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they increase BHP by between 2-5HP


I doubt there are any independent tests of different inlet plenums, to confirm which is best, so like remaps, is probably a natter of opinion
 

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I think it comes down to how far up the mod path you are. If you just want a stage 3 car, the maps are written for basic stage 3.
You only get a plenum for 3 main reasons.
a) You're just wanting some flash looking kit underhood.
b) You're running almost all the mods you possibly can, and now have a map to suit over stage 3, so getting the parts that may add a horsepower or two, and also could aid reliability.
c) You run a bigger turbo (or an RS) and have higher boost pressure/volume that could blow the plastic plenum.
 

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they increase BHP by between 2-5HP


I doubt there are any independent tests of different inlet plenums, to confirm which is best, so like remaps, is probably a natter of opinion
Going by what ive seen of the insides the Anembo one is by far the best but is also the most expensive by a fair margin! It would still hardly make any difference unless you are running big power though!
 

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c) You run a bigger turbo (or an RS) and have higher boost pressure/volume that could blow the plastic plenum.
Blown plenums are an RS problem due to rubbish mapping! Its caused by the engine backfiring into the intake and not by boost pressure! You can stick 5 bar into the standard one before it goes pop!
 

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Probably bad inlet cam overlap when it shouldn't have overlap. Allowing the backfire to get past the valves.

I find the U412 map interesting. It feels to me that the cam timing is quite different to the DS tunes I used. Down low, the car feels really lively without much boost. It got back that lazy and torquey feel of the stock map where you can trundle about in higher gears at very low revs, but with a few more revs it's peppy off boost.
 

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Probably bad inlet cam overlap when it shouldn't have overlap. Allowing the backfire to get past the valves.

I find the U412 map interesting. It feels to me that the cam timing is quite different to the DS tunes I used. Down low, the car feels really lively without much boost. It got back that lazy and torquey feel of the stock map where you can trundle about in higher gears at very low revs, but with a few more revs it's peppy off boost.
Much like the MR290 map, certainly feel it much lower revs
 

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Much like the MR290 map, certainly feel it much lower revs
The dyno plots of MT and U412 look quite similar, I'd say the maps are possibly comparable to a point. The exception will be the MT use of stock airbox. The Pumaspeed maps cater to full intake and maintain the smoothness and boost control with full mods. I haven't seen plots of an MR290 with full intake yet, to know if the map can handle it ok and run as an MR320 lol
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Good insurance I reckon, I am sure there were some plastic plenums that were weaker than average. A bad batch. I do think they will help with a better intake fill with the right one.

I'm partial to one that has the larger ports to match the lower manifold.
 

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Blown plenums are an RS problem due to rubbish mapping! Its caused by the engine backfiring into the intake and not by boost pressure! You can stick 5 bar into the standard one before it goes pop!
I'm curious to know what happens when an RS with the upgraded plenum backfires - if the pressure is sufficient to explode the plasic plenum then if the ally plenum doesn't blow then the pressure either exits somewhere else or stays within the intake/cyl head area and could do worse damage like bend a rod or similar? Maybe a weak plenum is a good thing if you've got intake backfires?
 

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I'm curious to know what happens when an RS with the upgraded plenum backfires - if the pressure is sufficient to explode the plasic plenum then if the ally plenum doesn't blow then the pressure either exits somewhere else or stays within the intake/cyl head area and could do worse damage like bend a rod or similar? Maybe a weak plenum is a good thing if you've got intake backfires?
it would never bend a rod.
 

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hopeing to go down the route of ds turbo x,with AS big boost kit , so i thought i might need a plenium !!!
Its more of a nice to have than a need to have Vince.

Certainly wont do any harm and will give a small gain. I've always said the Mountune one i have was the mod that gave me least bang for my buck.

 
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