Well I finally got to do some testing of the RJC Racing BGC ADPP. Note that we only had about 600 cfm of source airflow, roughly, from a flow bench. On the real engine it probably sees at least 2x that. Basically we were feeding the air into the inlet piping as it all exists on the car, connected where it comes out from the fmic exit. We used an aftermarket F*rd MAF to measure the total MAF. Used a sensitive differential pressure gauge to measure the steady state pressure difference rear to front in the manifold, and the steady state pressure difference from top to bottom (across the plate basically). Also did some rough hand pitot probing of each port and mapped that. And then sprayed the N2O while the air was also flowing through the system and took pics of the resulting spray patterns from the ports. Tested with and without the plate of course.
I'm estimating we had about 30 lbs/min of flow through the system The MAF read ~ 4.90v (out of 5v max). Of course the real engine sees on the order of 2x+ that, like 80+ lb/min. But what we had was still enough to blow all the papers and nekkid chicks calendars off the walls (lol) from the air rushing out of the rear ports (with no plate)...
Here are some pics of the test setup, taken with my phone camera which is obviously not very good
(edit- the board does not allow many images to be linked- Grrrr... So some are linked instead)
http://www.geocities.com/turbotk2001/BGC_ADPP_testing/BGC_ADPP_test_setup_a.JPG
The intake appears to have had a hysterectomy (lol) because it was converted from off center to on center awhile back (by list member Bad as L). Cut it lengthwise and put it back together basically. It has a pressure tap in the front, and I also added a tap in the the rear for the tests.
We found that, with the plate the overall flow balance across the ports was very good; a bit forward port biased at our test flow level. Maybe at a more realistic flow level (like 2x) the balance would equalize even more, as much higher dynamic force towards the rear should occur. One thing I found very interesting is that without the plate the flow was so skewed that the flow direction from the #2 port up front was actually reversed, flowing INTO the port from the outside while the others were blowing out hard (lol). Overall, without the plate the flow was of course heavily biased towards the rear ports. Not a pretty situation at all actually IMO This can be seen quite graphically in the pics below.
With no plate I measured +6" H20 (~0.2 psi) pressure delta from the rear to front of the manifold at our test flow. At 80 lbs min that would surely be much more; probably on the order of +0.5 psi or more. The sensitive 6" H2O gauge I had turned out to be about perfect for these tests. Also used it for the pitot probing. Anyway, when the plate was put on that pressure delta dropped to about +0.5" H2O or less, rear to front.
I for sure like the positive effects it had on the nitrous flow, at least as I see it. While the air was blowing through we shot a ~ 150 dry shot. On my setup the hose ports into the inlet piping down low, near where the pipe turns up from the fmic exit. I've always been curious as to what exactly comes out the ports when the hose is on, and how well it balances. The pictures below tell the story there quite well IMO...
Here is the nitrous flow out of the ports without the BGC ADPP. The majority of it can be seen clearly blowing out the rear holes only:
Here is the flow with the BGC ADPP; the flow is very much equalized:
Whew that industrial grade nawwzzz stinks lol...
Of course all this testing is basically dealing only with the steady state component of the flow, and maybe does not tell us as much of the whole picture as we would like. Still mulling all that over, and likely will be for the next several years I'd suspect that as the engine speed (and the flow) increases, the steady state flow aspects become relatively more and more heavily weighted in the total picture. But still very interesting tests, regardless.
I will definitely use the plate Good work RJC!
TurboTR
I'm estimating we had about 30 lbs/min of flow through the system The MAF read ~ 4.90v (out of 5v max). Of course the real engine sees on the order of 2x+ that, like 80+ lb/min. But what we had was still enough to blow all the papers and nekkid chicks calendars off the walls (lol) from the air rushing out of the rear ports (with no plate)...
Here are some pics of the test setup, taken with my phone camera which is obviously not very good
(edit- the board does not allow many images to be linked- Grrrr... So some are linked instead)
http://www.geocities.com/turbotk2001/BGC_ADPP_testing/BGC_ADPP_test_setup_a.JPG
The intake appears to have had a hysterectomy (lol) because it was converted from off center to on center awhile back (by list member Bad as L). Cut it lengthwise and put it back together basically. It has a pressure tap in the front, and I also added a tap in the the rear for the tests.
We found that, with the plate the overall flow balance across the ports was very good; a bit forward port biased at our test flow level. Maybe at a more realistic flow level (like 2x) the balance would equalize even more, as much higher dynamic force towards the rear should occur. One thing I found very interesting is that without the plate the flow was so skewed that the flow direction from the #2 port up front was actually reversed, flowing INTO the port from the outside while the others were blowing out hard (lol). Overall, without the plate the flow was of course heavily biased towards the rear ports. Not a pretty situation at all actually IMO
This can be seen quite graphically in the pics below.With no plate I measured +6" H20 (~0.2 psi) pressure delta from the rear to front of the manifold at our test flow. At 80 lbs min that would surely be much more; probably on the order of +0.5 psi or more. The sensitive 6" H2O gauge I had turned out to be about perfect for these tests. Also used it for the pitot probing. Anyway, when the plate was put on that pressure delta dropped to about +0.5" H2O or less, rear to front.
I for sure like the positive effects it had on the nitrous flow, at least as I see it. While the air was blowing through we shot a ~ 150 dry shot. On my setup the hose ports into the inlet piping down low, near where the pipe turns up from the fmic exit. I've always been curious as to what exactly comes out the ports when the hose is on, and how well it balances. The pictures below tell the story there quite well IMO...
Here is the nitrous flow out of the ports without the BGC ADPP. The majority of it can be seen clearly blowing out the rear holes only:
Here is the flow with the BGC ADPP; the flow is very much equalized:
Whew that industrial grade nawwzzz stinks
lol...Of course all this testing is basically dealing only with the steady state component of the flow, and maybe does not tell us as much of the whole picture as we would like. Still mulling all that over, and likely will be for the next several years
I'd suspect that as the engine speed (and the flow) increases, the steady state flow aspects become relatively more and more heavily weighted in the total picture. But still very interesting tests, regardless.I will definitely use the plate
Good work RJC!TurboTR
