Manifold cracked

[mercman]

Hi guys,

My exhaust manifold was blowing last week and on checking it I found a large crack between cyls 3 and 4, I phoned around and can't get one, apparently they are now obsolete and not made anymore .

Anybody know where I can get one.

Anybody bought one of the SJ conversion kits ( any reports / photos of the kits ).

Les

[Tentenths]

SWLC iron manifolds (scroll to foot of page)

[mercman]

SWLC iron manifolds (scroll to foot of page)

tried them first, they don't do the S3 turbo manifold only the wastegate manifold.

Les

[bigsi]

they had one sat on the table at donny which they took back with them , and the wastegate adaptor section. as i was joking with james about wastegate section how i dropped it the year before when i realised how much it was. ring back and get them to check again. the main reason there isnt a stainless system coming from the engine is the fact it has to support the weight of the turbo, now you could get a stainless one made and have that go upto one of the later turbo units which would need some water cooling plumbed in, however you would then need to support the turbo in position which would require some fabrication.

give troy halliday a call and see if he has a spare turbo manifold there at his workshops, if i remember rightly he may have one spare, do a search for him here and his new mobile number.

also try mike taylor at lotus bits and paul mattys

after this there is one other option which will involve going to a foundry, you need to find a foundry that does iorn castings and sand pours, they will heat up the whole manifold to cherry red and then red weld it back up, its the olny way you can re-weld a cast part and they will do it properly, if you get no joy with the other options let me know and i will ask my old engineering boss who he can reccomend for the job.

Edited August 14, 2008 by bigsi

[bigsi]

cherry red weld is the right way buddsy, i did double check it with my old boss who used to be able to get cast weld that way.

he said because of the thickness of the cast and the grade of metals it would need a cherry red weld for it to be done properly.

getting a new sandcast would be great however its a new cast everytime which would be a severe costing, unless a wax based premould was done then the sand around that so the wax makes the centre tunnels and chambers then heated up so the wax drains out and then pour the cast. i love watching the old casting processes, be good if its possible to get that done, and also see if there were enough people to justify the costings.

[mercman]

Thanks for the replies guys, Iv'e decided to go for ther SJ conversion, quite expensive but if it's this difficult to get a manifold now what like will it be in a couple of years down the line should it go again.

Les

Edited August 14, 2008 by mercman

[mercman]

What is the Sj conversion and how much does it cost?

Buddsy

The conversion allows you to fit an S4 exhaust manifold, turbo etc.

In the kit you get the following parts:-

S4 Manifold

S4 modified turbo

Coolant pipe conversion kit

Exhaust pipe from turbo to box

all nuts, bolts, gaskets and sundry parts to complete the conversion .

Sj have carried out the conversion on several cars and sold several kits.

The kit is

Edited August 14, 2008 by mercman

[eengel1]

what about this ?

http://www.muggyweld.com/ssclip4.html

would that work or are they just showing off ?

Cheers

Marc

[andydclements]

I doubt silver solder will have a high enough melting point to cope with the manifold temperature, since ours can glow quite hot - red but normally below cherry red.

So yes you could joint it, but it's not blending with the existing metal it's merely doing what any solder or braze does and sits on the surface, so I'd have thought a good run and it would have melted and run away.

Andy

[bigsi]

try these for repairs.

http://www.shiltoncastironandwelding.co.uk/

[dazmans3]

When I put my HC engine in, I had the choice of Staying with the orriginal external wastegate set up(as then I was keen to stay with the HC S3 turbo spec) or, as it came with the engine anyway, the later Turbo with integral wastegate. I decided on the later as I'd heard that getting parts for the old style wastegate was now near on impossible. However, only last year when I did all this, Exh manifolds for the S3 turbo were plentiful. Have you spoke direct to Lotus on this?

Unfortunately the Manifold that came with the engine had cracked(surprise surprise!) & because someone had tried to weld the manifold crack, bits from the welding job had been sucked into the turbine thus damaging the turbo exh turbine.

The conversion itself is fairly easy to do. I did get some of the bits from SJ, ie Turbo to Exh down pipe & blanking bit for S3 silencer, Alloy Header tank with extra in pipe for turbo water return. The only thing here you'll have to figure is were to take the water to turbo pipe from. With the HC engine, for the heater feed it's rubber pipe all the way from the head at the back of the engine to the chassis pipes. So is easiy to cut in a 'T' peace. where as the S3 turbo has metal pipes that wrap around the plenum chamber.

I used the S3 turbo Manifold, as I had a spare anyway & the exh blanking spacer(which replaced the external wastegate). But when this does go then I can use the later SE/S4 manifold.

