Cappuccino In Line to Autocross

Project Cappuccino: A Wee Bit O’ Power

Project Cappuccino is wonderful: The combination of light, well-balanced chassis, responsive turbocharged engine, and inoffensive body with convertible roof make for the ultimate toy.  It’s an incredibly fun car and unlike most ultra-light sports cars, has a roof, doors, heat, and even a real trunk.  It’s a wonderful autocross car, but there is a problem: we typically run with Miatas and CRXs.  A CRX was rated at 106 hp and early NA Miatas came with 116.  The Cappuccino started life with a paltry 63 hp.  Even these lowly sportscars are making nearly double what the Cappuccino did and the Cappuccino only has a 400 lb weight advantage.  A bit of extra power would therefore be very helpful in helping us close up on our competition.  The easiest way of finding power in a turbocharged car is to reduce backpressure and suction losses, so we decided to look into ways of uncorking our intake and exhaust systems.

Suzuki Cappuccino Engine Bay
Our Cappuccino already has a Suzuki Sport intake installed. This intake replaces the factory airbox with a cone filter. However this kit is fairly old and the rubber couplers of the filter were starting to dry rot. The filter is also too big and doesn’t really fit in the space between the engine and the core support You can see here that it contacts both the hot pipe and the core support. It’s a standard-sized filter but is too big for the Cappuccino. Yes, this car is friggin tiny…
Suzuki Sport Filter vs. K&N Filter
Rather than completely replace the intake, we decided to refurbish it. First, we replaced the air filter with a brand-new K&N filter. This filter is about an inch smaller in length. Both filters are the same diameter at the tip, but the K&N filter is straight while the Suzuki Sport filter tapers out. Without the taper, the K&N filter better fits in the engine bay. This will be a much better fit in our engine bay. We’re not concerned with creating any sort of intake restriction since even this smaller filter has over twice the surface area of the original Suzuki panel filter.
Suzuki Sport Air Filter Adapter
We are keeping the hard anodized air filter adapter. This adapter connects the large 3” filter down to the 1 ¾” inlet tube. It’s a nicely machined piece of billet aluminum with a smooth transition as it necks down.
HPS Intake Tube & Suzuki Cappuccino Intake Tube
The Suzuki Sport intake uses the original intake tube. It’s not a bad part, but it’s thin plastic and the flex joint creates turbulence, which effectively narrows the size of the tube. It also makes the intake look half-assed when there’s a beautifully machined adapter connected to it. We decided to replace the intake tube with a 90° 1 ¾” diameter elbow from HPS. This elbow is made to handle boost with 4-ply construction so it won’t collapse when the turbo sucks air through it. We went with a blue hose as we’re starting to get a colored theme going with our various Suzuki Sport, Cusco, NGK, and GReddy (knockoff) parts in the engine bay.
Upgraded Suzuki Sport Cappuccino Intake Installed
The elbow comes with 5” legs. The original intake tube is 4” from the filter to the bend and 3” from the bend to the turbo inlet. We just sliced off the appropriate lengths and the HPS hose was a perfect fit, completing our improved intake system. For those starting from scratch, Monster Sport sells an updated version of the Suzuki Sport kit (which now includes a heat shield) as well as a premade intake tube.
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7 comments

    1. Thank you! I’ve been enjoying learning all about this platform and I’m glad folks enjoy what I’ve put together.

      Reply

  3. Awesome. 3 cyl motors sound a lot like straight 6’s the same way the inline 5s of RS3 and TTRS sound like their 10 cyl big brothers.

    Reply

  4. Duralast? Yuck. I wouldn’t count on any longevity out of that coil. Parts store brand stuff is awful quality in my experience unless something has recently changed. Looks like NGK and Delphi still supply coils for a 98 Metro for under $50. I’d go with one of those.

    Reply

  5. I love coming back to this series while working on my Cappy. Just finished swapping the timing belt (and all of the “while you’re in there” seals. It sounds soo good without the airbox, I immediately started looking for a good source on DIY intakes.

    Thanks for the tip on HPS hoses!

    Reply

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