VK engine question

mhgsx said:

Hello all:

I'm new to the FX community (just got a 45 2 days ago) and am in search for information about my car.

Is the physical dimensions of the 4.5L and 5.6L VK engines the same? I would assume that the 5.6L is just a bored and stroked derivative of the 4.5L. Is there a difference of heads used, or is the casting the same?

Since there really isn't much aftermarket support specifically for the 4.5L V8, I'm looking for 'alternatives'. And that leads me to the 5.6L. I know the JBA already makes a set of headers for the Titan/Armada. Since both engines are of the VK design, those headers should work, right? The only problem might be chassis clearance of the headers.

What do you guys think? Maybe this has already been hashed out??

Click to expand...

god bless you mhgsx.......

please follow up on your progress.....

as for needed power, you're on the right track, i believe

(((perhaps you can testfit the RHS tubes on a wreckeryard motor???))) i think, if you know a few peeps, you can find one torn down somewhere....

es

ps- are they eq. length?? shorties?? replacing the cats??

do tell!

pss- i think the 5.6 ( V ___?) is stroker VK ; the bore may be somewhat close (it is more trucky-torque making)

http://www.jbaheaders.com/headerdetail. ... tNum=1400S

Hot ****, 6 hours to install. Looks like we'd have to cut and weld flanges.

From the pics, they're obviously unequal-length shorties.

When I went to the Chicago Auto Show this past year, Nissan had a chassis and engine on display of the Titan. If I remember correctly, they had on some POS log-style header. Briefly looking at our exhaust manifold, it looks like the same lame design.

At least, the 6.0L engine on display of the new C6 Corvette and had equal length shorties STOCK.

I can see why JBA went this route. It's illegal to remove, replace, or alter the positioning of the stock cat-cons. So they went this route w/ the hack and weld design.

But I'm sure there are MANY like ME who would ONLY use the vehicle for OFF-ROAD purposes, NEVER to be driven on a PUBLIC ROAD if we were to fabricate a full header w/ the removal of the pre-cats.

I think the fact that the JBA design takes too much effort for install, we'll see a Borla header (maybe $tealin' ) which will have the 'for off-road use' warning on them.

Either that, or I'm gonna find someone to copy the JBA setup and weld up a full, BOLT-ON header setup.

Also what do you mean by "RHS tubes"?? Right hand side tubes? Any reason in particular for the right side? Tighter clearances?