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Integrator
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Discussion Starter · #1 ·
Has anyone installed Alunox header with engine in situ?

Any tips/observations would be appreciated.
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1983 Turbo Esprit
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On a G car yes. It took about 24 hours off and on and lots of four letter words. Are you doing a Stevens body??? If not I will walk you through the bleeding and what it took. If you are doing a complete exhaust system with a catalyst there is an whole other issue if using Alunox supplied 3 inch exhaust. Vivian had his daughter weld in a custom made exhaust system. The lower tub on North American cars is different then the ROW cars without catalyst. One thing to keep in mind is the oem header is notched out and some of the nuts are hidden. 1/8 and 1/4 turn backing off with custom "adjusted" wrenches to fit in. Also lots of heat three times with a banging device and penetration oil. Some nuts will not come off until the manifold is moved away from the head. New nuts will have a 12mm size and easier to work with on the reinstall instead of the 13mm. RDENT and JAE both have them in stock. We also used them on my sons Jensen Healey, although they had a factory header and easier to work with. Wrapping the exhaust is no small pleasure either and extra set of small hands come in helpful. Lifting the engine on one side doesn't help either. The blow off valve is a bit of a hassle on the G car , again its space and the caution needed to not damage the turbo oil return to the sump. Small hands are certainly an advantage and a ample supply of bandaides. Penelope and I are blood sisters at this point. Pulling the lump is probably faster, easier and you can toss a new belt on at that time :grin2:
OMT,, have ample supplies of the alcohol of your choice nearby.
 

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I just did this on the '95 s4 with engine in place.

After lots of expletives I tried another idea: here was the trick: undo the engine mount on the same side as headers, lift the engine slightly. Also pre-bolt the old manifold to the allunox to align them first, and then carefully move to the engine. It went on really easy after those two steps...
 

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Integrator
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Discussion Starter · #5 ·
I just did this on the '95 s4 with engine in place.

After lots of expletives I tried another idea: here was the trick: undo the engine mount on the same side as headers, lift the engine slightly. Also pre-bolt the old manifold to the allunox to align them first, and then carefully move to the engine. It went on really easy after those two steps...
Brilliant idea! Never thought about lifting the engine!
 

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I did it to my 1990 Turbo SE with engine in place. No problem. No need to remove anything, apart from the heat shields around the left hand side engine mount, and I also took off the turbo for ease of lifting the old heavy cast iron manifold out.
Do yourself a BIG favour and order the high spec heat grade K-nuts, which is the light grey'ish ones, not the normal looking ones, as those are lower heat spec. And get them for the turbo to manifold as well. They are super strong, takes up less pace and makes more room for future ease of installation. And they won't move. No need for all sorts of locking plates, wires and what not.
To loosen the original nuts, I grinded down a bit on the outer edges on a slim spanner of quality steel, and both working from above, sitting in the rear luggage compartment, and sitting on a box in the pit, with my back towards the front of the car, I could loosen the original nuts enough a little bit at a time, around 1/8'th of a turn, to finally take them off. Some cannot come off unless you have loosened other ones. Look at where you will work and then work in blindness by placing the spanner on the nut, move it 1/8'th of a turb, take it off, flip it and then back on and turn. Take the arm down once in a while to get fresh blood circulation ;) Then jump inthe trunk and repeat. I used no gloves to better feel what I was doing, as I couldn't see the places I was working on. But no preblem, really. Look at the construction thread on The Lotus Forums, at "Little Red Riding Hood". Takes a bit of time to do the whole work, but not so difficult. You may or may not need to send the family out on a long walk in the park, and supply yourself with a thermo can of coffee or tea or maybe a pint of dark ale. Sometimes loud noises resembling swearing or ancient dwarf language can be heard from underneath the car. But overall, not difficult, just a bit tedius.
I took my new alunox system apart and went over the edges to make sure nothing was binding. A bit of slip spray was used as well. Then back to a whole system, then under the car, and on it went. I am not a fan of the support stay. I did not install mine.
Using the new K-nuts, and a smaller spanner, it's a 1,5 hour job to install the turbo and the alunox exhaust manifold. And steel gaskets, not the layered fiber ones.
Remember to insulate the frame tube that is nearest the new exhaust manifold with some flexible heat wrap and a couple of metal ties. No heat damages then.
And remember to make sure that the studs in the cylinderhead is tightened to spex and no damage on threads. I also used 1200 deg cel. wera ceramic anti seize paste.

If nuts or bolts are stuck, I use a mix ½ and ½ of autotransmission oil (red) and acetone in a drip can. Apply and leave for ½ hour, then repeat. It will come loose. I have MUCH better results with that, than all sorts of special sprays and what not. Mine were not stuck, but just a tip.

As others have expressed, I also bolted mine up the the old one, before installing it. That's how I noticed mine was bad out of angle welded on one flange and had to be modified. But overall just making it easier. And you'll notice a big difference, once you drive. And it saves you a lot of weight.

Cheers,
Redfox.
 

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I did my 94 in situ.

My old manifold had been off in the last few years I am sure because the nuts came loose easily.

I removed the rear trunk floor and the turbo, lower engine panel and the heat shields around the engine mount, also the panel in the rear fender well. With the turbo out, I was able to reach from the rear forward to several of the nuts and I think this was worth while. Also, I was able get a 1/4" socket with various wobble extensions and a swivel on all but two or three of the nuts. So I only had to remove a couple a 1/4 turn at a time. Much of the work was blind as Red Fox mentioned.

