Alunox Turbo manifold

[MarkKassim 79]

Hi Guys,
             I’ve noticed your thread and read about your problems with the cast manifold and external waste gate on the Giugiaro Esprit’s. I’ve contacted Alunox and explained the problem. Alunox supply the 321 Stainless Steel tubular manifold for the Stevens Esprit , which has been very successful and has become a recognised replacement, giving the Steven’s owners an upgrade in both performance and reliability.
Alunox are interested in providing a new tubular stainless steel manifold for the Giugiaro Esprit as a direct replacement for the original. It will use a motorsport grade external wastegate mounted on v bands.

The new manifold will be constructed of 321 stainless steel and will have a similar construction to the existing Steven’s manifold as shown above. The wastegate and return pipe to the turbo will be included in the final product.

Alunox need to finalise the design and need a car at the workshop in order to do this. Alunox are based in Wrexham about 10 miles from Chester. Would anyone be willing to take their car to the workshop so final measurements can be taken.

Once this is done I can put up photos of the finished product along with prices. This could be in production in days.

I have already asked Leon at Alunox about a Group Buy on this manifold to get the price down. This has been approved and also he will allow us to combine the Group buy with the Steven’s manifold to greater numbers and so a better price.

Let me know if you would be interested.

Mark

[jcslocum 97]

Mark, Count me in for 1 piece!!!

 

 

[stephenwhyte 2,006]

Sounds interesting - will this option be strong enough to support the turbo......and would it be designed to attach to the standard turbo or instead for a modern equivelant? Finally do you have any idea how much in terms of cost would we be looking at for one manifold set Mark?

I personally would like to keep my car as original as possible but won't dismiss any solution and would be interested to learn more about this option.

[hopo 154]

This sounds pretty interesting - what is a ballpark figure for costs?

[MarkKassim 79]

Hi, I’ve been In touch with Alunox, the design isn’t final yet, the full manifold replacement will include wastegate adaptor integral to the design, the wastegate return pipe to the turbo and the wastegate itself.

Yes the system can support the wait of the turbo and the design will probably include a brace for shock loading proven in the Stevens design. The turbo flange will be for the existing turbo, but Alunox change to suit on request for a small fee.

These are the estimated prices

One off around £1400

Group Buy of 10 - £1200

If we can get a group buy nearer 30 then we can get this price down further. One of the reasons being for a bigger production run it becomes more cost effective to produce using a CNC made collector piece with built in wastegate flange as below.

We can combine the next group buy with the Stevens Esprit as well as they share common components.

The Stevens manifold has been dyno tested on a high powered Esprit resulting in a performance increase in both torque and power and also lag reduction. The figures for this car were 424BHP and 409lb-ft torque. The manifold was the only component changed for this run which resulted in 64lb-ft torque over the previous performance manifold @ 4500 rpm. The result was filmed as below

 

Alunox are still looking for someone to bring a car to the workshop so final measurements can be taken, is there anyone close to Wrexham in North Wales.

Mark

 

[PhilW 403]

This is great news generally. i currently have my name down for 2 cast ones with Bibs if Lotus will do a new run.  To be honest I would prefere this for originality sake especially for the dry sump.  I think this is what I will stick with at the moment although if that run comes to nothing then I will go down this route.  

[MarkKassim 79]

Hi Guys ,

             Just an update this is the collector as seen earlier in the CAD drawing , the other flanges will follow soon. Once a full manifold has been produced I will post. 

These are CNC machined from a solid block of stainless steel.

Flange CAD drawings

The waste gate return pipe will be mounted on V bands . 

Mark

 

[jcslocum 97]

That looks wonderful. Machine work porn for me. If you had a video of the CNC working, I would watch it!

[Neverweaken 13]

Hi Mark,

i am interested in an alunox manifold.

keep us posted.

[greentengu 14]

Hi Mark:

I'm with Neverweaken in that I am absolutely, positively interested in joining a Group Buy of the Alunox manifold. Note that I was informed of this thread via a link given by Travis, a.k.a. "Vulcan Grey", who responded to one of my posts on Lotustalk.com. 

