RJC Power Plate

I took the time again to find an old post or two, which pretty much sold me on the plate:

Here they are:
Here are the before and after egt readings with the Precision plenum and a RJC plate. The egt probes are located in the header aprox. one inch from the mounting flange.

(without plate) (with plate)

(1 1702) (1 1660)
(3 1688) (3 1640)
(5 1759) (5 1647)
(2 1736) (2 1704)
(4 1744) (4 1707)
(6 1802) (6 1682)


These readings are taken at the end of the 1/4 mile pass on a motor with 9.5 CR, 24 degrees timing, 27 boost, 11.5 a/f.
The 1/4 times didn't pick up or fall off by adding the plate, as you can see it evens out the air lowering temps.

I was one of the critics when I first saw it until Brian Scott (turbobuick) gave me his to try out at Norwalk now I am sold on it.

I heard all of the 9 sec. and low 10 sec. tsm cars were using the plate at BG this year(not sure what yr because old post), all were taken home with head gaskets intact.
Dave Bamford

Then you have an old post from Nick Micale:
Here is info based upon real world experience.

Install a power plate on a NHRA stock motor on a dyno, NO other change, 25 ft-lbs increase in the torque band.

And Jason isn't afraid to post the dyno of a plate addition:
http://rjcracing.com/RJC_Buick_Products/RJC_A_D__Power_Plate/dyno_chart/dyno_chart.html

Along with Jason's testing on someones car: http://www.rjcracing.com/RJC_Buick_Products/RJC_A_D__Power_Plate/Tracktest/tracktest.html
 
Hemco plenum/RJC plate

Has anyone compared the Hemco style plenum with the RJC plate? Supposedly: it balances out the flow between cylinders as well. I'm not talking about one with a larger TB(that would slow down the charge velocity), but rather: a stock size, so as to compare apples to apples. I'm considering one and wondering if it's worth it(compared to the RJC piece). Any input will be appreciated.:cool:
 
all intakes for the 3.8l engines will need some sort of crutch to even flow. It has to do with the plenum design. Ever wonder why the sheet metal intake plenums are so different to the stocker.
 
Supposedly- the Hemco IS a redesigned plenum that simulates a center-top-mounted throttle body(rather than front-mount), and more evenly distributes the airflow to the cylinders. Anyone have any experience, or done any comparisons with the piece?
 
Jesus Christ there are some frickin' ignorant people here. I'm not going to mention names but the ones talking out their asses know who they are.

The damn thing works, its been tested and proven, anyone who doesn't believe it probably has to wear velcro shoes to avoid the complexity of having to tie their laces.

Please, everyone, use the damn search button. I promise you 90% of your questions have been asked before.
 
Originally posted by Ormand
If you can figure out a way to change the flow of air, or any fluid, without affecting pressure, you will have accomplished two things.
First, you will have figured a way to get around the laws of nature. (or Newton, if you prefer)
Second, you will have made yourself richer than Bill Gates.
There is- HAS to be- a small pressure drop across the PP. But it is not large enough to offset the gains it gives from improved flow distribution.

Ormand you are right on IMO. One of the best ways to see this effect IMO (that we could afford ;) ) was to put an inline MAF sensor and test with and without plate, using the same air source. I measured a very small decrease in MAF with the plate, compared to w/o. Like 4.90-4.92v without the plate, 4.88v with it on a 5v F*rd MAF. IMO the benis likely outweigh any slight restriction, and of course on turbo cars we can usually compensate by adding 0.10 more psi boost if need be ;) (assuming it isn't already maxed out of course)

Anyway, that's the result we saw in our testing so far. The air source we had was only capable of about 300 hp MAF flow though, roughly.

TurboTR
 
heres the data from a test of the plate on a PTE plenum
http://www.vortexbuicks-etc.com/plenum_comparison.htm

even if it is restrictive (im not saying it is or isnt but it appears to has more open area than the TB so idont see how it is a restriction ) anything that balances the cylinders will provide more power and run smoother and safer since the rear cylinders wont be leaned out , I wont run without one and it allows for more boost without KR so just crank it up and enjoy the ride (which will now be shorter :) )

only con to using the plate i found was the two studded bolts from the stocker arent quite long enough to get the proper torque without possible damage to the threads it does grab and should be replaced with longer bolts ,
 
Thanx for the URL to that comparison Pacecarta. That's the kind of stuff I was looking for- VERY informative!!;) Now I know what my next move is!:cool:
 
Well- looks like the Hemco plenum is a helluva lot better than the stocker, but nowhere near as balanced as the PTE plenum and plate. Looks like a no-brainer(perfect for my mentality, or lack there-of)!! Thanx again Pacecarta, Al:cool:
 
If some cylinders get more air, than USE IT! Don't fight it. Get a sequential and add fuel in those cylinders. That will be better than just blocking the flow. I'm not knocking the Plate for what it was intended for, but for racing, I think a faster way exists. Does this make any sense?
 