I would add a caution, it seems to me if you strip one of the old nuts you will not get it off unless the motor is removed. There is simply no room to get any of the tools in there that you would need. If your exh manifold nuts have never been off, plan to remove the motor, and if you dont have to remove the motor consider it a blessing. If you do - you will already be planning so know big deal :)

As has been expressed many times before - the new manifold goes on with smaller nuts, between that and the extra space from a tubular manifold - the on off in the future will be quite simple.
 

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Integrator
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Discussion Starter · #8 · (Edited)
To all:
Thank you for all tips and constructive advice.

What gaskets do you recommend, stainless triple layer sandwich or else?

In addition to Jacques's postings in "Red Riding Hood",(pages 8 & 9), I found other thread on the topic of Alunox header:

Reading trough it could be compared to the best factory manual!

Also, I found another thread on the subject: How to undo the exhaust manifold?
and

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Integrator
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Discussion Starter · #11 · (Edited)
FYI:
For your convenience, here are the most of Alunox header threads in one place:







The latest :

Is this address still good? [email protected]
 

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Integrator
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Discussion Starter · #12 · (Edited)
Degree of pain during installation depends on the header generation and is directly proportional to the length of exhaust studs. OEM studs have length of ~45mm and they stick out of the head ~29mm. That is considered "long" stud and requires lifting engine 1-2" off the engine mounts to clear #2 primary tube interference to the chassis (and some other problems). Probably, because of this, Gary Kemp sells shorter 41mm stud sets.

If you stay with longer studs, make sure that none backed off during OE cast header removal (re-tighten all as a precaution).
Aligning header holes simultaneously over 12 studs is difficult. To make it easier, you may add a smooth chamfer to all holes. At least I did, it works.

"Early" headers with stamped conical transition sections have a relatively easy access to all upper studs.
However, the later CNC cut version has pockets milled into the CNC flange collar. "Long" studs will interfere with the pocket-to-collar transition making ring spanners useless in the final nut torquing. Only a specially modified angle spanner can do the job.
13mm hex head nuts supplied with the kit are impossible to use at the upper stud location. K-nuts (10mm hex heads) are the only solution to the clearance problem.
Bottom nuts can be driven with ratcheting spanners and 1/4" drive sockets relatively easy.
 

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Integrator
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Discussion Starter · #13 ·
REMOVING TURBO NUTS

My turbo flange was held by 12mm hex head K-nuts. To remove two outboard nuts, a special ring spanner had to be made. DO NOT even think about using an open wrench. Soak it overnight with Kroil or Superzilla penetrating oil. Forget WD40!
Take Craftsman wrench to a bench grinder and thin out the ring OD and reduce the height.
Inboard nuts can be accessed much easier upon removal of the Compressor housing.
 

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Integrator
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Discussion Starter · #14 ·
ALUNOX TURBO FLANGE BOLTS

Before
attempt to install new header, check for bolt interference. Two forward bolts can not be inserted and their holes have to be slightly enlarged. Bolts sent with the kit are made of 304 stainless, which is relatively soft. I'm always concerned about rounding off Allen socket heads in the future, thus I prefer 12-point bolts in tight locations. Found that ARP 672-1005 Black Oxide Bolts fit this application quite well. Also, smaller (12mm) K-jet nuts from DemonTweeks, UK, are easier to operate than 13mm hex nuts supplied w/kit. With K-nuts you don't need to use the "bent tab" strips.

40mm bolts are tad too long, therefore try a "dry fit" to find out if you have enough of the bolt tip-to- turbine clearance to be able to withdraw your (grinder modified) ring spanner after final torquing of the nuts. Add washers under head of the bolt, as needed..
 

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The k-nuts keep the nuts from backing off, but not the studs from backing out if the head. I'd still recommend the retaining tabs.
 
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Integrator
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Discussion Starter · #16 · (Edited)
FYI: Alunox header turbo flange sits higher and closer to the head than OEM.
That creates a few problems.
There is an interference of the water inlet fitting to heat shield, which prevents proper clocking of the CHRA. To mitigate this condition I have replaced 6mm spacers behind the shield with 3mm parts (red), rounded off top of the fitting and ground off ~ 5mm sliver off the Alunox strut mounting bracket.
Also, one of the strut mounting "ears" needs trimming.
 

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Integrator
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Discussion Starter · #17 · (Edited)
TURBINE INLET FLANGE GASKET (MIS) FIT

First pic shows my old OE steel gasket overlayed over Alunox header flange. The center opening is flush with edges of the flange opening allowing for a full flow.
The composite (silver) gasket sent with the header has a smaller opening (by 3mm per side). This would hinder exhaust gas flow. NG!
Next, I bought a handful of stainless gaskets, all advertised as "T3". Unfortunately, none had an opening as large as the old gasket, pic 3.
Finally, I found on eBay a 4 layer Mamba gasket, which has a proper large opening and fits perfectly. Part number 031-0029.
 

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Integrator
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Discussion Starter · #18 · (Edited)
TURBOCHARGER INSTALLATION

Fasteners sent with the header are not very user friendly. Aerotight nuts are gigantic (17 mm hex) and would be difficult if not impossible to tighten in such a small space. The bolts were soft. A-2 stainless w/Allen recess heads which may round off during future removal attempts.

I decided to use a high grade (12 pt, 12 mm heads) ARP bolts and K-nuts to fasten the turbo. ARP 12 pt bolts provide greater grip, torque capability and easy access for 12 mm standard ring spanners. Kit number is 672-1005.

On the left side, the two nuts require a modified 12 mm ring spanner (ground thin and slim). Open end spanners may be used, but not for final torquing. Best access is from the side trough the wheel well.
Special attention has to be given to the bolt protrusion after tightening. If the tip protrudes over the K-nut more than 1 thread, then upon final torquing, the ring spanner may become trapped between the bolt and the housing. Bolt height may be controlled by adding shims under the head of the bolt.
 

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