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LOL , the reason I asked was because we keep getting people asking about aftermarket plenum chambers and comparing them to the 33 25DET item . I was wondering if the fact that NA engines only have at best sea level air pressure to charge the cylinders is the 34 25DET plenum going to do it any better in a turbo app . You would think that by having two inlets the cylinder distribution would be better than the single , granted no RB26 inlet though possibly of value if the bits were available cheaply .

Thoughts ? Cheers adrian .

I'll respond to the question with a question:

If there was an advantage to be had in forced aspiration application, do you consider the Nissan engineers would have specified it differently? ie. there would have to be a reason why they gave the pattern makers in the foundry two different designs for turbo vs naturally aspirated RB25.

Certainly sparked some conversation though. Good work :D

Actually looking at the pic above the 2JZGE looked a bit better probably larger to suit 3L . I wondered if feeding the six runners was better from two locations than one . I suppose if you look at the single entry 25 DET plenum the air is directed (straight shot) at the middle cylinders and has to turn corners to reach 2 and 5 and the furthest 1 and 6 . If two inlets were placed to line up with 2 and 5 would distribution be much better ie with the sorts of gas velocity needed to feed a 250-300 Kw engine . BTW I'm not after such power levels but it may get some what they want without spending furtunes .

Cheers A .

heres a good setup....wouldnt it be great if there was one throttle body for each cylinder. Sure beats the single setup and its gotta beat the twin na setup...whaddiya reckon mates? One big chamber that feeds individual throttle bodies for each inlet port....geez why didnt nissan employ me?

The real decision you need to make adrian is do you want the longer runners in your manifold for down low-mid response or the shorter ones like that in a 26 for the better mid-high range flow and response. You more concerned with road drivability or when you hit the track for some sweet circuit action? I reckon that makes your options a little simpler...however you already knew that. Id go 26 and adapt it. There are adapter plates for 26 inlets also im sure greddy make em or someone else. Surely 26 inlet systems arent too exxy? I looked at some ages ago when i was gonna use one, and they were only around 300 bux for whole inlet side. Dont know if thats cheap or exxy though.

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