Candoo & Candoo II Exhaust (spare mounting underbody)

Brainstorm - Candoo IV

[3/24/2002] Reviewed by: John Perodeau -

Applicable to: '90 - '97 1.8 liter

Candoo IV exhaust, allows relocating spare tire to beneath car, creating more trunk room.

Excellent. Very quiet compared to earlier Candoo's (II and III). Everything lined up correctly, didn't have to bend any hangers to eliminate rattles. See the earlier Candoo description for info on installation. I did mine in the driveway, with jackstands under the car.

I bought a Candoo II some years ago because I was on a 3-month out-of-town project, and needed the trunk room. It was noisy, especially resonant around 3000 RPM. Bought the Candoo III after trying some home-made mods to the II. bouth the IV just last week, solely because it was advertised as quieter. It is!. Makes the car much more pleasant to drive. Painted flat black, unlike earlier Candoo III that was all stainless. There was an early odor, as the paint burned (I assume - haven't been under the car to check), but it is no longer there. I recommend getting a new cat-to-midpipe gasket before starting. If you asked Brainstorm politely, maybe they would include an extra gasket. They're nice to deal with.

Over 30 minutes to remove completely

Candoo II Free Flow Exhaust and Spare Tire Relocator

Reviewed by: Dennis Wierzbicki -

A catback exhaust system designed to allow increased performance, more aggressive sound and relocation of the spare tire underneath the car. The old Candoo exhaust systems came in three flavors: The Quiet, The Loud and The Resonator (sounds like either a Spaghetti Western or a movie starring Aahnohld). Last year, the company making these systems went out of business, and Brainstorm Products took the product over. Today, The Quiet and The Loud are history, and BSP is marketing a version of The Resonator known as the Candoo II. I’ll describe the installation in my ’95 (12,800 miles) as well as several omissions and errors which were in the instructions.

Step 1: I put my ’95 up on jack stands the night before and sprayed all the nuts and bolts on the existing system with penetrating oil. The following morning, I sprayed them again about 15 minutes prior to starting work.

Step 2: Take the spare tire out of the trunk and set aside.

Step 3: Remove the 14mm nuts off the rear end of the catalytic converter (if you’re gonna have trouble during this whole process, this is where it’ll be - mine came off very easily, maybe because I let the penetrating oil set on them all night, or maybe because I only have 12,800 miles on the car!). Leave the gasket in place. BSP’s instructions call for removing this gasket, but unless you received two gaskets with your installation kit (I didn’t), you’ll need to re-use the existing gasket. Do not remove the catalytic converter!

Step 4: Remove the tailpipe/muffler assembly from the back of the converter and from the rubber hangers (BSP’s suggestion to use liquid soap on the holes in the rubber hangers here is a great idea - it really made removing the tailpipe/muffler a lot easier). The assembly should be resting on the frame brace assembly (on my ’95, a U-shaped combination of three black tubular steel, flattened at six points to allow six bolt holes to be drilled - I can’t speak for what this assembly looks like on other model years, or even if it exist at all on some of the older Miata’s).

Step 5: Remove the six bolts holding the frame brace in place. Be aware that as soon as the last bolt is removed, the brace AND the tailpipe/muffler will come crashing down - be prepared to catch it!

Step 6: Remove the heat shield, a thin gray metal plate mounted under the trunk. Re-install the bolts into the bottom of the trunk after removal of the heat shield.

Step 7: Install a new muffler hanger on the cross brace per BSP instructions. I used an open end wrench on the top nut, and a socket on the bottom. Make sure the bracket is aligned with the transverse structural member onto which you are mounting it.

Step 8: Remove the carpet from the trunk (a claw hammer or "wonder-bar" really helps here, but be prepared to break a couple snaps anyway), and take out the left side rubber plug on the floor of the trunk. Install the spare tire hanger from the trunk through this hole. BSP instructions talk about an arrow to orient you on which direction is the front of the bracket, but there was no arrow on my hanger. After a phone call to BSP, we jointly determined that the bolt attached to the plate of the hanger, which is intentionally set at an angle, should have the angle pointed towards the front of the car (VERY IMPORTANT that you get this right, otherwise the spare tire will NOT fit under the car!). Push the plate as far forward as you can, then drill two inch holes through the holes in the plate portion of the bracket and through the floor of the trunk.

Step 9: Attach the spare tire hanger using two 6mm bolts, nuts and washers. BSP instructions say you might need to get a helper to hold the bolts while you tighten the nuts from below, but I was able to reach around the bumper and do this job myself.

Step 10: I sprayed the nuts and washers which were attached in step 9 with rubber undercoating from the bottom of the car, to seal and rustproof this new penetration into the car.

Step 11: Assemble the new tailpipe to the new muffler assembly. How these two pieces fit together is not obvious. I found it easiest to lay the two new pieces on the floor of my garage under the car and visualize their location once installed. Once you’ve figured this out, take your one (in my case) new gasket, and assemble the two pieces together.

