Intake Tuning Valve

[DannyC]

Can anyone post some info on this. I'd like some idea of how it works or if there is any theoretical way of adjusting it.

I expect it's controlled by the PCM like everything else but I noticed if I take off full throttle several times it's not as noticable as the first time. So I don't know if it's just openning sooner or more gradual.

[cflowers1]

On my Intrepid 3.5, you could adjust it. If found if you set it more open, there seemed to be more torque on hand at lower rpms, but not so much on the upper register. Fun stuff, but better left set factory specs.

[oldcarsrock]

This is the same valve that causes that god-awful whistling noise when I'm cruising along below 1800 RPM right? Do the V-8's not do this? If so, that alone might prompt me to upgrade...

[Samoan Tsunami]

Can anyone post some info on this. I'd like some idea of how it works or if there is any theoretical way of adjusting it.

I expect it's controlled by the PCM like everything else but I noticed if I take off full throttle several times it's not as noticable as the first time. So I don't know if it's just openning sooner or more gradual.

this is what i posted so far....

Throttle Bodies V6 vs Hemi

i didnt see any replies from you on this post, so not sure if you read it....

what more in specific did you want/need to know. also remember theres two valves the intake manifold tuning valve, and the short runner valve. they both have an effect on that "punch" you feel. just at different rpm and gas pedal ranges.

[Jaak]

It's something I wish the V8's had as it would improve their performance as well. Longer runner lengths are better for increased torque at lower rpms. As rpms increase, the benefit disappears, and you need the shorter runner length.

Cool system.

[fnkychkn]

i haven't read anything about the MTV (manifold tuning valve) on 3.5L engines in LX but i did find this in the JS Avenger/Sebring manual:

DESCRIPTION

The valve opens a crossover passage that connects both sides of the intake manifold plenum. It is an electric motor.



OPERATION

The PCM controls the MTV solenoid. The manifold tuning valve optimizes acoustical tuning of the intake system during wide open throttle operation throughout the RPM range to increase torque.


this is the way it used to work on first generation LH ('93-'97 intrepid...):

the MTV optimizes intake manifold tuning throughout all engine operating conditions. at wide open throttle, and engine speeds below 3000 RPM, the PCM controlled MTV closes the passage between the left and right intake plenums. at 3000 RPM, the MTV opens connecting the left and right plenums. at 4300 RPM, the MTV closes and remains closed through all higher engine speeds. this had the result of having two seperate 3 cylinder engines below 3000 and above 4300 RPMs. keep in mind that this version of the 3.5L used twin throttle bodies.

[DannyC]

i didnt see any replies from you on this post, so not sure if you read it....

No I hadn't seen it but was interesting. It said it opens at 5000rpm. Wonder what I'm feeling at 4000? Seems something is really making a difference at that rpm. I was just wonder if something could be done to get it to kick in a little sooner?

[Samoan Tsunami]

No I hadn't seen it but was interesting. It said it opens at 5000rpm. Wonder what I'm feeling at 4000? Seems something is really making a difference at that rpm. I was just wonder if something could be done to get it to kick in a little sooner?

around 3500 i believe that may be the MTV not the SRV. for example, if i need the car to "Get up and go" i dont floor it, but press the pedal about 2/3 to 3/4 of the way down. this is usually when it comes to life.

for me the 2/3-3/4 pedal ordeal is great. mainly cause around 3500-4000 thats about 2/3 of the way to redline. which gives a good "driveable" range for normal driving.

it something i was taught when i first joined SCCA racing, but with manuals you can keep a car in a powerband more efficiently with simply gearing and keeping the rpms up. basically with this car now, i've found that pedal range mentioned above to be what gets into the powerband on the LX 3.5L which means the right amount of air is entering and the computer throws in a decent amount of fuel for that rpm range..hence the power we get during that rpm range.

opening it sooner may lose power overall if the air and fuel isnt sufficient enough.

kinda like as an example, if we switched over to the SRV before 5000, which is good for high end pull, it may kill low end torque.


theres definately probably some better tuning options we could take advantage of, but the more accurate thing would probably be to find out fuel and timing tables at certain rpms and see how things look, ya know brah?


i've been trying to decipher if the dash hawk can monitor things of this nature. if so, i think that it would go perfectly with the upcoming tuner to be released as you can see whats goin on and do a custom tune from there.