derek173

iTrader: (3)

maybe this is a dumb question

but has anyone had their mrev or lower plenum ported/polished, would any gain be seen by this on a NA application or is it pointless?

Abishop

iTrader: (19)

well, you would think motordyne would make the mrev the best they possibly could make it, no?

derek173

iTrader: (3)

yes I agree but would also add to the cost so maybe not?

Abishop

iTrader: (19)

Well theres only one way to find out, dyno, polish, and dyno again........

SpeedRcr

iTrader: (5)

they did, tony did it and for the time and effort he yielded another 1-2 hp at best...

first350

iTrader: (24)

check out the DIY plenum thread...lots of talk about polishinng the plenum - general consesus was that it would hurt flow (other applications and books say that a polished surface changes the flow characteristic of the boundary layer and actually causes more resistance)...it's supposed to have a certain amount of roughness. Porting it would help ~ but this take a long time! I've been working on my own, and it's a huge pain...I can't really see a way to automate this process, so the cost would be fairly high.

Here's 2 pics of me trying to port match the lower plenum to the collector:



I also milled off the top of my runners similar to MD's lower plenum - I spent another ~3-4 hrs smoothing out the transistion of the milled out area so that it didn't look like a 'flat top'. After doing all of this, I'd say buying the MD lower plenum is well worth the $.

Here's a pic of my lower plenum (I painted it w/ a high temp ceramic paint - I did that to lower heat transfer and hopefully give the surface a more uniform texture so that air flow wouldn't be weird:


-Peter

derek173

iTrader: (3)

thanks peter!