a few important questions?

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background info. 96' f-150 , 300 I-6, .040 over, full msd ignition , 9.8:1 compression, full Crane valvetrain, including truck power cam, gold race roller rockers, 80 mm pro-m mass air sensor, 17# injectors, clifford headers, true dual exhaust( exit out side), dynomax super turbo muffler, and some other little stuff....


1. Is the performance effect worth the money to switch over to a dual electric fan setup?

2. I heard a rumor about putting a 460 throttle body on a 4.9... is this true? and does it bolt right up? and of course, is it worth it.

3. now that my motor is bored .040 over, what would my calculated displacement be?

4. When i first start up my motor what oil should i be breaking it in with ( synthetic or what?) After the motor is broken in, I was planning on running full synthetic, is that the best way to go to keep it running it's best?

5.Because i have to have my exhaust redone, I am going to have to drive to the muffler place with open headers and some long pipes. What i want to know is, Am i even going to be able to do it with out my secondary air system hooked up and without my 3rd O2 sensor installed? Or am i going to have to trailer it there?

thanx
Chris
 
1) I've read numbers on the order of 10 HPgain by going to electrics. Be sure your alternator is big enough. Personally, I've got some reliability questions about electrics.

2) larger t/bs only work if you've ported out the head and intake to give you the increased flow path all the way through. Don't know about a 460 t/b, one from a 300 bolts up but the ports don't match the intake.

3) 306.12 CID

4) not sure it matters. I break in on dino and switch to synth at 1000 mi. Some peolpe run synth from the start.

5) It'll run but it will throw error codes.

Are you sure those injectors are big enough? They're rated for 17# at what PSI? It makes all the difference in the world. The stock injectors are 17# @ 58 PSI. Are yours rated at 58 or at 39? If they're rated at 58, you're going to get very little gain out of all those mods.
 
Thanx for the quick info strangeranger. My injectors arerated for 17#'s at 44.1 psi. You obviously seem to know way more about the whole engineering side of it than anyone else, so what's your take on it, should i be running an adj pressure reg. valve or bigger injectors or something.
I was also a little curious to know if you are by chance like an engineer for ford or something, because you really seem to know what you are talking about.

thanx
chris
 
I'm an engineer but not at Ford. I design polyurethane process equipment, so there's not a whole lot of synergy. I'm assuming that you intend to run the stck regulator if possible? That should put you somewhere around 58 PSI. Your injectors will actually put out:

(58/44)^0.5 x 17 = 19.5 #

That should be enough fuel for at least

(19.5 x 6) x 1/0.50 x 0.80 = 187 HP

and no more than

(19.5 x 6) x 1/0.47 x 0.90 = 224 HP

You're not going to find an adjustable regulator that's going to run at a higher pressure to give you more thruput. Also on a 96 the fuel rails are different from the earlier years and an adjustable regulator may not be possible. I couldn't figure out a way to do it, although I didn't try real hard. You may want to just get slightly larger injectors. The stck 19# Ford units are good for about 23# when run at 300 pressures and will permit at least 220 HP and may allow as much as 264. you will hve to have your mass-air meter re-calbrated to match.
 
So are you saying that no matter what else i have done to the motor or anything, there is absolutly no way i will be able to break 224 hp?
 
my bad....
or is what you are saying that your calculations are accurate for a totally stock motor?

Me and everyone else that i have spoken to about this find it kind of hard to belive that the max hp i will be able to pull is only in the 220's, seeing as how you could take a stock mustang with 19 lb injectors and be able to achieve anywheres up to like 400 -450 hp?
 
A 5.0 with 19# injectors tops out at an absolute max of around:

(19 x 8) x 1/0.47 x 0.9 = 291 HP

Fuel injectors do not produce HP, theysimply provide enough fuel for the mechanical mods to work. If the 19s aren't big enough there's always 24s.
 
so lets just say, for the sake of argument, I do pull only 224 hp, and i am not satisfied, so i decide what the hell, why don't i just put a blower on it, or nitrous, are you telling me, i am not going to gain even 1 more hp without larger injectors?

