Type 4 Exhausts

Intro | Exhaust Ports | Pancake | Upright | Type 3 | 914/912/912E | Custom Made

This page was last updated Friday, May 18, 2007

Upright Cooling

Most of the people that are reading this site are interested in converting a Type 4 engine into an upright engine. So, with that conversion, a custom exhaust is required.

    Street: This is probably the most popular application at the moment. There are many people who are looking to install a Type 4 into their street Bug (like me) and they want to know what they can use to finish the installation.

Chris Stanford modified a stock Type 4 muffler and heater boxes for his stock 2.0 powered '74 KG convertible.

Our first look at upright street exhaust systems lies with a very simple system that mimics the stock setup. These systems generally consist of either stock heater boxes or j-tubes, along with a shared muffler. These systems are popular in Europe, as they are usually more economical than a tube header.

The first system we'll look at uses a modified stock 411/412 muffler (the original ones need to be shortened, as they are almost as wide as a Bug) and shortened 411/412 heater boxes. It is necessary to shorten the heater boxes else the muffler will stick out from the body, kind of like another bumper. From a performance stand point this isn't the best choice, but if money is tight and you have the necessary skills, it does work.

Many of the European tuners offer a muffler similar to this that bolts on to shortened heater boxes for sound control.

British LA Performance, and German firms Klaus Kaefer Tuning, and CSP all sell muffler systems similar to what I described above. The beauty of these systems is the simplicity of installation, maximum ground clearance, and stock appearance. They are also economically priced, as they don't require expensive tubing benders to produce.

These systems may not be the best for a performance engine, but they work fine on a near stock engine that isn't asked to work hard. So if you are looking to convert that stock 1.7 to upright cooling and aren't worried about racing the Honda down the street, this option maybe your choice.

Eddie Brown followed the Cali method for his 1911cc Type 4. What's unique about his system is the muffler placement, behind the rear apron.

For most mild upright conversions, a very cost-effective exhaust system is to use the stock Type 4 heater boxes and a header meant for the Bus. The heater boxes will have to be shortened though, as they will place the header/muffler too far out and interfere with the rear apron. The most common heater box used for this conversion is the dual port used on the early Type 4s. Joe Cali of Next Generation details this conversion in his book.

TriMil produces what is commonly known at the "FAT" header. This system is an economical choice for stock or near stock upright street conversions.

For those engines that need more flow than out of a standard Bus header, there are alternatives. The first alternative is available from FAT Performance. Their ES731 exhaust system includes head pipes, a header, and dual quiet pack mufflers. This system is also available from any TriMil dealer, so if your local VW shop carries TriMil, inquire with them on the cost of this header. When installed in a Bug, it looks real similar to a header on a Type 1 engine.

Some people have complained about the quality of the fit of this exhaust, but others have praised it. I have also recently learned that TriMil was purchased by another company, AC Industries. My source there tells me that some of the sealing issues at the headpipes can be fixed with their 3/8" laser cut flanges. I hope that AC Industries is willing to invest some time and money into their Type 4 prodcuts of the TriMil line, as their products could fill a need for moderate priced exhaust systems that the Type 4 community has been needed to fill.

Tangerine's SuperHeader is a complex system, but dyno runs have shown it produces the most across the board power.

The Tangerine SuperHeader for a Bug is a great choice if you are looking for a wide range of power. This system is well suited for the German Look sedan, as its broad power band and high mounting makes it a natural for cornering. This header is available with optional "silencers", QuietCan and Phase9, to quiet the exhaust note, but they are placed up high so that you don't need to worry about scraping the exhaust in a dip.

The Tangerine SuperHeader is a 4-2-1 design and has consistently done well in dyno pulls. Each header is custom assembled for the customer, so most modifications are easily accomodated. This header is available in 1⅝" and 1¾" tubing and is available with optional heat exchangers. That way you can have the big power of that cc monster and still have heat in the front seat.

Tangerine Evo system for Type 4 powered Beetle. Note that this system exits through stock exhaust holes in apron.

A new addition to the Tangerine Racing line of exhaust systems for the Type 4 engine is their Evo header. This is what Chris Foley, proprietor of Tangerine Racing has to say about this new exhaust system:

A breakthrough in collector design allows shorter and more precise pipe lengths without crossing under the sump. These headers feature the same 4-2-1 design as the original Super Header, but with an improved layout and enhanced performance! The Silencers exit from the stock valence cutouts.

The shorter primary tubes on the Evo make it suitable for the more mild Type 4 conversions. This system also clears the sump, so you can add an external deep sump for increased oil capacity at the pickup tube.

This is the ultimate setup for those of you looking to build a stock sleeper. Imagine a stock height Bug with no modifications except a nice Type 4 and this exhaust. Everyone's jaw would drop on the freeway as you merge into traffic without breaking into a sweat.

A-1 brings a traditional VW merged header to the Type 4 conversion. Dyno results have shown it produces the most peak hp.

In the tradition of the Type 1 merged header, the A-1 Performance merged header is currently the king of the hill when it comes to horsepower. Jake Raby and myself played a hand in getting this header designed, fulfilling a need for a traditional header for the Type 4 conversion. This header, available in 1⅝" or 1¾", uses any of A-1 "Phat Boy" style mufflers. Unless your engine displaces over 2500cc's or is designed to live at 8,000 rpm, the 1⅝" with a 2½" Magnaflow muffler is going to get you the most power out of your engine.

