Anyone with Procharger experience - come in!

[chief455]

getting my car with an F1 - 10psi and 8.5:1

should I be looking at a bypass valve and water/meth injection for 93 octane street driving?

[Grr]

with that compression 10psi is nothing, over 15 you would be looking for meth, assuming your intercooled. Also get the biggest bypass you can, or get 2 tial 50mm BOVs. I have a vortech Mondo bypass and am going to add a second small regular BOV just for high rpm security. you can never have too much bypass on a big blower. BTW i run about 15psi on 93 octane and 9:1

[Fastbird]

Ditto. Pulley that thing and make some serious power. Then you've got a reason for meth and a bigger bypass valve.

[Fire67]

Everyone above is 100% correct. But no one pointed out that the 'stock' procharger bypass valve is junk. At least get one that actually seals. In which case you may as well get the Procharger Race bypass so that you have room to grow.

My D1 made 15psi with the 'stock' bypass valve on this 383 and kept shredding 12-rib belts. I just installed a Race bypass and saw 2 more psi and so far the belt is holding up.

[Fastbird]

Actually, that Procharger race bypass valve is the same thing as a lot of the larger BOV's. You could get a 56mm JGS for about 2/3 the cost and it's almost hte same thing (have one sitting here for my turbo build). IF you're going to get a big bypass, look at the larger BOV's too.

[chief455]

Actually, that Procharger race bypass valve is the same thing as a lot of the larger BOV's. You could get a 56mm JGS for about 2/3 the cost and it's almost hte same thing (have one sitting here for my turbo build). IF you're going to get a big bypass, look at the larger BOV's too.
thanks for the replies!
what is a BOV?

pROCHARGER HAS THE $155 INLINE DEAL OR $55 SEALED DEAL
WHAT IS THE REAL RISK IN A LOWER COST BYPASS?
pLEASE EXPLAIN WHAT THE BYPASS DOES IN NORMAL OPERATION THAT MAKES IT NEEDED..sorry - caps lock is where my enter key used to be
Also - where does the valve install?

the car was tuned by thunder raciing
will i need more incector/tune if i go to 15psi?

[Fire67]

Actually, that Procharger race bypass valve is the same thing as a lot of the larger BOV's. You could get a 56mm JGS for about 2/3 the cost and it's almost hte same thing (have one sitting here for my turbo build). IF you're going to get a big bypass, look at the larger BOV's too.

Physically they look and almost operate the same. With the exception being that BOV (designed for turbo's) only open when you let off from some sort of boost level. This may be because a turbo is not moving air at idle and the motor is therefore pulling air through it. An open valve would allow unfiltered air to enter the engine.

A supercharger Bypass valve will stay open at idle to allow all the air the SC is moving to vent, decreasing the amount of idle surge and air heating that occurs.

They are different because a SC is ALWAYS moving air, while a turbo doesnt neccessarily move air while at idle.

Now to answer your question, your going to need a larger (think $360-450) Procharger RACE bypass valve or equivalent to vent all the air that an F1 is moving. Especially when you go WOT to redline then let out of the throttle. In such situations, the throttle closes, blocking the airflow. So it reverts and sends a wave of pressure back at the blower. This can damage the head unit itself, along with intercooler end tanks. The purpose of a bypass valve is to allow this wave to vent before it causes damage.

The reason I mentioned the sealing idea is because the inline one from procharger will bleed off a few pounds of boost because it does not seal. It is also too small to vent off the amount of air that an F1 moves.

[chief455]

Fire67 - thanks
so the procharger race bypass opens instantly when the throttle is lifted? under all situations? how does it get the trigger to open/close the bypass?postion, vacuum, computer?
I'm learning...

[Fastbird]

Physically they look and almost operate the same. With the exception being that BOV (designed for turbo's) only open when you let off from some sort of boost level. This may be because a turbo is not moving air at idle and the motor is therefore pulling air through it. An open valve would allow unfiltered air to enter the engine.

A supercharger Bypass valve will stay open at idle to allow all the air the SC is moving to vent, decreasing the amount of idle surge and air heating that occurs.

They are different because a SC is ALWAYS moving air, while a turbo doesnt neccessarily move air while at idle.


I have to disagree with everything here. They're vacuum operated valves and open dependent on vacuum. Turbo's move air at idle just like a supercharger, just not in the same manner. I can factually say that my BOV on my Celica (different car, same concept) vents at idle because it's seeing enough vacuum to open the valve. Can't hear my vette's because they're recirculated, but they're probably doing the same. Having held both an ATI Race bypass valve and a JGS 56MM BOV in my hands, I saw almost no difference to make me think they operated differently.

