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I am building a 354 motor in a 92 coupe. It will have 10:1 C/R with a 235/242 Dur @.050 and around .550 lift. What size injectors, mass air, and throttle body will I need to use. I have some 24lb injectors right now. Will those work or do I need bigger ones. Any help would be great. Thanks in advance.
 

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If you have heads that will support the flow that would match up to the high rpm cam you have selected, you will probably need 36 lb. injectors. You might get by with 30 lb. and higher than stock fuel pressure.

Again assuming the balance of your combo is intended to support the high rpm capability of your cam, you'll probably need a minimum of 80 mm mass air and 75 mm throttle body.

Is your cam a hydraulic roller? You're going to need a very well set-up valve train to handle the rpm required for a 354 cube motor to utilize that much valve timing.

Steve A.
 

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Thanks for the input. I guess I should start over and ask what cam and heads should I use with a 354 cid motor and then base the induction on those choices. It is driven everyday and some strip use. So It needs to be reliable and driveable. I don't plan on twisting it over 5500 rpm. But I want a cam that makes good mid-range power becase it will already have a lot of torque with a 3.470 stroke. If someone could point me in the right direction, I only want to spend the money once on the right combo. Thanks
 

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turbocharged87 said:
Thanks for the input. I guess I should start over and ask what cam and heads should I use with a 354 cid motor and then base the induction on those choices. It is driven everyday and some strip use. So It needs to be reliable and driveable. I don't plan on twisting it over 5500 rpm. But I want a cam that makes good mid-range power becase it will already have a lot of torque with a 3.470 stroke. If someone could point me in the right direction, I only want to spend the money once on the right combo. Thanks
Asking for advice on a couple of engine components without stating the rest of the combo or the intended application is as misguided as me or anyone else offering advice without knowing that information. Now, we're both headed in the right direction!

You are going to get many opinions on heads/cam; here's mine:

If you're going for a good performance upgrade at the lowest possible cost, I'd recommend TFS TW heads. Good performance and decent quality at comparitively low cost.

If you want outstanding performance for your application and excellent quality, I'd recommend AFR 185 heads. For ~$300 more than the TW, you get fully CNC ported intake ports, exhaust ports, and combusion chambers. This is an outstanding value, and would be my personal choice.

With either head, get a custom cam from Ed Curtis, Buddy Rawls, or one of the other proven Ford experts. Talk with them prior to selecting any engine components so that the pistons/heads you choose deliver the optimum compression ratio, etc. etc. Ask for their advice on all the other induction/exhaust/gearing/etc. components, and LISTEN to them. The advice you'll receive makes the $100 or so extra you spend on the custom cam a bargain, and can easily prevent you from making mistakes that will cost hundreds more to fix later. This paragraph is the best, and strongest advice I can offer.

If you choose to cheat yourself out of that custom cam and low-cost professional advice, here's some "shadetree special" advice for free:

Hydraulic roller (convert if you have to) with intake timing in the 224-228* range @ .050". Especially with the great exhaust ports on the AFR, you should need little if any additional duration on the exhaust side. You can do around .525 - .550 lift for a daily driver, but make SURE you have the right springs to match your cam. Probably around 111-112 lobe separation angle. Use roller rockers, and make SURE your valve train geometry is right. If you don't know how to set up the geometry, get pro help; otherwise, you'll be burning oil from worn valve guides in short order.

80mm mass air, 75mm TB, 30 lb. injectors. Be careful on manifold selection. You don't want a short runner manifold on a 5500 rpm engine; you just want to be sure the runners' cross section will flow the necessary air. A mildly-ported Performer 5.0 might be dandy.

I'll get flamed for this, but I'd do 1-5/8" headers on a 354 inch street car with a 5500 rpm red line. 1-3/4" MIGHT outperform the smaller tubes above ~5000 rpm, but where do you operate you engine 90%+ of the time...1000-5000 rpm, or 5000-5500 rpm? I'd rather have that strong, "big-block" torque feel where I drive 90% of the time. Good luck with your project!

Steve A.
 

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Discussion Starter #5
Thanks for the advice. I nice to find people that are willing to help a guy out. Thank You
 

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amossm said:
I'll get flamed for this, but I'd do 1-5/8" headers on a 354 inch street car with a 5500 rpm red line. 1-3/4" MIGHT outperform the smaller tubes above ~5000 rpm, but where do you operate you engine 90%+ of the time...1000-5000 rpm, or 5000-5500 rpm? I'd rather have that strong, "big-block" torque feel where I drive 90% of the time. Good luck with your project!

Steve A.
To each his own, but I'm with you on maintaining an off-idle to 5,000-5,500 rpm power band for the STREET. I've got a car that will run low 12s N/A and low 11s on NOS and it really isn't that pleasurable to drive on the street.
 

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Most engines that get built to deliver high performance are designed to run somewhere in the higher end of the rpm scale. We tend to select cams, manifolds, etc. that deliver torque in the upper end of the range, because that's what produces the high, calculated horsepower value. This is exactly what's needed if you're building a drag strip terror. Also, we all tend to fall in the "horsepower trap"...too much is always just right. Well, right for what? Application is the key.

With the right components, a very formidable street engine can be built that makes its power from 1500 to 5000-5500 rpm (just ask the 4x4 crowd; they're good at it). Never be afraid to build a well-designed, optimized 5000-5500 rpm street engine. Done correctly, you'll love it. Any time, any place, any gear, throttle down means being shoved hard back in the seat. This kind of motor may be short on bragging rights, but long on [email protected] and gitting whenever you punch it on the street. Performance talks, BS walks. The fact that it will provide this terrific performance for 100K+ miles along with good fuel economy at cruise is just a bonus.

It's important to remember that torque is an actual measurement of force; it's power that you can feel in the seat of your pants. In any given gear, the acceleration delivered depends on the twisting force, or torque, of the motor as translated to the rear axle by the drivetrain. The particular rpm at which this force is created is immaterial to acceleration...even though the rpm determines the horsepower at any given torque level!

In other words, horsepower is not something you feel in the seat of your pants, believe it or not. It's merely a mathmatical calculation of torque multiplied by time. More horsepower simply means that the torque is delivered higher up in the rpm range. Now, horsepower is what you need in a drag race car, because it allows you to remain in a lower gear farther down the track, thereby increasing average axle torque on a run.

I posted on another forum a rather detailed explanation of how all this actually works, as well as how to choose shift points to optimize the torque produced by your particular motor and delivered by your drivetrain gearing. Rather than hogging up more cyberspace here, if you're interested it's at the top of the third page of this thread; my user name there is Amossm:

http://www.fordmuscle.com/phpBB/viewtopic.php?mode=viewtopic&topic=1036&forum=1&start=30

Steve A.
 
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