engine and drivetrain Custom Dual Carb Air Cleaner.

[jdeitch]

As part of my dual carb conversion I needed air cleaners. I wanted to use velocity stacks too. With the limited space considering my non-tii brake booster this was a challenge. I found several air cleaners that would fit but that we're not large enough to allow the use of 40mm velocity stacks. I wanted my cake and to eat it too. Simple solution... Make my own.

40mm velocity stacks.. 2.5" wide air filters.

I made this out of an old sign. Thin gauge sheet metal. Work in progress. Much to my dismay it DOES contact the brake booster. I will MAKE it fit.

It's hard to tell from the pics but the bottom has the same hole pattern as the cover. Each side also has a air inlet hole.

Trim the cover tabs. Bead blast. Powder coat. Almost done.

Edited September 29, 2013 by jdeitch

[73touring]

Seeing as your at it would you design in a cold air feed like a ti air box?

[Simeon]

That is nice work.

Why is this arrangement better than the same filters with simple sandwich plates either side? The lid would still be the same distance from the ends of the ram pipes

[M3M3M3]

+1

well done, and love the old sign material.  if not bringing outside air in, why not just use sock filters?

 

Edited September 29, 2013 by mlytle

[TobyB]

What you'll find is that you'll need to retune for having that flat plate in front of the trumpets.

 

The DCOE is noticeably suceptable to mixture variation based on what's in front of the stack- like, up

to 2 diameters, at least.

 

When I got my race car from Mike, he'd fabbed up something like you have.  He'd tuned it for a 

(limited prep) setup, and it worked great.

However, when I opened up chokes, header, etc the carbs really didn't like his intake.

I played with a few that REALLY killed horsepower, and finally settled on something that

gave as much room between the trumpet mouth and the filter as possible, and let air come in 

'more or less' straight at the mouth.  

 

It's still not quite as good as no airbox at all, but it does the least harm I could manage and still get clean air in.

 

t

Edited September 29, 2013 by TobyB

[Rocan]

best thing would be a big sealed airbox, tuned to the RPM you want peak torque at, with as little shrouding between the stacks and box as possible. Also it will allow you to take air from a cooler place. Open V-stacks (without any filter) make peak power, but a proper sealed box will give you the best overall powerband without very much top end loss. Also open V-stacks can be a pain to tune. Luckily engine bays are pretty closed off from airflow, but if you ever try tuning open stacks on a motorcycle, you will know the trouble that even a slight breeze across the carb mouth can cause. 

[jdeitch]

Metalwork complete.

High temp, fuel, flame proof semi gloss black paint inside and on tabs. Black wrinkle finish paint on outside.

[jdeitch]

Completed. Installed with new air cleaners. I like the E30 M3 look.