Want proof? Take a look at England Green's latest build on the Corvette Forum. A 402 LS2 based motor with a Procharget, and he's running a Tial 50mm BOV just in front of the TB as his only means of venting.

Just my limited knowledge $.02.

[Ponyhntr]

I have to disagree with everything here. They're vacuum operated valves and open dependent on vacuum. Turbo's move air at idle just like a supercharger, just not in the same manner. I can factually say that my BOV on my Celica (different car, same concept) vents at idle because it's seeing enough vacuum to open the valve. Can't hear my vette's because they're recirculated, but they're probably doing the same. Having held both an ATI Race bypass valve and a JGS 56MM BOV in my hands, I saw almost no difference to make me think they operated differently.

Want proof? Take a look at England Green's latest build on the Corvette Forum. A 402 LS2 based motor with a Procharget, and he's running a Tial 50mm BOV just in front of the TB as his only means of venting.

Just my limited knowledge $.02.

I'm going to have to side with Fire67 on this one. ;) He's EXACTLY right. ;)

[Fastbird]

Ok then, someone explain to me how they operate differently then. I've seen BOV's used instead of the race bypass valves many times with no ill effect. What internally is different and how is this affecting the operation and it's effect on the air being moved? I'm looking to learn something here.

[Ponyhntr]

Ok then, someone explain to me how they operate differently then. I've seen BOV's used instead of the race bypass valves many times with no ill effect. What internally is different and how is this affecting the operation and it's effect on the air being moved? I'm looking to learn something here.

Blow off Valves typically have springs in them rated for a certain PSI. Because of this, vaccum cannot pull the valve open. It will only open when pressure in the tubing exceeds the PSI rating on the spring.

Yes, people do run BOV's instead of surge/bypass valves on supercharged applications, but they should be advised not to. Because of the excess air moving, it can cause tuning (driveability) issues (expecially with mass air cars), can cause compressor surge, and also belt problems.

It's best to stay away from them for supercharged apps. :)

[Fastbird]

Blow off Valves typically have springs in them rated for a certain PSI. Because of this, vaccum cannot pull the valve open. It will only open when pressure in the tubing exceeds the PSI rating on the spring.

Now, correct me if I'm wrong here, but a lot of those aftermarket blow off valves have adjustments where you can change out the springs and also use a set screw to adjust the tension on the springs, allowing fine tuning of the blow off valve. Would this not allow it to act just like a bypass valve when properly set (I.E. to bleed air at x amount of vacuum and under).

[Ponyhntr]

Now, correct me if I'm wrong here, but a lot of those aftermarket blow off valves have adjustments where you can change out the springs and also use a set screw to adjust the tension on the springs, allowing fine tuning of the blow off valve. Would this not allow it to act just like a bypass valve when properly set (I.E. to bleed air at x amount of vacuum and under).

No, it wouldn't. The spring is actually holding the piston shut on a BOV. It's a much heavier spring than what is in a bypass valve. This is why vacuum cannot pull it open. I've read where a BOV company was offering -x psi springs to turn the BOV into a by-pass valve, but I have not heard of anyone using them with any success.

[Grr]

They can be adjusted to work properly very easily. I only plan to use as a secondary valve though. For one, most are reasonably loud. I plan on using it to supplement my vortech bypass and keep it fairly tight. This way it will be availible upon really high loads when i dont think the vortech is sufficient.
Overall i prefer the Tial 50mm BOVs because of their low price and high quality. Also they can be had with a very light spring, i think as low as 2psi. Even an engine with a HUGE cam should pull enough vacuum to open that, that is overall a very small pressure differential.

[Fastbird]

Riddle me this then? Why does my HKS SSQV BOV on my Celica, the Bosch BOV's on my Corvette, and the JGS 56mm BOV for my T/A all have vacuum ports on them if they simply operate off of the valve being overpressured by the incoming air?

[Fire67]

That is where your miss understanding... If you ever watch a vacuum gauge while doing a pull, you'll see that at the very moment the throttle is closed, the amount of vacuum will very easily exceed what the motor makes at idle. Therefore it is enough to pull the valve open. But at idle, the valve will stay closed.

It's not the pressure inside the tube opening the valve at all.

Theoretically, you could change out the spring + back off the tension of the adjuster to solve this. But I have not seen a spring that will physically fit be loose enough. We tried this with a buddy's turbo car and could not get the valve to open at idle.

