Anyone know the maximum distance a MAF can be located upstream from the TB?

I have a super nice MAF TPI (`86) system that I'm swapping into and older carb'd vehicle...

 

In 1986 GM put the MAF quite a distance from the TB on Trans Ams. What I like to call the "boxes and elbows" intake system. Long distance with plety of turns and changes in intake plumbing shape. Absolutely horrible. If a MAF can work properly in a system like that I don't think it makes much difference how far away you put it. If it's in the engine bay somewhere it'll probably work OK. If you're thinking about putting it in the trunk...... well, I don't know about that, but it might still work.

Near as I can tell the ECM really relies on the MAF under fairly steady-state conditions. All the transitional stuff on and off the throttle is the TPS and engine RPM. So, I would think that even a long run, which would slow the MAF's response slightly wouldn't be a big deal as long as the system is truly sealed between the TB and the MAF.

 

Many thanks for the reply.... Truly appreciated :O}

I was curious because of underhood heat generated by headers, not so efficient cooling, etc.. and the basic operation of the MAF.

Moving it closer to the actual air inlet (cooler/moist air) would make you think that by the time the air got to the TB, it would have changed density and have an ill effect.

I guess that would be nit-picking if you're talking only a matter of 12-16 inches as compared to sticking it in a trunk...lol

 

It's even farther away on the B-Cars and some of the trucks, although they have newer PCMs and rely mostly on S/D with the MAF as a check and trim for low throttle angle operation.