Charles.rogers1

So A really dumb question I feel but whatever better to know than not Have a charged 96, automatic, with no blowoff valve. because it doesnt release boost like manual cars right.. lets say I installed one would it work? Like if when I stopped gas fully would it release and make noise?

Thank you,
Charles

mnstrlt1

On your 96', the blow off valve is plumped back into the intake track (due to the MAF sensor) so you won't get that "blow off" sound you might be thinking of.

Provide more details about your setup. I am not aware of any vendor who offers a supercharger without a blow-off/bypass valve.

Charles.rogers1

Smaller of the prochargers, PS-1C I believe it is? Maybe it is somewhere that I am not seeing or something that does not look like a traditional bv..?

383tpimachine

You do not have to have a BOV plumbed back in. Most of the procharger BIG RED RACE VALVE (loud and awesome) are vented to the air. bleeds excess pressure and you should have one.

Charles.rogers1

Alright well it is all coming out atm so I will look again if there isnt one could one be installed or is what mnstrlt1 said that it will not be the same sound as a turbo release?

armysnipe

If you haven't removed your parts yet you can accelerate in first gear getting the RPM's up and then let off the gas. You should here a BOV sound if one is installed. It shouldn't matter if it's recirculated or not you'll still be able to hear it. If you don't have one installed, I'd definitely get one. Depending on your boost levels will depend on what type to install. I've switched from an auto to manual and the BOV is much more noticeable on the manual. Post some pics of what you have so we can make a recommendation. I went from the small Bosch valve on a P-1SC recirculated to a D-1SC with an enclosed procharger big red race valve vented to atmosphere and love it. Since I have an inter cooler I had to get creative. So I had it welded to the inter cooler. Tucked under the shroud it's not too loud, although it sounds like a jet landing.

mnstrlt1

He has a MAF dude, the sensor (mounted in front of the blower intake) measures the air before it gets to the engine; therefore, the bypass valve/BOV (in this particular scenario) has to recirculate the air back into the intake track. This is now mine is too (96').

My 93' (speed density) had a BOV to atmos.

mnstrlt1

I'm running 12psi in my vortech V1 T-trim and I can't hear a thing. I'm running a larger vortech BOV. The same BOV was very audible on my 93'.

Keep in mind, he has a 96' OBD-II.

383tpimachine

Also matters where you are mounting the BOV. If before the maf it will not need to be recirculated

HighMileage

On my 96 procharger setup there is a bov vonnected to the intercooler inlt pipe and the sent to a t pipe via a 1.5 inch hose.

The T pipe is right after the MAF, which is in the front passenger side wheel well next to the coolant overflow tank.

Look for the 1.5 inch hose after the MAF and follow it back to the BOV.

HighMileage

And yes its plumbed after the MAF such that the computer sees the proper airflow.

As explained if you vent to outside after MAF has measured g/s airflow our fuel mix will be off when the valve opens.

For MAF car you would need to relocate maf after intercooler before throttle body and have Bov before intercooler.

In any case if your install was done right you have a bov already.

mnstrlt1

Agreed. The MAF would have to be BETWEEN the compressed air and the TB to then place the BOV in front of the MAF and TB.

Trying not to complicate it for the OP. more than likely, this is a "traditional" procharger setup (no alteration to the location of the MAF).

383tpimachine

I understand. Was just trying to get him the loudest noise possible out of the BOV.

Charles.rogers1

Alright I will get out there and do more looking for it and see what I can come up with

Thanks a lot guys,
Charles

lcvette

mine makes BOV noises because it has a BOV. you have a bypass valve. if you want to vent to atmosphere, you need to relocate the MAF between your throttle body and intercooler. then you can add a atmosphere vented bypass valve and get the desired whoosh you are looking for. I find the MAF works great located on the pressure side on later lt1 cars!

Chris

BlowerWorks

Hi All ! First IC is 150% correct on MAF location - discharge side of blower better - always !!!!!!!!! The reason is centrifugal pumps (Vortech - ProCharger - etc.) are very sensitive to any kind of inlet restriction. Centrifugal pumps love to push not suck. Hence, if possible, locate the MAF on the outlet.

Next - definitions. Maybe mine but a BOV is used to relieve excess pressure/boost on the way up, not on the way down. A by-pass or surge valve is relieving pressure on the way down, hence it is vacuum actuated not boost activated. Some valves can do either. The bigger the valve the more you hear. The 'surge valve' is designed to relieve the pressure oscillations when you let off of the throttle and makes life easier on the supercharger bearings and or seal(s).

Next, as all of you above note, if the vehicle uses a MAF, and if the MAF is located prior to the surge valve then the surge valve must be plumbed such that the excess air is re-circulated. Otherwise on decel you could be adding a ton of fuel as measured by the improperly plumbed MAF/surge valve.

On the 1994 thru 1996 Vette you can switch your tune to S/D (it's already built into your PCM in case of a MAF sensor failure) with a click on the box in the tune. I much prefer the MAF tune. If interested to experiment simply unplug your MAF and the PCM will switch to S/D. Drive it and see. A code will set but no mind it. Clear code by dis-connecting battery.
BR - greg

BlowerWorks

AND - forgot to say that another reason for the surge valve on the MAF engine is w/o it the engine will 'hunt' like crazy as the air flow goes back and forth over the MAF sensor. Many LTx cars with the MAF in the headlamp cavity had this problem because the MAF saw the air flow fluctuations. The solution was either a bigger surge valve and/or relocation of some air inlet components.

MrBigDee

Hi,
I´m installing Procharger P600B unit to my automatic 85 Corvette. I have now L98 TPI MAF engine, better cam, headers, 113 alu heads, 1.6 rockers, SLP porterd runners and plenium, 34lb EV14 injectors, 2,5" exhaust....dyno tested now 324hp.

Also I will install Aquamist HFS3 methanol / water injection system. I am planning to use 50/50% water and alcohol.
I have also all electrical gauges which needed. (fuel, boost and AFR wideband)

Next, I need help to choose right valve to my supercharger.

Is the Procharger red race valve right one?
Or the Procharger surge valve?

Thanks,

KSA Aaron

The L-98 Procharger P-600B kit for the early C4s comes with the correct Blow OFF Valve. Use the blue hat BOV supplied with the kit and vent to atmosphere as the directions detail.


Why change something that is not broken...

MrBigDee

Hi

Sorry, my mistake. I do not have a whole kit. Only P600B head unit and bracket. The rest of the procucts I need to buy separately.

Also I need to find good and right FMU?? Or should I go original FMU?