Alunox 321 SS Manifold for Esprit Turbo Group Buy

[mr.oogieboogie]

Hello derek did you get yours sorted

[sailorbob]

Yep, the number 2 cylinder runner which caught the chassis gusseting has been tweaked. The latest group buy manifolds are being similarly made to improve the clearance.

[mr.oogieboogie]

Cool look forward to seeing it

[rotaryspeed]

How do you install that thing anyway ? Anything special to look out for ? Besides not loosing any nuts

[Dave Freeman]

I put a thread on here some time back with the details. Should not be difficult to find.

[MarkKassim]

OK I have a brace update. The new brace will be issued Free of charge to all customers who have bought a manifold. The final design as shown below, on mock up brackets the actual ones are due the end of the week.

This will be more than adequate for the standard Turbo weighting.

However Alunox are offering a further design for those who have fitted bigger turbos, its a dual rod design giving greater shock loading protection.

The dual rod design is available at £80 for those who are interested.

Contact Alunox if you require this.

I will update you with any further developments.

Mark K

[Simon350S]

Nice one Mark!

That double one is looking much more like it, with what looks like a double mounting to the engine/gearbox as well, cracking

[MarkKassim]

Hi Simon, Yes it is a double mounting to the gearbox ,this might show it better

Mark

 

[Sparky]

Mark, gotta say what a joy that manifold is to fit. :-)

[Chillidoggy]

In that case, you can fit mine when it arrives.

Oh, did I mention the small point about taking the old old off? No, oh well, never mind.

[Vulcan Grey]

The best turbo support bracket I can recall seeing was the one where the bracket was a continuation of the manifold to head mounting flange.

Not sure how that one frared long term though.

 

This is the one you are thinking of.  The Al B. manifold.

 

http://www.thelotusforums.com/forums/topic/21635-custom-exhaust-manifold-for-esprit-se/?p=216490

 

 

Or this one from Dr Hess (early prototype I think)

http://www.thelotusforums.com/forums/topic/24385-stainless-steel-exhaust-maniflod/

[mr.oogieboogie]

Yes dr hess was very helpful to me when i got mine made with the specs etc. Good guy i abandoned the al manifold which i had a deposit on via germany as it was having issues.

realy pleased with mine took it off some months ago to inspect it and its still fine althought not shiney

[Simon350S]

Yup, that's the one Travis.

I wonder how well It fared in daily use?

[Simon350S]

Hi Simon, Yes it is a double mounting to the gearbox ,this might show it better

Mark

Hi Mark

I've had a bit of a thought about this, what would be the mileage in having those linkages mounted in a cross over fashion?

As they are, they still provide nothing in the way of lateral support only static weight and direct vertical shock loading support

If they were mounted bottom left - top right on one side of the bracket, then the other bottom right -top left on the other side of the bracket then this would combine direct support and shock loading in the vertical axes and also provide ridged support against any lateral forces/shock loads during use. It's all bases covered whilst still allowing fore and aft movement if required to satisfy any thermal expansion issues.

Either that or weld up a cross over joint with some threaded tube and the spherical rod ends as per your photo, that may well look a lot neater and function better but involve a little more work.

Edited September 9, 2014 by Simon350S

[Vulcan Grey]

I agree that the supports need more thought.

 

While 321 Stainless steel is better than some steel alloys, since it is "Titanium stabilized for service in 800 to 1600F range and to minimize carbide precipitation when welding for resistance to intergranular corrosion." from the MIL-HDBK-5J...  It still looses 40% of it's tensile strength at 1000F, and loses 60% of it's tensile strength at 1400F.  

 

Which is why the thin manifold tubes MUST not be used to hold up the turbo.  Hence the bracket support.  BTW, the cast iron alloy used in manifolds doesn't lose much strength at these high temperatures.  Cast iron is much better at damping vibration as well, another reason why it is used.

