ABF Inlet manifold Modification question

[ttelracs]

This has been mentioned a couple of times regarding shortening the runners on the intake manifold.  I recently picked one up on ebay and once I cleaned out all the crud, I matched it to the lower intake manifold and smoothed the inside with a drill and flap wheel.  Once fitted, it was definitely smoother and the mpg has moved slightly.

It's got me thinking though about shortening the manifold runners radically since I now have a spare one to fiddle with.  I was thinking about reducing the length as much as possible and then reattaching the plenum end with silicon pipe and jubilee clips as a temporary solution just to run it and see how if any gains from a purely seat of the pants feel.  I know Ben S on Club GTI has tried, though not as short as I'm proposing and I've seen some American options like this.

http://www.usrallyteam.com/index.php?main_page=product_info&cPath=1_133_3&products_id=291

Before I get the angle grinder out though, can anyone dissuade me from their own experiences or knowledge. I don't want to waste half a day to bolt it on and runs like a dog as I understand the runner length can directly affect torque.

Thanks

[tshirt2k]

Going too short like 1.8T will reduce midrange torque and shifts it further up the range, which isnt good.

[ttelracs]

OK, thanks.
I'll put the angle grinder back then.

[tweed]

Cut them down so its tight on the plugs.

[tshirt2k]

Cut them down so its tight on the plugs.

Bigger plenum is also beneficial

[tweed]

Cut them down so its tight on the plugs.

Bigger plenum is also beneficial

Yes, cut 1" off the runners then add 1" to the plenum

[ttelracs]

Like the one Ben S did on Club GTI ?
I could cut down an inch, but would struggle to enlarge the plenum chamber sufficiently.  I'm going to do some research into this and see what I can get..

[tshirt2k]

Get a decent welding shop to do it.

[tweed]

My mate works at pro alloy and said its very easy to do. So as said take it to a alloy shop and they'll do it no probs