Hi I'm wondering what would be the best cam upgrade for a 99 F150 with a NPI 4.6. Engine is stock except for the gotts mod. I have looked at cams at Comp Cams and at Modular Head Shop. Just wondering if any of you have used any of the cams they offer.
Thanks.

 

Whats your goal with the truck? Street scene, off road? The more information you give us the better we as a community can help. Also welcome to the site!

 

What kind of power? Horse, torque, top end power, low end?

 

You would benefit more from getting PI heads probably than you would the cams alone.

 

I have heard that stock PI cams will fit and give some improvement however I can not speak for the validity of that claim. Hopefully someone else will chime in and speak of the improvements and if they fit.

 

PI head swaps are common, plus you get around 25-30 more horses and COP ignition.

 

I've heard the 25 - 30 hp number, too.
The COP ignition is another matter:

http://www.sn95mustangs.com/index.ph...lug-Conversion

 

I don't really have a goal for the truck, I would just like some more power towing and for passing on he interstate. I'm leery about the PI head swap because of the compression increase and having to use premium fuel. I have read that just getting my heads ported would be more effective for the money than swapping on PI heads. I would like to keep the same 3.55 gears in my truck as well because I do a lot of highway driving. I use the truck to tow my 86 Omni GLH to the track and it would be nice having some more grunt for going up hills and trying to keep up with my brother who has an 11 5.0 F150. I emailed Modular Head Shop and they said their Torquer cams would give me about 20-25 hp and 40-45 lb ft, which would be a nice increase along with going to an efan set up. I have already done the gotts mod and love the extra sound the engine makes and the increase in power and mileage is nice too.

 

So would installing the Torquer cams increase or decrease fuel economy or stay the same? Also could ya still use regular 87 gas?

 

You are gonna have a long road to make a 4.6 keep up with the new 5.0. I say just SC it and be done lol.

 

You don't have to use premium fuel to run PI heads. My truck came with them and runs on 87 octane.

 

PI heads are just different intake ports... You can get them off the 99+ 5.4 and 4.6. There will be some nip heads floating around yet too.

 

I would swap in a V10 before putting a supercharger on it.

I know it would take a lot to keep up with the new 5.0, I just want to have it work less at doing it.

If I swapped PI heads on my NPI block I would have to run premium because of the bump in compression. The PI heads have a smaller combustion chamber than the NPI heads. PI pistons are dished while NPI pistons are flat top.

 

If you look around, you'll find lots of info on people who have swapped PI heads on NPI trucks with great results, and no need to use premium.

 

It doesn't detonate with 87 and the 10.0-10.5 compression ratio that the PI heads create on an NPI block?