5.4 3v dyno sim with big comp cams <6000rpms

yeah, its ready.

i'm going to run it at the track wednesday. chasis dyno asap. my expectations are kinda dashed by the sims.

one of the guys i'm talking to on f-150online.com, who has added as many bolt ons as he can, is just barely getting 280 whp. ford has an opportunity to do something with these by adding just a little cam. i know ford is getting ripped by f-150 owners. they have lost business from this.

i'm going to retard the cams one tooth before dyno. those comp cams are advanced 15 degrees standard.

yeah exactly. with vct they are trying to build as much low end as possible, even with a huge cam. retarding it to -2.5 degrees maxxed the HP for <6500.

the 3v in a 5.4 simply won't pull past 6500 in a 5.4.

the runs done with the real 127305 cam made 425hp@6000 with ported heads and 1 5/8" shorty headers, short runner intake, etc. i haven't explored stepped headers. now that i have the 4v motor staring at me. it's difficult to continue fooling with the 3v. i should have waited. the 4v is a piece of cake to get 500. it takes 12:1 CR to get more. so really the power is there, but it falls short of the streetable/daily driver 500 NA criteria. i said it already, but it's an embarrasment to ford that they skimped on cams. add 10 degrees to both in/ex and they have a killer on their hands. i'll continue to try combos to try to stumble onto something better.

no i'm not retired, i just lie to my wife.


she thinks this stuff helps with gas mileage. no matter how many times i tell her the budget, she forgets and gets mad at me for buying more stuff.

she offered to let me get a new GT if i sell this one and leave the new one alone. i told her that an 03-04 cobra will have enough power and i'll leave it alone. BS i will.

agreed.


the real advantage of 3v and VCT is streetable torque. they make near max torque from 2500-4500. the disadvantage seems to be port balance. the cam profiles that 3v likes are exhaust limited. there is reversion into the intake tract when the exhaust timing gets large enough to make real power in the 6500 range. (480fwhp)

so there is no farther that intake cam timing can use for more air in, and in fact ther is a considerable reverse pressure wave into the intake port on 3v caused by the exhaust cam lobe using so much of the crank revolution and the piston being on it's way back up. that happens to all motors as the incoming air hits a closed valve, but it happens too early on 3v. 3v also hates overlap the lobe seperation increases with duration to 116.5 crank degrees to make good power. i can go on and on.

remember we are talking about 380-480 fwhp with the right combo. that's way short of 4v with ported heads, but great for the average joe.

4.6 3v is going to fall short of that. if someone pushes compression to 15:1 and uses a profile with 227in/239 ex duration .5in/.550 ex lift and 116 centerlines with 139/169 @ .200 lift he will max it out, but still fall way short of 4v with an fr-500 intake. stepped header /open exhaust.

anything 3v does 4v can do also and end up on top. i still advocate 3v for good power that's better than 2v, but it still has it's place below 4v. 4v is more expensive for bolt on parts.

that's a nutshell.

the wife is making it hard for me. i'll certainly give this site the first shot at the car/motor or anything else.

i have to agree to never mod again. she hates me wrenching.