2bular Vs. Hangar 111
I was intrigued by Hangar 111’s claim “ we went back to the drawing board to re-invent the sports exhaust”.
I’ve been designing and building “Sports Exhausts” for over 30 years and decided to compare my 2ZR system with the Hangar 111 exhaust supplied to a 2ZR owner.
Check out the results below!
Compared to the 2bular design, the exit pipework from the Hangar 111 silencer has an awkward mismatch in the bend radius. Their pipe is only 60mm diameter – 2bular 63.5mm.
The oval tip is very small and doesn’t fill the diffuser exit. It’s the only part of the exhaust you can actually see – so they might have made the effort!:
You need the larger bore on a supercharged install.
An e-mail from the disgruntled 2ZR owner told me this Hangar 111 exhaust was “unbearable” – LOUD and dronnnnnney. It is a 7”dia silencer. The minimum silencer diameter I use on these cars is 8” – that 2ZR motor with its long stroke is VERY vocal.
Some aftermarket companies look to cover most of the Lotus exhaust world with ONE exhaust design. Only 2bular design and build an exhaust for EACH Toyota motor. Dronnnnnne is a common fault reported to me by customers of other aftermarket exhaust suppliers. It is NEVER a case of TADTS (They All Do That Sir). If you try and fit the same design to the Elise 1ZR AND the Elise 2ZR – you will have problems – LOUD and dronnnnnning problems.
Now, a “Sports Exhaust” should at least improve performance by providing an easier path for the gas-flow. That means a “straight-thru” exhaust design. You can see the factory design is a “Z-Flow” layout (or 3-way) with the gas-flow interrupted and reversed twice to allow the sound to be controlled better – restrictive and not great for performance. Standard fare for a factory system though.
Hangar 111’s “re-invention” of the sports exhaust is even more restrictive, almost labyrinthine in its layout as you can see below. From the simple 3-way factory system:
After the entry pipe, the gas-flow is split in two – this may be where the dronnnnnne issue is caused.
The final section is problematical. The divided gas-flow is reversed through the restrictive perforated baffles, then finally out through the swaged section with its holed circumference. This section is where I think control of the sound is lost - hence the LOUD issue.
Hangar 111 claim construction is 304 Stainless Steel (non-magnetic) but I found mild-steel parts internally – not great for longevity.
So, “re-inventing the sports exhaust” according to Hangar 111 apparently means producing a LOUD, droning exhaust which will rust internally.
IMPORTANT: I advised the 2ZR owner to claim a full refund from Hangar 111 but he was told as the system had been “used” that was not possible. Mr Greg Lock – Managing Director of Hangar 111 – told him he would “ask around the race teams if they would take it off his hands”. 2ZR owner is still waiting.
When you buy an aftermarket product you MUST ask the right questions and get the answers in writing. If the 2ZR owner had asked if the Hangar 111 dronnnned at all and had a negative reply he would have had a very strong case for a full refund. Under the Consumer Rights Act 2015, all products must be fit for purpose and as described. The fact that the exhaust has been “used” doesn’t matter! How else do you find out if it’s as described?! Your local Trading Standards Office will be delighted to help you, especially if you have written claims of quality and fitness for purpose.
Lotus Stage2 Exhaust:
When I first heard this system, I thought it sounded fantastic. Although I wasn’t that keen on the tailpipes jusssssst poking through the diffuser and the owner advised me he had to trim the diffuser panel for clearance on those 89mm diameter tips.
Once I had a drive in a 111R with it fitted, I soon changed my mind. The dronnnnnne was horrendous.
We got the car up and checked the layout. The silencer was 5”diameter(!) – pretty damned small for a 170bhp motor.
The big tips certainly contributed to the dronnnnnnne and cutting open the silencer showed a very small bore perforated tube with poor quality packing materials.
Standing back I could see this was designed by a firm experienced in mild-steel exhausts but the 300series stainless used in modern aftermarket exhaust systems has a co-efficient of expansion 1.5 x that of mild-steel. It MOVES - a LOT - when it’s hot AND it shrinks a LOT when it cools. If you don’t take account of those properties – in other words, allow the construction to expand and contract and don’t try and tie it down, you’ll be fine.
However, inexperience can lead to stuff like this –
And this –
You see those mild-steel hanger rods? Always a bad idea to mix mild and stainless. A pet hate of mine – along with the horrible stretched pipe used as a 1-into-2 collector for the tailpipes. Just pull the two pipes together, use the squirt gun (MIG-welder) to fill in the gaps and slide the stretched pipe over them both. Weld what you can, then bash the middle down till it meets your fill-in weld. Seal it up – lovely! Urrrgh.
I recall Lotus dealers fitting this exhaust to the supercharged cars until they were advised in no uncertain terms NOT to do this. The bore is barely advisable on an N/A motor, never mind a supercharged beast.
However, I bet there’s some supercharged car owners out there still with this exhaust fitted to their pride and joy!