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Whould somebody please explain what a "Map Clamp" is. I really have no idea what it is and what it does. Is this something you can buy?

Thanks for your help...
 

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Lazy people. Simply a Mapclamp "Hides" boost from your PCM. It prevents the PCM from pulling timeing and fuel based on what it thinks is overboost.

Yes you can buy one, But if you install one you need a "Wideband" which is basically a very accurate O2 sensor wired to a gauge so you can tell what your Air Fuel Ratio (AFR) is. Dyno's have widebands normally or you buy one and install it in your car so you can see what your AFR is on the fly.
 

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Discussion Starter #6 (Edited)
horizon1015 said:
Lazy people. Simply a Mapclamp "Hides" boost from your PCM. It prevents the PCM from pulling timeing and fuel based on what it thinks is overboost.

Yes you can buy one, But if you install one you need a "Wideband" which is basically a very accurate O2 sensor wired to a gauge so you can tell what your Air Fuel Ratio (AFR) is. Dyno's have widebands normally or you buy one and install it in your car so you can see what your AFR is on the fly.
Thanks horizon105. I did do a search, but found nothing explaining what it is. BTW, I take it your an SP? I'm a Tech @ Edwards.
 

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=map clamp




i got my map from staples and it works with my laptop and i got the c-clamp from homedepot. if you pick up both of these it'll work great, so far so good with mine.
 

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Uncommon, you have way too much time on your hands. jcodol, The world is way to small, Yes I SP im just in Kosovo right now. I've been to Edwards many a time's home is Santa Clarita.
 

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uncommon said:
+
=map clamp




i got my map from staples and it works with my laptop and i got the c-clamp from homedepot. if you pick up both of these it'll work great, so far so good with mine.
:jester: :jester:
 

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fusion said:
Boohoo, we are the elite srtforums, and it is below us to help any noobies. Assholes.

As always, thanks to Exhaust Depot for the good info.

http://www.exhaustdepot.net/pibaco101.html



Just look for the "What is a CLAMP?" section.

i'm not being an asshole. all he had to do was search, obviously he didn't. there has got to be a gazillion threads on map clamps.


and also, how is he a noobie? he's been on here since December of 04....? :stab:
 

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Technically it's a zener diode, and if you want to get fancy and make it adjustable you can add a potentiometer (variable resistor). It gets wired into your factory engine wiring harness going to the MAP sensor (which is located on the intake manifold). The MAP sensor is used by the PCM to tell how much boost and subsequently air is going into the engine. Combined with knowing the rpm's and other sensor readings the PCM can determine how much fuel is needed. The MAP clamp then "clamps" or limits the maximum voltage (and boost) that the PCM will see. And if the PCM only sees 15 psi of boost and you've manually turned it up to 17 psi, you'll still only get 15 psi worth of fuel which will lean the air/fuel mixture out.

Check out the "sticky's" at the top of the tuning section. You should be able to find a lot of other information on what it does and how it works. Like a lot of performance parts and modification it has advantages but also some pretty big risks if you're not careful and don't know what it's doing.
 

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blackbird_R/T said:
Technically it's a zener diode, and if you want to get fancy and make it adjustable you can add a potentiometer (variable resistor). It gets wired into your factory engine wiring harness going to the MAP sensor (which is located on the intake manifold). The MAP sensor is used by the PCM to tell how much boost and subsequently air is going into the engine. Combined with knowing the rpm's and other sensor readings the PCM can determine how much fuel is needed. The MAP clamp then "clamps" or limits the maximum voltage (and boost) that the PCM will see. And if the PCM only sees 15 psi of boost and you've manually turned it up to 17 psi, you'll still only get 15 psi worth of fuel which will lean the air/fuel mixture out.

Check out the "sticky's" at the top of the tuning section. You should be able to find a lot of other information on what it does and how it works. Like a lot of performance parts and modification it has advantages but also some pretty big risks if you're not careful and don't know what it's doing.
what he said. And ive got one for sale if you want it, 20 bucks shipped :thumbsup:
 

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uncommon said:
i'm not being an asshole. all he had to do was search, obviously he didn't. there has got to be a gazillion threads on map clamps.


and also, how is he a noobie? he's been on here since December of 04....? :stab:
First off, he claims he searched, and while it is impossible to prove he did or didn't, I'll give the benefit of the doubt to a veteran. If he doesn't know what a map clamp is, then that gives relative noob status, since every method of fuel control uses some form of map clamping (aside from standalones and staged computers). How are you not being an asshole? You obviously took offense to the statement despite the fact I mentioned no names. So if you weren't being one, why are you replying? Oh right, cause your post was useless. Nice. Still funny though.
 

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MAP clamp = one set point where you get no more fuel afterwards, where as a S-AFC or other piggyback can can progressively or linearly hide more or less boost from the PCM depending on what rpm range you're at, how much boost there is, etc. An example would be that a piggyback could take out 10% of the fuel between 3-4k rpm's, 8% fuel between 4-5k rpm's, 13% between 5-6k, and so on. Or it could be set up "load based" so that it takes away 15% of the fuel when the MAP sensor gets to 3.2-3.6 volts (which equals a certain boost range), 17% between 3.61-3.9 volts, etc.

With a MAP clamp you just get leaner and leaner the more boost you run after hitting the clamp point. If your MAP clamp is set to 4.3 volts lets say that equals 15 psi. The computer will run and see boost exactly like stock up until it hits 4.3 volts. After that point if boost continued to go up the computer will still only see 4.3V and provide fuel for 15 psi of boost, even if you're running 16, 17, 18 psi or more.

They're both tools that trick the factory PCM by altering the signal coming off the MAP sensor, just that one works like a sledge hammer (clamp) and the other is a more precise, delicate jewelers screwdriver better for fine tuning (piggyback).


Answers to 97% of the basic questions can be found here:
http://www.srtforums.com/forums/showthread.php?t=177390
 

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Sorry folks but does it really hurt to ask a common question over again?

It is easier to ask than to waste time searching sometimes.

If people are eager to give their advice again, there is no loss. Why do some get mad and then waste time responding with name calling and such? If you don't want to respond just skip the question!
 
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