Restrictor plate is it worth the money?
 

First of all what is a restrictor plate? Can they be used on all FI applacations like ATI, Novi, Vortec etc. What are the pro's and con's.
What do you guys think about the restrictor plate Is it worth the money?
How much does it cost for one on a P1-SC. Your advice would be most helpful. I am looking for more performance. My car is already FI with stock LS2 internals.

:lurk:

Only thing I noticed is the smaller pulley they run. I have a 3.8.
It looks small compared to mine. I'm happy with mine. (in my sig)
Smaller pulley to raise pressure. But restricting volume with the plate.
giving away some eff. Then raising heat of some value. Lets hear from
others how they work. :cheers: :lurk:

I seems to work great on my car. I make 562 RWHP and 556 lb/ft.

As you can see, by 3500, the car is making 500+ ft/lbs.
http://i151.photobucket.com/albums/s...d/SC_Dyno2.jpg

I don't know if the same ECS restrictor plate used in the paxton kit will drop right into any blower kit's intake tube as they might be sized a bit differently, but you can certainly use A restrictor plate on a non-paxton kit. I'm sure Doug/Chris can give you more info on what you'd need. I THINK I recall them offering the plate for non-paxton cars.

From what i've seen, it looks like removing the restrictor plate on the Paxton kit yields about 2 more pounds of boost so I would think you could pulley down for about 2 extra pounds with the restrictor plate and end with similar power/peak boost to what your kit already produces, but with the added torque lower in the rev-range.

When I romp the loud pedal in my Vortech equipped car(Z06 rubber) the car really struggles to get traction even at 50-60mph! How difficult is it with 500 ft lbs at 3500rpm?

Will this Restrictor plate work on a P1-Sc? My car is making about 550 hp/500 fpt to the wheels with 6.9 lbs boost. What kind of increase could I expect? Is the Hp increase worth the money?
Or is there some other mod that is better dollar for dollar. what do some of you big horse power guys think? :bigears

Chris, Doug chime in here... :bigears


:lurk:

You are fine where you are and are not going to gain anything to speak of at your present boost level. :cheers:

I haven't floored my car since before the winter....I've blown the tires off at 70 MPH on a couple of occasions without even being able to get my foot all the way down.

Then again, I'm also on stock 285 supercars so those will be switched for something a little stickier next time. If this car actually had a sticky tire on it, it would be an absolute MONSTER with this torque curve. ;)

I have the beef outback 345's invos..Even with my NA setup @ 552 rwhp and 500 tq they cant keep up...:willy:

next Mod...
 

What do you guys think the next mod should be for my car... What would some of you do if you had the same set up. Car is 07 A6 z51, has Ati P1-SC intercooled,KB BAP. Long tube headers and borla catback with safe tune by Shawn Church. I do all the work myself so the labor is free so to speak. Your thoughts are appreciated.

:lurk:

:cheers:

I'm really happy with the way my set-up is working. I have the stock 6 rib. Considering the 3.90's and the Mustang numbers.
Most likely 600-610rwhp and 550 rwtq with stock gears on a dyno jet. Plan scary fast. No restrictor plate needed. I think the hard piping change is a great mod others are missing.

http://i251.photobucket.com/albums/g...scan0008-1.jpg

Anybody Ealse...

:)

Well, since no one else chimed in...
The restrictor plate is a restriction placed before the supercharger inlet; it is a universal device and can be put on any car, supercharged, N/A, Turbo, etc... Restrictor plates are used in Rally cars, in NASCAR, in Lemans, and other forms of racing for the purpose of artificially limiting how much power an engine can make.
In the context of Corvettes, restrictor plates are used to cap off the maximum HP your engine makes with a supercharger that is running a small enough pulley that the peak boost would otherwise be excessive (either for the safety of the engine internals, or for the limits of the fuel system, or for the traction available). The "trick" is to pulley the blower down one or two sizes and put a restrictor in front of it; because of the higher pulley ratio the blower starts making boost sooner so low end torque goes up, but then it hits a wall wherever the restrictor plate's airflow maxes out and the torque drops off along with HP. On the plus side you gain a lot of low end torque without making so much power that your engine is an inch away from its life, but on the minus side you ARE driving the blower harder, so belt tension and heat both go up. As far as I know ECS is the only shop using them right now.
A lot of people end up taking it off when they go forged or just want more power. A simple alternative is to run a smaller pulley; perhaps not quite as small as you would run with the restrictor plate, and then cap off the top end via a very conservative tune. Another option still is to run that small pulley and use methanol injection to keep the top end "safe". Again, it all comes down to you and what you want the car to do ;)

I believe Doug and Chris would tell you that they use the restrictor plate to bump up low end tq.

BJK

interesting topic. I know that it's old but exactly what i was looking for. I have a used A&A supercharger with a 3.4 pully. am looking for a 3.8 to lower the boost when someone said, "what about getting a restrictor plate" ...which brought me here.

I'm sure that a re stricter plate would be alot cheaper than the 100 dollar pully!

Your next mods should be to ditch the bap for a real fuel system, get meth, pulley down and a new tune. You'll find 100+ hpr with these mods. Parts cost appx $1500 plus retune. But this will lead you to buy a new transmission bc you will kill the stocker with the new found power.

Unless you intend to race liter bikes for money, stay with your current mods.

I've actually been struggling with this very thing....I can't get past the idea that he restrictor is forcing the supercharger to work harder when I could be using a wastegate to bleed off boost with no load penalty. The December GM High Tech touched on this but the data was skewed by a pulley swap where as I want to see it based against a restrictor. :toetap:

The problem is that you will likely need to make and design the plate yourself. I'm pretty sure the ECS air intake is different than the A&A, and I was told by ECS that their intake probably won't work with A&A's blower brackets due to head unit placement.

The restrictor plate is a very simple idea, but I do know ECS has done a lot of R&D to get the size exactly where they need for their head unit, pulley size, etc. Probably just be easier to swap the pulley, but you'll lose torque/power across the rpm range.

There is a very small "window of opportunity" when it comes to restrictor plates. We only use them in stock applications to raise tq, they are not used on forged or upper HP builds.
You can only cap a couple of lbs before the gains are out weighed by IAT's and it becomes inefficient. This window can be missed by a 1/16" of difference in the restrictor plate, so we cannot tell you what the optimal plate would be for another supercharger system other then our own where we have done countless hours of data logging and track testing.
When it is correct though, it is nice to have the upgrade options of a centri blower, with the equal hp/tq of a roots. Win-win :thumbs: