EXHAUST MANIFOLD IRON VS STEEL ?

[giorgio67]

HI guys,

last part missing on my finished chassis is the Ex. manifold.

The SS Sj version was on my plane but I've found locally a brand new cast iron original Lotus type.

Now I'm thinking about, the pros & cons of the two type?

The original type don't need the cross brace to be modify (it's stainless steel and expensive) so I'd like to know your thoughts about that, also price for the cast iron type is ridicolous.

 

Giorgio

[GavinT]

I have been told that the original stock manifold was very good, in terms of exhaust gas flow. If you didnt install the intermediate silencer and just went with a single free flowing performance silencer you would get a descent bump in power. I think Jeff at JAE said they were getting 190 bhp with the stock manifold back when he would do engine work on the 907.

Have you seen RD's manifold? it's pretty cheap compared to the others and looks like a good alternative to the stock one.

[giorgio67]

HI Gavin,

yes I know about the RD manifold but the original one I've found will cost me about 180 Euro so very cheap and I think the differences to the SJ is not worth the money, I think to buy it.

Also I can have it ceramic or coated or something similar.

 

G.

 

PS:

does anyone knows about the differences between the S1 and S2 manifold?

Different parts number reported on the Lotus Bible

[vintaylor]

Hi Giorgio,

 

Can you send more details about the RD manifold ?  I am also looking into getting an exhaust done sometime soon.. Was thinking of having the full system done in s/s in Malta

[giorgio67]

Hi Vin,

I've no more details about it, you can see it on the RD site and Bibs got one long time ago....

G.

[GavinT]

I too was going to get the SJ one but when I found out that it didn't fit without modification I lost interest. For the price it would cost to get it to me here in the US I would expect it to be a straight forward bolt on. I know Renn had issues with his. Things not fitting or lining up very well.

[vintaylor]

Do you have a link to the website .. can't seem to find anything on google :/

[GavinT]

http://www.rdent.com

Click on the Esprit Elite Éclat menu, then click on 3rd gen parts. Scroll down, it's listed almost at the bottom of the page.

Edited May 30, 2014 by GavinT

[Paul Coleman]

I too was going to get the SJ one but when I found out that it didn't fit without modification I lost interest. For the price it would cost to get it to me here in the US I would expect it to be a straight forward bolt on. I know Renn had issues with his. Things not fitting or lining up very well.

I double checked this with Steve before I bought mine (I have the whole s/s system including manifold) and he told me that it would fit my car as it's an early S1. I think it has to be modified for the later cars, so it all depends upon how early the car is.

 

Paul.

[deecee]

Lotus chose a cast iron manifold for noise reduction.

 

The problem with the S3 manifold(other than cracking due to the weight of the manifold) was a hot spot that would blow a hole in the recess between the rear and second from rear cylinders.

 

The intermediate manifold, between the main manifold and turbo, was also prone to heat erosion on the divider between the 2 ports.

 

Some people replaced the intermediate manifold with a make shift intermediate manifold...I believe it was from a Cessna Airplane.

 

The newer cast iron manifold design on the Stevens Esprit, (without the integrated wastegate) solved both problems, and would be my choice.

 

To control the boost, you could used the wastegate integrated turbo, a god Tial Blow Off Valve, or both.

 

I would also recommend a Remote Wastegate Control so you can dial in the amount of boost that you want.

 

In closing...some Esprit required several new manifolds due to heat and/or strength related problems, whereas others still have their original manifold and have never had a problem.

[Bazza 907]

Buddsy

Unfortunately the original cast iron manifolds go just as easily and as quickly on N/A cars as they do on the Turbo cars.

 

It' may not be the sole cause but manifolds often seem to go when the rear wheel throws up water on to a red hot manifold so avoid floods !

[OwenGT3]

Since fitting my new manifold about a year ago, which was an original Lotus cast iron item, plus I use my car in the winter so plenty of rainy days, I've added an extra alloy shield to help protect the manifold from wheel spray. It was easy to make as it's flat and it's jut held on with four jubilee clips around the chassis tubing. Maybe this can be done on the earlier cars?