Do you think, perhaps, this entire section could be broken off and re-started as a new Topic? As I was not interested in having an OEM manifold purchased (mine's fine, if extremely...heavy...for now), I would not have thought to look at this Topic for information on the Alunox manifold and all the other pieces they are so beautifully crafting for the G-Esprits, and would have passed right over it!

Regards,

Scott Landis

Quakertown, PA

USA

[MarkKassim 79]

Hi Guys,

              Alunox are getting a car in the workshop next week , so I will be able to get some shots of the new manifold when it is complete. They are also going to develop the rest of the system while they have the car.

Scott , yes I will start a new thread here and another under the main sponsorship area when I have the photos and if you can post anywhere else I can mail them to you. Just to give you some idea  the type cars Alunox supply full systems for

Lotus - think type 29

  

Jag E- type

GT40 - Races at Goodwood and Le Mans - worth over 2 million 

 

Mark

[Geeman 18]

For those of us with US spec Esprits will the manifold have to be tapped for the emission equipment?  Any US owners got a good photo or details they can provide?  Some US states still require emissions equipment, some do not (Heck, my state, SC doesn't have an MoT or equivalent?).  I think the manifold on my Esprit is OK, but I might be tempted to spring for a spare.  I wonder if there would be shipping cost advantage for a bulk shipment to someone in the US then use US internal shipping to distribute?  How many G Turbo Esprit US owners on even on here?  Would Alunox be able to cheaply tool/machine for US spec mods?

I am just thinking out loud a bit here, because this looks like some nice work and us US owners might want a piece of the action :-)

 

[greentengu 14]

Hi Mark:

Thank you for the update. 

As Gordon points out, USA-spec G-Esprits must often maintain Catalytic Converters. I'm one of those with a US-spec model. Here in Pennsylvania, we have both a "Sniffer" (tailpipe) test and a visual test for cars (even those with OBD-II systems). 

I'm sure I (and other members, of course!" of Lotus Talk can maintain and keep a thread on this exhaust manifold in (USA's) current. Keeping a thread current on that forum requires quite a bit of effort as, unfortunately, the website doesn't break down its Major Heading threads by Subheadings [e.g. there is no separate Engine, or Transmission, or Exhaust sections for the G-Esprits, just a stream-of-consciousness hodgepodge of threads on G-Esprits covering every possible topic).

That is, I'm sure there are others who would be more than willing to help keep a thread on the Alunox manifold updated and current ("To the Top") on the LotusTalk website.

I'm an extremely infrequent visitor to the turboesprit Yahoo! forum, but I imagine I could post there, and see what I can post as a member of the Philadelphia Area Lotus Society--the caveat being I am far from a well-known member of both groups, but can at least point members in the right direction.

There are far more other groups that could be contacted online, such as the Golden Gate Lotus Club (in California), Lotus Owners of the North, or LOON, in Minnesota (USA), etc.

Not sure, however, how to query them about joining a Group Buy (or individual purchase...although I'm not naive enough to believe some of their members are not already perusing this forum and reading these posts right now--so one would imagine they know of the possibility of a G-Esprit manifold).

Cheers,

Scott

[MarkKassim 79]

Hi ,

       Just an update , Alunox now have a car in the shop and work has begun on the new system, all the flanges are in 

and 321 tube to start bending for the new design.

I will get another update this week .

Mark

[rocket63 137]

That looks very nice Mark.

[Andyww 1,302]

Does going from cast iron to this type of manifold increase the exhaust noise? I am not a big fan of noisy exhausts from the point of view of drone in the cabin on long drives. Other than that concern this solution makes the original cast iron look prehistoric and I dont really see why anyone would favour the original over this.

[stephenwhyte 2,006]

18 minutes ago, Andyww said:

Does going from cast iron to this type of manifold increase the exhaust noise? I am not a big fan of noisy exhausts from the point of view of drone in the cabin on long drives. Other than that concern this solution makes the original cast iron look prehistoric and I dont really see why anyone would favour the original over this.

