Gents,

Apologies up front for posting a question that may have been asked 1,000 times already. Searching has yielded some answers for me, but not exactly what I am looking for. I imagine many of you guys on here are familiar with trying to extract more power from the EFI 460, so here is my story.

My friend has a 97 F350 dually, automatic, with the speed density 460. We just returned from a 2200 mile round trip hauling an enclosed racing trailer from North Carolina to Iowa and back. The truck was fairly unimpressive in both the power and fuel mileage departments (Averaged between 5.5-6 mpg at every station) While that fuel mileage is dismal, I understand that it is a big block, so I get it, but I was really disappointed with the power output of the truck. It feels like if it is going to get 6 mpg then it should at least pull a grade without much trouble, as it is now you have to momentum drive the truck, if you stop paying attention for a minute you will find yourself doing 50 mph in the fast lane with angry people behind you.

As it sits now, the truck is 100% stock, right down to the original exhaust. It seems pertinent to say that this truck's sole purpose is to haul a racing trailer, it never moves without 9,000 lbs hitched to it. I have done some reading and I understand that a free flowing exhaust from the cylinder heads to the tailpipe will help the truck out some. I have also discovered that there are some EFI camshafts available.

My question is this, if a man wanted to REALLY extract a bunch more power out of this engine, what is a realistic goal for this engine with the factory speed density system? It is obviously limited compared to a Mass Air truck of the same configuration. What are the options for a guy if he wants this 460 to run really hard, if it is only getting 6 mpg already, how much worse could we make it?

Would it be best to convert the truck over to Mass Air, would it be best to remove the factory fuel injection system altogether and go to an aftermarket system like mega squirt or Holley? Would this open doors to a better head/intake/camshaft recipe that could be properly tuned, or can significant power be made with some combination using the factory fuel injection? If the factory ECU was ditched in favor of an aftermarket setup, how would one handle the electronically controlled transmission, a stand alone controller?

Pretend a guy came to you with this truck and said, I want you to build this truck to make as much power as possible while retaining all of the factory fuel management, what is the answer?



Thanks for any input

 

Exhaust, cam, compression, in that order then maybe a tune. I run a 1988 f-super duty 460. I regularly put 4 tons on it. I. Can run 70 mph no issues. I have a 3 inch exhaust running a cam and compression up close to 10 to 1. Yes gas mileage sucks but this one runs. Plus truck and. Bed weights 9,000 lbs so I some times weight close to 18,000 lbs. Rear gears are also an issue mine age 4:56 to 1

 

Cut out or replace the cat depending on your emissions requirements. Take out the tight turns in the exhaust ports by smoothing out the edges, and don't waste your money on headers unless you open up the ports to the max. Pick from the list of efi cams whichever company you go with. Speed density will not handle low vac at idle from a big cam so don't get too aggressive. I am still underway in my transition to maf, which is very nice for cam and tuning options. I did too many things at once and regret it. Compression helps, but going over 9.5 and running 87 gas doesn't work well. Bump the base timing up to 12 degrees. You must have 4.56 gears as well?

 

Do some searching and reading over there before you start asking questions. If you understand quench and static/dynamic compression before you ask you will probably get more out of it. The sky is the limit. The bottom of your pocket is the limit.

There are some good threads here too.

http://www.460ford.com/forum/37-engi...-upgrades.html

 

The speed density is the limit. There are many success stories of guys whom have executed an efi friendly cam swap with good results. That was my original goal until my builder threw in an xtreme energy 4x4 cam that the SD system couldn't run on. More my fault than his. The maf swap is doable but you have to get into a lot of tuning and extra parts.

 

This was my basic question/concern, I knew the speed density was going to be the limit and I did not want to head down one path and max myself out pretty quickly, when I could have headed down another one with a much higher ceiling. Thanks for the input on this.

The Ford460 forum link that the other guy posted up had most of the information I was looking for, all I was after was someone with some experience in trying to make a speed density setup make power. I think the answer that I have found is unless my friend wants to switch over to MAF, or a stand alone ECU system, then he is not going to make the gains that he wants to.

Thanks again.

 

I'm not sure why he wants the gains. In my head it wouldn't be worth the buildup and maintenence associated with a high power maf 460. If he wants better mileage with it, and still get the power bump for towing, then;
-swap gears to 4.10's if that isn't what he has
-set base timing to 12 degrees btc with spout removed
-cut out the cat, because it is likely part way plugged from getting 6 mpg
After trying these, if he isn't satisfied, I would go to an efi friendly cam swap, and blending the sharp casting edges in the exhaust ports/port matching.

 

MadPorter makes an SD crate engine do amazing things. If you didn't see that over at 460.com, go back. He seems open to helping DIYs but he earns a living doing this so he is "on the clock" while helping.

I looked at MAF conversions and it looks a hobby leading to the JY. A lot of what you read on this board is JY bound. A lot is sales pitch.

 

Thank you guys,

I am going to pass along the information you guys have given me and see where he wants to go with it. I think the first reaction was if he was going get fuel economy that was that poor, then why not shoot for the moon on power.

I am not sure if that truck has 4.56 gears, but that seems deep to me, I was thinking 4.10-ish, but I am not familiar with those trucks. If it does indeed have gears that deep then some 4.10's would definitely help the highway rpm.

It seems like the most logical thing to do is what you guys have said, start with the exhaust, see if that helps enough to make a noticeable difference and then decide if he wants to put any more money into it beyond that.

He got the truck from his Dad (who bought it new) and I think he is now leaning towards just buying a used Cummins for his trips to Iowa and back.

 

One area that is not mentioned, how is the platform maintained? Do we have good fresh spark plugs, a good fuel filter, good plug wires? Good cap and rotor? God o2 sensor? Has fuel pressure been verified? air filter? my 460s are towing machines even in our high elevation mountains and steep passes. However, if a fuel filter is restricted, a fuel pump is weak, plugs, o2 sensor, wires, cap and rotor, these things turn into turds fast. the 5 speed wears your right arm out. I hauled a 78 f250 4x4 on a big gooseneck over the highway recently with mine, 65 was no problem with 410 gears and a 5 spd. A good tune up might benefit before

 

Did you go through Parachute and Rulison? Did it glow in the dark when you got it home?

 

I have worked up there, in the past. No, I usually take hwy 50, "the backbone of america" but where it wasand where we were going, no parachute/rifle/rulison/meeker/palisade. I was the wrong direction, but ironically the truck was a drill rig, had a water well rig on the back, and a pto, but it is fine in the daylight or the dark. My other 78 snow fighter was actually a connors drilling truck for a number of years, it served some time over in the west end during the uranium boom. It doesn't glow either, but it should.

 

I drove rt50 across Utah and Nevada just a few years back. The idea that you can still drive so far and never see another being is alien in today's world. Too cool. I am due to get back out west.

Would you believe they detonated a couple nukes just southwest of Hattiesburg, MS? Operation Salmon.

https://en.wikipedia.org/wiki/Salmon_Site

 

oops wrong thread