EFI on a 351C 4V

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Use a CHI intake. They already have the injector bungs cast in and they are top notch quality. You could also use tongues in the ports to get the volumes down a little.

The HO 5.0 firing order is correct for the 351C, so you're good there (as already stated).

I don't think the 19lb injectors will be big enough, though! And you'll need a custom tune.
 
My EFI

Attached is my intake pic. 80's Roush motorsport high rise vs a torker ( on right ). This is a height comparison, as the Roush is quite a bit higher with its air gap configuration. It also has raised ( and narrower ) runners. Welded in injector bungs, 42 lbs, 80mm, mass air, EPEC computer, 351W TFI dist ( modified shaft), etc.
Hood clearance was the only issue. My solution was to shorten the CHI power elbow, by 1", and reweld it. I'm pretty happy with the set up. Nevertheless, a true gearhead is never really done with a project right?
Recently removed the cast iron 4V heads, going to aluminums!!
My advice, if you are going to do this then do your homework, figure how much your budget ( time and money ) is, then Double it!
 

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If you weld injector bungs into your intake, why can you not use a old (dry) carb for a throttle and plum in a iac valve in the back of the intake. Carb does not even have to be good.
 
If you weld injector bungs into your intake, why can you not use a old (dry) carb for a throttle and plum in a iac valve in the back of the intake. Carb does not even have to be good.

Well, you would also have to find a way to rig up a TPS.
If you use a carb, would you need an IAC?
That is the solenoid that allows air in to regulate idle, correct?
If you use a carb, it has air bleeds and slots, sometimes even holes in the throttle plates, to allow idle air into the engine.
 
Well, you would also have to find a way to rig up a TPS.
If you use a carb, would you need an IAC?
That is the solenoid that allows air in to regulate idle, correct?
If you use a carb, it has air bleeds and slots, sometimes even holes in the throttle plates, to allow idle air into the engine.

Yes, but you want to be able to control the amount of air than enters. When the engine is cold and 1st started up, it needs alot more air to idle.

Modifying a carb is a good idea, it's been done a few times and there are lots of writeups out there on how to do it. Here's a good one: http://www.mez.co.uk/ms2.html

Or, for $75 why not buy a brand new throttle body? http://www.auto-nomics.com/cgi-bin/showresults?a=detail&part=10850-002-D
 
I already have the original TB and mass air meter. Is there an advantage to converting a carb over using these? (Interesting challenge, though!)

What size injectors would you guys recommend (I agree that the 19# are likely too small)?

You guys are all giving great information! I really appreciate it!
 
I already have the original TB and mass air meter. Is there an advantage to converting a carb over using these? (Interesting challenge, though!)

What size injectors would you guys recommend (I agree that the 19# are likely too small)?

You guys are all giving great information! I really appreciate it!

If everyone thinks the 19# are too small. Do you think the stock TB and MAF are big enough?

Maybe you want a larger aftermarket MAF calibrated for the larger injectors. You might want a larger TB too.

I wonder how much of the stock EFI system that you have on hand will actually be used in the end.
 
I run 42 Lb injectors, 90mm throttle body & MAF. You can certainly run less injector, and less throttle. It depends on the cam, compression ratio, 4V vs 2V heads, ect. ect. I think 24's are O.K.
I run an EPEC with no IAC. starts and idles O.K., I may add a cold run dashpot, or solenoid.