Ford Forums banner

MAF sizing

4K views 20 replies 7 participants last post by  blueoval 
#1 ·
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
 
#2 ·
Think thats bad pre A.U's are 50mm..
 
#4 ·
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.
 
#6 ·
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.
 
#7 ·
EDXR8 said:
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.
 
#8 ·
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?
 
#9 ·
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
 
#10 ·
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?
 
#11 ·
No it is not legal. But you can stretch the rules. It is illegal to have a nitrous bottle connected in your car, but it is not iilegal to carry a nos bottle in your car. It is legal to have nitrous connected in your car, as long as there is not supply bottle connected to the system.
SO..........................

Put in the nitrous system, put the supply bottle in the boot, get it painted red with a black stripe ( to look like a fire extinguisher ), and have the supply line tucked out of vision, when you want it on, plumb the supply line in, turn on the tap, and hold on tight. :).

Something else you can consider, althoug more expensive, edlebrock do a plate system for the windsor, that bolts between your block/heads and your intake manifold, and all the plumbing comes out the back of it, impossible to see without removing the engine. You could then use 3 smaller bottles, located under your seat ( not like in fast and furious) on the floor, with a filler valve. This way the whole system can not be seen, and you can fill the bottles without removing them from the car.
I think those plate systems are about $1800, but can save you lots of harrasement from the authorities.
 
#12 ·
Also, this is the ruling in N.S.W. It may be different in adelaide. Check with an engineer. Do not call the R.T.A. or the cops about it, you will never be left alone again.
 
#13 ·
hehe, sounds a little risky mate. But I give credit to those who have done it. I dont think I'll end up going that way. I think the safest route maybe to get the 70mm MAF housing and 24lb injectors and try that from Wayne Phillis.
Hey I reckon it would be awesome to see it used though on the street.
 
#15 ·
I'm not doubting that BlownV8, I would like nothing else better but I'm not into the illegal thing personally. Thats just me. And knowing myself, I know I would use it on the street and get caught!
I find it too risky living in SA. The cops are money hungry down here, there are heaps of RBT's, speed cameras and laser guns. There really is no where to give it a test run on the street here.
 
#16 ·
Thats fair enough, i am looking at running NOS too, but i plan to spend a fair bit of time on the drag strip, so its worth it for me.
Keep us posted as to how you go thou. 302's are a great project for development and modification. :)
 
#17 ·
No probs mate! I agree with ya when it comes to modifying the windsor. Heaps or aftermarket gear for it! I've got a project I'm going to plan in the next 6-12months anyway so the XR8 will have only a few more mods done to it then I'll concentrate on the project.
 
#18 ·
BlownV8 said:
No it is not legal. But you can stretch the rules. It is illegal to have a nitrous bottle connected in your car, but it is not iilegal to carry a nos bottle in your car. It is legal to have nitrous connected in your car, as long as there is not supply bottle connected to the system.
SO..........................

Put in the nitrous system, put the supply bottle in the boot, get it painted red with a black stripe ( to look like a fire extinguisher ), and have the supply line tucked out of vision, when you want it on, plumb the supply line in, turn on the tap, and hold on tight. :).

Something else you can consider, althoug more expensive, edlebrock do a plate system for the windsor, that bolts between your block/heads and your intake manifold, and all the plumbing comes out the back of it, impossible to see without removing the engine. You could then use 3 smaller bottles, located under your seat ( not like in fast and furious) on the floor, with a filler valve. This way the whole system can not be seen, and you can fill the bottles without removing them from the car.
I think those plate systems are about $1800, but can save you lots of harrasement from the authorities.
I dont want to sound like a wet blanket cos I'm really not (I am now and will always be a revhead)... but saying "yep its illegal.. but do it this way and you can avoid harrassment"?? This is just plain bad advice. Fit up your NOS kit and take the bottle out of the car. Easy. If you wanna run with it put it back in and hook it up. Dont have it hooked up 100% of the time in traffic situations. Its not what its for.

If youre still reading thanks.... Something to consider..
1) If you and/or your vehicle is involved in a smash and there is a fatality, the coroner gets your car. Not after youve disconnected the NOS but directly from the accident scene. If your car is found to be unroadworthy you earn a lot of court time explaining why your vehicle was not to blame to a greater extent than just being on the road. Standing in court and saying yep I knew it was illegal but... isnt going to assist you in avoiding a great deal of grief and possibly gaol time if you were at fault in an unroadworthy car (with full knowledge of it).
2) How do explain to a CFS rescue bloke when youre out cold and mangled that he better not cut up your floor pan with the Holmatro gear cos he might slice a NOS cylinder and f^&k himself up nicely in the process.

Sorry about the rant... I run of at the keyboard sometimes... I'm getting on...
 
#19 ·
I 100% agree with tonyk, and do not encourage the usage of NOS on the street 100% of the time, it is a dangerous thing, i was just suggesting ways you can have the stuff in the car if you really want it.
I myself will have the system hooked up, but leave the bottle in the garage at home until needed.

I probably should have made that point clear. THANX tonyk for pointing this out.
 
#21 ·
Point taken here I guess. I'm not doing strip work with the car anyway so I really cant warrant the use of NO2 in the car hooked up or unhooked. I like the sound of NO2 and the benefits it can add for performance at the strip. But never had I been encouraged or been tempted to put on a nitrous bottle in my car in its street state.

But the point was made clear I am aware of that and appreciative that something so important is stated for those that do not know!
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top