Thats fine and certainly feasible but $60 for a plate vs. a $1800-2300 FI system along with a $$$ 6 channel egt(unless FAST or BS3 can do it) to have data to even be able to work to tune those cylinders w/ more airflow and even then you have to make several passes to get the tune in vs. bolting on a plate in 20 min and establishing much more even air distribution and power production across all cylinders.
 
Originally posted by BoostKillsStres
Thats fine and certainly feasible but $60 for a plate vs. a $1800-2300 FI system along with a $$$ 6 channel egt(unless FAST or BS3 can do it) to have data to even be able to work to tune those cylinders w/ more airflow and even then you have to make several passes to get the tune in vs. bolting on a plate in 20 min and establishing much more even air distribution and power production across all cylinders.

Agreed. If you have the time and funds, a custom intake would be the best solution. You could balance the flow any way you see fit. The plate is what it claims, and is way to simple to use.
 
If some cylinders get more air, than USE IT!
Sorry, it just don't work that way! Think about this. The rear cylinders get more air. So the pressure in the rear cylinders is higher. That means that those cylinders detonate first. So, if you use any method to get the right fuel to the rear cylinders, ANY method, they will still be limiting. They will reach the knock point WAY before the front cylinders do, because they have the most air. The PP limits flow to those cylinders, so that you get EVEN distribution, and all six cylinders will get close to the knock limit (closer, anyway) at the same time. Your engine will make more power, and be smoother, with close to the same power from each cylinder. With FAST, or any system that balances fuel flow to match the air flow, you will have two cylinders making max power, two making least, and two in between. Not good for power, and surely not good for smooth. So, even if does restrict flow, to some extent, the PP is still a net improvement over stock, and I think over the Hemmings, too.
 
Well, I'm having Cotton build me a stage motor for a little racing. I already have a sequential, and most all other stuff (need multi-channel EGT). I am not worried about knock with 117octane. I hope to get a "master tuner" helping. Jack, Cal, and Andreson are sometimes floating around here. When you are this far in the game, I surely don't think $40 piece of metal is going to be the finishing touch on my $17,000 motor. I'll be glad to try it, it's cheap. But I'm going to try to get the most out of it, and blocking air is not in my game plan. I use the RJC plate on the street with OEM computer. That makes sense. How many TSO guys do you think run a plate?

I love RJC stuff. I have plenty of his products. I think his new boost gizmo is pretty trick, and half or 1/3 the price of similar products.

I hope the Champion intake is better than you guys think.
 
Turbo2nr, you are not getting the point! Doesn't matter WHAT fuel you are using, bad distribution HURTS POWER! You can use 100 octane, or 110, or 117, or 120, the answer is still the same. At some boost level, you WILL get detonation. If you don't have good distribution, that means one or two cylinders will detonate way before the others,and you will make less power, and the engine will be rougher, which also means it is more likely to break.
Seems like you have lots of money, but may not be spending wisely? If you think a $40 dollar part makes no difference, then maybe you ought to ask your machinist to put that engine together with OEM bolts, instead of the more expensive kind.
Heres a real simple explanation.
For 17,000, you ought to get at least 600 horsepower. That would SEEM to be 100 per cylinder. But without the PP, it will mean an AVERAGE of 100 per cylinder. Weak cylinder may make only 95, while strong cylinder makes 105. So, the MAX the engine would do is 6X105, if all cylinders were getting full flow. That would 630 hp, instead of 600. If you restrict flow to the strong cylinder, so it only makes 100 hp, the air will go to the weak cylinder, which now makes 100 hp. You will have the same 600hp you had to start with, but with a smoother engine. AND, you can turn up the boost just a tad, since the cylinders are actually capable of 105 each, and end up with MORE power, because of adding a $40 restriction!
 
I think that alot of people are looking more at the "restriction" of the plate from just looking at it. If you were to measure the open area of the PP and a 70MMTB you will more than likely find that the TB has a 30% smaller open area than the PP does. So that means the most "restrictive" part in the intake even with the PP installed is the Throttle Body itself. That was one of the things that made me put one on my car so it can even the air distribution within the manifold to keep the back cylinders from leaning out. I was able to squeeze like 1-1.5lb more boost on the same fuel and I firmly believe that is because of not leaning the back 2 cylinders out and not because the PP is "restrictive". Just my .02:)
 
So are you just guessing, or are you sure the PP opening is larger than the area of a 70mm round hole. I think you are wrong. But I haven't measured it.
 
I'm far from an expert on these cars, but if guys are running 9s with the plate, you probably shouldn't be worried about it being a restriction if you are running 10s, 11s or 12s.

With some of the worse flowing heads I have seen a in a while, That was something I was more concerned about vs the RJC plate. I'm sure it restricts air the same the as throttlebody, intake & heads restrict it, but if it doesn't become a problem until a car is in the 9s, 90+% of us should be happier with the fact that the engine has much better balance.
 
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