- Thread starter
- #21
And a YouTube video to boot!
What is this coming off intake manifold?
- Thread starter bwatling
- Start date
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fyton2v
SILVER Star
Definitely a hookup for a nitrous boost system. Been thinking of doing that on my 2F.
I went to their web-site….the altitude compensator is a pretty slick idea. The web-site has an english/spanish switch so you can read about the device and how it works. Maybe even print out the base description and throw a copy in with you other FJ40 repair manuals. It is one of those PO modifications that is unique and in my lowly opinion, worth keeping if it is NOT causing issues…..remember, it’s part of the rigs history, part of its story….and that is as valuable as the rig itself.
Be Good, Cheers!
Sounds like a good excuse for the OP to road trip it from NC over to Colorado, too - you know, "for testing".
So, what is that plugged line, and where should it go to?
cruiserkev
3 decades in the same FJ40
I think it's cool and I would keep it if it works like it's supposed to. 
On their web-site and videos, it shows you can remove the plug and install a vacuum gage. I assume it may come with various springs and/or shims to allow tuning and the vacuum gage allows you to set the device for various displacements and carborator arrangements. So at sea level, under part throttle, it’s closed…then as you increase in altitude and Barometric pressure drops, less air available for combustion, thus causing a rich mixture, the thing opens and leans it out, keeping you in a good stoichiometric (14:1) air/fuel range.
Its a pretty neat device…..I think the only thing I would do different is connect the top of it to the air cleaner instead of the screens and filter paper included.
So it's a calibrated, feedback compensated, altitude dependent vacuum leak, positive altitude coefficient type.
Neato!
Neato!
Oh for sure….its a mechanical MAP sensor…and I think I need one just for bragging rights
I think this thing is another 200 MPG carburetor. It cannot possibly properly compensate for altitude unless its operation is known, as well as knowing what altitude its going to be at. I live in Denver and drive into the Rockies regularly. My house is at 5800 feet, and my friends house is at 9500 Feet. I drive over hills that go to 10,500 feet. I do it in my 1981 Chevy truck with a 6 cylinder. It loses power at high altitudes, but, I'm not sure leaning it out in an uncontrolled fashion will help. Its either open or closed, depending on vacuum differential. and as you move the throttle for more power it will open. Will it go wide open, or modulate. It's snake oil guys...
It's a calibrated vacuum leak.
Sounds like OP has a winter project line up characterising that thing 
Downey
SILVER Star
After I read the Marclair information it seemed like it was some kind of snake medicine since they claim it does everything under the sun ???
- Thread starter
- #34
Well, in follow up I removed it and plugged the hole (thanks for the size @mattressking). No real change in engine sound/running at idle or driving but will go ahead and double check timing/idle now that this likely vacuum leak of some nature is plugged up! I'll keep it around on a shelf for a conversation piece!
