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Exhaust Header Removal and Cam Covers  Rating:  Rating
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 Posted: 09-09-2014 10:50 pm
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answerman
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Idle thought today.  This winter, when I won't be in any rush to get Ms. Jenavieve back together, I'm planning on ordering and installing the Delta 4 into 1 header (already installed the JHPS high performance exhaust last year).  I've read all the horror stories on how painful of a job the removal of the stock header is.

Also, I have been thinking of replacing the cam cover gaskets with the ones from the JHPS store, just because it seems like a good idea and also because one of the DPOs installed the upper cover upside down or backwards or whatever... (which actually makes it easier to add oil since the filler neck is at the front, but it just bothers me that it's upside down).

So, thinking through the process... what about coordinating the two jobs?

For those who have done the header removal, would you think there would be any benefit to removing the cam covers first?  Just to get a little more room to work in there?  It makes a bit of sense to me from just looking at it, but obviously I haven't actually tested this theory yet.


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 Posted: 09-10-2014 08:01 am
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gmgiltd
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Just spent the last few days doing a similar job. UK spec does not have the complication of the steering column and I was re-installing my Lotusbit's reconditioned cylinder head.
It's a lot easier with the cam housing removed so if you need to shim the valve clearances it makes sense to combine the work.

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 Posted: 09-10-2014 11:42 am
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jcdean
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If you are so inclined you may also with to consider having the header drop shipped to http://www.jet-hot.com/ (Jet Hot Ceramic Coatings, no financial interest in the company. I have just had good luck with them). Keeps some heat out of the footbox and makes them last a good long time. They will do the inside and outside on a unused new system.

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 Posted: 09-10-2014 11:50 am
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subwoofer
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answerman wrote:
For those who have done the header removal, would you think there would be any benefit to removing the cam covers first?

Cam towers? Yes. Cam covers? Nope. You don't gain any clearance worth speaking of, and you run the risk of debris finding its way into parts of the engine it shouldn't be in.

--
Joachim

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 Posted: 09-10-2014 04:26 pm
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answerman
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As always... lots of good feedback from you guys.  You have no idea how helpful this forum (and the people in it) have been to me... more responses below...

Last edited on 09-10-2014 04:30 pm by answerman

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 Posted: 09-10-2014 04:28 pm
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answerman
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jcdean wrote: If you are so inclined you may also with to consider having the header drop shipped to http://www.jet-hot.com/ (Jet Hot Ceramic Coatings, no financial interest in the company. I have just had good luck with them). Keeps some heat out of the footbox and makes them last a good long time. They will do the inside and outside on a unused new system.Excellent suggestion.  Like I said, this will be done over the winter when I'm in no hurry, so I will definitely look into having this done before installation.

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 Posted: 09-10-2014 04:29 pm
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answerman
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subwoofer wrote: answerman wrote:
For those who have done the header removal, would you think there would be any benefit to removing the cam covers first?

Cam towers? Yes. Cam covers? Nope. You don't gain any clearance worth speaking of, and you run the risk of debris finding its way into parts of the engine it shouldn't be in.

--
Joachim
Thanks Joachim.... that's the answer I was looking for.  I thought about the ramifications of having the cover opened up and all kinds of nasty stuff getting in there, but if it was going to make the header removal a LOT easier to deal with it would have been worth it.  If it's not going to make much difference, then it doesn't make sense like you said.

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 Posted: 09-10-2014 04:31 pm
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answerman
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gmgiltd wrote: Just spent the last few days doing a similar job. UK spec does not have the complication of the steering column and I was re-installing my Lotusbit's reconditioned cylinder head.
It's a lot easier with the cam housing removed so if you need to shim the valve clearances it makes sense to combine the work.
Didn't plan on going that far, but thanks for the input.  At this point I'm not messing with the engine any more than I need to since I'm overall happy with the way she's running.

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 Posted: 09-10-2014 08:53 pm
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Jensen Healey
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Many a 907 has burned exhaust valves because checking the valve clearances is a pain in the b. Go ahead and remove the covers, check the clearances, and if the exhaust valves need shimming, install the header with the cam tower off.

