30 replies to this topic

[Steam]

Dsn classics do one.

[Ol timer]

Hi all, In my experience, drilling holes to the bottom hasn't noticeably increased performance on a stock 998. Instead I machined up a ram pipe that fits over the opening to the airbox. The design is based on the optimum ram pipe airflow geometry which pulls in air from 360 degrees including from behind the opening. Above all else it tidies up the airbox and makes it look less incomplete with the steel flappy paddle intake missing.

Any chance of seeing a photo of your ram pipe setup

What is your email address? I'm struggling to add images to this vintage forum interface haha.

kberlyn@prodarts.com.au

[sonikk4]

Hi all, In my experience, drilling holes to the bottom hasn't noticeably increased performance on a stock 998. Instead I machined up a ram pipe that fits over the opening to the airbox. The design is based on the optimum ram pipe airflow geometry which pulls in air from 360 degrees including from behind the opening. Above all else it tidies up the airbox and makes it look less incomplete with the steel flappy paddle intake missing.

Any chance of seeing a photo of your ram pipe setup

What is your email address? I'm struggling to add images to this vintage forum interface haha.

Trying using Imgur, it’s free to use and easy to set up.

[stuart bowes]

https://imgbb.com/ is free and requires no set up

 

you just drag/drop your image onto the first page, choose 'don't delete' and then choose 'full image BB linked' which produces a code you copy and paste into your comment

 

picture added job done

[beardylondon]

Ive got the DSN classic one, as I also wanted to tidy up the opening

 

https://www.dsnclass...if-carb-airbox/

 

 

Edited by beardylondon, 28 May 2022 - 01:20 PM.

[Maccmike8]

[D 'n A]

It’s a no brainer, I use this example when I deliver my su training to dyno operators, drilled airbox is better in every case and the bigger the engine it’s fitted to the more it’s needs drilling.

Ac

A.C. I have this mainstream Cooper airbox. I currently run it without a snorkel. The inlet is large enough. Is this a good idea or would it be better to put the snorkel back on and drill holes to achieve higher airspeed at the airbox entrance?

Edited by D 'n A, 30 May 2022 - 07:46 PM.

[h9hpj]

Thanks for your comments - air box drilled and k&n filter installed. Sounds lovely now without the drone from the old cone filter. 

[ACDodd]

In answer to D n A that filter will be fine put to around 80hp ish, you may be throwing a lbft or two away below 2500rpm without the snorkel on , but don’t fit the pipe which goes ar cross the rocker cover that’s restrictive even at 65hp.

Ac

[GT Jimmy]

Very helpful info here, I'm going back to the original airbox and was looking for info on drilling the airbox. Cheers

[GT Jimmy]

It’s a no brainer, I use this example when I deliver my su training to dyno operators, drilled airbox is better in every case and the bigger the engine it’s fitted to the more it’s needs drilling.

Ac

Hiya AC, my engine is a 1310 with an Evo 1 cam, hif44 on a Howley inlet with a cone filter. Will be swapping to the original airbox with a k+n filter.

My question is, should I jump straight in and drill the 6 holes or maybe do 3 or 4 then see how it goes, cheers, Jimmy

[ACDodd]

Drill lots.

Ac

[GT Jimmy]

Cheers AC. I'll do the six

[ACDodd]

Drill more than six, drill the periphery 3/4” holes around 2/3’s of the circumference of the airfilter.

Ac

[GT Jimmy]

Thanks for the advice, I'll book rolling road session then fit it when I turn up