 

Edited June 5, 2014 by OwenGT3

[peteyg]

I'm happy with the SS manifold from SJ. It weights a lots less than the cast iron manifold and sounds a lot better. Easier to remove in situ as well if you need to.

 

The modification needed on the S2 is with the bolt on chassis brace. It needs to be moved outwards by about an inch where it's bolted at the front. It's not a difficult mod, just needs a small bit of welding. I don't have a picture to hand but I welded a piece of steel tube identical to the exiting one where the botle slots through onto the right hand side of the existing one.

 

I'll pull out a pic later.

 

Pete

[GavinT]

I think the early S1s didn't have that brace. My S1 does.

[giorgio67]

The previous owner fit a full SS exhaust system, so I have the parts and the SS silencer.I

 think to fit original cast iron manifold and the full SS section to silencer but without the intermediate silencer so I would buy the intermediate link from SS.

The cost is very very low and I can save money for my leather interior.

Giorgio

[gvy]

Giorgio,

 

Why should you leave out the intermediate silencer.?

My S2.2 has it and I see no reason of removing it or do I miss something?

 

Greets

 

Geert

[giorgio67]

Hi Geert,

no you are missing nothing...but lot of people here said that the noise is much better.....

 

Ciao

Giorgio

[peteyg]

It is!

[Freemason]

I'm happy with the SS manifold from SJ. It weights a lots less than the cast iron manifold and sounds a lot better. Easier to remove in situ as well if you need to.

 

The modification needed on the S2 is with the bolt on chassis brace. It needs to be moved outwards by about an inch where it's bolted at the front. It's not a difficult mod, just needs a small bit of welding. I don't have a picture to hand but I welded a piece of steel tube identical to the exiting one where the botle slots through onto the right hand side of the existing one.

 

I'll pull out a pic later.

 

Pete

 

I'm considering getting the complete SJ system. Steve informs me that when fitting the four into one manifold I'll need to "modify the diagonal brace on the left side". Does anyone have any pictures and tips on how to do this?

Edited September 25, 2014 by Freemason

[Simon350S]

If you are going the stainless steel tubular route I'd highly recommend speaking with Mike at LotusBits. It is leagues ahead of that other one you are talking about. It is more money, but from what I've heard its money very well spent.

LotusBits have put a lot of time and money over the years developing that exhaust system and I've never heard a bad thing said about it.

Edited September 25, 2014 by Simon350S

[mdw]

You could also try alunox.  Last year they made 2 n/a systems for stevens models.  I have no idea if that was it due to small number of cars needing it compared to turbo manifolds however it might be worth contacting them.   The Lotus bits system Simon has suggested would almost certainly be available quicker.   The main reason I didn't go Lotusbits was they hadn't fitted one to a Stevens n/a and I would have to take my car up there and leave it for a week for final manutacture.  The price was a little cheaper from Alunox for their system then  add in 400 miles of fuel 2 days and 2 one way rail tickets for the Lotusbits system and it was going to cost me a fortune where as the Alunox turned up in a box the next day and I fitted it in 2-3 hours ( old manifold already off). 

[skiing]

I have the lotusbits one - it does, I think, sound fantastic - so much better than standard. I have an HC engine in mine with 48 carbs (re-jetted) and lotusbits exhaust and the car goes like a rocket... The only thing I would change is that it has a single tail pipe and I prefer the look of the twin pipe. It is also a close fit around the chassis so I have heat shielded the chassis near the exhaust. 

[Freemason]

I'd definitely be interested in the Lotusbits complete exhaust if it is the best out there. Looking at their website though it seems to actually be cheaper?

[Simon350S]

Do it

You'll not regret it at all I'm sure. Mikes spent a lot of time developing the esprit engine to run in his rally cars so I'd happily trust his knowledge and experience.

[Freemason]

Ah, I found the £1200 S2 exhaust system in the 'upgrades' section of the Lotusbits site. Cheap it ain't but have heard good things about it.