 

In the single brace version, the brackets shown above are bolted to the hottest part of the turbo, the bottom flange before the turbine.  They are made using bent "thin" sheet metal, with fairly sharp bends, that I'm fairly certain will crack, due to fatigue, and fail.  Also the double pinned joints with spherical ball joints, as seen on the single support bracket, cannot support anything except a load in tension.  Any sideways load, moment, or compressive load will not be supported and the manifold will be seeing the weight of the turbo (at least at an angle rather than straight downward).  Also the thin tab that bolts the single brace to the transmission is not optimized for the loads.  it will twist and bend.

 

The dual brace system is also has problems IMO.  The links being parallel and with the same dual pinned + spherical ball joints, cannot support a sideways load or moment.  It would be better, if they were angled into a triangle to resists lateral movements.  The tabs that bolt the links to the hot side of the turbo will still fatigue and fail, especially at the expected temperatures...  And the brackets to the transmission look a little too cantilevered to support the weight.

[Vulcan Grey]

Yup, that's the one Travis.

I wonder how well It fared in daily use?

 

Simon,

 

I think Al B. had 30 made.  I haven't heard/read of problems as far as I know.  I think Dr. Hess only made one or so, his car burned much later and he bought an Elise, and then wrecked that a few days ago...

[MarkKassim]

Hi guys I can see your way of thinking, making a more rigid structure to reduce the lateral movement. The only thing is this is only for the protection of shock loading in the vertical plane and must also allow for the expansion of the manifold which may move in all planes. I think we're probably splitting hairs here and this has already been discussed at length in the other thread.

 

Sparky I’m glad you enjoyed fitting that, what’s your thoughts on the performance increases.

 

Just one thing, those of you who have had brace breakages can you e-mail Leon directly with some photos if possible.

 

Thanks for your input.

Mark

[Sparky]

Mark, I hope to have the car running at the weekend, so will feed back then...

[MarkKassim]

Hi Guys just an update on the brace, Alunox had the brackets for the brace made but the quality was not upto scratch ,so they are being remade. Here are the cad drawings if anybody is interested.

This has delayed things by a week , I will update you when I know more.

Mark

[rotaryspeed]

Awesome !

[rotaryspeed]

I just received my manifold and its looking awesome Now I just need to install it.

[dodge1979]

Cammy, how has your manifold turned out..

[cammmy]

It's good. Not as advanced as the Alunox unit but definitely spools a good bit earlier and pulls harder. Most noticeable is on up shifts. This one starts boosting again much quicker whereas the standard part left you waiting for 1-2 seconds before suddenly hitting you. I'll start a thread for it after putting a fee more miles through it, rather than hijacking this one

[MarkKassim]

The new brace is being sent out this week if you haven't already received it the fitting instructions are as follows:

 

The new brace kit comes with new brackets top and bottom and a turnbuckle. The turnbuckle allows for better adjustment of the brace length due to its left and right hand threaded rod end bearings.

1. Remove the M8 Stud from the existing top bracket on the turbo flange using a hacksaw. This will make room for the new bracket.
2. Remove right hand turbo bolt and refit with new top bracket as shown. Tighten turbo flange bolt to Lotus specified torque setting.
3. Remove bolt from the gearbox and fit new lower bottom bracket. Tighten to gearbox ensuring it is straight in the horizontal plane as shown.
4. Place washer over the stud of the top bracket then attach turnbuckle followed by nut and tighten.
5. Slacken lock nuts either side of turnbuckle. 
6. Adjust length of the support by rotating the turnbuckle allowing the lower bolt to align with the hole in the lower bracket.
7. Push bolt through and tighten
8. Adjust turnbuckle to extend the brace length, to the point where the slack in the rods end bearings is removed.
9. Tighten lock nuts on turnbuckle.

 

The condition of the rear silencer mounts should be checked. As any excess movement could damage the manifold system.

 

Mark K

[sailorbob]

Having left and right hand threaded rod end bearings on the turnbuckle is a good improvement. I was surprised to find the original wasn't like this.