Is it possible to intall the 3v heads and intake on a 99 v10? Anyone know around what compression it would have and can I still use the 99 pcm? Anyone have any info thoughts ? Thanks lmk

 

None of the 2V PCM's will work properly with the 3V cylinder heads. The CPS is on the opposite bank, and then you'll have to fabricate some way to actuate the throttle body that's usually controlled by the PCM on the 3V engines.
As for bolting on and functioning, the shortblocks are the same-it's all of the top end that's different.
JL

 

Well the throttle body is no problem a regular manual one would be made to work. What is the cps?

 

Cam Position Sensor.
No way to fix that.
JL

 

You dont think there is a way to make or fabricate it to make it work? Also would the 3v heads give me much more hp than going with 2v pi heads?

 

There's no provision to mount the CPS on the driver's side of the 3V timing cover, no way to make the 2V timing cover work, the CPS boss is cast into the timing gears, and the 3V lacks this on the driver's side cam gear. It's unknown as to whether the 2V cam gears are indexed in the same manner as the 3V parts in reference to the timing marks and the keyway, so there's no way to know if you could swap the gears and use it like that.
Owning both verisons of the 6.8L, I can tell you for certain that the 3V is a night and day difference in power over the 2V. You're just gonna need the 3V PCM to properly control it, which also means that if you're older truck has a 4R100-you're gonna have to swap transmissions too-the 3V PCM's will not control a 4R100.
JL

 

Well a friend of mine has a really nice machine shop where he can fabricate just about anything. So maybe he can make a cam gear work. But as for the pcm can it be modified to work with the 3v heads? Thanks lmk

 

As far as spark tables,etc..yes, it can be reprogrammed to function properly with the 3V PCM.
JL.

 

Anything is possible with enough motivation ($'s)

If you go ahead with this, PLEASE take pictures, especially when you get to the cam gear.

Someone here once did this, and the problem he eventually had was the check-engine light on for the cam position sensor (CPS). It ran, and apparently had more power than the 2-valve, using the 2-valve PCM, but he had that check engine light on.

He had to fabricate an adapter to get the 2-valve throttle body to match the 3-valve intake, and he fabbed up some type of vacuum-operated setup for the variable plenum which (to me) was not optimal.

But the real bug was the CPS. I suspect it is somehow electrically different, not so much position, but signaling.

 

Well there has been a couple of guys doing this conversion on 4.6 engines. Logan motorsports sells a kit for this conversion aswell as mmr. I dont want to install the variable plenum. But what I realky want to know is if the 3v heads are gonna have much more hp than doing a pi head conversion on a 99npi block? I know if I put some pi heads with the raised cr it would give me maybe 40 more hp. Anyone know what cc is the cumbustion chamber of the 3v head?

 

Mustangs with 4.6L's and trucks with 6.8L's are completely different worlds. DO NOT assume that something will work, or that it's doable just because somebody's done it on a totally different chassis/vehicle class.
You don't get a choice on the variable plenum-it's an integral part of the 3V 6.8L intake manifold.
NPI heads=52cc
PI heads=44cc
3V heads=50cc

JL