I just read in mustang and fast fords mag a very informative article about the 4.6l engine (Dispelling modular myths). The long and short of it is that bolt ons just do not help this engine due to the fact that the heads are the restriction in the airflow path. The ford engineer Andy Schwartz has the experience to back up his claims!

Quote "exhaust is a waste of money" "the 2 valve engine needs heads and intake manifold"

Headers = 2 to 5 hp
aftermarket mass air meter 10 hp $400


I installed headers, gibson ex and KN filter with airbox mods and a chip: net result no significantly measurable change in performance. By that I mean at least a 0.2 sec increase in 0-60 or 1/4 mile.

1000 dollars for nothing! I wish I had known before I purchased the stuff.

So now you know the real truth, with out FRP (svo) heads and an intake or a blower the 4.6l is not responsive to bolt ons.

Chris

ps. the fuel economy is lower also, down to 14.3 hwy and 10.7 city from 17+ hwy and 13city

Oh yeah I was stupid the day I posted this and mis-spelled benefit, However I could not figure out how to edit the header on the post.

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98 SC 4.6L stepside, Gibson headers, Gibson single exhaust, superchip, Intake mods, Piaa's, high end audio stuff.

[This message has been edited by cujet (edited 11-07-1999).]

 

FINALLY someone else that recognized NO gain from the airbox mods and freer exhaust!!!!

Standing by with the fire extinguishers.

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1999 F250 SD CC, LWB, 5.4L, Auto, 3.73, 4x4, Power TT mirrors w/ marker lights, White, Full Tint, PendaPro SR, Flowmaster Delta 40 series, K&N filtercharger, Superchip(Airbox removed for a second try, maybe in the winter it will be advantagous?)

 

Didn't expect much either. Snake oil comes in all kinds of packages. So instead of making decisions based on performance expectations I went for looks, sound and any cheap "no hurt" alternatives I could find. In that order. You can't be disatisfied if you don't get your hopes up too far. Yes, indeed, the flames will come!

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97 F-150 SC Lariat, Styleside, White over Gold, 4.6L (Windsor), Automatic, 3.55 rear end, electronic 4X4, w/ every option of Lariat and ORP packages except the 17" wheels and the 4X4 decals, MODs so far: K&N air box mod, Gibson Super Truck, clear Bugflector II, Leer TSC 600 hard cover, Bridgestone Dueler OWL ATP 265/75 R-16's, TrailMaster Invader N7 shocks, Smittybilt step bars, Ford moulded mud guards, "White-white" head lamps.

 

What, who buys exhaust for power. I always buy loud exhaust to turn heads and make people see how beautiful my truck is.

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1997 F-150, 4.6, automatic, Dark Toreador Red, Supercab, Flareside, 4X4 Off-Road, Towing Package, Chrome Grizzly Wrap Around Push Bar, Ford bedliner, Code Alarm Sure Start RVS remote starter, and Lots of TLC!! (Besides being an F-150 nut, I am a Ford auto technician.)

 

Are we comparing a 4.6 in a Mustang to 4.6 in a F-150? Aren't the heads and the intake different? Would the intake on the F-150 fit under the hood in a Mustang. I haven't timed my truck after the mods, but I make it up the hills easier and quicker without down shifting. Just my .02 worth, just a reminder to disconect the battery after each mod, this does make a difference.

 

Bigred2 you are correct the heads might be different depending on year and the intake is different. Even the pistons are different. However the differences do not help power output. floating piston pins do nothing for flow rates in the head and do nothing to the compression ratio. The intake is longer for more low end and is quite restrictive. the heads may or may not have minor changes in them for smog reasons and do not have the bigger valves, bigger ports and unshrouded and repositioned intake valves that are necessary for HP. In short it has the same performance and same smog stuff an the stangs

Chris

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98 SC 4.6L stepside, Gibson headers, Gibson single exhaust, superchip, Intake mods, Piaa's, high end audio stuff.

