Exhaust/muffler clamp -- Lotus TSB

[Jack]

Just a heads-up, Lotus recommends that the exhaust/muffler clamp never be re-used in the event the exhaust is ever re-fitted.... Here's the TSB

SERVICE BULLETIN...Model:Elise/Exige/Europa/2-Eleven...Date: 25.02.08

TITLE: Precautions when re-fitting exhaust muffler on any Europa or Toyota powertrain Elise/Exige/2-Eleven.

REASON: To ensure adequate sealing and security.

The slip joint between the catalytic converter outlet 'U' bend and the exhaust muffler is secured by a strap clamp and pinch bolt. This clamp is designed to apply the correct clamping force to the pipe when the pinch bolt is tightened to the specified torque of 54 Nm.

In order to guarantee this result, the clamp is for one use only, as some stretching and settling of components will occur in service. Be aware that the security of this joint is essential to ensure the integrity of the exhaust system, in respect of emissions, noise, heat release and safety. Extreme temperature gradients and powertrain shunt (especially with track use), will subject the joint to additional stress, and for cars used on closed circuits or in similar conditions, the Pre-Track Use Check List, LSL520 should be followed, which includes an operation to check the exhaust system for sealing and security.

ACTION: If an exhaust muffler is at any time removed or replaced, the following points should be observed:

1. Ensure that the clamp (A120S6000S or B116S6001H) is renewed, if necessary cutting the tack weld (used only to assist factory build) with a precision rotary tool to remove an old clamp from a muffler which is to be re-fitted.

2. Position the new clamp to be flush with the end of the muffler pipe, and orientated with the clamp split equidistant from the two patented joggled seal slots in the pipe. Tack welding the new clamp is not necessary.
Note that all new standard fitment mufflers, and Lotus accessory sports mufflers LOTAC05334, LOTAC05335 and LOTAC05450, are supplied with new clamps tack welded in position. Elise S sports exhaust LOTAC05391 will require a new clamp, A120S6000S, to be ordered separately.

3. Dependent on model, be aware that the optimum position of the muffler may not be determinable without trial fitment of the diffuser in order to centralise the tailpipe(s) in the diffuser aperture (note: access to the clamp is not available with the diffuser fitted). In this situation, the clamp bolt should be only nipped up for the position assessment, prior to torque tightening on final assembly. Achieve the maximum possible engagement of the 'U' bend pipe into the muffler inlet, consistent with acceptable tailpipe position. Assemble the joint dry.

4. Finally, torque tighten the clamp bolt to 54 Nm. From this point onwards, the clamp should be discarded if the clamp bolt is slackened.

5. Manually attempt to slide or rotate the joint. No movement should be possible.

[waydui]

Jack,
Good reminder.

When I replaced my stock exhaust with a Stage II, I replaced the old clamp with a new one.

The original clamp was actually too big for the Stage II pipe, so I really had no choice.

Pics of OEM clamp and replacement one.

Regards,
Wayne

[OTB]

Yeah, I have stage 2 and my exhaust clamp won't stay tight even with red loctite on the threads.

Would you have a part# or something for the clamp you used?

thanks

[waydui]

Originally Posted by OTB

Yeah, I have stage 2 and my exhaust clamp won't stay tight even with red loctite on the threads.

Would you have a part# or something for the clamp you used?

thanks

Hi Eli,

I used a SuperTrapp Stainless Steel 2-1/2 inch "T"-clamp for the exhaust to cat fitting. It has a lock nut on it so it stays tight and doesn't back off. It's been on for over a year with no issues. Cost about $11.

Here is the link to the specific clamp I got: http://store.summitracing.com/partde...5&autoview=sku

Hope this helps.

Regards,
Wayne

[OTB]

I'll get one of those.

[lapthis]

No wonder mine kept popping off.....

[waydui]

FWIW, here is a link to my install thread for the Stage II exhaust:

STAGE 2 Install How-To w/pics

It explains each of the steps with pictures.

May help others with exhaust install issues or problems.

Regards,
Wayne

[charliex]

i'd do the same with the clamps on the intercooler on the S too, they wear out fast, i replaced my drivers side one recently as it popped off during driving, and i just noticed my passenger side one is leaking. i take my driver side one off a lot though.

[codymac]

Turbo guys figured out a long time ago that you can usually pick up decent T-bolt clamps at NAPA.


Got whatever came with an old Yoshimura on mine.

[CosmosMpower]

Originally Posted by codymac

Turbo guys figured out a long time ago that you can usually pick up decent T-bolt clamps at NAPA.


Got whatever came with an old Yoshimura on mine.

I went to napa and asked for a 2.5" T bolt clamp, they said those are mainly for silicone hoses not exhaust pipes. Your thoughts?

[Needspeed]

My stage 2 came with a new clamp… what gives??? Why didn’t everyone else get one with the stage 2 exhaust?

[codymac]

Originally Posted by CosmosMpower

I went to napa and asked for a 2.5" T bolt clamp, they said those are mainly for silicone hoses not exhaust pipes. Your thoughts?

I'd have to see it to say - I only use ABA clamps on silicone.
Can always mail order from Summit.

[CosmosMpower]

Originally Posted by codymac

I'd have to see it to say.
Can always mail order from Summit.

Ended up just getting a standard U joint exhaust clamp seems to work fine except it basically crushes one pipe onto another and it makes it a real PITA to get the exhaust off the cat next time.

[codymac]

Originally Posted by CosmosMpower

Ended up just getting a standard U joint exhaust clamp seems to work fine except it basically crushes one pipe onto another and it makes it a real PITA to get the exhaust off the cat next time.

Sounds.... ghetto.


These things are slip fit, a lot more like a motorcycle exhaust than a car exhaust - at leasst, to me.

[Faze]

Originally Posted by CosmosMpower

I went to napa and asked for a 2.5" T bolt clamp, they said those are mainly for silicone hoses not exhaust pipes. Your thoughts?

Yeah, I would have to agree - and for coolant lines. Note that the lock nut will be rendered ineffective the first time you heat the exhaust up and the nylon melts.

With that said, I have one of the t-bolt clamps on my Larini exhaust and it has held up well.

[CosmosMpower]

Originally Posted by Faze

Yeah, I would have to agree - and for coolant lines. Note that the lock nut will be rendered ineffective the first time you heat the exhaust up and the nylon melts.

With that said, I have one of the t-bolt clamps on my Larini exhaust and it has held up well.

Link to said T-bolt clamp?

[Faze]

Originally Posted by CosmosMpower

Link to said T-bolt clamp?

Summit P/N SUP-094-2500

SuperTrapp 094-2500 - SuperTrapp T-Bolt Exhaust Clamps - summitracing.com

[def]

Ok what was the verdict on this clamp?

My exhaust fell off yesterday while autocrossing. Need a new t-clamp... advice is appreciated
Will also be getting the engine mount inserts to assist with the problem

Edit: Well just ordered the above one... I'll give it a shot

[waydui]

Originally Posted by def

Ok what was the verdict on this clamp?

I've had my SuperTrapp T-clamp on for 1 1/2 years with no issues.

I removed the clamp once to put the Arqray decat pipe in and re-used it. Nylon lock-nut was still intact, no melting.

Regards,
Wayne

[Bane]

You get a free new fancy clamp with every purchase of a PPE header