Power gained from a VVC Inlet Manifold? How Much

[tnjjeffrey]

There seem to be a lot of the inlet manifolds available on ebay - what power gain would i get out with my standard 2001 elise, e.g. the mgf engine?

example of item bellow

http://cgi.ebay.co.uk/vvc-inlet-manifold-mg-rover-...

is it worth it? much faster? very cheep at £75!

[JTBUSH]

Dont think youd get anything. In fact, sure youd actually lose performance due to being heavier than standard item. Plus, the alloy one there will retain heat, where a plastic one doesnt, therefore your intake temps will be slightly higher than the plastic version, thus loosing performance. Really isnt a worthwhile mod I dont think!

[M7RT V]

Unless you've had the head ported to match the size of the aluminium inlet you won't gain anything, some people say it can even rob you of power.

[Esprit]

On a standard engine it'll lose you power.... make the head breathe a bit better and it can help a little

[Gallandro]

you will lose torque

i did it - and put the plastic one back on.

the idea is the VVC has a bigger chamber - but for more torque
you need the chamber smaller so the air flows through faster.

If you get the head ported as mine is - then the VVC will give you
a bigger slug of power at about 5,000 rpm - but your so slow getting
up to that its not worth it - so i changed back.

It might work better if you changed the cams and get an emerald ecu
but all your doing is moving the power up the rev range so car wont feel
faster until you rag it

chepest upgrade is to get a 4-2-1 manifold, de cat - ported head, with
a decat and sports exhaust - then you should see 145lbs torque and 150bhp

hope this helps

[lamb jiblets]

Gallandro said:

you will lose torque

i did it - and put the plastic one back on.

the idea is the VVC has a bigger chamber - but for more torque
you need the chamber smaller so the air flows through faster.

If you get the head ported as mine is - then the VVC will give you
a bigger slug of power at about 5,000 rpm - but your so slow getting
up to that its not worth it - so i changed back.

It might work better if you changed the cams and get an emerald ecu
but all your doing is moving the power up the rev range so car wont feel
faster until you rag it

chepest upgrade is to get a 4-2-1 manifold, de cat - ported head, with
a decat and sports exhaust - then you should see 145lbs torque and 150bhp

hope this helps

Um not sure about all of that, I to have a vvc plenum on my S1 with a PTP head and ITG, the diffrance is noticable all the way, As the engine is pulling air in if you restrict it you will have less power, to make the engine more ifficent thus more powerful you need to get the air in and the exaust out as quick and equal as posible.the vvc plenum has an equal size outlet to the block so can be faired in the plastic versin is smaller and ruffer causing air flow problems, but changing to the vvc on its own is off no benifit. the best thing you could do is take off your std manifold and clean out all of rovers crappy welding and open it up heres a pic of mine before and after.