tjwong

I was tuning a C5 today on my chassis dyno and all of a sudden it just cut out, came back and cut out. I had just installed a Magnuson Magna-volt fuel pump booster, so I had thought something was goofy there. But that wasn't the case here is what I found:





The MAF sensor screen blew off and into the sensor elements causing the sensor to go to zero which basically was a fuel cut! So if you are dyno tuning or just out for a WOT blast and she cuts off, check out your MAF, it will also set a code for low MAF Freq.

cobill1972

Good info to share.
Is that a 250 or 500 dyn I see in the background?

Thanks,
Bill

Corvette-Chris

Last year sometime my MAF screen had blown off causing my tuner all kinds of problems.

I believe it was due to a nitrous backfire caused by some tuning done by the previous tuner before I went to DP. Mine was nearly blown completely in half.

tjwong

Hi Bill my dyno is a MD600HP with dual eddy current power absorbers. Its been a great tuning tool with over 8k miles of tuning on the roller! I am thinking about a new dyno, one called a HUB Dyno, it is like the Autodyne but its the European version made in Sweden several OEMs uses them and they are accurate to within 1%. They say if you go to three different Hub Dyno centers that are equipped with their dynos the readings would be within 1% of the original test center. Its a pretty cool unit in that the car powers up a hydraulic pump which with pretty cool measurement devices, it will measure power and torque, also what is cool is that the same power from the car will power the cooling fan via its hydrualic pump and motor, it creates wind speeds upwards of 100 MPH

Here is a link:

http://www.rototest.com/index.php?DN=1&Visitor=4

cobill1972

======================================== =====
That's pretty cool the only thing that steered me away from Autodyne is that i have heard sometimes it can be a pain fitting up the hub to dyne. Let me know if you end up going with that. I recently went to a training class at the Mustang Dyno facility where I checked out the place and saw some of the new gadgets. I purchased my Dyne about 6 moths ago. I have the HD unit with the 24k axle weight for some of the Diesels we tune on. Two things other than the power curve test that sold me on Mustang was the 1/4 sprint and the loaded test like simulating loads on diesels, and simulating a load up a grade. The load simulation has been a huge help on driveability issues we get time to time.

Bill

tjwong

Hi Bill, that also was a good selling point for mr as well. Do you have the 750HD model? If you do mine us the 200 mph model of the 750HD Dyno . Mustang upgraded all my controls to the new Powerdyne hardware and software, then I added wireless control to it as well, so I can operate the Dyno via my laptop sitting in the car. The hub dyne is pretty expensive especially when mine is 100% paid for at this time.

Have you used the quarter mile sprint test ? If so how did you like it? I have tried it a few times, it seems to be accurate within a tenth or two and more so with lower powered cars that don't haze the tires as much.

minitech

So were you able to tune so the idle settles down every time without the screen?

minitech

It doesn't look like a stock screen, holes too large. There is a new MAF now aftermarket with larger honeycomb like that. Was it a commercial aftermarket or was it a home made one? Would like to know if the large hole aftermarket can stand up to boost.

tjwong

Yep not a problem. Stock Z06 MAF sensors came without a screen from Delphi.

It was definitely a Delphi MAF, however it appears that some aftermarket company modified it with their own screen, and likely didn't secure it properly. Obviously this one with larger holes didn't stand up well to boost at all. The better way to do it would be to install a late LS7/LS3 style MAF sensor into the system using a custom made tube, which is easily done. Then you don't have to worry about screens at all.

cobill1972

---------------------------------------------------------------------------
I have MD250hd, but I'm thinking about goint up to the 500awd on trade in already. I love the sprint times and the powerdyne software. Usually what I do is if the car has a tune in it already i'll make a base power curve test and if everything looks ok on the tune we will do a base 1/4 sprint test. I have the optional center axle pull down to cut down on the burning the tires down plus it helps if they have a drag radial of some sort. Anyway I do a before and after for the customer so it helps eliminate the famous question "what will it run". We actually tuned one customers car and gave him the 1/4 results he then missed his time trials so he dialed in off of the dyno results. He made it to runner up before he fell asleep at the light and lost in the finals.

tjwong

Cool! I have the center pull down option as well. However its tough to use on some cars. So it doesn't get used much. So far I have found with the new hardware and software I am able to hold much higher powered cars on this dyne without blowing the tires off. The earlier MD7000 series software had some issues controlling the loading of the PAUs during a power sweep. I like the Roto-Test dyne as it seems more robust with much more advanced controls. All of which is made to industrial specifications. Mustang uses a standard desktop PC and gives you a roll around cabinet to place it in. Roto-Test supplies an industrial PC cased in an industrial rack mounted cabinent, its I/O rack is also made up of an industrial based PLC controller to handle sensor input and control devices. All this also adds to the cost as the Roto-Test is 65k for their base 1000hp system.

zeevette

This' my car that Tom's talking about. The screen is an aftermarket Halltech that IMO worked great when I was NA. I threw alot of lean codes w/o any screen (stock) and they were rare after I installed the screen. I believe it works as advertised, but then, my car is supercharged now, so the pressure is increased by a large margin. BTW, Thanks, Tom, for the great work, and attention to detail. It is greatly appreciated. It's been raining since the tune (Sat.) and the traction is non-existent, but driving it home, and a little around town, I got 26 MPG. Not too bad on a 600+HP car.

tomiboy

Tom,

Would that honeycomb screen fit in front of a C6 MAF? I get surging ever since installing an Airaid and thought this might help. 2 tuners have not been able to tune it out. Otherwise I'm going back to stock intake.

Milan

Tomiboy try moving your MAF closer to the throttle body

ysb02

That looks a lot like the screen Halltech is making for their CAI setups.

Z06supercharged

That honeycomb stack was being made by someone over on the HPTuners forum earlier this year. He was asking for testers and sending it to them freebie just to try it out. I was on the list to get some and try it but thought about and decided not to as I didnt think it would stay put.

madmatt9471

WOW! at first I thought you found a bowl in the MAF

Kidding! Good find, at least it didn't destroy the MAFwires too

Thanks,matt