What is the weak link in these motors. I am thinking of supercharging and would like to know what a safe power level is?

I will ask more questions if this thread is answered.

Thanks,
Greg

 

Max it out at 425HP to the wheels. Anything beyond that and you need to beef up the bottom end.

 

Super. Thank you so much Ken.

 

Greg,

Question... your truck is 4x4 with stock wheel size?

The reason I asked is if you're running a heavier drive train config (for instance, I have 20 inch wheels) I'd give a little more margin, say 410 at the wheels because there are more parasitic drive train losses.

Someone may chime in an say you can put out more than 425HP, which is true, but I remember you stating in another thread as your Cobra experience you want long term driveability? 425HP should give it long life, provided its done right. For an intercooled blower config, stick to 8lbs or less boost. With a good tune, good cooling and headers you'll be right at (or a little below) 425HP.

 

Yes, 4x4, FX4 with the 18" wheels. I think 410 is perfect, I am thinking 400 at the ground would be nice.

How does the transmission in my pickup hold up to power.

I see you mention headers, these are always controversial it seems, you think they are necessary. Is this to decrease heat (help exhaust get out) or for performance gains?

I definitely understand that people will say you can get more, and you are right, I don't want to go overboard, this is still a new truck and I don't want to take away from the drive ability.

Also, another question that is boggling me, is really that good to be launching in 4 wheel drive at the track and on the street? Are transfer cases holding up to that? And what about the high speeds, is that good for them?

I am definitey thinking inter cooled blower, and the 8-10 psi range, whatever will give me the power we discussed. Headers if needed can be done. And what ever supporting mods obviously, wh/ is what I don't know I need at this point.

 

With headers don't waste your time with shorties on a blown F-150. Get long tubes with high flow cats. With a blower they are good for about 20-25. Expensive horsepower. It will also require lifting the block up a bit to get them in (its why I haven't done this to my setup yet). Its for performance, not for heat (though heat will end up robbing performance too). Also, there's the issue headers are notorious for --- leaking. Something I'm not willing to deal with just yet.

I launch in 4x4 now and then. The guys in the Powerstrokes do as well. The key, IMHO, is to throw it out of 4x4 almost immediately after launch. The 4x4 is for launch only, so you can floor it and get all power to the ground without wheel slip. Don't let it shift with all that power in 4x4. I don't recommend doing it all the time.
10 psi is really pushing it with these 5.4 3v engines. Roush and most other others use 6-7 psi. You can push it to about 8-8.5 lbs. Anything higher and you're flirting with disaster. Don't worry though, 8lbs is plenty on the 3v (with that and a few other things you'll easily have 410 at the wheels).

I've run GMS coils on my truck and they help (slightly) on the top end with power ripple, but to be frank I've had too many reliability issues with them and the gains aren't worth the headaches. I'm going back to stock coils this weekend. If you go above 6lbs boost gap the plugs to 40 or less with stock coils.

I've taken out the factory fans and I'm running electric fans. Nice little pickup there --- have some good confirmed gains on the dyno.

Go to Level 10 if you build the tranny. They did the hardware in mine and I'm giving them my tranny calibration changes as soon as I get it perfect (its a trick to get a 10.5 inch lockup in the tranny to lock as smoothly as the smaller stock disc).

 

Great info, thanks.

I feel the same way about headers, wasn't looking forward to the messy install and expensive price tag. I may do electric fans in the near future as preparation, I love the idea and have read a lot about them when looking at the F150.

So for some suggestion, what can I do now in preparation for the S/C. Would you recommend rebuilding the tranny now to handle it or waiting until it starts to go, or will it go at those power level, properly tuned of course.

I do have a cat back exhaust now (super flow 44 (2.5" in 2.25" dual outlet)). Would you say I am set there?

I would love to start buying plugs and injectors but it appears most kits come with this stuff. And I haven't seen pricing advertised minus these things. It appears at the boost levels we are talking (6-8psi) the stock fuel system is good, is that correct? It looks to me as if the 10 psi jump is where MAF and injector updates are required, am I correct in that?

You mention level 10, what does that mean? Where can I inquire more about this and what is done?

Thanks again Ken,

Greg

 

Andrew, for some reason I can't see your post.

 

I can see it

 

Greg, I have Level 10's info. They are the one's who built my trans. Give me a shout.

 

Thanks Wes, I looked them up, I am going to talk to you more about them tomorrow.

 

What about the driveshaft, another weak link? Or is it OK?

 

Bringing this back up!

Has anyone used the MAF.ia from Diablo when needing a larger MAF sensor? I used on on my Cobra and it worked fine. I know in the Cobra world a lot of time replacing the MAF with a larger MAF sensor housing affected the driveability, so using the MAF.ia (or similar MAF xtender) you could keep the stock idle qualities.

Thanks,
Greg

 

how do you increase boost on your roush supercharger

 

Different lower pulley. Haven't looked for an upper but I can't imagine they are not available.