I'm not trying to sound like a dick, but what you are telling me just doesn't sound right to me.
 
8)

I am not worried about going to electric.

My 86 LX Mustang with a/c and air came factory stockwith an electric fan and no engine driven fan. It still was working fine 10 years later. Had to replace the fan relay once.

Just make sure it is a well known and reputable electric fan company.

And yes 19lb/hr injectors will NOT provide enough fuel for turbo or nitrous on a 5.0L motor. My friend who had a Vortech 93 GT was running 36lb/hr injectors, larger MAF and TB, and a 190lph in tank fuel pump.
 
It all comes down to Brake Specific Fuel Consumption or BSFC. For a normally aspirated gasoline engine running at or near a stochiometric ratio, that's going to be about 0.50 lbs per HP per hour at the HP peak. For really efficient engines this can improve to somewhere around 0.47, but you cannot count on that. When you add a blower, turbo or nitrous, the BSFC increases (i. e. it takes more to produce each HP to around 0.55 lbs. per HP per hour.

Fuel injection systems do not add HP, they simply supply fuel to the engine. If the engine is built to produce 225 HP you need injectors big enough to supply that amount of fuel. If you build a 300 HP engine you're going to need bigger injectors.

Injectors are sized to run at 80% of maximum rating; in a pinch you can bump that to 90% but no more.

Now the rest of the bad news. Your stock fuel pump will put out 95 litres/hour at 58 PSI. At 6 lbs/gallon for gasoline and 3.785 litres/gallon thats about 150 lbs of fuel. You need to keep about a 10% reserve capacity in the fuel pump sizing as well, so call it 135 lbs. That's enough for about 270 HP. Go above that and you need to upsize the pump.
 
Howdy Ibeam,
In order to make more power, we have to burn more fuel. This fuel needs to be in a reasonable ratio to the air that it is mixed with. If you modify an engine to flow more air, you have to increase the fuel volume in proportion to the airflow. The only ways to increase liquid flow through a pipe is to either increase pressure or increase pipe diameter, and a fuel injector nozzle is really just a small pipe with some special gizmos added. I'm with Strangeranger on this one, he really isn't pulling your leg. Methinks a stock Mustang that puts out 400+ hp was tested on a dyno that was rated in Shetland ponies :wink:
Lazy JW
 
well, i guess that convinces me, i am gonna have to buy bigger injectors. So what is the largest injector i could run, without needing to upgrade my ecu or my fuel pump?
 
by the way, this is the first motor i have ever built, and i am kinda new to the whole performance deal, so bear with me on all the stupid questions. thanx

Chris
 
The stock pump, with a 10% reserve capacity, puts out about 135#/hr. On a 6 cyl that will support injectors which flow:

135/6 = 22.5 puonds per hour per injector.

That's pretty much the output rate of the Ford 19# injectors when run at the 300's pressure of 58 PSI. That will provide enough fuel to support an engine which produces somewhere in the range of 220-264 HP. This is an increase of 50% or more over stock and represents a very realistic goal for a street driven 300. FWIW The Frenchtown Flyer has a matched set of 19# units for sale in the classifieds. If you can't talk the dealer who sold you the 17s into a trade, you may want to talk to him.

To implement the 19# injectors you need to have your mass-air meter recalibrated. The manufacturer will need to know nominal injector size and pressure drop, which is 55-58 PSI. That will control your fuel flow at steady state but you still may experience some drivability problems. This is because 14# and 19# injectors have slightly different response times so it may idle a bit rough or not pull smoothly at part throttle. If that is the case you'll need to either find a dyno-tuner who can play with the settings in your PCM (ECU is an obsolete term) or get an add-on chip. I cannot make a recommendation as to a chip maker, they all promise way too much in terms of gains on a stock engine to have much credibility in my book. I suspect that once you get past the advertising BS and talk about application-specific custom chips they really do offer some gains.
 
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