Throttle body opening more than 90 degrees
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From: Southaven, MS (near Memphis, TN)
Throttle body opening more than 90 degrees So.. I heard that the throttle body blade opening a few more degrees over 90* is actually very normal and can make a little more horsepower.
Discuss.
Discuss.
Think about what you just said. You have a round opening. You have a blade in the middle of it. If you go past horizontal you are restricting again by putting the backside of the blade into the way.
like blanco said .. anything above 90 (or below) is going to put a blade surface back in the airstream.
Also consider the TPS signal. It reads in mili-volts. I'm just not sure what would be the consequences, in computer response, if you exceed the max amount (by opening the blade too far).
Also consider the TPS signal. It reads in mili-volts. I'm just not sure what would be the consequences, in computer response, if you exceed the max amount (by opening the blade too far).
Most likely from someone who isn't familiar with most fuel injection systems. Modifying the air valve to allow 95* of opening is a popular thing to do with carbs. It helps the cylinders at the ends of the manifold to get as much air as the center cylinders.
Thread Starter
11 Second Club
iTrader: (32)
Joined: Jan 2006
Posts: 3,701
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From: Southaven, MS (near Memphis, TN)
But, this is straight from a sponsor...
You should be able to open that blade far past 90 with no issue , it is not uncommon to go past 90 a little bit , we intentionally do this so the blade angle matches the air entry angle because the ls1 fbody induction system has the air entering on an angle . I don't see it possible that this can cause the problem you are having
I am not talking about it going up to the sky , but a few degrees past 90 is normal and will make a little bit more hp . That is one of the ways the FRE 91mm tb we sell makes more power than other tbs . I am not going to argue with you about this , we've done over 1000 throttle bodies in the last 5 yrs and you are the first person to ever mention a scenario like this to me.
Last edited by jetlag; Mar 24, 2008 at 04:25 PM.
If you look down the bore of the MAF you can see the air is
coming into the TB from the top and you don't see the throttle
blade edge-on at 90 degrees. A bit over center would be closer
to airflow-parallel.
But TPS over 4.75V will bother the PCM, even if you don't set
a code it can mess up your WOT shift behavior on automatics.
If you want over-center throttle blade angle you have to deal
with that somehow.
coming into the TB from the top and you don't see the throttle
blade edge-on at 90 degrees. A bit over center would be closer
to airflow-parallel.
But TPS over 4.75V will bother the PCM, even if you don't set
a code it can mess up your WOT shift behavior on automatics.
If you want over-center throttle blade angle you have to deal
with that somehow.
