D1SC Procharger Installed...Quick ?

[nightsun]

What's up fellas. I am new to this site. I just installed a D1SC on my 04 Mach 1. Its running the 4.15 pulley and the big race valve vented. I know how stupid this question is going to sound but I havent been able to find a specific answer (am going to call ATI today). Eitherway, finally got the car running and fixed a few coolant leaks...drove it on the street and immediately noticed it whistles extremely loud. The sound was actually resinating off the houses in my neighborhood. A buddy that lives two blocks away can hear me driving down my street. Every video I have seen with a procharger installed does not sound this way. It sounds perfect at idle but I was surprised that it whines continuously in every gear. I am thinking that perhaps since I am venting the valve to atmosphere that is where the sound is coming from. Hopefully once I bypass it back into the intake it will quiet down some. Does anyone have any input on this? I would greatly appreciate any information. Thanks fellas

Here is a vid of it idling... [ame="http://www.youtube.com/watch?v=Z4iAzLu2HL8"]YouTube- 04 MACH 1 D1SC Procharger Idle[/ame]

 

[01yellercobra]

The whistling is normal. As soon as you get into boost it'll go away. Something I've noticed is that the slower the blower spins, the louder it gets. I was running a 3.4" pulley and then stepped up to a 3.9" and the blower got louder. I think it has to do with the gears loading/unloading. As for the bypass, venting it back into the intake will quiet it down a lot. I wouldn't do that personally though. I figure it's best to let the hot air out instead of recirculating it so it just gets hotter.

 

[nightsun]

Thanks for the response. So your thinking if I bypass the valve that high pitched sound will quiet down some? You can hear that sound when I rev it in the vid...multiply that by 5 and that is what it sounds like while driving. It almost drowns out my magnapacks. ATI wants me to change the oil and check for metal shavings. I wonder if it will quiet down some if I put a filter on the bypass valve.

 

[01yellercobra]

I can't watch the vid since I'm at work. But I know how my blower sounds. The whine from the gears is always there. Venting the bypass back to the intake will only get rid of the air rush sound. Which will quiet things down a little for you. When I was running the stock crank pulley with the 3.9" it was really loud. Now with the overdrive crank pulley and 3.9" pulley, it's a little quieter. I think it all has to do with the speed of the blower. Although mine doesn't drown out my stingers.

 

[nightsun]

Thanks I guess I'll just have to learn to live with it.

 

[nightsun]

Im thinking...(and hopefully someone with more experience with these systems can elaborate) The big race valve that came with my kit is always open. It only closes when on boost. Im thinking perhaps the higher piched sound(s) are coming from the race valve.

 

[sideways03]

Sounds like it's supposed to. Recirculating the bypass back into the intake will quiet down the AIR noise, but won't have much effect on the whistling. That is just the sound a centri unit makes.

I went from a P1 to a D1 and the D1 is definitely a loud headunit. Go listen to an F1 and you will see how loud they can really be.

 

[01yellercobra]

Give it a few days. You'll forget it's there. That's what happened to me. I pulled my blower off for a while and thought something was broken.

 

[nightsun]

Took your advice and searched...sounds almost identical to this one...

[ame="http://www.youtube.com/watch?v=CwmqKkUyOLc&feature=related"]YouTube- F1A Mach 1 Dyno Tune[/ame]

 

[sideways03]

The D1 is loud. An F1 is louder. It's impossible to compare loudness in videos since there are TONS of variables that change between them. I'm not gonna say there is nothing wrong with your blower, because I have not seen it in person. But from your video, it sounds healthy to me. The D1 is a loud, I don't know what else to tell you.

 

[SpittingCobra]

Dude prochargers are loud.:bored: Open race bypass's make them louder. Get a louder exhaust! You're building a supercharged v8 hotrod here. Don't be afraid of the noise. People are gonna look at you wherever you drive and they'll lose their mind over why your car sounds like a pissed off jet demon.:fm: Just embrace the sheer badassness. :bowdown:

 

[01yellercobra]

I finally managed to watch the video. That sounds about right for the blower.

 

[nightsun]

Thanks for the responses. I better put down enough power to back it up.

 

[01yellercobra]

How did you get the 4.15" pulley to fit? I thought the Mach's used the same set up as the 01's and there's no room for anything bigger then a 3.9".

Depending on what's done to your motor you should be in the high 400's. Even if you're making 10psi.

 

[nightsun]

The only thing we did was notch the vc as you can see in the vid. Im starting the tuning process tonight. I went with an email tune from Eric Brooks...I am hoping for 430whp max. I dont want to push the stock block to the limit.

 

[01yellercobra]

Ahhh, ok. I missed that. I didn't want to notch my valve cover. With your compression you might be over 430 without even trying.

 

[97desertCobra]

Dude prochargers are loud.:bored: Open race bypass's make them louder. Get a louder exhaust! You're building a supercharged v8 hotrod here. Don't be afraid of the noise. People are gonna look at you wherever you drive and they'll lose their mind over why your car sounds like a pissed off jet demon.:fm: Just embrace the sheer badassness. :bowdown:

+1. I have a D1SC OP and my blower is about as loud as yours is but yours seems to be a little louder. Difference is I'm not running the race bypass valve. You will get used to it or you will hate it. I for one LOVE the sound and I'm looking forward to it getting louder when I switch to the race bypass valve. The sound is very intimidating to other cars and the bypass flutter scares off the ricers. To people that are unfamiliar with cars or centri blowers for that matter ask whats wrong with my car. I usually say its a vaccum leak ;-)

 

[IUP99snake]

How did you get the 4.15" pulley to fit? I thought the Mach's used the same set up as the 01's and there's no room for anything bigger then a 3.9".

Depending on what's done to your motor you should be in the high 400's. Even if you're making 10psi.

If you're looking to bring down the boost a bit with the D1, there's another option instead of a bigger blower pulley and having to clearance the valve cover: Just get an underdrive crank pulley. That'll have the added benefit of less parasitic losses from the million other accessories on the front of the motor.

But about the noise. You're right, it's loud!! And sinister. It does seem to get louder around idle. The howling noise the procharger makes has little to do with the air flowing through it. The billet gears that procharger uses in their blowers is what makes most of the noise. Those billet gears have a resonating point around idle which causes the gears to "sing". Thats why the howling noise tends to lessen if you get a smaller pulley (changing the idle RPM of the blower), or as the RPM's increase.

If anyone asks you if its got a blower, just tell them it's got a bad power steering pump.

Homer

 

[Cobra96SVT]

M p-1sc whistles loud as a mofo, I always pull up to my house and if my dads in the back yard behind the house he says he always knows its me from the whistling.

 

[01yellercobra]

If you're looking to bring down the boost a bit with the D1, there's another option instead of a bigger blower pulley and having to clearance the valve cover: Just get an underdrive crank pulley. That'll have the added benefit of less parasitic losses from the million other accessories on the front of the motor.

But about the noise. You're right, it's loud!! And sinister. It does seem to get louder around idle. The howling noise the procharger makes has little to do with the air flowing through it. The billet gears that procharger uses in their blowers is what makes most of the noise. Those billet gears have a resonating point around idle which causes the gears to "sing". Thats why the howling noise tends to lessen if you get a smaller pulley (changing the idle RPM of the blower), or as the RPM's increase.

If anyone asks you if its got a blower, just tell them it's got a bad power steering pump.

Homer

I'm trying to keep the bigger pullies on there. That's why I'm running the overdrive crank pulley. I want to get all the belt wrap possible.