Thor, You are right.

 

Thanks Thor01, Thats what I figured would have to be the set up if the stock manifolds fit. On the lincoln 4 valve head the extra exhaust ports require a larger manifold. I have to take a look at those heads sometime, I just don't see those motors at my shop, most of them are probably still under fords warranty.

 

As others have mentioned, the exhaust ports on the 4V require the use of a unique (Navigator 4V) exhaust manifold or, if you have the money, a custom-made set of headers. I will post some pics of the exhaust ports this week to give you an idea of the difference between the two.

Someone mentioned using 3V heads several posts back...while they will bolt to the block the same as the 2V or 4V heads, you will need a unique front cover, cam covers, intake and most importantly a processor to control the VCT (variable cam timing). VCT is the key to boosting the low end torque AND the high end HP plus it serves to regulate emissions (no EGR system on a 3V).

It will be a while before you see a 3V conversion kit IMO.

 

So your saying like with the lincoln heads, you have to change to headers, or larger exhaust manifolds?

 

As I mentioned, you have 2 options...procure yourself a set of stock exhaust manifolds from a 4V Navigator or have someone build you a custom set of headers.

 

So when Thor01 said on the ford, that 2 valves share the same exhaust port, 1 port per cylinder, what did he mean? I know what the lincoln 4 valve head looks like.

 

I think what he is saying is that there are 8 valves for the exhaust on each head but only 4 ports, 2 valves for each port. The port is just larger than that of a 2V motor.

 

well,

someone dyno this setup and give me some results, i may have to take out a loan lol

 

kidd2001,
PFA is correct. That is what I meant. The 2V exhaust manifolds will not work on the Lincoln 4V heads. Exhaust ports are configured differently.

 

OK, my final question is will you have to replace the exhaust manifolds on the L if you put on the FORD DOHC 4 valve heads. Sorry about all the confusion but this was also my original question. I was told on this thread that you did not have to change the exhaust manifolds. As I stated on page 3 of this thread, How can the kit be complete with heads, intake, and valve covers. I was just trying to say you also need to replace the headers too.

 

yessir, you will definitely need new exhaust manifolds to fit the 4V heads; your stock 2V manifolds will not fit.

I happened to visit a well-known engine builder recently who is in the process of completing a DOHC conversion on a 5.4L L engine using a (partial) stock intake and stock blower. This conversion and the test results will be featured in an upcoming issue of MM&FF sometime in the spring. The results should be interesting...if the thing makes the kind of power and torque that it is supposed to, I predict a lot of demand for the 4V heads.

 

Thanks for setting things straight ! I had originally posted what you just said, and appearently some people on this board think you can just bolt up the stock exhaust manifolds. Thank you again for confirming what I originally said when I entered this thread.

 

Hello,

2 questions...

1) If low end torque is in question due to loss of port velocity, why couldn't the Cobra IRMC system be implemented?

2) Phisically, will a set of Cobra or Navigator heads bolt directly onto a Lightning? If not, what is needed to make it work?

Thanks.

-->Greg

 

I believe one of the motors Ford is considering for the remade GT-40 is a 5.4 4valve withe the eaton blower intercooler. 500 hosses.

 

I don't believe low-end torque would be an issue with the blower, however if you have a complete Cobra setup including IMRC, you could probably use it. You would need a processor that is set up to control it though...not sure if one of the tuners could provide that functionality with just a chip...maybe one of them can jump in and answer that.

The 4V heads will physically bolt right on the Lightning (or any 4.6/5.4) block...the issues are coming up with an intake and exhaust system that will fit. The intake and exhaust ports are unique on the 4V heads. As mentioned in posts above, you could use 4V Navigator exhaust manifolds but they certainly don't flow very well. Jim at JDM told me he is able to supply headers that will bolt to the 4V heads in a Lightning application; you might want to talk to him for more info if you are serious about this.

Other issues are (potentially) needing different pistons - if you compare the F150 2V engine to the Navigator 4V engine, you will find the 4V uses different (flattop) pistons...I would have to assume that the unique combustion chambers on the 4V heads would require a unique forged piston to get the right compression ratio. Also, getting a processor/calibration to work properly and mating the EGR tube are other issues. These are just a few of the things I have thought of while contemplating this conversion...there are probably numerous other stumbling blocks you would run into along the way.