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Originally Posted by supragino
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Originally Posted by CrimsonFury
I got my 94+ tail lights from www.partznet.com. Cheapest place around. Even James at Heffner Lexus toyota (friend of mine) could not get them cheaper even with his discount.
About the blow off valve, unless you have the recirculation kit, it is going to make your car run crappy. The only way you can ever vent blow off to the atmosphere (ie. the pssshhhh sound) is to change over to a map/iat sensor instead of the crappy afm. Because the AFM is before the blow off valve, it will measure X amount of air coming in. The AFM will send a signal to the ecu letting it know that X amount of air is coming in. The computer then decides how much fuel to spray in. It tells the injectors to spray in Y amount of fuel. Now once the air reaches the blow off valve, and if the blow off valve goes off, it releases some of the X amount of air out. Now the amount of air is less, far less. At this point its too late, the computer has already told the injectors to spray in a larger amount of fuel. This creates very bad air fuel mixture and causes bogging, stalling etc.
I can't seem to get the website to work either. They must be out of business or their site is down. |
Well not really bout that BOV...cuz on the supras they do the exact same thing...they reserculate it after the AFM...all u have to do is close off the pipe where the hole is after the AFM and you should be fine...my car works great still...and on stock BOVs they have a sick fluttering sound...hehehe...but remember, that the stock BOVs can only withstand a certain amount of boost, and when u up boost to a certain point, change teh BOV |
Sorry you are wrong about both points.
With the AFM in place the air is metered before the blow off valve. Now in a stock situation its ok. When the air is metered and the signal sent to the ecu the ecu detremines the amount of fuel to spray in (to match the amount of air coming in), and when the blow off valve opens up, it recirulates the air back into the intake system before the compressor housing. This way it relieves pressure off of the compressor turbine (decreases lag and saves the turbo) and gets the air back into the intake system so that when the injectors decide to spray in the fuel, the volume of air is unchanged. This allows the car to run with consistent air fuel ratios across the rpm range. Now if you vent this air to the atmosphere, it has no way of getting back into the intake system. But now its too late, the injectors are going to spray in a certain amount of air (based off the original metering before the blow off valve). This is because you metered the air before you blew off. Now the ecu has no way to measure the new lowered amount of air volume. So its too late. Now the car will run extremel rich after blow off (just for a split second). This causes bogging, stalling and a loss of performance. I was not talking about the opening in the intake after the afm from venting to the atmosphere. Obviously you would close that hole up. That is common knowledge. Understand?
About the stock blow off valve. I'm not 100% certain what the supra's use, but the stock blow off valve on the MR2 is the best performing blow off valve around. There are 2 types of blow off valves. Ones that use springs to stay shut (most blow off valves) like turbosmart, turbo xs, blitz, greddy, etc. Or Blow off valves that use boost to stay shut (oem mr2, hks super sequential, tial, etc.). These are the nicer units. The bov's that use springs are only good up to like 8 or 9 psi. These are the cheap crappy bov's that blow off just from revving the car. How can a blow off releave pressure from revving the car when barely any boost can be made when revving a car in neutral?? It can't. They are just so weak that they go off from the change in vac to positive pressure. Basically the spring keeps it shut up to around 8 or 9 psi. then when you shift the pressure surge in the intake system exceeds 9 psi and the spring can no longer hold the boost and it blows off. This is not good. The bov's that use boost to stay shut can withstand almost any amount of boost you throw at them. As boost pressure rises, it uses this pressure to keep shut, then when the car changes gears or throttle is let off, the change in pressure to vacuum opens up the valve itself. It does not use a spring to stay shut. This is how the stock system works. The only aftermarket units that are AS GOOD AS STOCK are Tial and HKS super sequential. The only advantage with these units is that they are louder than stock. Thats it. I'm pretty sure the supra uses the same system the mr2 uses.
http://www.mr2oc.com check this out, use the search feature and look for 'OEM blow off valve'