When installed with one of A-1's mufflers, from the outside the exhaust looks just like a merged header on a Type 1 engine. This is great for those of you like myself who like the traditional Cal-Look, but who also want the benefits of the Type 4 engine. Of course, care must be taken when driving with such as system, but I've done it for years and never had a problem. This header also makes adjusting valves easy and keeps the heat from underneath the body.

Ron "Plastermaster" Roberts commissioned A-1 to make a Sidewinder for his 2270cc Type 4 powered 1973 Karmann Ghia coupe.

The first half of 2005 brought another exhaust header from A-1 Performance. This time Jake Raby of Aircooled Technology enlisted A-1 to develop a Type 4 version of A-1's Sidewinder exhaust system. The first system was developed for Ron "Plastermaster" Robert's 2270cc Type 4 powered 1973 Karmann Ghia coupe. You can see from the photos that this system places the muffler high into the body and maintains good ground clearance.

This system, ideally suited for German Look sedans and daily drivers, diversifies the options available from A-1. This system would also work great for those that are building street versions of Class 11 racers, as the high muffler placement allows for a skid plate to protect the engine and exhaust.

The downside with the Sidewinder, according to A-1, is that the muffler selection is limited to a couple of 2½" mufflers and to the 1⅝" tubing. For most Type 4 conversions, that is the best size, but if you must have a big cc bruiser or a high spinning sprinter, then the standard A-1 header is your best option, as it has more high-flow options.

If you live on the other side of the Atlantic, you have many choices too. There are exhaust manufacturers from mainly England and Germany. I can only speak from what I've heard about these systems, as I only have seen (actually own) one exhaust header from an European manufacturer. If you are on this side of the Atlantic and want an European system, make sure you take in account the current exchange rate of currency and for the shipping.

Germany's BAS Ahnendorp offers many different systems, like this one. The ground clearance of this system is great for road racers and anyone else concerned with bottoming out their car.

Probably the most well known of the European suppliers is BAS Ahnendorp of Germany. They have a large selection of exhaust systems in different sizes and materials. BAS has been manufacturing exhaust systems for the Type 4 for a long time and their products are well received in Europe. These systems are very popular with the German Look Bug owners, as they mount up high and provide ample ground clearance.

Until the A-1 header became available, the BAS headers were the most common pre-made system used by American Type 4 owners. I purchased a BAS # 21152 header, but elected not to purchase the mufflers, as I was going to have a muffler fabricated similar in style to the later released Sidewinder muffler. Although I'm now going to run an A-1 (since my car is a Cal-Look car, the A-1 looks better with it), I'm going to keep the BAS header around for a future build. This header cost me just over $400 to purchase and ship to southern California.

UK's Turbo Thomas offers this header with many different muffler options. Stub tubes are available for both exhaust port styles.

For those of you in the UK, you have two excellent manufacturers to turn to. The first is Turbo Thomas. Turbo Thomas sells a nice 4-1 header that utilizes their muffler setups. They are also willing to modify their designs to suit your needs, so Turbo Thomas is definitely a company to check out.

One of the unique features of the Turbo Thomas header is that they offer at least four different types of mufflers to complement their header. Thes include a single quiet pack(QP) type muffler, dual QP (like you see on a lot of Type 1 engines), a large turbo style muffler (2½" and 3"), and a "road racer dual muffler system". The latter muffler setup is for those that need any ground clearance they can get.

LA Performance offers many different systems, including this dual turbo muffler header.

The next British company is LA Performance. Lee Arnold, the LA of LA Performance, has developed a couple of different header designs for the upright Type 4 conversion. They even have a dual turbo muffler setup that may do well with a more high performance engine. LA's header shown on their green 1303 (curved windshield Super Beetle) appears to be a great system, though the ground clearance is going to be an issue for most. It also doesn't clear a deep oil sump, so keep that in mind.

Just a note: BAS Ahnendorp also offers an exhaust system for installing a Wasserboxer engine into a Bug.

TriMil has long been the first name in offroad headers.

    Offroad: In this category, we start off with an obvious choice: the excellent TriMil 4 into1 header. This exhaust utilizes 1⅝" tubing and includes it's own head pipes. They are extremely popular with the desert racers and FAT Performance even sells one that uses 1¾" tubing. Be warned though: this exhaust is loud. Its pipe exits upward, at about ear level. I'd prefer to install a free flowing turbo muffler to make it easier on the ears. To minimize the sound, I suggest that you invest in their u-bend collector, or attach a muffler to the end of the system. I've experienced TriMil headers on Type 1s with a turbo muffler, and the car was reasonably quiet,

Another option in development is coming from A-1 Performance of Santa Ana, CA. Jake Raby has again commissioned A-1 to build him a well performing system, this time an off road header. There isn't much more information to report at this time, but as soon as it is available, I will make the update here.

This unique offroad system is available from BAS of Germany. It features twin silencers and is available in stainless steel for long life.

For those of you on the other side of the Atlantic, BAS Ahnendorp offers their "Trike and buggy exhaust system" that looks pretty nice. It has stainless steel tubing for a long life with dual silencers.

Although this system isn't the cheapest system available, it's unique design makes it well suited for street going open bay vehicles, like Baja Bugs and fiberglass dune buggys. This system is one to consider if you live in a state that requires the exhaust system in your buggy to be protected under a cover. Using a fiberglass cover from the body, you can make holes in the cover for this system's exhaust tips.

Thanks go to Rolf Christensen, Ron "Plastermaster" Roberts, Ephraim "Ephry73" Castillo, Rich Craig, Tom "Tom Notch" Hansen, and Jake Raby for all of their help in gathering the information and supplying photos. Thanks guys!!