Take a look at my HC conversion Thread, got loads of photos on there that might help.

S3 Turbo HC conversion

Also check out my Splash gaurd. one of my theorys to the Exh manifold cracking is the when it rains all that cold water spraying derectely onto the hot manifold.

Daz

Edited August 16, 2008 by dazmans3

[mercman]

It was Lotus that told me the manifolds are now obsolete, the guy I spoke to suggested that I phone around the dealers in case someone had one lying in stock as that was the only way I was going to get a new one. I tried that without success.

Thanks for the link, very interesting reading

[mercman]

When I was calling around looking for a manifold, the person I spoke to at SWLC said that it was going to cost

[dazmans3]

15g, That is a lot. Surley Lotus got them made somewhere. so that somewhere must still have the molds. or doesn't it work that way?

I kinda wish I'd got one as a spare last year, but all my funds then were going on the engine conversion. Still, I wonder were so many have disappeared to since. Either there have been quite a few esprits with new manifolds fitted or someone has bought them all up & is hording them.

[Guest Bosal]

I could organise the manufacturing of professional replacement manifold. Talking about a tubular full high grade stainless steel manifold.

Price is depending of the quantity wanted, the more we can put in an order, the lower the price. Ask around, inform your friends and collect your needs.

[bigsi]

you still have to support the wastegate and the turbo somehow, as the manifold takes the weight of all of this

[andydclements]

Thanks.

I think that's been discussed a few times and the concern is that the turbo being mounted as it is puts a lot of stress on the tubular maniold, and combining that with stainless (being more prone to stress cracks due to its nature) it seems quite likely that the tubular ones would also crack.

[USAndretti42]

I think the big problem is not the weight of the turbo but the heat cycling that the manifold goes through as you go on and off the throttle. At full chat the manifold can get cherry red while at idle the exhaust can be relatively cold. The manifold doesn't get heated evenly and different parts expand at different rates leading to stresses as parts are stretched and squashed by other parts. Making the manifold thicker and heavier slows down how quickly it heats up and cools down and thus reduces the number and size of heat cycles it goes through. A tubular manifold would suffer badly in this respect and would tend to crack around any welds. Some decent brackets could support the weight of the turbo so that should be solvable.

[Guest Bosal]

It is interesting to read all the concerns regarding the "manifold cracking". And indeed that are valid remarks.

I would suggest to make the tubular manifold out of feritic stainless steel, because that material has the lowest thermal extension coefficient and using the correct grade, it would be resistant against thermal oxidation.

We can offer our cable bracket as support for the "heavy" parts, such a support will not suffer from the thermal expansion of the manifold itself.

Some about a kind of splash shield to avoid water spraying on the hot manifold. Also a good idea, but take care the heat must be able to get away.

Anyhow, we're still interested to work on all these solutions provided that we can make a certain quantity.

[brado]

My manifold is OK but wastegate and adaptor pipe is knackered... How much you want for yours if you are selling?

Cheers

[mercman]

Sent you a PM

Les

[richardvg]

WHY DONT YOU GET SOMEONE TO MAKE UP A COMPLETELY NEW MANIFOLD-ONE OF THE ENGINEERS WHO WORK FOR THE MOTOR RACING FRAT WILL BE ABLE TO MAKE ONE-AS LONG AS THE BASE PRE THE EXHAUST REMAINS THE SAME.

[USAndretti42]

Richard, easy on the capitals, please, as it seems though YOU ARE SHOUTING WHEN YOU USE UPPER-CASE TOO MUCH.

Welcome to the forum, by the way. Don't have many members from South Africa. Last one moved to New Zealand.

[markt]

Yep - that would be me Trevor

Welcome to the forum as well Richard.

So whatcha got???

<<<< Not British racing Green is it?

[Guest Bosal]

WHY DONT YOU GET SOMEONE TO MAKE UP A COMPLETELY NEW MANIFOLD-ONE OF THE ENGINEERS WHO WORK FOR THE MOTOR RACING FRAT WILL BE ABLE TO MAKE ONE-AS LONG AS THE BASE PRE THE EXHAUST REMAINS THE SAME.

Well Richard,

We're in a good position to make a suitable manifold for your application.

We have experienced engineers and workers available and all material and equipment to bend, shape and weld the pipes. For just one piece it would be a lot of work, so it would be best to collect your needs, and let's start working on it.

Does someone have a useless broken part in the shop to start from? We would be happy to pick that up. Just contact me for more information. www.bosal.com