OBX header install

[secondchance]

WAZOO gang helped me install a set of OBX headers last Saturday at WAZOO headquarter at Westminster, MD.
Headers were Jet-coated prior to install. Before the install, after the removal of the exhaust, I lined areas adjacent to headers (around the bell housing) with "Megamat" I had purchased at Ebay - about 1/16" adhesive backed foam/aluminum foil. This stuff sticks! After a quick wipe down w/ 409, I cut pieces of this mat and stuck it to the hump as high as I could get it.
Passenger side where we typically needed to extend connector for the O2 sensor was not necessary since OBX collector is about 10" forward of SSW version. We found knock sensor wire was cooked and broken so the cut was repaired and new flex conduit was used to cover all wires on both sides and secured away from the headers w/ zip-ties.
Headers went on without a drama but needed a persuation from Jim's hydraulic "jaws of life" to push the slip connection of the exhaust on the passenger side.
I kept my 94 factory exhaust minus the cats and the resulting sound is exactly what I was hoping for since I prefer relatively quiet exhaust at cruise. It sounds a shade louder at idle but not much. However, as the throttle is pushed you start to hear a growl starting around 2000 rpm and progressively louder as the rpm climb. The growl is not as raspy as Corsa but more mellow sound. Also, hp and torque gain can be felt through the entire rev range. I can definately feel the improved throttle response.
It was interesting to feel the difference in trans hump temperture between where I had lined vs. left alone. I think I will line the balance of trans hump the next time I get her on the lift.
I am running a borrowed 94 stock memcal while mine is being reprogrammed by Marc. It was intersting that for the first 30 miles or so the ECM was triggering the "check engine" light. After a while this stopped. It may be ECM was reading a sudden change in fuel mixture/O2 reading and eventually learned new parameter.
I am expecting a new memcal in next 2-3 days and we shall see how the ECM respond to new calibration.
Jim took a few pics (not a lot - too busy with the install) and when I get them I will post them.
OBX is a quality product and no unusual rigging was needed for install at bargain price, especially in my case (- I know, Bob, I know...).
Thanks to all WAZOO gang for the procurement, install and company.

[Scrrem]

Great news and good write-up. Did you get all the bolts in and did you have to take a grinder to Jim's 8mm?
Rich

[mgbrv8]

I agree secondchance my OBXs went on with out a hitch, except I had to rebend my dipstick tube. Did you put in all 32 bolts in? I did, I used stainless allen head bolts, some of them were really hard to get back in I see why the factory didnt put them all in. I love the sound of course mine is louder cause I have a flow master exhaust. But it sounds really good, I haven't been around to many ZR1s so I have nothing to compair it to. It has a great ideal nice and mellow and as you start to go through the revrange it has a great tuned muscle car sound and them it morphs into a exotic kinda ferrari sound. Needless to say I am very pleased. The build quality is excellent also.

Dave

[secondchance]

Shhh! Phil might hear - only got 13 each side. 2 each side on my heads were dowels cast into the heads. I might get the others later. I might borrow your special box wrench for that.

Mgbrb8,
Paul Workman sent me a custom dip tube mount relocation bracket. I thought you knew this piece was available.

[richard sanderson]

I agree with all these above comments. My new headers were fitted pretty straightforwardly, and we now have all 32 bolts installed. We did not do anything about coating or heat matting - do we risk cooking something?
Cheers from sunny Spain, Dick

[tomtom72]

Originally Posted by richard sanderson

I agree with all these above comments. My new headers were fitted pretty straightforwardly, and we now have all 32 bolts installed. We did not do anything about coating or heat matting - do we risk cooking something?
Cheers from sunny Spain, Dick

Rich, here's the thing about ceramic heat barrier coatings. Stainless is a great transmitter of heat, it does so very quickly. The OE system had heat shields which I'm sure worked to keep the heat from building up over time to the point where the insulation on the harness wires gets brittle from that heat. In place of heat shielding, typically you ceramic coat headers to keep that radiated heat down for the sake of the wires' insulation versus cooking that stuff over time.

As a bonus, the ceramic coating keeping the heat inside the exhaust tubing serves to keep the heat energy in the gas stream which helps keep the gas stream velocity high so it leaves the system in a timely manner. If the gas stream cools too quickly it will slow down and I guess back things up a bit...not too sure on that point, but I do know that a hot gas will have more energy than a gas that cools quickly. Stainless just transmits heat too quickly, it has no moderating characteristics like steel or cast iron.

Oh, the ceramic coatings that actually do something like keeping the heat inside the tubing are fairly ugly in appearance but they transmit less heat to the motor compartment. I guess ya can't have everything.


Tom

[HAWAIIZR-1]

I'm with Tom and would highly recommend ceramic coating by Swain Tech or Jet Hot, etc. and least preferred method to wrap them. Mine were done by Jet Hot and they did the inside too for what its worth. I heard a lot of good things about Swain Tech after getting mine done. I like the chrome look of the Jet Hot over the white from Swain Tech with prints and stains. Sucks being a waxer and choosing looks over function all the time.

[sammy]

just double ck your o2 sensor wires and make sure they are out of the way .

[HAWAIIZR-1]

Thanks for sharing and always good to hear product reviews.

[Paul in VA]

Hi Secondchance:

I am very interested in the long term viability of the Megamat. I read their sales information and they mention that Megamat is good to 300 degrees. In one place it says that it may be used underhood and on firewalls. In another place they seem to caveat that with the 300 degree comment. Nowhere do they talk about it's use on the outside/underside of a car. All of their pictures seem to be on the inside of the car. If this stuff works, I want to do my car too! It is exactly what I am looking for.