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74K views 402 replies 52 participants last post by  mukle 
#1 ·
Do we really need them?
This is the question that I am researching right now.

Turbo or Supercharged piston engines typically use many cylinders arranged in-line and one or two superchargers. Superchargers deliver air at a relatively constant rate, while cylinders demand it in a varying manner, as the valves open and as piston speed varies through the stroke. Simple direct ducting would give problems where the nearest cylinders received more airflow. The pulsating demand from the cylinders would also show problems of either pressure waves in the duct, or a shortage of inlet air towards the end of the inlet phase.

The solution is to provide a large-volume plenum chamber between the inlet and the cylinders. This has two benefits: it evens out the difference in path restriction between cylinders (distribution across space), secondly it provides a large-volume buffer against pressure changes (distribution over time
 
#210 ·
That's the answer I got from KMS while I sent V-Rod stock IAT curve to them.

"Our sensor has similar resistance.
Official it is NTC +/- 2,2 kOhm at 20-25degree"
 
#212 ·
I will use a aluminum washer as a gasket.
I do not have extra IAT pieces, our local KMS importer have them in their stock.

A Modified KMS 3bar MAP in a stock location is a great deal as well (1487cc turbo topic, post #28)
 
#213 ·
We have been thinking with Mukle, what kind would be a good universal plenum for V-Rod.
Here it is.

The plenum is possible to use right or left side feeded.
A charge tupe can be fitted every 45deg position.
Volume of the plenum is about 2000cc.
Multi purpose flange, which we will machine on Saturday, is used with the plenum.

Comments, some other ideas?

 
#248 ·
Are you still doing this one?
 
#214 ·
Karzza
If you have separate chambers for front/rear cyls. will it have any benefit over this design?

Sent from my SPH-L710 using Motorcycle.com App
 
#215 ·
At least a volume of chambers should be relatively high, I think something like 2*1500cc
 
#216 ·
Thats what I am talking about.

Very Nice Sir.

Just need to make sure that there are fluts on the adapter at least .500 of an inch high.
This will help with the air flow.

Add ports for the boost gauge/ regulator / wastegate/ 2 bar sensor / ect...
 
#218 ·
What about putting the nozzel where the boost air splits so that you get more atomization?
 
#219 ·
The next version, here you are.

All the needed connections (1/8"NPT) are located to the flange. A plugged BOV-location is possible to utilize for measure-purposes.

Mukle is checking if 280mm total lenght woud be possible w/o hitting to an airbox cover. More lenght would help airflow near and around of the velocity stacks.

Personally I believe a linear airflow is the best in a plenium and in runners. (Target is to turbulece fuelled air flow into a cylinder after passing a valve plate)


rsc, can You explain "Just need to make sure that there are fluts on the adapter at least .500 of an inch high" in other words.




More ideas and comments are wellcome to design the best plenum for everyone.
 
#249 ·
I mean , this one!!!

:D
 
#221 ·
Bottom right small picture has 2 black volecity stacks.

Can you please tell me how they are incorporated into the plenum.

Are they seperate from everything else?
 
#222 ·
The plenum is sligtly re-shaped and the volume is now 2300cc.
Also an airflow aroud of velocity stacks is better at the moment.

A Volume of a 50cm 2" charge tube is 870cc, so a packet w/o a cooler would be 3170cc.
1130cc it means 2.8x engine displacement
1250cc it means 2.5x engine displacement

Should be pretty good.
We will machine the 9pcs of flanges tomorrow...and my new 60 trim compressor housing.
I will sent a picture.

 
#223 ·
Karzza, Since you are going all out, may i suggest a pair of injector nozzle ports as an option on the top of the housing ? It will require a different ECU, but would allow for a "shower head" injector system that would run smaller injectors at part throttle and second set to come on with boost. More efficient than one big set. I like the air horns & modified inlet, but still think 2 1/2" might be considered.
 
#226 ·
#224 ·
Excellent Work!!!

This is better then the Last one.
 
#227 ·
We spend a 13 hours long maghining day, here is an output.
I will purchase o-rings, screws, washers, IATs+sockets etc. in beginning of January, when I'm back in business.

(Moderator can convert the pictures to thumbnails)

The first test, does it fit...



A Ready one



 
#229 ·
:them: :notworth::notworth:
 
#234 ·
Karzza,
I agree with Greg on this one.

If you are going this far,

Just turn it into the Throttle Body and be done with it.
 
#236 ·
Go Practice Fabster...
 
#238 ·
I needed to clock the outlet on my turbo & noticed I had about a 1/8" mismatch for close to 1/2 of the turbo to the outlet tube. I cleaned that up an polished out the inside as far as my sanding roll could reach. It was a kit on Ebay from Standard Abrasives for something like $28 shipped. Hope you can see the improvement in the pictures.
 

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