MAF sizing - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

TwinPiston · 07-07-2003, 16:42

Who on the forums has actually measured the in side diameter of there MAF??? I did this last night as I am in the mioddle of polishing a few pieces under the bonnet and noticed that at its skinniest point it is approx 73mm-75mm. This is on an AUII XR8.

Cheers

Corey

ebxr8240 · 07-07-2003, 17:58

Think thats bad pre A.U's are 50mm..

blueoval · 07-07-2003, 18:16

Yeah I wouldnt be suprised if mine is less than 50mm. Is there a way of increasing the housing or making up another aftermarket one to suit the sensor?

TwinPiston · 07-07-2003, 20:59

they can be bored out a little, which is what I am going to do to mine as well as have the TB bored out as it is only a 65mm, and then have a new butterfly made up. I don't know about making a new housing, that could be a little risky and may be dearer than just buying an AU one.

blueoval · 07-07-2003, 21:21

What kind of place bores out MAF's like this?

EDXR8 · 07-08-2003, 00:52

Don't bother getting the MAF or throttle body bored. If you bore the MAF you will just make the engine run lean, you can correct that by upping the fuel pressure, but it is much easier just to get a C&L or similar MAF if you need. 70mm MAF should easily be enough for 250+kw. Also the 65mm Throttle body is more than enough for around 300kw. Increasing it's size can actually result in a decrease in performance due to lower air velocity.

BlownV8 · 07-08-2003, 16:29

Quote:

Originally Posted by EDXR8

Don't bother getting the MAF or throttle body bored. If you bore the MAF you will just make the engine run lean, you can correct that by upping the fuel pressure, but it is much easier just to get a C&L or similar MAF if you need. 70mm MAF should easily be enough for 250+kw. Also the 65mm Throttle body is more than enough for around 300kw. Increasing it's size can actually result in a decrease in performance due to lower air velocity.

I totally agree, if you bore a MAF sensor, they become inacurate, they measure the air flow Vs the diameter of the housing. They are programmed to calculate on a set diameter eg 50mm. If you increase that, the sensor will not give acurate readings. ie poor idle, lazy throttle response, and possibly pinging in the top end.
If you really want a bigger TB, go to VPW, they do TB's up to 85mm for about $350, comes with TPS attached.

blueoval · 07-08-2003, 17:06

thanks guys, I was looking at more a bigger MAF. I could get a 70mm MAF housing and 24lb injectors for mustang 89-93 from Wayne Phillis Ford for $950. Would that be the better way to go?

BlownV8 · 07-08-2003, 17:43

Just another little idea that i do not see a lot of on here, but $1000 buys a dry nos forgger system. Using a 50 or 75 hp shot, you would get a hell of a lot more go for your money. Yes i am aware of the dangers of NOS on std engines, but i know a guy that ran a 150 shot on a std el futura 5.0, and has never had a problem, and this guys nearly always has it permanetly switched on.

Just another idea you guys might want to consider

blueoval · 07-08-2003, 18:24

Is that legal BlownV8? I thought it was ilegal to use that on the street and also I thought that having it connected can be ilegal too. I'm not sure, what do you think?