Help with Motor Build Plan_350-400HP N/A 2nd Gen 4.6L

[George R]

Buy a supercharged 5.4 out of a lightning or HD f150. So much cheaper than trying to build a 4.6.

 

[joethefordguy]

Oh, where to begin but I will be brief. I should have pointed out in my first reply to your "get an Ecoboost" reply that you are one of those people that either doesn't read the OP or does read it but decides to post a reply that is not even relative to the OP.

It should have been obvious to anyone reading my OP that if I wanted to replace my "16 year old jalopy" I would not have spent the money to upgrade but would have replaced it. I don't want a ******** Ecoboost. So, unless you have some suggestions that are relative to my OP, post them. Otherwise go find someone else to bother.

To the Ignore list you go.

I have to agree with you; there are few posts as irritating as those from people that insisting on ignoring the OP and pursuing their own agenda - practically hijacking your thread for their own purposes.
I've been researching almost the same as you, but I'm looking at the 5.4 2V. If I already had a 4.6 as you do, I would definitely stay with that - I owned one for over a decade; it was one of the best cars I've ever driven. powerful and efficient from the first day to the last.
I'll throw in a couple of things I've learned in my research (looking up 5.4 stuff yields a lot of 4.6 info): Headers really have an effect on torque - you might want to consider that in whatever you do. For my truck, for example, moving the torque curve higher up the RPM band is money down the drain.
And, I have read, I think, that the best/strongest cranks for these engines is the steel 8 hole one. FWIW.

It seems to me that you are on the right track. Good luck with it!
jg

EDIT: PS I should have said I have no interest in paying tens of thousands of dollars for a new or nearly new Expy, or whatever, when I have one that is already 90% of what I want for a hell of a lot less money, and avoids the compromises of a new model.

 

[HawkX66]

Planning to build such a motor for my '03Expy and want to collect any thoughts from forum members that may have experience with building up the 2V 4.6L motor.

My first thoughts was, of course, building a nearly stock motor and supercharging but I would only do that if there was a "bolt on" package and I have not been able to find one.

I would not rebuild the motor (160K) that is currently in the vehicle which has been mildly modified with under drive pulleys, electric fans, shorty headers, CAI and a 5 Star tune. I expect HP has been increased from 232 to 250-260; I can hold my own with my workmates later model F-150 EB 5.4L. So I am looking at picking up 100HP, naturally aspirated which I believe doable. Also added 4.10 gears and it moves out smartly but far from a barn burner.

Generally, the plan includes:
-overbore to establish a true bore; .010"-.020"
-increase CR from 9.4 to say 10
-have heads ported or go to aftermarket (one of the best head porters in the country is 45 minutes away and a good friend)
-new intake manifold (no idea what is available)
-mid duration cams, say 235*-240* intake and exhaust
-replace crank with something stronger (no idea what is available; have been told the OEM crank will hold up)
-retain CAI; maybe need to replace with something that flows more air??
-retain shorty headers (I know, full length would help but I don't want to get into modifying the exhaust)
-tune to pull it all together.

Plan B is go to aftermarket for crate motor and heads but haven't researched that option/cost/complications? yet.

Any suggestions from forum members are welcome but don't tell me to replace the 4.6L with a 5.4; not going down that road.

I built a Romeo block 4.6L for my sons 02 Mustang. His first car. Great little motor and easy to build. No idea on HP. I wasn't trying to go nuts with it. I have a 525hp/550tq big block that I run in my 69 Camaro though, so I do know how to build for power too.
1. Boring out 10 or 20 isn't going to do much of anything. Start thinking at least 30 over. I'm not sure what the 4.6L can be bored out to.
2. CR. .6 bump isn't going to net much of anything. CR is however a big key in HP. I left my BBC at 10:1 because I like running u/l pump gas and not worrying about detonation.
3. Heads. Huge if you know what you're doing. They can make or break a build.
4. Intake & injection. Again, important. Fuel pump upgrade will probably be necessary and maybe lines depending on what you do.
5. Cam. Call someone like Straub. Very important. Don't just throw numbers out and pray. Get someone that knows what they're doing to spec one out for you.
6. Crank is probably fine, but check out the Mustang sites and see what they're doing.
7. CAI may or may not be necessary. A lot of snake oil out there. Headers and exhaust will be necessary.
8. Tune important once you have your motor built and the specs ready to give a real tuner.

