Hypothetical question (intake manifolds)
 

If the V12 intake manifold & filter assembly could be redesigned from the ground up and offered as a drop in replacement for the stock unit what characteristics (technical or cosmetic) should it have?

I know AJ6 Engineering used to offer enhanced versions with flow matched runners and trumpets added inside but this service was discontinued due to health/age issues.

There was also a fellow here awhile ago with Group A? manifolds he was making which had several improvements but no doubt cost a fortune to build, but I'd rather explore options for something better rather then reinvent a poorly made wheel.

Personally, they look pretty. But they aren't as efficient as they could be. I'd see if it would be possible to form them like the Volvo B6304S1 intake manifold is. All runners are equal length and start from a ball. Like that all air is taken in correctly and perfectly. Or another way, have 6 individual throttle bodies right in front of the head ports.

Maybe even a switchable intake runner, like many smaller 4 cylinders have to up the torque at lower rpms and up the hp at higher rpms.

Thanks,

I have a set of manifolds sitting on my coffee table...thats normal right? ...anyway after spending an entire saturday polishing them I wondered if it was worth extruding/flow match and ceramic coating them or having a CNC shop design something better or some improved variation. My original plan was to have the spare set enlarged and smoothed out then coated because it's only $200 here to do them, and there were proven hp gains when heat shielding was used under the manifolds in track/race applications.

As with most Jaguar things if your going to spend $xxxx for questionable gains, why not spend abit more and go all the way? There are a handful of shops in north america and australia that could easily fabricate something better its just a matter of setting the parameters for the design.

I have a spare set of crossover pipe fittings I could add a second pipe on the front of my car and see, if nothing else it would make for a saturday well spent.


Another question I had was what exactly are the design changes through the years with these manifolds? there are multiple part numbers on the jaguarclassicparts website diagrams but aside from overrun valves and other non-critical stuff it isn't immediately apparent.

cylinder heads are the main air flow restrictions, the Jag V12 was never designed as a REAL Hi-performance engine!

it was designed to be smooth ,no vibration, and have 12 cylinders, (Ferrari ,etc). all selling points back 40/50yrs ago!

i still love the damn things , one of my 1st cars was a 12 cylinder Lincolns.

ron

Thats abit more complicated then what I was thinking, but it is one of the images that inspired my quest. A universal easy drop-in solution that plugs into the existing throttle/fuel assembly is more marketable.

The GRPA manifolds are useless on a 5.3L road car, they don't make power until 4500rpm+, so unless you plan on a min of 7500rpm redline do not go this big with the runners.

A friend of mine has built a lot of high power Jag V12 race engines including engines for Roddy, his advice to me for intake manifolds was, use the stock runners and add a larger plenum, 100mm (4") square and move the TB's to the front.