I never really think it's wise to buy parts that do this. Build your car optimally for it's current setup. Even with your future changes 24 lb injectors would be fine.

Marcus

Marcus couldn't have said it any better.

What these guys are advising you to do is mis match you current combo in hopes that someday you change it to match what you are installing now (30's). Like I said it will run, but it's not going to run like it should with the correct part.

If that is the case you might as well stick a huge f-ing cam in it too, since someday you will be installing big heads and intake + maybe a supercharger. Again it WILL run, but don't get butthurt a stock mustang runs circles around you.