I got stock motor w/ rouscharger@10psi, pacesetter long tubes, stock 3.55's, 33" tire. Tune from JDM, shift points are not anything crazy. Thinking rear gears before cams.

 

You can look into VSR cams from comp. Stage 1 or two would probably. I would talk to jdm see what they recommend. Shifting at 5000rpm limits cam power potential. Check out the brenspeed detroit rockers. I know they made 27rwhp on a saleen truck

 

Bingo! 4.11 Yukons will be like bolting the blower on all over again(slight exaggeration) I to had 3.55 gears but 32" tires. 4.11's were the second best thing I ever did to the truck. Less spin on launch, truck feels like it's ready to go at any speed, super responsive.

 

Here's a chart showing gear ratios and rpms. This chart is based on a 1:1 ratio which is 3rd gear in our trucks. Putting 33" tires on 3.55 gears verses the 30" tires you had stock is like having a 3.21 rear gear. Imagine that Now you know why you aren't perfectly happy with the trucks performance.
You would need a 3.91 gear with those 33's just to get back to where the truck was stock. 4.11's would put you where you want to be.

Just a quick note I run 31.5" tires now on the street and 28" tires at the strip. A quick look on the chart and you can see I'm getting the best of both worlds on the street (Performance & MPG's) and best performance at the track.

 

Gears is my next upgrade. I put 4.10s in my ranger and it made a huge difference too.

Www.diffsonly.com

Buy a bearing kit too

 

Damn still with the arguing. When will it stop??? For what it's worth Irons1n didn't post anything inaccurate about the cams so I don't get the arguing. I don't think anyone has argued the validity of blower cams over N/A cams. Irons1n even posted a helpful pic showing lobe separation which supports what Crash has been saying about the differences and scavenging. Lastly the guys in this thread considering cams are not running 4.6 Prochaged trucks through a 5 speed and 8.8 rear end. So this comparison is hardly beneficial. No offense just saying. These guys weigh 5500-6000lbs, turning a slush box trans rated at 750ftlb not 500, and a 9.75 rear. Huge difference there. Should I even mention the difference in arel-push between a 98-03 truck verses the 04+ trucks.

To anyone considering cams...sticking a set of cams in the stock 5.4 that have the potential to move the rpm band up 1000 rpm would not be good. You can't shift these trucks at 6000 with boost unless you want windows in the block. The rods won't take it. 5500 is about it on 8-10psi. The stock converter stalls pretty high at 2800rpm so everyone here who has an 04-08 5.4 should consider this. You have pretty high stall right from the factory. Looking at gains on a 4.6 on a set of cams is fine but not the same as your 5.4. Why? A 4.6 has 50 less cubic inches then the 5.4. If 4.6 can pick up 11hp from a set of cams breathing a little easier then an engine displacing 50 more cubic inches will benefit even more from the access to more air. Especially considering they are breathing through the same heads and the 5.4 is trying to displace more air. Hope that makes sense. I would encourage anyone considering cams to think about the cost, talk with a reputable tuner such as JDM. They have installed them, tuned them, raced them, driven them the street, and can help you make the best investment for your money.

 

God not this thread too. Sorry folks just ignore his anger towards me hes an idiot and knows not what he does.

Anyway, twinscrewed is correct.

 

Well I had a nice reply but chrome ate it

Right now I am targeting 4.11's and a torsen diff. Not sure if I am going to do anything different in the front or not. It is a 4x4 truck and has open diff. Just for labor I was quoted at I think 2k?

I can feel the truck surge when going up hills and the cruise is set, which I do not like. Gears will fix this.

On the cams, the detroit rockers look the way to go, they do not require springs, which is nice. I do not want to take the heads off right now.

Been also watching twinskrewd and his built motor tread. I won't lie, I have been looking at built bottom ends and doing some window shopping. I need to get the gears and exhaust done first. and hoping to do these before the snow flies. I also have a mess of home improvement projects going on. The wife is not pleased with the truck. When we bought it the agreement was I would do nothing to it. That lasted 2 or 3 months.

 

If you regear the rear you NEED to do the front. Never only do one. Also, is your rear factory limited slip? Detroit TruTrac is suppose to be a nice setup if not. AllCarFan had the detroit rockers in his S331 like I previously said. His review of the cams.

http://www.brenspeed.com/detroit3vsc.html
All the guys report about the same 25-30RWHP gain at 5500-5700RPM. Not bad for some sound and a fairly easy mod to do.

 

Yes, I am aware I need to do gears at both ends.

So on a boosted 5.4 in f150, our shift limit is 5500 from what I gather due to craptastic rods. If rods/pistons are up to snuff, pretty much limit of motor then, correct?

 

Yea in theory you can spin a 5.4 over 7 grand all day. Gt500s with higher flow heads have no issue. Its all in what you do with the heads/cams etc

 

Correct. You can push for more but it's risky at best and not worth the possible tenth of a second you may gain. Thats my opinion of course. A motor for another tenth is a bad deal.
Anyway your next limiting factor is the torque converter which doesn't like more than 6000 rpms followed by the tailshaft bearing which just needs the additional line mod. I believe Fatherford has it. Maybe he can share a pic.

Circle D can set you up with a solid converter that will take the abuse for less than $1000.00

 

The more RPMs you spin you will loose bottom end. You then have to use gearing and a stall converter to get straight into the powerband off idle. If you plan to keep this on the street mainly, I would go probably 6000-6500 rpm. These stroke motors dont need RPM for power but its all in how you build it.

 

What's a line mod?

Basically keep rpms under 5500, add more gear, then go for cams. Seems simple.

Edit: Googled line mod, found this: http://www.teamjdm.com/ford-svt-ligh...ine-mod-valve/

So it looks like something with a valve body. I thought everything on these trans was controlled via electronics?

 

Its actually the addition of a hydraulic line from one of the exterior ports on the trans a d running ot to the tail shaft. Of course a fitting must be drilled and tapped in the tailshaft.

Heres some mods you can do to your trans to really wake it up and make it last.
http://www.tccoa.com/articles/tranny...on/index.shtml