Help with S/C noise on ACE kit!

Originally Posted by TopgunZ

There's a muffler you can put on the QRJ and it will be gone. Redondoaveb has already done this. I have made a different version. They are free to anyone who bought an ACE kit.

Originally Posted by bcfromfl

Sorry to hear about your sad experience!

I admit I don't know a lot about all this, but from what I understand, it sounds like the PT50 has too strong of a spring in it (for starters), and doesn't open under light load or at cruising speed...forcing the extra air out the compressor side.

Originally Posted by redondoaveb

I've tried Vortech's Maxflow Mondo bov which is adjustable and it did the same thing no matter what tension was on the diaphram. With the Tial bov's I've tried a 1.5, 2, 3, 4 and 6 psi springs in them. They all did the same thing.

Originally Posted by bcfromfl

This, I think, is more evidence that it's not all on the BOV side. You can perhaps moderate the sound, change the pitch, or RPM range, but the rest of it is coming out the compressor.

Originally Posted by bcfromfl

Hi everyone –

I finally was able to get a pro speed shop to install the ACE kit and fuel upgrades, with the work completed last weekend. We ran into a major noise issue with the PT50 BOV that was sent with the kit. It squeaked and chattered even at idle, and the shop owner said that it sounded like Tweety Bird. He wasn’t happy with it, and knew I wouldn’t be, so he opened up his race car and pulled out his Tial Q50 to install instead. There wasn’t enough clearance for the Q50 between the intercooler and a/c compressor, so he moved the intercooler ¼” with spacers. That got rid of the high-pitched squealing at idle, and moved the “chatter” from the supercharger into a higher RPM. Now, it does it at cruising speed, 2500-3000 RPMs, when there is no load on the engine. Just a constant chattering, from the driver’s side of the engine compartment. It's quite loud, and simply intolerable!

It’s the shop owner’s belief that it occurs because the supercharger is creating more pressure than the engine requires when cruising, and the pressure is cavitating out the compressor fan blades out the opening of the intake. He’s calling it a type of “compressor surge.” I’ve got the “hair net” filter on over the opening, and he said that if you could rig up a GoPro camera to look at the filter, you’d see it vibrating in and out when cruising. He feels that the solution would be to put a pancake H&N-type filter on the intake, so that the supercharger is always pulling against a slight vacuum. Or, if there might be an S-curved charge pipe that could fit a larger filter behind the bumper. Just something to create a small amount of vacuum on the intake.

I asked TopGunz about this, and he said that the solution is on the BOV side. He said to put the Tial QRJ on, with the Vibrant crankcase filter, and that will fix the problem. Unfortunately, the QRJ won’t fit in the space available, unless there might be a fitting available to turn it at a 90-degree angle…but then you’re messing with the free-flow operation of the valve. (Another option might be to have a 90-degree pipe and mount the QRJ remotely somewhere.) The shop owner is unconvinced that any modification to the BOV will fix the problem. He has installed dozens of s/c kits on Mustangs, and he said every one of those kits has a charge pipe with a pleated filter on it, and he’s never had an issue with this noise.

There are apparently different configurations available for some Tial BOVs, but none for the Q50. There simply isn't a way to connect any kind of pipe to it, to run to a crankcase filter...even if that would fix the problem.

What are the rest of you doing? Any suggestions? Thanks!

Originally Posted by redondoaveb

Does it sound like this?

https://youtu.be/71iNsASAbBE

Originally Posted by TopgunZ

The QRJ fits. The shop owner does not know that the QRJ can run both vertically or horizontally. I literally just installed one last night on the Rotrex kit using the same intercooler and brackets.

By installing that and the 1.5" exhaust port you can place a 1.5" filter on there and it will be much quieter. However it will still be there. I do have a fix that should completely muffle it but I am waiting to get the car up and running to prove it out. I could send one to you if you would like but you would be the first to run it.

Originally Posted by TopgunZ

There's a muffler you can put on the QRJ and it will be gone. Redondoaveb has already done this. I have made a different version. They are free to anyone who bought an ACE kit.

Originally Posted by redondoaveb

Unfortunately, mine still did it with the silencer. The video I posted was with the qrj and the silencer.

Originally Posted by redondoaveb

I've tried Vortech's Maxflow Mondo bov which is adjustable and it did the same thing no matter what tension was on the diaphram. With the Tial bov's I've tried a 1.5, 2, 3, 4 and 6 psi springs in them. They all did the same thing.

Originally Posted by bcfromfl

This, I think, is more evidence that it's not all on the BOV side. You can perhaps moderate the sound, change the pitch, or RPM range, but the rest of it is coming out the compressor.

Originally Posted by TopgunZ

A lot of this has to do with performance gains vs sound gains. If you were to put a restrictive filter pipe off the supercharger and plumb it back into that pipe the noise would be gone. However, due to the Vortech design you will take a massive hit on power potential.

I have all the parts coming to eliminate or at least get it close to eliminated (barely audible) for it to not bother you. I guarantee you will be happy with the results. Ill keep you posted.