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Discussion Starter #1
Quick question do you use never seize or copper coat when reinstalling exhaust manifold bolts for new headers? Reuse or replace manifold gasket? Thanks, Richard
 

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2005 Elise LSS Saffron Yellow
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1. Always a new gasket for new headers - they won't be exactly the same shape as what you took off.

2. The primary concern for exh manifold bolts/studs is corrosion - all the other bad things that happen derive from that. If it's going into an aluminum head, the clamping loads aren't high. The ideal choice is to change to stainless hardware. A second choice is to go to a high strength steel alloy - much stronger than needed, because these also tend to be high chromium alloys and are thus more corrosion resistant (if not loaded to a structural limit). The high strength steel will be more resistant to galling than most stainless fasteners. Don't forget the alloy of the nuts and any washers - most split lock washers are carbon steel and don't retain their springiness after a few header heat cycles. Automotive OEMs tend toward flanged self-locking nuts in this application with no washer. If they don't 'lock' anymore, replace them.

If clamping force is low enough, you can use long brass nuts with steel studs - Kawasaki did this on two strokes back in the '70s with the specific goal of protecting all the thread on the stud from the environment. It works very well in combination with copper antiseize.

You always want to use an anti-seize compound on these fasteners. Chemistry matters, so you want a different one at the steel-aluminum interface with bolts into the head or putting head studs back in (I use 'silver' permatex in the tube - originally 'Aviation Permatex') from the one at the steel-steel interface (I have a tube of NAPA-branded copper anti-seize for this, but it's just copper particles in an oil base -all brands created equal). There are different recommended anti-seize compounds for stainless fasteners of particular alloys. Because of the high temperatures involved, the chemistry matters more than it does on most things.
 

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Thanks Steelypip, I had looked all over for my anti seize that I had from outdrive rebuild two years ago and Murphy prevailed today as I failed to locate it. I used a little moly knowing that I will need to probably to come back and install new gasket. When I ordered the headers and saw gasket included I incorrectly assumed it was referring to the manifold gasket instead of the doughnut. Unfortunately the local Toyota dealer didn't have one in stock. I cleaned up old one and grey scratch padded it as well as block surface. Good news was all fasteners came apart easily and were dry. All new 8.8 fasteners came with the PPE headers. The engine was built by previous owner and it's been apart more than once so if need be I'll order another gasket and properly anti seize it. I may end up wanting to paint the White Lighting treatment black down the road as well but after a month wait for headers, ECU to come in and today being 60 degrees it was going in today. Tech inspection is in two weeks as well. The fun part will be getting that center top bolt in again. I hung it by wire until level, pushed it horizontally with just enough pressure as I turn the bolt with long reach needle nose to get it started properly. Turning wrenches isn't as much fun as it was when I was younger.
 

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2005 Elise LSS Saffron Yellow
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Glad it worked out for you. I know you'll be back into it before too long (by miles or hours) if you're putting it together for pre-season tech, even if you leave it together all season. I will note, though, that O2 sensors don't play well with header gasket leaks...
 

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If I see any obvious signs of leakage I wouldn't run it. It will get added to parts order list along with all the fluids and plugs I just changed while in there. Still new to the car and learning it thanks to LT and contributors like you, Thanks!
 

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Darren I gained 32hp 12 tq with PPE headers, Silent Touch, CAI and REV 300 tune over the previous Koldfire Tune. To really gain anything you'll need retune plus CAI . Sitting at 258 HP 174 TQ now. Lost weight from OEM muffler and heat shield was impressive.
 

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I would use Anti-sieze or whatever ARP says to use on their bolts, I would get a new gasket and use that copper gasket spray dressing.
 

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What kind of gains can you expect from a header install?
Which Lotus do you have?
Thanks,
Given that the stock (Elise/Exige) headers are pretty efficient, not a lot.

Visit BOE's site and look up header test.
 

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What kind of gains can you expect from a header install?
Which Lotus do you have?
Thanks,
Given that the stock (Elise/Exige) headers are pretty efficient, not a lot.

Visit BOE's site and look up header test.
What are your thoughts on cat elimination or upgraded muffler ?
 

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What are your thoughts on cat elimination or upgraded muffler ?
Still no significant hp, but now you're breaking the law and polluting our air. Haven't I told you that the stock exhaust is pretty efficient?

Get the BOE 200 for a nicer car to drive. Perhaps (I'd bet), they can tune it for headers....

Frankly, if headers really helped, everyone with them would need a tune...
 

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Note that the hp/tq peaks vary from one mfgr to another. Decide if you want more top end or mid range. Unless tracking, I'd go for the other,
 

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2005 Elise LSS Saffron Yellow
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Frankly, if headers really helped, everyone with them would need a tune...
QFT. You can safely presume that Lotus would have done something more exotic with the 2ZZ NA exhaust in some variation if they thought they could get significantly more power out of it than Toyota did. It's really a pretty decent design - you need a supercharger or very extensive modifications to move the VE curve around before the stock header stops working about as well as anything.

Note again that I'm talking about the normally aspirated 2ZZ-GE. Forced draft changes things.
 
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