were back LOL throttle body zs

[Drew]

http://www.dyno-plot.co.uk/dyno/dyno...er-200-lol.htm

cam and inlet length make the change.

Drew

[Fred68]

The standard Vis plenum is a clever idea but it's performance is hampered by the reliability of the motors and butterfly linkages. The idea Is to alter induction length to give a torque increase at key points in the rev range at a variety of throttle openings. After considerable research I believe the main idea behind the Vis system was to improve fuel efficiency and low to mid rpm torque at the expense of ultimate power. The cam timings don't help power ether as the inlet cam has only 238° of duration which would explain why a cam change, to even a mild 270° pushes power up considerably. Of course if you fit a set of cams in conjunction with the standard Vis plenum you won't generally see such good gains as with an open plenum simply because the Vis plenum is'nt designed to flow the volume of air required for 240 bhp (around 500 cubic feet per minute)!!
I'm pretty sure there is more power to come with the KV6 it's just working out what does and doesn't produce it? The open plenum does seem to work pretty well looking at the power graph of this one.

[stamford]

Don't you people ever sleep.............I'm at work and not thinking that technical yet!

[Eddie]

In my mind I see a V6 with many restrictions bolted to it, (stock KV6)
The static CR of the KV6 is fairly good out of the box 10.25 (5).1
The Static CR would make good use of the 270 cam profile with stock valves and standard cam pulley's.
The restriction is in the inlet and exhaust manifold arrangements, NASP tuning really is a black art and more attention to the engines flow should be considered when trying to produce additional power.
Many variables, all which have been discussed hundreds of times before shouldn't be forgotten, it's basic stuff that you can apply to almost any engine BUT it's the way you put these variable combinations together what counts.
As for why this particular set-up is making power the way it is could be the mapping, you can only map around what you have built and in my mind this configuration is an unknown untested quantity, the engine build will dictate what fuel and ignition it wants and where it works bests, Thor have maximized the combination of parts provided.
It's not taken the same shape as the stock KV6 power curves but why would it as much has changed and it makes power differently, not ideal if you like the delivery of the stock-ish engine but this was always going to be the case.
At this stage, I see the engine crying out for bigger cams, possibly some head work, and custom exhaust manifold set-up with the inclusion of a bump in compression.

[Jay-ZS+]

Originally Posted by Eddie

The restriction is in the inlet and exhaust manifold arrangements, NASP tuning really is a black art and more attention to the engines flow should be considered when trying to produce additional power.

Its not a black art at all its just involves lots of complex science. Turbo tuning is easy as you can just ram as much air in a possible and get over any flow losses.

I think the VIS system is a good concept, but its nothing new cars have had variable induction tracts for years, Porsche had a system back in the 50's cant remember the model of car off the top of my head.

The trouble is MG didnt make a great job of it. There are much more effective systems that can be seen in other marquees on top of this match it with a variable valve system gives decent torque, power and efficiency from engines smaller than 2L.

This makes me wish I'd gone for looking at redesigning the plenum for my dissertation. However the future of SI engines is a cam-less one

[grimmy]

[Smokey]

Wow, too much info that's beyond me!

[Quadcam24]

blumming hell the silence is deafening....where's the pics & vids, what t.b did you use, is it piped down to a cone in the inner wing ?, weve not even heard if anyones driven it !?!?!?!?
considering everything, its all very low key, wheres the drop jaw pod time, and the drooling mg fans pics of it a meet ? !

[grimmy]

[welshone]

Was thinking the same about the MG6