On the opposite end of the spectrum, it is very easy to make a SC bypass valve stay closed at idle by simply tightening the adjustement screw.

So Fastbird, you can make a tubo BOV work, if you can find a light enough spring that not only fits, but will hold the valve shut under boost. But why bother, just buy a bypass with the correct spring pressure from the get go.

[chief455]

ok - bypass valve, good one that won't leak.
where do they install? what do the hook to - manifold vacuum and air before the throttle body?
anyone have an installed pic?

60lb injectors will handle how much boost?
With a slightly rich tune and 10psi now - at what boost will I need to re-tune timing etc in the PCM?

water/meth - at what compression/boost on 93 octane is this mandatory or just better safe than sorry?

thanks guys!

[Fastbird]

That is where your miss understanding... If you ever watch a vacuum gauge while doing a pull, you'll see that at the very moment the throttle is closed, the amount of vacuum will very easily exceed what the motor makes at idle. Therefore it is enough to pull the valve open. But at idle, the valve will stay closed.

It's not the pressure inside the tube opening the valve at all.

Theoretically, you could change out the spring + back off the tension of the adjuster to solve this. But I have not seen a spring that will physically fit be loose enough. We tried this with a buddy's turbo car and could not get the valve to open at idle.

On the opposite end of the spectrum, it is very easy to make a SC bypass valve stay closed at idle by simply tightening the adjustement screw.

So Fastbird, you can make a tubo BOV work, if you can find a light enough spring that not only fits, but will hold the valve shut under boost. But why bother, just buy a bypass with the correct spring pressure from the get go.

Ok, I see what you're saying. I'm hung up on the physical operation which is essentially the same, but the forces affecting the operation that are different is what I was misunderstanding. Thanks for helping clear that up for me guys!

[Ponyhntr]

ok - bypass valve, good one that won't leak.
where do they install? what do the hook to - manifold vacuum and air before the throttle body?
anyone have an installed pic?

60lb injectors will handle how much boost?
With a slightly rich tune and 10psi now - at what boost will I need to re-tune timing etc in the PCM?

water/meth - at what compression/boost on 93 octane is this mandatory or just better safe than sorry?

thanks guys!

Here is mine:

http://i33.photobucket.com/albums/d92/ponyhntr/LT4383/062907002.jpg
http://i33.photobucket.com/albums/d92/ponyhntr/LT4383/062907001.jpg


The vacuum line that goes to the valve needs to be manifold vacuum, and you should put the valve between the blower and the intercooler. I'm not running an intercooler, so it is before the MAF.

60lb injectors are usually good to about 750 rwhp through a 6-speed, but there are many other variables that can vary that number.

Anytime you change boost its recommended to have the tune updated/checked.

[Fire67]

Just something that needs to be pointed out.

Pnyhntr stated to but the valve before the MAF... This is typically true for MAF equipped vehicles because you do not want to vent measured air. The pcm does not like it when we do things like that. However, some people do not like the sound of the valve and try to quiet things down by recirculating the bypassed air back into the intake of the blower... In this case, you can put the MAF on the inlet side, before the air gets plumbed back in (so the air doesnt get measured twice), or on the pressure side after the bypass valve (just like you would if venting the air to atmosphere like Pnyhntrs setup.

Pnyhntr has the same bypass valve as me, and it's a very high quality piece. Exotic Performance Plus sells them for $360

With the F1 procharger, your capable of easily eclipsing the capabilities of those 60# injectors.

For sizing injectors, the idea is to figure for a good estimate of flywheel HP then oversize the injectors a little so you have room to grow.

Here's a handy formula for injector sizing:

Flywheel HP X BSFC / #of cylinders = Lbs per hr @ 100% duty cycle

For a safe duty cycle of 80%, divide the result of the above equation by .8

BSFC = Brake Specific Fuel Consumption, a good estimate for this on a SC'd motor is .55-.6 I use .6 as it tends to add a little cushion room.

Example equation for 900 fwhp:
(900 X .6) / 8 = 67.5 lbs per hour @ 100% duty cycle
67.5 / .8 = 84.375 (85 lbs per hour @ 80% duty cycle)

My with my 383 I had to move my base fuel pressure up to 65psi (from 45) to get my duty cycle down to about 80% with 75# injectors. At that pressure, they flow a little over 90lbs per hour. So I swapped them out for a set of 95's.

