Cheap 4.6l Throttle Body Upgrade

[TeamCaffeineGT]

Hey all! I posted this in my 5.4 DOHC Swap thread, but thought I would make a new thread for it as well as it might be overlooked.

As I was walking through the salvage yard the other day looking for an idler pulley for a friend's Focus, I stopped and looked under the hood of a 5.4 F150. I thought "hmmmm....that throttle body looks bigger than the stock 4.6 Mustang unit!" Sure enough, I got it home and compared the two and it was considerably larger! Research that I have found shows the stock 4.6 unit is 65mm and the F150 unit is 75mm. They use the same bolt holes and everything!

I had to reuse the 4.6 throttle body blade shaft as the F150 shaft has the cable pulls on the opposite side of the axis. This required slight modification to the shaft as needed to slide the 75mm blade into the shaft made for the 65mm blade. I also had to drill a small hole in the throttle blade to match the 4.6 setup as the F150 unit uses a bypass built into the TB casting. From my understanding this is for idle improvement as the IAC tends to surge without it.

Not a bad upgrade for 20 bucks!

 

[Three50won]

Hmm, good find!!

 

[Mattstang04]

Nice. Can't beat the price.

 

[flstang65]

Veeeeeeeeery Iiiiiiinteresting...

 

[1987stangman]

Junkyard HP rocks. I'm all for it.

 

[TeamCaffeineGT]

Junkyard HP rocks. I'm all for it.

Right!? I mean 20 bucks versus 200+!? I know that junk yard parts aren't as refined as some of the nice aftermarket offerings, but HP at a 90% savings!? That's what I'm about!

 

[trombonedemon]

 

[Noobz347]

I love it when someone beats me to this.

 

[Gearbanger 101]

What year engine did the throttle body come off of. The 5.4L got several changes over the years. Have you actually got the car running with the new blade? Hate to see someone steered in the wrong direction over incomplete info.

 

[1987stangman]

Back when I was into the Fox Mustangs if a buddy got a stock one (hard to come by these days) we could go to the junkyards around here in Jacksonville, Florida where there are a bunch of them and grab a set of GT40 heads and the upper and lower intake from a early V8 Explorer and run good numbers at the track on a stock tune. There were a ton of choices for bigger TB's and Mass air meters as well as 24# injectors were (and still are) easy to come by although using bigger injectors and meter required a tune it was still bargain power. We also borrowed the brakes off the New Edge Mustangs and used certain years cars and trucks 8.8 axles for 5bigger brakes and five lug swaps. Those were the good old days. I regret selling that car!!

 

[TeamCaffeineGT]

For those of you who only learned how to read from picture books.

The F150 TB measures roughly 2 7/8 inches which is roughly 73mm. The factory 4.6 Mustang TB measures 2 5/8 inches which is 66mm. The stock mustang plenum also measures 2 7/8 inches.

Note the differences in the shaft pulley configuration, primarily the idle stop screw. The part number for the F150 TB is F65E-CA, however this must be an obsolete part number as it didn't come up in the ford parts database on fordparts.com. a Google search indicated it was off a 97 F150.

This throttle body upgrade bolts directly to the factory plenum and has the added benefit of an idle control screw. This unit is currently bolted to my coyote intake on top of the 5.4 DOHC Navi sitting between the strut towers. This combination yielded 271hp and 317ft/lbs at the tires on the dyno.

 

[TeamCaffeineGT]

I don't mean to break etiquette and bump my own thread, but I thought I would add a quick note about the idle adjustment setup on this TB. I decided to do an IAC delete on my 5.4 DOHC. I was experiencing a bit of idle surge and decided I wanted a more consistent idle. The TB has an allen head screw on it for idle adjustment, so I decided to see if could be adjusted enough to maintain a good idle with my heavy breathing 5.4 4v. Sure enough, with the IAC removed and everything capped off I was able to adjust the TB to get a smooth perfect idle. I have plenty of adjustment to slow the idle down enough to kill the engine, all the way up to around 1200 rpm.