Step 12: If you removed the gasket from the converter earlier, either reinstall the old one, or, if you got two with your kit, put a new one on before mating the converter with the tailpipe/muffler. Here’s where I ran into my only problem of this whole installation: lift the new tailpipe/muffler assembly into place, slide the flange at the front of this assembly onto the bolts at the back of the catalytic converter (when I did this, the holes on the flange did not line up properly with the bolts on the back of the catalytic converter. I had to drill the holes out a little and file them oblong in order to get it all to fit together). Once you’ve gotten the flange and bolt holes to line up, put the nuts on the converter bolts, but DO NOT TIGHTEN THEM.

Step 13: Beginning in the rear, attach the rubber hangers to the posts on the tailpipe/muffler assembly. When you get to the place where the new hanger was mounted to the transverse structural member, you’ll need to take the rubber hanger which is no longer needed (the one just behind of the new one) and transfer it to the new hanger. Work your way forward, attaching all four rubber hangers (BSP instructions say there are five - there aren’t).

Step 14: Now you can tighten the nuts between the catalytic converter and the tailpipe/muffler.

Step 15: Reattach the frame brace.

Step 16: Install the spare tire from underneath the car, onto the spare tire hanger bolt, using the 12mm nut and large 12mm washer. The bracket’s bolt will go through one of the lug holes on the spare. This will take a little wiggling and pushing, but it IS possible. Get this nice and tight.

Step 17:Ensure the tailpipe is not touching the rear bumper. The pipe itself is large, and fills up the original hole. If your alignment is off on your installation, you may have to adjust to not have the tailpipe touch the bumper. I had no problem with this, however.

Step 18:Reinstall the carpet in the trunk.

Step 19: Lower the car and that’s it! Don’t forget to pack a inch socket/ratchet or wrench in with your tools, otherwise you’ll not be able to take the spare off if you need it.

Total installation time, from taking the old system off to putting the new one on, including drilling out the holes on the flange, was just over two hours. In use, the system has a very low growl, and is noticeably louder than the stock system. Having not heard the "The Loud" system people have spoken of, I can’t compare the Candoo II to this well known system. It is not too loud to be objectionable (although my girlfriend prefers the stock sound), and I feel the tone is a very smooth, low roar, with a nice burble on downshifts. Definitely a better sound than a Borla, which is too raspy for my tastes. AND, it’s cool to be able to reclaim a chunk of space from the trunk! The tailpipe is a shiny silver, and as mentioned earlier, fills up the hole in the bumper nicely. All in all, a well designed and executed system. I recommend it to anyone looking for a more aggressive sound. Any performance gains are hard to determine, although my engine seems to rev freer (might just be my imagination coupled with the new sound).

Reviewed by: Douglas Clark -

High performance exhuast that includes moving spare to under the trunk. The spare just fits in the area under the trunk. This really increases the usable area in the trunk. Makes the trunk a real carry anything kind of vehicle.

The kit was easy to install and came with complete instructions-also included was a new muffler hanger bracket that installed in a stock frame opening. But how does it sound? Since this is the "High Flow" model it does not have a second resonator to deaden the sound it is quite loud. The "High Flow Premium" model includes the second resonator. At first I thought it was *really* loud! and was considering order the second resonator.

But after a couple of weeks driving it has grown on me and I really like the deep growl on acceleration and the pleasant burble on shifts. The car (a '95 M) seems to rev freerer and is a little faster on highway passes. Now every time I approach an overpass I drop a gear to hear it sing. Unit was under $300 dollars from a local South Florida Miata house. (Lloyd Wolf's Miata World) Also availble direct from Candoo. Increasing your trunk space is a pleasent side effect of having a killer exhaust sound.

Candoo Exhaust

Reviewed by: Jim Whalen -

Kit to mount spare tire under car. Includes catback Hi Flow exhaust system with resonator.

Product is well made and easy to install. Came with all fittings and parts. Hi Flow resonator model is only slightly louder than stock muffler. Perhaps a small increase in performance but not the reason I bought the product. Installed on a 1992 Miata. Installation requires removing the stock exhaust system from the catalytic converter back. System routing allows room for spare tire under car. Exhaust tip is in stock location on passenger side of car. Mounts on original stock hangers and one new hanger. Trunk space is greatly increased. I can now get two golf bags in the trunk (I bought some very small Jones Sport golf bags for about $75 each.) Ordered exhaust system directly from Candoo. Cost was about $350 delivered. Ordered in May 1996. Delivery took about three weeks. Only minor problem was installing spare under the car. The tire hits the rear bumper making it difficult to slip the wheel onto the mounting stud.

Installation time was about seven hours. You can do it in less time. I did this over about three days so I had some start and stop time. It also took some time to jack the car up and mount on jack stands and then dismount. Be very careful in removing the nuts holding the stock exhaust to the catalytic converter. It is very easy to round off the nuts. Try an open end wrench rather than a socket wrench for best results. I am very pleased and consider this a quality product.

Back to Product Reviews 20 April, 2002