As for the point that methanol is needed... It's really not ever needed if you don't need max effort out of pump gas. And depends on your current intercoolers ability to keep IAT's in check. With pump gas, the point were you need methanol is determined by the point at which you simply cannot make any more power without getting into problems. Once you get there, add some methanol and crank it up! The methanol will cool the IAT's, add octane to the fuel mixture, and allow you to run more timing. The cooler IAT's and increased timing is where you find additional power from methanol.

[chief455]

pnyhntr, fire67 - your details are appreciated and understood.
I hear above 60# injectors are mostly sold for a different impedence - does this require modification to my eletrical plugs at the injectors?
As I plan to increase my car from 10 to 15psi, I'll add the bypass valve as explained, determine injector size and ensure fuel supply is up to the job, and get the car tuned.
Once the car arrives this week I'l know better exactly what hardware is installed and how.
thanks for the TECH help ! I like this site best already ;)

[Fire67]

As far as going to low inpedance injectors - you just need an injector driver box like an Acceleronics Versa-fueler or AEM injector driver. All these boxes do is take in the output from the factory pcm, convert it to a peak and hold type signal and isolate the stock drivers in the pcm from the draw of the new injectors. They do require quite a bit of wiring to install though. As you will have to locate the injector wires in the harness, and then cut-splice the driver box in.

As far as fuel supply goes... The equations I already provided can help with that... Use the injector size calculation at 100% duty cycle, then multiply by 8 to get total required volume... Then just make sure the pump you have or plan to get can supply that volume at full fuel pressure. With a 1:1 regulator installed and recieving manifold vacuum/boost, you will have Base Fuel pressure (45psi) + boost pressure (15psi) = 60psi total.
Now even though injectors flow more fuel at higher pressures, this is not the case with a 1:1 regulator. Simply because the proportionate increase in fuel pressure is used to keep flow the same when you have pressure in the manifold trying to keep the fuel from coming out.

[Fire67]

Hey Fastbird: on a side note... I did some maintenance on a '03 Henessey Venom Viper today. It had twin tial style 50mm BOV's with the twin turbo's. They wer not opening at idle.

So I messed around with them a little bit and managed to get them to hold open at idle ever so slightly... Just enough opening to hear some air hissing out.

So I got ever more curious and took one off and disasembled it. And disasembled my ATI race valve right next to it. Wish I had a camera with me because they are almost identical. The spring pressure was even very close to the same (feeling by hand). The main difference was the size of the diaphram (sp?). The ATI diaphram was quite a bit larger in diameter. Which means that any vacuum it sees has more surface area to pull on. Which would over come the spring pressure easier and enable it to hold the valve open at idle with very little vacuum.

So I reasembled both, and used a mighty vac with a gauge to see what kinda vacuum was needed to open the valves. With normal adjustements on both, the Tial style needed almost 18" while the ATI would open at 5". The ATI opened fully at 5" so I loosened the set screw on the tial style and got it open ever so slightly at 11"

Based on my disection, the spring is only there to hold the valve shut... If your boost level manages to push the valve open, you would need to tighten the set screw or get a stiffer spring. The diaphram is what opens the valve, so it's size is directly related to how much vacuum is needed to over come the spring pressure.

[chief455]

thank you for the great info!
UPDATE:
Car arrived
has PISC head unit, twin intercoolors - looks like the stadard 93-97 system.
has a 230/239@ .050 with .530/.546 lift on a 114, installed at 110 intake center line.
Car idles with 10 on the vacuum gauge - raise slightly with rpm.
has 60lb injectors, Crane 600 ignition, Pacesetter longtubes with duals and was Thunder tuned.
Can I still raise boost as outlined in the previous posts?
Or am I at about a safe setting?
I have not determined the heads - but just mild porting and told forged internals. I do have the JE reverse dome piston receipt and bill for shop labor in line with a hot rebuild cost.

[Fire67]

Sounds like you should enjoy it as is... That's a fairly small head unit. If you aren't satisfied with the current power level, you really need to determine whether or not you can safely spin that little head unit any faster.

I'm not sure of a P1SC head unit's max impeller speed... But it is readily available on the Procharger's website.

Equation for impeller speed: CP/BPxEngine RPMx step up ratio=impeller speed
CP= Crank pulley diameter
BP= Blower pulley diameter
Engine RPM= rev limiter setting (max safe RPM for engine)
Step up ratio= Internal step up ratio of blower (D1sc is 4.10)

Figure that out and you will be able to determine whether you can or cannot spin your head unit any faster to raise the boost level.

[chief455]

thanks
max is 62,000 rpm and the F1 is 70,000.
I'll be awhile to measure pulleys and probably just drive as is - it's not slow ;)
how are you getting 15psi out of yours?

