20V Turbo Plenum with Velocity Stacks

[Bazooka]

I know they exist as an aftermarket product but I cannot find much information on them. Does anyone know where they can be found? I am specifically looking for a RWD plenum with the velocity stacks. I found a FWD item on Ebay -

http://cgi.ebay.com/ebaymotors/TOYOT...QQcmdZViewItem

[Billzilla]

They're typically called inlet trumpets in Aus, you may have more success searching for those.

[Bazooka]

Sorry Bill but I was searching under velocity stack as thats what their known as to the Chinese who are the ones most likely to make (read replicate) something like this

[JP]

You can buy stacks etc to make your own from http://www.jntperformance.com.au/

[charged]

Meridian motorsports or toy tecno tunning make them also, I got some off MM and they quality was great

http://www.mmsport.com.au

http://www.technotoytuning.com/index2.php

[roadsailing]

those ebay ones look pretty rough, especially for the price.

on a turbo i'd wand the bellmouths (or whatever you want to call them) to blend smoothly into the plenum, possibly on an NA engine too.

[rms]

Like this ?

[MWP]

Hasnt it been proved somewhere that having a lip on the mouth (not rolled all the way around like on the T3 bell mouths) is actually better for flow?
Im sure someone on here did some tests on this...

[The Real Roadrunner]

nope, at a minimum you want a the end to be rolled over atleast 120deg+ to get the full flow potential from a *free to air trumpet* unless its encloesd then you have 2 choices.

1 roll the trumpet into the plenum floor (as per RMS' pic)
2 have the trumpet protrude thru the floor but keep the end of the rollover a minimum of 15mm off the floor of the plenum.

i use the first option if im doing a short runner manifold (more for high boost applications on topend style motors)

and the second option for small displacement motors that need every bit of runner length they can get.

cheers
linden

[The Real Roadrunner]

to answer the first post why not get that inlet and mod it to suit your needs.

ie buy it, cut the plenum off finish the inside of it properly then weld the plenum back on in the reverse direction and straighten up the inlet (or turn it the direction you need.

cheers
linden

[roadsailing]

http://www.jenvey.co.uk/drawings/AH_Straight.gif

http://www.jenvey.co.uk/

have a look at this site, interesting reading, though it seems to be aimed more at NA that forced.

from what i have been reading, you will get different results from different shapes, so it really pays to experiment.

again, for a turbo i'd blend it into the bottom, as it just seems the way most of them are done!

[Bazooka]

Yeah I know there are better versions out there than what I posted. That was just an example. I have seen others for RB25 and 1JZ/2JZ that look the goods. If I can get something off the shelf than it saves me a hell of a lot of customising if I have to chop something up.

[Ben Wilson]

to answer the first post why not get that inlet and mod it to suit your needs.

ie buy it, cut the plenum off finish the inside of it properly then weld the plenum back on in the reverse direction and straighten up the inlet (or turn it the direction you need.

Couldn't you just turn it up side down? IIRC, the 20v trumpets have the bolt holes evenly spaced top and bottom......

[The Real Roadrunner]

Couldn't you just turn it up side down? IIRC, the 20v trumpets have the bolt holes evenly spaced top and bottom......

depends on there casting and if it would interfere with the idle screws (pretty sure they're at the top but its been a while) but the inside was nasty also so you may as well clean it up properly anyway.then weld it back up the direction you want it.

i know its not that easy if you dont have the equipment, but it would only be $100 or so to weld it all back up and then you know it the way you want it internally.

20v's want the longest trumpet length you can give them so id leave them the same length (no actually id put some nice ones in but thats me) just have them nice and smooth.

cheers
linden

[Ben Wilson]

depends on there casting and if it would interfere with the idle screws

The flange on the thing looks symmetrical...