It's hard and painful, but not impossible to reach the exhaust manifold nuts. I just like to complain!

The copper nuts with the 12mm head are easier to install and well worth the investment.

Kurt

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 Posted: 03-28-2015 05:26 pm
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Pandit
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Hi
I'm also removing the headers. Everything is loose, but there is no space to thake the headers out of the car. What ist to do?

Thank you for the help!


Roland, Switzerland

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 Posted: 03-29-2015 09:31 pm
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Jensen Healey
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I had to cut the broken header into several pieces to get it removed. You can try loosening the motor mount and jacking the engine on the left side.

The new 4 into 1 header installed more easily.

Good luck,
Kurt

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 Posted: 03-29-2015 11:42 pm
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Pandit
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Thank you Kurt, I will tray it!

Roland

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 Posted: 03-30-2015 06:54 pm
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Esprit2
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The original steel-asbestos-steel gasket between the header and the head aren't bad, but they do tend to blow over time. The exhaust manifold gasket Lotus used in the later Euro 910 Turbo engine are a triple laminate of stainless steel with no asbestos (they're a lot like the Cometic MLS gaskets). They don't blow, and I've even re-used them multiple times.

The original Euro 910 gasket, and all Federal 910 gasket is a double-laminate. That's what LCU (Lotus Cars USA) sells in North America... they never brought in the upgrade triple laminate. You can get the upgraded triple-laminate gasket from Euro sources, or in the USA, JAE has had an aftermarket triple-laminate stainless steel gasket made. I've used it many times, and it works well.

The difference is that the Lotus version (both double & triple) is crimped together around the perimeter, and the JAE version is riveted together (eyelets) at three points. For some manifolds, one eyelet can interfere, but a little trimming fixes any interference. Once installed, the joint doesn't care of the gasket came crimped, or with eyelets.

The triple-laminate gaskets are much more expensive than the old 907 gaskets, but they last. Removing the manifold with the engine in the car is a pain, and not having to repeat the job can be worth the higher price of the gaskets. The Lotus OEM gaskets are much more expensive than the JAE gaskets. I'm not certain, but I think SJ Sportscars in England also sells a riveted triple-laminate gasket similar to JAE's, and they may even get it from JAE. Check with Steve.

Last edited on 03-30-2015 07:01 pm by Esprit2

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 Posted: 03-30-2015 07:07 pm
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Esprit2
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Loosening the left engine mount, and jacking up the left side of the engine will both raise the engine, and rotate it to the right (ie, it pivots about the right mount). But you can only go so far before the bell housing or transmission binds against the body.

Also, the gear lever can bind against the side of the hole through the body/ transmission tunnel. If you elect to raise/ rotate the engine, first either remove the gear lever, or select a gear in the far left gate to move the lever as far out of the way as possible. Then pay attention to the gear lever as you jack the engine, and don't put any force into it by binding it against the body.

Last edited on 03-30-2015 07:09 pm by Esprit2

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 Posted: 04-25-2015 07:26 pm
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Pandit
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The header is now in position and tighten. I hade to change the engine mount because I did a stupide work. (Jack the engine without loosing the mount) The exhaust is nearly in positon but it touch the rear axle. What is wrong? The mountig laches are in the correct position. (see pictures)
Does it need a clamp between header and exhaust? (first picture)
Yes, there will come rubberparts to mount the exhaust!

Thank you for help!









Roland


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 Posted: 04-27-2015 02:19 pm
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gmgiltd
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Hi Roland,
No idea who you got the exhaust from but it's not in the standard configuration which was two 1.75" pipes over the axle. Mines not standard either and was fabricated from 2.5" 304 stainless. It's hard to explain but from the bracket under the seat it needs to go up at an angle towards the outside of the car, then straight back over the axle, then down towards the car centreline, then straight back to the silencer. I used Jetex short elbows which are available in mild or stainless steel from 1.75 to 3.0" - if you can't find them locally try Merlin Motorsport.
From the photos yours looks like the front need to be shortened by about 20mm and the rear section over the axle re fabricated.
Best of luck
Gordon

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