[Fire67]

It's pulleyed to max the blower out at 6500 engine rpm... 15psi is all that it would make with the twin highflow intercoolers and leaky stock Procharger bypass valve (the tube thing). I have a Reichard Ultra Grip blower pulley (3.25") and the stock procharger (7.625") crank pulley.

I have not yet tested it with the Procharger race bypass because I have not been able to bring the motor up that high in rpm's yet... Still working at the tune.

I have however been strongly considering eliminating the intercoolers all together and running Sunoco Maximal 116 race gas and using the methanol to cool the charge temps down...

I would have to change pulleys though and start off with a lower boost level to make sure I don't grenade something. It would be on the ragged edge of safety for the motor, probably closer to the melt some shit down side of that 'fine line'.

[Fastbird]

Hey Fastbird: on a side note... I did some maintenance on a '03 Henessey Venom Viper today. It had twin tial style 50mm BOV's with the twin turbo's. They wer not opening at idle.

So I messed around with them a little bit and managed to get them to hold open at idle ever so slightly... Just enough opening to hear some air hissing out.

So I got ever more curious and took one off and disasembled it. And disasembled my ATI race valve right next to it. Wish I had a camera with me because they are almost identical. The spring pressure was even very close to the same (feeling by hand). The main difference was the size of the diaphram (sp?). The ATI diaphram was quite a bit larger in diameter. Which means that any vacuum it sees has more surface area to pull on. Which would over come the spring pressure easier and enable it to hold the valve open at idle with very little vacuum.

So I reasembled both, and used a mighty vac with a gauge to see what kinda vacuum was needed to open the valves. With normal adjustements on both, the Tial style needed almost 18" while the ATI would open at 5". The ATI opened fully at 5" so I loosened the set screw on the tial style and got it open ever so slightly at 11"

Based on my disection, the spring is only there to hold the valve shut... If your boost level manages to push the valve open, you would need to tighten the set screw or get a stiffer spring. The diaphram is what opens the valve, so it's size is directly related to how much vacuum is needed to over come the spring pressure.


Hmmmm.....interesting. So would this mean that with a spring change the BOV's would work just fine in place of the more expensive "blower specific" bypass valves??? Either way, thanks for taking the time to break those down and look at their innards and reporting back like that. Cool thing to find out.

[Fire67]

Hmmmm.....interesting. So would this mean that with a spring change the BOV's would work just fine in place of the more expensive "blower specific" bypass valves??? Either way, thanks for taking the time to break those down and look at their innards and reporting back like that. Cool thing to find out.

The only thing I could see possibly go wrong with that is the the spring is gonna have to have a tension that is higher than your boost number X the surface area of the valve that holds the air back. Probably could be done, but it would be a fine balancing act.

[chief455]

It would be on the ragged edge of safety for the motor, probably closer to the melt some shit down side of that 'fine line'.
sounds like a good idea to NOT do.
thanks for all your input - very educational.
How do I go about determining what pullys I have?
measure the outside dia or look for numbers on them?
6200 would be my max rpm, and it's tuned for that.
I want to be sure I have all the spin I can for boost.
I believe I have the stock bypass too - need to follow the tubing highway on the car when I get a break from work..

[Ponyhntr]

sounds like a good idea to NOT do.
thanks for all your input - very educational.
How do I go about determining what pullys I have?
measure the outside dia or look for numbers on them?
6200 would be my max rpm, and it's tuned for that.
I want to be sure I have all the spin I can for boost.
I believe I have the stock bypass too - need to follow the tubing highway on the car when I get a break from work..

The crank pulley would be 7.65". There should be a number stamped on the face of the blower pulley, which is the size. If there is no number,you would need to measure the diameter WHERE THE BELT RIDES, not across the shoulders.

[Fire67]

The Lt1 kits either came with the 7.65 or an 8 somethin inch crank pulley....

[Ponyhntr]

The Lt1 kits either came with the 7.65 or an 8 somethin inch crank pulley....

Not really. They all come standard with the 7.65". The 8.5" inch is available, but is usually not needed, even when maxing out a P/D-series. They can come in handy with the F-series though. ;)

[Fire67]

I wish I had an 8.5" crank pulley. Then I could have used a larger diameter blower pulley to max the blower out. Which would have afforded more belt contact area on the pulleys and resulted in less slip.

[Twisted Z]

Man an F1 seems like ALOT for only 10Psi.

BTW boy I would listen to Josh. He MAY know a thing or two about ProChargers :devil:

He knows enough He is researching a setup for us :devil: