mustang efi help

[Blingmaster]

where is NHRA rules concerning efi air intake options for 89 fox body? Also any rules concerning placement of mas sensor. Can you just come straight from TB? Any help would be appreciated. For Stock Eliminator...DD

[fordteacherguy]

Can't tell you what is enforced around the nation , but most cold air intake kits have passed tech as long as air inlet comes in at stock location. MAF location unimportant by the rules but I would hesitate getting it too close to the TB. Reversion through a MAF tricks the hot wire into seeing the air twice and computer may deliver more fuel that needed and you will have a tuning nightmare. We usually keep it away as far as we can although stock location has worked fine on my projects.

[GTOMayhem]

Originally Posted by fordteacherguy

Can't tell you what is enforced around the nation , but most cold air intake kits have passed tech as long as air inlet comes in at stock location. MAF location unimportant by the rules but I would hesitate getting it too close to the TB. Reversion through a MAF tricks the hot wire into seeing the air twice and computer may deliver more fuel that needed and you will have a tuning nightmare. We usually keep it away as far as we can although stock location has worked fine on my projects.

Is this reversion an issue just with EFI Mustangs? Or is it a typical problem with most EFI cars?

Rick Thomason
GTOMayhem

[fordteacherguy]

Don't know on other vehicles, I'm not a SME on other brands, but MAFs are dependent on clean one way airflow, Large overlap cams can disrupt MAFs signal at low speeds and resonance can disrupt MAF signals at various speeds, hence why there are few MAF systems on race engines, you typically go speed density.

As with everything in engine development, your results may vary. I do use a MAF system on my Super Stocker and was surprised it worked ok, although the camshaft is on the mild side.

[black88coupe]

Originally Posted by fordteacherguy

I do use a MAF system on my Super Stocker and was surprised it worked ok, although the camshaft is on the mild side.

Isn't the beauty of MAF over SD is that MAF isn't as sensitive to camshaft changes (vacuum) making them a natural for this? Or you can keep stock SD with a chip. Not saying MAF is perfect- just better at dealing with cams that have more duration than stock- like a 5.0 Mustang with the EEC4 system for example.

[fordteacherguy]

Originally Posted by black88coupe

Isn't the beauty of MAF over SD is that MAF isn't as sensitive to camshaft changes (vacuum) making them a natural for this? Or you can keep stock SD with a chip. Not saying MAF is perfect- just better at dealing with cams that have more duration than stock- like a 5.0 Mustang with the EEC4 system for example.

True: MAF systems are more tolerant of airflow changes Cams/heads etc than speed density due to the main fuel calculation is related to the O2 content coming across the sensing element Both systems works if you can get a consistent A/F that meets your needs.. Just that MAF has some quirks that can mess with tuning if you don't know whats going on.