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T.H.O.R. VS Spectre

im assuming tha the CARB sticker allows the modification of some of the vacuum lines necassary to run this kit while still being able to pass smog? never dealt with CARB stickers before. i really want to get rid of my airbox
I'd imagine that the CARB sticker would apply only as the kit is shipped. If it requires modification to vacuum tubes, they got that approved. If you're supposed to just move the tubes over to the new intake, then I wouldn't risk changing anything.
 
You will need to put the CARB sticker on the air cleaner or it will fail the visual portion of the inspection.

And before someone twangs me for being in Colorado and spouting off about California rules and regs... I grew up in California and had the rare privilege of watching the evolution of the emission standards. From nothing to what we have today.

It has been California that has pushed everyone else to reduce emissions. And I, for one, do not miss being behind someone with a worn out engine equipped with a "draft tube".

Watch movies from the 50s. See the fume of white coming out from under the engine? Oil fumes. The ones that are now sucked back into the engine and burned off.

Yup, the crankcase used to be vented directly to atmosphere. By a tube. Pointed down. With a balogna slice on the end. Any blow by was vented out along with normal oil vapors.
I love my 73 Ford, but I intend to install a cat if I keep it much longer. Clean it up some cuz it smells RICH!
 
Update my Spectre Intake...

Got it installed and boy is it loud at start-up... not sure I like it or if I'll keep it. I wanted to install this more to clean up the engine bay and give more room at the front drivers side... but it's very annoying while driving. I'll have to shoot a quick vid and post it up especially at start-up. I've had 3 different passengers in my XJ since installing this and they all got this horrid look on their face and asked me "what is that?!?!" when I fired up my rig. Ha...

Here's a few pics installed. Spectre is supposed to be sending me the SS Vacuum hose to replace this cheap rubber line they supplied, but that has yet to arrive so we'll see.

Spectre9948installed.jpg


Spectre9948installed2.jpg


Spectre9948installed3.jpg


(Note I had to relocate the light attached to the hood about 6" over otherwise it hits the Spectre Pipe. That is something that should be mentioned in the install instructions I'd say...

One thing I'm thinking... the Passenger Side Cowl area is totally closed off from above... and I'm wondering if anyone has ever drilled a hole or opened up that side to allow more air in? Should I be worried about rain getting in or should it drain out the side like the drivers side does?
 
The light is probably rare enough they either didn't know about it or figured it wouldn't be an issue. I know my XJ doesn't have the underhood light.
 
I have the connector dangling, does that count?

Noise wise, how does it compare to the normal CAI open filter? For the first 30 seconds or so, it sounds like an industrial vacuum cleaner is under my hood... Then it drops of to just noisy.

You would have to expect more cabin noise as the filter is now located pretty much directly over the HVAC air intake in the cowl. I, for one, would not cut the sheet metal over the HVAC inlet as water infiltration would, I believe, become more of an issue than it all ready is on the late models.

And, before someone jumps up to point out the filter is under the hood... The inlet is less than 3"-4" from the HVAC opening. I am wondering if another 90 pointing the filter inlet towards the driver's side would reduce the in cabin noise.
 
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It sounds like an Industrial Vacuum is on my passenger side floorboard (inside the cabin).

I'm thinking of opening up the passenger side cowl and putting some noise insulation in the cowl area / firewall outside to see if that helps. I don't expect it to be OE Quiet, but I think the extra noise is almost too much as-is & I'm seriously thinking about putting the OE air box back in. We shall see.
 
It sounds like an Industrial Vacuum is on my passenger side floorboard (inside the cabin).

I'm thinking of opening up the passenger side cowl and putting some noise insulation in the cowl area / firewall outside to see if that helps. I don't expect it to be OE Quiet, but I think the extra noise is almost too much as-is & I'm seriously thinking about putting the OE air box back in. We shall see.

The Cowl drains from both sides where the fender meets the cowl. I should think that any interference with that would promote water infiltration.

What if... a 90* bend was added to point the intake away (and up) from the HVAC inlet?

The noise level is the only reason I am holding back on installing a Spectre as I really need room under the hood for other stuff. If I can get to be about the same Db level as my current (Spectre) open filter, I would jump on it.
 
The Cowl drains from both sides where the fender meets the cowl. I should think that any interference with that would promote water infiltration.

What if... a 90* bend was added to point the intake away (and up) from the HVAC inlet?

The noise level is the only reason I am holding back on installing a Spectre as I really need room under the hood for other stuff. If I can get to be about the same Db level as my current (Spectre) open filter, I would jump on it.

Not sure how you'd attach a 90 degree bend to angle the hole drilled in the firewall away f/the 'dash' area. I'm also not sure how drilling out the cowl sheet metal would interfere w/the draining of water/rain since I'd not be drilling holes in the 'base' part, just the 'top' part. Really hard to explain and I didn't take any pics.

