Velocity stacks versus K&N filters: 2500M

[Renaldo]

Guys, I have a twin Mikuni carb set-up on my 2500M

Currently, I have a K&N filter on each carb.

But I've found some very appealing velocity stacks for these carbs I'm thinking of trying.

They come with triple metal screen protection (for dust and debris) and pre-screen sock for added protection against dust.

My question is: to use the stacks, I'd need to ditch the K&Ns. Do you think the stacks offer enough protection against dust, with the screens and the sock (reputed to screen out the smallest stuff)?

Any advice or thoughts?

Ron

[Cerberus90]

If it was me, I think I'd be trying to find some stub stacks / velocity stacks to go inside the K&N filters.


I've often wondered about the triple mesh filters we've got on the twin dellortos on the 1600. With how they fit onto the trumpets, I wonder if they effectively remove any improvement from the bell curve on the trumpet as they sit on the curve.

When we tested ours on the rolling road, there was only a 5bhp difference between mesh filters on and off, I think.


Not sure I'd ever trust those sock filters, I suppose when you've got the mesh on the trumpet they at least can't get sucked into the engine,

[Renaldo]

Agreed about finding stub stacks to fit inside the K&Ns. That would be ideal.

I've checked pretty thoroughly on-line, and I don't think they're available.

This velocity stack kit looks pretty nice, and I'm hankering it only for that reason.

I'm doubting it'll add much of anything in performance, although maybe a change in sound (different breathing noises)?

My main concern is the ingress of any dirt/dust, water and so on. Although the seller assures me the kit's filtering is very effective (I should think he would say that...)

Ron

[Cerberus90]

We've been running these for a few years now, and the engine would appear to still be fine.

If you've got a sock over the top of the stacks then I'd imagine you don't need to worry too much about particulate intake.

[RCK974X]

Forgive me for being a dinosaur, but I always thought that those stacks do very very little on anything but a full race setup. Is that actually true ??

To get best performance in any car engine, you need to get the best air flow through the engine,as that is the limiting factor, and on most road engines, the valves and/or cyl head are the most restrictive part. I can see how a better free flowing air filter will help, but can't see what a stack does, apart from look pretty.

By all means tell me if I'm wrong, I'm happy to learn....

[Renaldo]

Andy, I'm sure you're probably right. Why these velocity stacks would give any significant performance improvement over high-flow K&Ns doesn't make much sense to me.

But they sure look nice. And that's why I was considering them.

My concern is too much gunk being sucked into the engine. Although I'm assured by the merchant that the filtering that comes with the stacks is very good.

Ron

[RCK974X]

Hey, "so that they look pretty" is perfectly fine, I thought from the post that you were after more bhp. No worries.

As far as I know - K&N are the best for flow plus filtering performance, but new stuff comes up all the time....