For exactly that Andy - to be inkeeping with the original Lotus concept & design. If my Turbo Esprit wasn't so original with low miles I'd probably think similarly to you.

[Andyww 1,302]

The question is, why did they go with cast iron originally? I would suspect the reason was simply cost.

The cast parts were probably cheaper to produce in those days but now the balance has tipped in favour of fabricated, with advances in CNC techniques and materials. Also being one of the first turbo engines there was a limited choice of wastegates whereas nowadays they are run of the mill items. 

The reasoning is the same for replacing the cast early pistons with forged or cast iron calipers with Wilwood machined alloy and vented discs. I dont have any emotional attachment to the cast parts in the context of concept or design. They are functional rather than aesthetic items. Anything visible I like to keep original but the manifold and wastegate are largely hidden. This update replaces three parts which are known to be problematic.

On the other hand, pictures of race cars with similar manifolds do nothing to attract me to the idea, as the requirements of a race car exhaust are totally different to a road car, hence the noise concerns.

[stephenwhyte 2,006]

I hear you Andy and totally understand and agree with your views but for me personally if I can get an original cast iron one back on I'll feel better with one of those for this car anyway. As far as price goes this will also be a damn site cheaper than either the Alunox or any other alternative solution.......this decision won't be driven by price but the saving will be gratefully appreciated and no doubt I'll spend the difference on some other area of the car as I'm pretty sure it has some other secrets it's hanging on to......

[Bloodnok 1]

I'm also very interested! As far as originality goes for me, it's easy enough to hang onto the old manifold if required in the future. It would make a heck of a paperweight!

[andmac 14]

I am also interested in this, the cast iron manifold that I took off had six large cracks in it so a stainless upgrade with modern wastegate sound great to me.

[MarkKassim 79]

Hi Guys,

               Just an update, the design is well on the way for both the manifold and rest of the system .Just to clarify, the manifold won't increase the noise levels that is really governed by your rear silencer system. The manifold will fit with the existing silencer system and also with the new system Alunox will be offering. This system will provide better flow while keeping noise levels down. 

Now due to the V band clamp setup on my SE which has the full Alunox set up, it is possible to interchange an extra silencer, and to give you some idea it runs at 96 dB (@ 4500 rpm 1m away) without the extra silencer and factory noise levels with it. It can be interchanged using a 13mm spanner in about 10 minutes.  It has been tested both at castle combe and the workshop. 

looking at the size of the new silencer for the G car I think it will be the same as the factory noise levels. If anyone will be interested in the rear system as well maybe I can get Alunox to spec it with an interchangeable silencer option to accommodate everyone’s needs.

Hi Scott, again using the V Band technology a high flow CAT option has already been incorporated into the design, I fed back your comments back to open this up to the US market.

Going back to price, the Alunox solution replaces both sections of the original cast manifold which I believe are about £580 each putting it at £1160 plus a new waste gate unit. I will hopefully have some pictures and final pricing next week.

I think a couple of options may come out of the rear system , for the CAT . I will confirm soon

Mark

[MarkKassim 79]

Hi Guys,

              I've got some shots of the new system for the G car which is now available from Alunox. This is the full system including manifold, external wastegate and rear silencer. The manifold will be available on its own with a different wastegate connector pipe. The entire system is made of stainless steel the manifold of grade 321 to withstand the high temperatures. 

In order to fit in the space available and maintain equal lengths on the down pipes there has been more bends and sections than first thought.

All sections are detachable on V - band clamps.

The rear system contains a new mounting bracket for the gear box, all in stainless steel.

Shown here with the CAT for the American market again mounted on V Bands. 

After finalizing the design the price may be a bit higher than the original ball park figure I posted earlier. I will pitch soon with the final prices and full details in the 'Site Sponsors and FFM' section of the forum

Mark

 

 

[jcslocum 97]

Exhaust porn right there. I'm very interested in this. Once you get pricing figured out, Can you also look to the cost of shipping to the USA?

 

 

[greentengu 14]

Amazing work! The V-bands are an excellent idea.

Heading over to Site Sponsors section to see how this is going.

Cheers,

Scott