I have a 1997 F150 with the 4.6L SOHC V8. If I were to take a 2003 Cobra 4.6L DOHC V8 and put it in my truck, what complications would arise?

1) Would I have to alter any part of the fuel system?
2) Would the wiring have to be changed?
3) What exactly would I have to change to make this swap possible?

Thanks in advance.

 

I don't know about that part of it, but I can tell you that that motor sounds great but it belongs in a mustang. Not in a big truck like you have. They don't have the low end power to make it a good truck engine. It'll be powerful in a truck, but all that power is up high in the RPM range, not low where you need it in a truck. You'd be better off with an engine set-up for a truck with 390hp hehe.

 

There really isn't a whole lot a person can do to those modular engines to make a "truck" engine vs. "mustang" engine without alot of unnecessary work. The supercharged 4.6 cobra engine would probably outpull the truck 4.6 throughout the powerband by a large margin, and phenominally better on the upper end. In the 5.0 truck vs. 5.0 mustang its a completely different story.

However, I have never even heard of anyone doing such a project. That would be awesome if you had access to the engine and time/patients/money to do it. But no help here....I basically know what they (modular engines) look like under the hood and that's about it.

 

Alright, if I decided to go with a 5.4L longblock from Sean Hyland Motorsports, what types of modifications would I have to make?

This engine would produce the low-end hp/torque for my truck, but I could really live with either.

 

If you have an automatic tranny, then the biggest hurdle would be to get the electronics from the Cobra to work with your transmission. It can be done, but it is not cheap. The best way would be to get the engine and bring all of it's electronics with it. Harness, ECU, everything. It really wouldn't be that hard of a swap. Motor mounts and transmission will all bolt right up.

As to the power thing. The new Cobra's with the SC on them produce a ton of low end torque. Much more than you have now. That's the benefit of forced induction.

The best thing would be to just get a 5.4 shortblock from SHM or someone else then slap some 32V heads on that. Then put an ATI SC on there. You could be making upwards of 1000 hp with a big enough blower. Did I say big enough blower? I meant wallet!!!

JJ

 

Superchargers don't do much for low end torque, anything under 2k doesn't get full boost, and that's if it's a Kenne bell twin screw. Other types might be even higher for full boost.

 

lucky for me, with my new 4.10 gears I don't see much below 2000rpm, especially if I turn off OD.

Both the Eaton and KB SCs I'm looking at achieve full boost by 2000rpm...much better pricewise than the centrifugal ones that don't get full boost until 4000rpm.

Which brings me to another question...Which type would you recommend? Twin-screw or roots? The Eaton would be nice, seeing as it has an intercooler to keep the air nice and cool, especially during the summer...but KB says its SC doesn't need an intercooler...hard to believe

Any suggestion is helpful.

 

I was looking through the newest issue of Hot Rod Magazine and on page 106 on the very left it has an add for Crower. An add for 5.0L and 4.6 parts, brand new 4.6L modular cams for sohc or quad cams... the add doesnt say anything about cranks or rods or anything like that, just cams fort the mod motor, the 5.0 and rods for the 5.0 , 2.3 and 2.0 L ford engines. Just figured i'd let ya'll in on this discovery if your interested... im planning on getting a 99+ Crown vic with the police package and these cams might wake the interceptor up a bit more .

 

Ya but you still spend most of your time 2500 or below, it will only achieve full boost when there is a load on the engine (ie hard accleration). You'd get like 4 mpg if you spent most of your time above 2000. In my opinion there are better ways of getting 400hp under the hood.

 

well, I'm all for opinions on increasing horsepower...after all, that's what I'm trying to do

For my truck though, the only other one I can think of is replacing the engine...now I'm starting to lean toward a 5.4L DOHC Navigator engine, though...since the swap would be much more sensible than a cobra engine

 

The most cost effective way to hop up the mod motor is a supercharger.If you don't think you can make low rpm HP and torque with a blower check out the lightning specs.I would go with the positive displacement style over the centrifugal for a truck.Modding the mod motors is expensive.Just go price a set of cams or an intake.
Dollar for dollar the s/c is your best bet.How much HP are you going to make with a stock 5.4 navigator engine?By the time you swap out engines and mod the 5.4 you could easily pay for a supercharger.

CB

 

The stock navigator engine would be putting around 225 to the ground, which is just 15 less than what my truck would be around with a supercharger (that is if I got an Eaton, which, according to a dyno sheet on their page, shows the 4.6L with an 80HP increase...my truck was dyno'd at 160.3hp).

After swapping the engine, I would still plan to add a supercharger later on in the year to take it well over 300hp.

I'm gonna go try to find some nice cams and intake for my truck...I'm to the point where I'll do anything to increase hp

If anyone has any suggestions for a good intake, throttle body, cams, whatever that will work with my 1997 4.6L then feel free to let me know

 

ok, this forum is pretty interesting, so far i'v seen a lot of info about mods to the 4.6 and 5.4 liter engines, including cams and heads for a 5.4, I have been looking all over the place for heads and cams for my 5.4 liter v8 and havent seen any, as soon as i have enough money I will be throwing in a supercharger. I was thinking of a kenne bell but I want a supercharger with an intercooler so eaton is sounding really good. Didn't know there was 2 different types of blower that you could get the twin cam and the roots, which is better for power in a truck, i hardly ever get my truck over 4000 rpms even when i'm flooring it, any suggestions on which would be better?

 

You'll definitely want either a twin-screw or roots-type supercharger, both achieving full boost by 2000 rpm. A centrifugal supercharger (the most abundant type) requires very high RPMs in order to achieve full boost(usually 4k+).

The decision really comes down to 1) price and 2) personal preference. A twin-screw like the Kenne Bell is more efficient temperature wise and doesn't need an intercooler, plus it costs a little less ($500-700 less). The roots-type, Eaton, puts out a little more power and requires an intercooler to keep temperatures at a respectable level, but is more expensive.

I still haven't decided which one I'm going to get...it's a hard decision. Good luck choosing one.

 

Thanks for the info, you think it would be possible to get a kenne bell then mount someone elses intercooler to it to give a few more horses?