1992Lexus.. Complete build thread with pictures and links!
#841
Lexus Test Driver
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Ask LexusFTW IIRC he had one .
I am using a GM 3bar works great.
Or get the AEM3.5 those are not too exepnsive.
#842
1JZ Single SC400
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About the map sensor, I was under the impression that the stock one will be just fine with my application. Why do I need a larger one??
I will be back tomorrow to fix oil leak, install exhaust, tidy up some wiring issues for the injectors, and start putting the bumper back on...
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#845
1JZ Single SC400
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Cartmill, I believe someone told me that 1 bar equalled around 17 psi. So if the stock map sensor that I am using is 2.3, then I could run around 35 psi of boost. is this correct? I may have forgotten the correct info. It may be in the 4200 page of this thread somewhere. lol
#847
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MAP sensors measure absolute pressure. Boost sensors or gauges measure the amount of pressure above a set absolute pressure. That set absolute pressure is usually 1 atmosphere (1 atm) or 14.7 psi. This is commonly referred to as gauge pressure. Boost pressure is relative to absolute pressure - as one increases or decreases, so does the other. It is a one-to-one relationship with an offset of -14.7 psi for boost pressure. Thus a MAP sensor will always read 14.7 psi more than a boost sensor measuring the same conditions. A MAP sensor will never display a negative reading because it is measuring absolute pressure, where zero is the total absence of pressure (it is possible to have conditions where negative absolute pressure can be observed, but none of those conditions occur in the air intake of an internal combustion engine). Boost sensors can display negative readings, indicating vacuum or suction (a condition of lower pressure than the surrounding atmosphere). In forced induction engines (supercharged or turbocharged), a negative boost reading indicates that the engine is drawing air faster than it is being supplied, creating suction. This is often called vacuum pressure when referring to internal combustion engines.
In short: most boost sensors will read 14.7 psi less than a MAP sensor reads. One can convert boost to MAP by adding 14.7 psi. One can convert from MAP to boost by subtracting 14.7 psi.
In short: most boost sensors will read 14.7 psi less than a MAP sensor reads. One can convert boost to MAP by adding 14.7 psi. One can convert from MAP to boost by subtracting 14.7 psi.
#851
1JZ Single SC400
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Update..... Cartmill just left from street tuning. We have it pretty darn close... My thanks goes out to him for sticking with me.. Its almost a 2 hour drive one way from his house to mine... :-)
Drove around the city and highway for about 25 miles or so.. Everything went well. The metal o clip on the tranny is hitting the driveshaft. I remember it got bent somehow.. The oil leak is the driver side valve cover.. Its pouring oil.. I hope the 2JZ valve cover gasket are the same... Need to charge the AC.. Finish up some loose wiring under the passenger side floor board, and drive it to Atlanta.
As soon as we pulled up at Chevron, two guys in a old Honda Civic hatchback got out and went straight over to the car and said, "What kind of power are you putting down.... Oh nevermind, its a Borg Worner.. Alot " We just smiled...
Will be working on the car all day tomorrow and hopefully get alot done.. Will post more pictures up later...
Drove around the city and highway for about 25 miles or so.. Everything went well. The metal o clip on the tranny is hitting the driveshaft. I remember it got bent somehow.. The oil leak is the driver side valve cover.. Its pouring oil.. I hope the 2JZ valve cover gasket are the same... Need to charge the AC.. Finish up some loose wiring under the passenger side floor board, and drive it to Atlanta.
As soon as we pulled up at Chevron, two guys in a old Honda Civic hatchback got out and went straight over to the car and said, "What kind of power are you putting down.... Oh nevermind, its a Borg Worner.. Alot " We just smiled...
Will be working on the car all day tomorrow and hopefully get alot done.. Will post more pictures up later...