Plan B. Totally depends on you. I like building my own motors, but I know how to and I've had the area to do it.

 

[joethefordguy]

[QUOTE="...

Generally, the plan includes:
-overbore to establish a true bore; .010"-.020"

...[/QUOTE]

sorry, i forgot to ask, what is a "True bore"?

I am not a mechanic. I've done some work, including replacing an engine, but I am at best a "parts changer". Before I do anything, I research here, other forums, google, youtube, etc. so far, so good.
My intent is to increase available torque low in the rpm band, preferably without passing more fuel through the engine or regearing.
the only mods I know I'll be doing for sure are the electric fan swap, possibly a better radiator, mild suspension lift to fit taller tires (might regear for this), a tuner, skid plates, probably some kind of exhaust upgrade, better lockers, and so on.
jg

 

[HawkX66]

[QUOTE="...

Generally, the plan includes:
-overbore to establish a true bore; .010"-.020"

...

sorry, i forgot to ask, what is a "True bore"?

I am not a mechanic. I've done some work, including replacing an engine, but I am at best a "parts changer". Before I do anything, I research here, other forums, google, youtube, etc. so far, so good.
My intent is to increase available torque low in the rpm band, preferably without passing more fuel through the engine or regearing.
the only mods I know I'll be doing for sure are the electric fan swap, possibly a better radiator, mild suspension lift to fit taller tires (might regear for this), a tuner, skid plates, probably some kind of exhaust upgrade, better lockers, and so on.
jg[/QUOTE]
When something is true, it's straight. Complete waste of money in this case unless there's reason to believe there's a problem with the bore. If you're boring for cubic inches ie .030" or .060", that's a different story.

 

[joethefordguy]

Planning to build such a motor for my '03Expy and want to collect any thoughts from forum members that may have experience with building up the 2V 4.6L motor.

My first thoughts was, of course, building a nearly stock motor and supercharging but I would only do that if there was a "bolt on" package and I have not been able to find one.

I would not rebuild the motor (160K) that is currently in the vehicle which has been mildly modified with under drive pulleys, electric fans, shorty headers, CAI and a 5 Star tune. I expect HP has been increased from 232 to 250-260; I can hold my own with my workmates later model F-150 EB 5.4L. So I am looking at picking up 100HP, naturally aspirated which I believe doable. Also added 4.10 gears and it moves out smartly but far from a barn burner.

Generally, the plan includes:
-overbore to establish a true bore; .010"-.020"

...

Plan B is go to aftermarket for crate motor and heads but haven't researched that option/cost/complications? yet.

Any suggestions from forum members are welcome but don't tell me to replace the 4.6L with a 5.4; not going down that road.

While I don't agree with Hawkx66's premise, he did prompt me to ask a question. In your OP, you said you would NOT rebuild the motor currently in the vehicle. a crate motor is Plan B, so I assume the "-overbore to establish a true bore; .010"-.020"" is Plan A. what motor would you be overboring?
jg

 

[HawkX66]

While I don't agree with Hawkx66's premise, he did prompt me to ask a question. In your OP, you said you would NOT rebuild the motor currently in the vehicle. a crate motor is Plan B, so I assume the "-overbore to establish a true bore; .010"-.020"" is Plan A. what motor would you be overboring?
jg

What's my premise that you don't agree with? That it's a waste of time over boring for a "true bore" or my response to your question of what a "true bore" is?

 

[joethefordguy]

I misread your post. I disagreed that overboring was a waste, but I do agree with you that overboring for a straight bore in the absence of evidence it is needed is a waste.
sbt.