While building up my new (to me) S52 supercharged engine for my E36, I had to decide what to do with the exhaust coming out of the head. Throwing a wrinkle in the plans is that I need to keep my stock catalytic converter pipe in place to pass my local county emissions (I was able to get my supercharged M50 to pass without issue).
I basically had three main choices:
- Use stock S52/M52 or M50 exhaust manifolds. S52/M52 manifolds are tubular in design and save a little weight over the cast iron M50 manifolds. But all the stock manifolds aren’t equal length and restrict flow in the mid-range and top-end. And they certainly aren’t aesthetically pleasing!
- Use “long tube” style headers that are readily available from multiple sources. They flow the best at top-end but could lose a little in mid-range. However, my concern about using these isn’t in power delivery, it’s in mating up to my stock catalytic converter pipe. I would need to modify my pipe in order to make these work and I don’t want to do that for a few other reasons that I won’t go into.
- Use “shorty” style headers that make good mid-range torque, sacrifice a little top-end power compared to long tube headers, but bolt directly to my catalytic converter pipe.
So, as you can see from the title of this post, I decided on shorty headers. And after a good bit of research, I narrowed it down specifically to the shorty headers from Turner Motorsport. They appeared to be high quality items, designed and produced by a company who’s seen a lot of success in racing BMW vehicles with their own products equipped.
Turner Motorsport provides a great description of their shorty headers on their website:
“A Turner Motorsport developed part, our “shorty style” performance headers are CAD designed to be equal length and flow with equal pressure, made from 100% stainless steel, and finished in a 2-stage ceramic coat. The layout and tube sizes were designed to increase mid range torque and power with additional increases at the top end. Bolt these on to your stock E36 or Z3 for a instant 12 ft-lb torque and a 9 HP gain – we often see more on modified engines!
Unlike other headers on the market, the TMS Shorty headers bolt directly to the stock BMW catalytic converter! Stainless steel construction retains heat much better than the mild steel often found in cheaper copies of our header. This results in increased exhaust velocity. Our headers are also TIG welded on the outside and use an ‘under-over’ construction into the merge collector so exhaust flow is not disrupted. Don’t be fooled by cheap, non stainless imitations that sell for less. Trust us – you get what you pay for. If you want the best shorty header on the market, this is the one.”
There are a few things in that Turner Motorsport header description that are keys to me:
- Equal length and flow with equal pressure (best performance from the engine)
- 100% stainless steel construction (longevity and durability)
- Finished in a 2-stage ceramic coating (longevity and durability)
- Bolt directly to the stock BMW catalytic converter (I need to be able to keep my stock cat for emissions testing)
The headers use very thick flanges that look well designed for the added stresses of racing.
Good quality welds can be seen throughout the headers to join the various sections of the stainless steel tubing.
Here you can see the three individual pipes joining in one of the merge collectors.
Pretty tricky to design the manifolds for equal length but still package them into a useable design without tight kinks.
Here’s another view of the curves in the pipes.
Thick flanges are used where the headers mount to the head as well.
The header tubes are blended very well internally with the flanges.
Test fitting them to my S52, they fit on the exhaust studs just like stock manifolds.
I actually first purchased the cheapo eBay shorty headers to take a look at their quality. Unfortunately, though they looked really nice, their fit was poor. The lower triangle flanges actually contacted the side of the block when the exhaust flanges were flush mounted to the head. To put it short, it was impossible to mount them to my S52. I’m guessing that I just got a bad one (I returned it easily) but I wasn’t that surprised.
With the added power of my S52 comes added exhaust heat which really increases the underhood temperature. To help to try to alleviate some of this, I decided to wrap my headers with Design Engineering Inc (DEI) Titanium Exhaust Wrap. Above you can see everything that I used. I purchased two of the 2″ wide x 50 ft length packages. However, I probably only used about 60 – 70 feet in the end.
There are a few different techniques that you can employ to wrap headers (I recommend searching Youtube), but, no matter what you do, remember to wear gloves! Handling fiberglass bare handed will leave lots of little glass fibers stuck in your palms like mini cactus needles.
Keeping the wraps tight to the tube with a little overlap is what you’re aiming for. It’ll definitely get tricky with some of the closeness of tubes and strange angles.
When tightening the stainless steel cable ties, I used the DEI tightening tool to pretty good effect.
Finished with one! On to the next…
Once fully wrapped, I sprayed down the header with the high temperature silicone protective spray. It effectively locks out moisture and protects the wraps from abrasion. It also helps to keep the wraps from un-winding.
I’ve heard some concerns that wrapping headers can cause them to crack. That can happen with mild steel headers but these thick stainless steel headers (that have been fully ceramically coated) should have no issues with rust or cracking.
You can see how I had to get a little creative (and less than optimal) with wrapping the header on the right above. It wasn’t ideal but the wrap is also under the bridge section on the individual tubes. It’s really tight clearances!
New head studs and exhaust manifold gasket in place on the head.
Starting the installation of the new copper nuts. As you can see this was pretty tricky with some more tight clearances. I was certainly happy to be installing these with the engine sitting on a stand and not in the car.
Some nuts could only be tightened by turn a wrench a few degrees at a time…
Done and looking great!
The silicone coating will cure with some aggressive running. You’ll definitely get a bit of smoke for your first couple drives but then you’ll be set. My wife wasn’t a fan of me curing them in my house’s oven before installation…
I’m really impressed by the quality of these Turner Motorsport shorty headers. They fit great and the stock catalytic converter pipe bolts up super easily.
I’ve now been running these on my car for about 500 miles, mostly street use, and they’re still great. The noise that they make is awesome and the wrap has really cut down on underhood temperatures. I can even leave my fingers directly on the headers for a few seconds after a really spirited run without hurting myself. Impressive!
In conclusion, I’m really impressed by the Turner Motosport shorty headers and feel like they’re a great addition to my BMW E36. Money well spent!