im looking at a CAI w/ a 75mm TB does anyone have advice on bigger TBs and what kinda gains will i see with the combo all the site posts is CAI gains

1997-03 F-150/ Expedition BBK 75mm Throttle Body & Cold Air Kit

 

That's a lot of money! You would gain more power with efans.

 

That's a waste of money, do the gotts mod for the intake. It'll cost like 10 bucks at home depot for the stuff and a couple hours of work but pretty much the same gains as a cai. And from what I've heard tb spacers aren't really worth it. E-fans would definitely be a better way to spend your money.

 

Total waste. To see any improvement, you would need a new tune. That would be another $500 or so. Just get a programmer and custom tunes. Single best mod you can do.

 

To put it another way, the motor can't use any more air in stock form unless your near 5000 rpm.
The intake manifold is restricted in airflow in lue of 'tuned' length fast air flow for low end torque.
Exhaust is also restricted.
Cams are short duration.
Motor is a small displacement.
Truck is heavey.
As an example, even a 5 liter motor at 5000 rpm will only draw about 500 cfm from it's basic displacement and even less through the total of all intake restrictions such as the intake tracts, head ports, intake valve restrictions etc.
When any extra flow capacity beyond what can be injested is available, it cannot be used.
This even translates to air intakes mods.
Intake filter, stock, is sourced to flow more than the motor can use at any given time so there is some life to it before it has to be replaced due to dirt restriction. Same filter is used on the 4.6 and 5.4 L motors.
.
What your proposeing is a waist and will lose more low end torque.
Better to get a Mustang.
Good luck.

 

will i did the gots mod and it didnt do anything unless im doin it wrong i read the write up but how far am i supposed to go in and this is not a spacer I HATE SPACERS this is a bigger TB

 

doesnt matter. read the post above yours. a custom tune would be a better buy

 

Like I said, makeing more air available means very little if the motor won't take it in.
In the example I gave above for the 5L motor; now compair to the 4.6 at 263 cu/in is even smaller yet.
Spacers add so little to the intake tract length that you cannot feel a torque performance difference. But they can make some noise deluding you into thinking you feel some improvement.
It takes at least 10hp to be able to feel a seat of the pants difference.
No simple mods will offer that much improvement.
The 4.6L does not begin to really enter into it's good torque band curve until about 2000 rpm where it peaks at just over 3200 rpm.
This is partly the cam timing and the intake tract length working togather making it 'come on' like that at 2000.
In OD cruise your lucky to see much more than 1500 rpm at 60 mph where the torque is quite low and not much throttle response.
Good luck.

 

okay ill go with a custom tune does anyone have a site that sells customs for my truck

 

Vmp does good work. 3 custom tunes and tuner 400$ out the door. 93 octane performance made a BIG difference for me.

 

If you do the CAI the the exhaust would have to be there to and you would move all the TQ and HP higher in the RPM range. The 4.6 (281 CID) is small for our heavy trucks. A basic programmer E-fans and underdrive pulleys would be money better spent if you don't have all the right mods done at the same time with a custom tune it will hurt you rather then help.

 

I got a programmer and vmp tunes and I can't complain one bit. Really woke my 4.6 up

 

Im running a CAI Magnaflow exhaust and a diablo sport preditor on my 4.6 and im happy. I put on a bbk 75mm tb and it did nothing at all waste of 300 bucks obx long tubes and high flow cats are my next performance investment. Do under drives really give you more? Ive always heard waste of money. Now im curious.

 

Under drive pulley:
They tend to reduce the drive losses the motor sees that are equivelent to about 8hp +/-.
The other result is you loose alternator, A/C and possibly power steering performance at idle and low engine RPM such that it could be a hassle for some owners, at times.

 

Power hungry performance....edge CS/CTS programmer with custom tunes....



Vmptuning, 5startuning, Troyer performance.....sct SF3 along with custom tunes....



Diablo predator or trinity along with custom tunes....