I really think removing that top part of sheet metal, opening up the plastic 'holes' in the cowl (on the passenger side) and then adding some sound insulation material on the metal (say roofers mat) and that would help a lot. I'll have to see if I can find some pics as I have seen this done before on a home-brew kit someone made.


Found the link that has some pics. This is for reference on cutting the cowl sheet metal. I would also plan to cut/drill holes on the plastic to allow for more air to come in via that way... and of course this would also allow rain/water to enter. However I think after cutting this sheet metal out I'd poor some water down to see how it drains before cutting/drilling holes in the plastic. Just to verify it drains and such.

http://ericsxj.com/intake/intake.htm
 
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There is no excessive noise in the cabin, other than when you start the car, and when you accelerate at a very specific point in the throttle.

If you sand smooth the spectre intake part that connects to the firewall (use a dremel) and polish the cutout you made, so that all corners are rounded and there are no sharp edges for the air goes against, that noise will diminish even further.

I've seen someone use tape at the connection of the tube to the firewall (from the inside) and that seemed to work well...
 
There is no excessive noise in the cabin, other than when you start the car, and when you accelerate at a very specific point in the throttle.

If you sand smooth the spectre intake part that connects to the firewall (use a dremel) and polish the cutout you made, so that all corners are rounded and there are no sharp edges for the air goes against, that noise will diminish even further.

I've seen someone use tape at the connection of the tube to the firewall (from the inside) and that seemed to work well...

Interesting idea about polishing the cutout on the firewall and the Spectre part. Hadn't thought about that.

I still wonder if it wouldn't get air faster/easier if I were to cut the cowl area and open it up. I wish I had a spare cowl to try it on... ha
 
Great info, subscribing............

I’m looking for a place to put a coolant filter. Instead of moving the air filter into the cowl, I can cut a hole in the cowl for a coolant filter and leave my stock air filter in place.

 
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Been trying to chase down some noises and am having a bunch of new needed repairs pop up so i haven't even installed mine.

when i do i will have two things on my rig that i will have to tell people to watch out for the company if they like it and ask me about it.. (hate having to do that)
 
I tried to get a couple vids to record the sound. It's not very easy to do w/my iPhone but I tried.

I also pulled the the intake off, smoothed out the firewall cut-out and the Spectre inlet tube that attaches to the firewall and it helped. I only had time to smooth out the lower 1/2 of the cut-out and the top 1/2 needs some work, but I noticed what sounds like a lot 'smoother' air flow and less noise. It's still very noticeable on cold startups, but when the engine warms up it's much less noticeable. I will take some more time and work on smoothing out the top 1/2 half of the cut-out and see what that does. I'm still in limbo on whether or not to cut the cowl as I pulled it off yesterday and got my light out and can see where the fresh-air inlet is sitting now for the AC/Heater blower and as had been mentioned here before not sure I want to add any more of a chance for water to get into that area and possibly leak into the passenger side floor.

Here's the sounds clips... first one is a cold morning start up... second one is after the engine was warm, windows down. Both are after I smoothed out the lower 1/2 of the firewall/intake. (hopefully they work)



 
I have made a mess of my point on cutting the cowl...

The HVAC intake sits pretty much directly under where the cut would be. My concern is that water will run into the HVAC. Good news is, that you can alway weld the cut out back in. I did when I attempted a reseal of the HVAC.

An unsuccessful attempt truth be told.

The noise level you posted appears to be no louder than the open element I am running now. As it stands, today, the intake is about all you can hear at cold start...

Very tempting this. Could really use the room under the bonnet.
 
Are you saying you intend to make your own for sale? Is that why you're offering different colors and giving a price?
 
No, where did my post go? I don't like the 3" and cobbled up welded tubing. Just saying that I am going to make my own not out of PVC but out of silicone tubing and elbows. The 3 in is only rated to 450CFM. I don't want the restriction.

Want it to look like this:
http://www.f150online.com/forums/4725383-post21.html

I want to make mine with silicone elbows and tubing, 3 to 4" elbow to 4" tubing and airfilter to 4" into the cowl. Keep it all 4" and not neck down to 3". 4" will have a better flow up to 650CFM.
 
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I want to make mine with silicone elbows and tubing, 3 to 4" elbow to 4" tubing and airfilter to 4" into the cowl. Keep it all 4" and not neck down to 3". 4" will have a better flow up to 650CFM.

The silicone hose is the way to go. Can you make a silicone replacement hose for the stock ducting? I'm fine with my stock air box, but I would like a smooth silicone hose instead of the OE ducting.
 
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