 

I believe the floating piston pins are only in the windsor version of the 4.6L anyway but you are correct they do nothing for HP.

 

First of all anyone who thinks by installing any combination of bolt on parts they will have an instant hot rod pick-up is mistaken. Bolt on mods are not going to make a 15-16sec 1/4 mile pick-up into a fire-breathing monster truck. They are only to give that small (not a seat of your pants) improve on overall performance. Without dyno reading and/or 1/4 mile times the gains may never be seen. thats my 2 bits.

 

Jason, I did not expect 50 horsepower by the various mods I have done, however the fact that no gain WHATSOEVER resulted from the mods is troubling. I do have experience and know how from 25 years in the race car business (IMSA and SCCA). I also spent quite a bit of time recording and posting the results of each mod. What I have found is EXACTLY what Ford engineer Andy Schwartz says in the MFF mag. I believe that many trucks and cars respond in a much more favorable manner to mild mods. A few examples, Jeep gramd Cherokee V8, Dodge Dakota V8, older Chevy pickups with V8's ALL PICK UP HP WHEN PROPERLY MODIFIED! The ford 4.6l does not! Did I expect more power, you bet! My truck runs out of steam at 4500 RPM, I was hoping to extend the powerband to above 5000 RPM. The new 'stangs (with the updated heads) rev right past 6000 RPM.
Call me an idiot but past experience led me to do these mods, and I expected similar results to what I have had in the past, a freer revving more powerful truck.

Chris

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98 SC 4.6L stepside, Gibson headers, Gibson single exhaust, superchip, Intake mods, Piaa's, high end audio stuff.

 

You won't get flamed by me because you have discovered what drag racers have known for years. One of the most important peices on a drag engine is the heads. The big carb and cam, and thee fre flowing intake and exhaust will not do you any good if is all restricted in the heads. Now I am not saying that bolt on will not make any difference. Some should make a bit of differance but not a huge one. But I am willing to bet that if the only bolt on you added was a free flowing set of heads and NOTHING else most of you would be in shock the first time you mashed the gas pedal. Sorry to be so long winded and I am NOT knocking bolt ons. I have added some to my truck. The point is I don't expect exhaust and an airbox mod or adding an Airaid or similar setup to make a huge difference. I am surprised that your chip didn't more of a difference. To everyone alse if you want the stuff go for it! I will probably be right beside you in line But like someone said previously don't expect your truck to magically tranformed into an instant hot rod.

[This message has been edited by ps398 (edited 12-06-1999).]

 

I wish this topic was in the aftermarket or engines section where everybody would see it.
There IS however a VERY noticeable differnce between the 5.4l and the 4.6L.
Best $800.00 or so performace mod going.

 

There can't be that much of a difference between the two: I have a 98 5.4L 4x4ORP with 285s i have true dual 2 chamber flowmasters, a chip, K&N filter. My bro has a 97 4.6L 2wd no mods.

Both have 3.55 gears.

After a stop sign, there is a straightaway, at a certain point we always measure by, my truck is at 84 mph, his is at 85, and yes, I have recalculated that my speedo is off by 3.2%

What is up with that?

 

Well for sure the 4X4 weight is an equalizer of some factor. What type cabs do you have? I'll bet your sounds better!

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97 F-150 SC Lariat, Styleside, White over Gold, 4.6L (Windsor), Automatic, 3.55 rear end, electronic 4X4, w/ every option of Lariat and ORP packages except the 17" wheels (I even got the OR decals now!), MOD's so far: K&N air box mod, Gibson Super Truck, clear Bugflector II, Leer TSC 600 hard cover, Bridgestone Dueler OWL ATP 265/75 R-16's, TrailMaster Invader N7 shocks, Smittybilt step bars, Ford moulded mud guards, "White-white" head lamps, Bosch platinum + 4's.

 

they are both single cabs, his is long wheelbase, mine is swb flareside

 

Well for one other thing, other than the 4X4, your effective gear ratio is no longer 3.55 because of the tire swap. Remember this site?
http://www.4lo.com/