xfi air temp sensor location

[jjump59]

Just wondering where I should put the air temp sensor. Can it go in the intake tube between the air cleaner and the throttle body or does it need to be in the intake behind the throttle body? Thanks

[parsonsj]

Mine is in the air cleaner assembly (ahead of the TB).

jp

[64duece]

I prefer the intake tube.

[GetMore]

Kind of hijacking the thread here, but I'm working on a Ram Jet EFI system, and they don't have a provision for an intake air temp sensor in the manifold. Also, the air cleaner mounts right on the front of the throttle body, so I don't have any real plumbing to insert the sensor into.

Where would you mount the air temp sensor in this case?

[toxicz28]

Also, the air cleaner mounts right on the front of the throttle body, so I don't have any real plumbing to insert the sensor into.

Where would you mount the air temp sensor in this case?

I'd make a cold air setup with 3 1/2" exhaust tubing.
It would serve two purposes, it gets the air filter out from behind the radiator, and it would give you a location to mount the sensor.

[parsonsj]

Where would you mount the air temp sensor in this case?

I'd drill a hole in the air filter base, use a rubber grommet, and fit the IAT sensor to that.

jp

[toxicz28]

I'd drill a hole in the air filter base, use a rubber grommet, and fit the IAT sensor to that.

jp

I don't think this would work for his setup on a ramjet intake. It uses a round single bore TB about 3 5/8" in outer diameter, and he probably has a cone type air filter for it.

[GetMore]

I don't think this would work for his setup on a ramjet intake. It uses a round single bore TB about 3 5/8" in outer diameter, and he probably has a cone type air filter for it.

Right you are!

I think I'll have to make up some kind of tubing to relocate the filter and then install the sensor in there, but in the meantime I'm seriously considering installing the sensor in the back of the manifold. I'm going to be running hydroboost and a 700-R4, so I don't need the 3/8" port on the very back. It's not the ideal placement for the sensor, but I'm thinking it'll be good enough. Maybe.

[toxicz28]

3 1/2" exhaust tubing will work for you.

[parsonsj]

I'm seriously considering installing the sensor in the back of the manifold.

That is considered the better place for the sensor anyway, since that more accurately measures the temp the engine will see. If I had had a 3/8" port in my manifold, that's what I would have done.

jp

[GetMore]

Some advice says not to install in the manifold, because the heat from the valley will raise the temps, and that in the airstream entering the manifold is best because that's what the actual air temp is.

I would think that in the manifold is best, since it is the temp of the air just before it enters the combustion chamber, but I don't know.
The only possible problem with having the sensor on the rear wall of the manifold is that it might be stagnant air and the temp might not be correct. Again, who knows if this is an issue?

I guess I'll just install it in the manifold and then do some testing with a separate temp sensor. If the manifold temps read correctly I'll know that I was worried about nothing.

[parsonsj]

I would think that in the manifold is best, since it is the temp of the air just before it enters the combustion chamber, but I don't know. The only possible problem with having the sensor on the rear wall of the manifold is that it might be stagnant air and the temp might not be correct. Again, who knows if this is an issue?

FAST recommends the IAT in the manifold for just that reason. It more accurately reflects the temp the engine experiences. Ideally, you want to measure the airstream, not a stagnant corner, but I'd be surprised if there were any stagnant areas in the plenum or runners of a tested manifold.

I guess I'll just install it in the manifold and then do some testing with a separate temp sensor. If the manifold temps read correctly I'll know that I was worried about nothing.

Way cool! I love actual data. Please let us know what you find.

jp

[Samckitt]

A guy I work with has a Ramjet engine in an older Pontiac & he made a small bracket to mount the air temp sensor right next to the intake filter.