01black

iTrader: (4)

i think im having a fuel psi issue with my N20 outlet plate...14.5 afr at 5600ish

as long as the pattern atomizes (ample fuel psi) it seems to hit HARD...least it did before my cam swap.....i have a racetronix 255 in mine w/o the harness, just the pump itself...seems like its not keepin up where it needs to be ...goin to a stand alone fuel kit for it asap...

01black

iTrader: (4)

so it blows how many cylinders on the way in...1 2?

383LQ4SS

iTrader: (33)

Actually...Im not so certain a perfect 360 pattern will allow for better distribution. Its really impossible to say....atleast for fuel.

It would take real testing with some good equipment in order to make a claim to which is better. But let me just throw this out there. How many have seen the inside of an LS6 or FAST intake. Each runner inlet faces the bottom of the plenum and the air has to go down to the bottom of the plenum and and then turn sharply upwards. So a perfect circular pattern aimed toward the back center of the plenum may in fact not be better than a bottom out pattern that aims the denser fuel in the area of the intake port inlets. Fuel flow along the floor is more critical than down the center. But again...IMO its impossible to say.

I used to have 8 EGT datalogger in my old direct port and got ALOT of info from using that. Someone should do a check...especially if anyone wants to make a claim. Claims should be backed up . But again...I dont think the differences between kits will amount to much. As we have seen so many times...the differences between kits many time amount to "negligable" differences.

Beaflag VonRathburg

iTrader: (176)

How much does a setup like that go for and what did you use specifically?

383LQ4SS

iTrader: (33)

alltronics Red Alert 8 EGT datalogger $999 with Kooks 1 7/8 stepped to 2" primaries with the EGT bungs welded in.

Beaflag VonRathburg

iTrader: (176)

That looks pretty sweet I'm going to have to look it up.

Robert56

iTrader: (2)

Yea, the below the runners plenum is one of the reasons that a nozzle or plate wet kit is less than perfect, and the reason a dry works better. Al, what temp differences did you see before and after DP tuning? You no longer have your EGT set-up? I still contend that a 360* may in fact have a much more equal mix because of the the fuel and n2o being released evenly around the perimeter, it evens out no matter how the air flow hits it. Whereas, the other methods if you have a higher density off to one side this leads to an unequal mix going into the intake. Well, like I said before it's all speculation at this point, but seems to me to have merit.

Robert

SmaknaSS

iTrader: (1)

Nice. That looks real clean for all the stuff you have on that engine. That real cool that you can see the A/F ratio and temp from every primary.
BTW, is that a 99 Camaro that that engine sits in? I can see the back of your engine real easy like a Vette. My engine is almost half way covered in my 01 Camaro.

383LQ4SS

iTrader: (33)

Robert..I am with you on the dry. But I do like the plates better than a single nozzle. Now for the differences and which may be better...you can make a case for either or. But without testing..its just hypothesis.

But I would just say the differences are probably negligable..as I said before.

On the EGt I would see up to 100 degrees difference at times. Funny thing...at part throttle driving is where the temps are the greatest variance. These intakes change characteritics with flow. The engineers have to cover all bases. But at GM for an LS1 the bases they need to cover range between idle and WOT at 6200 rpm on a tyical LS1. At low flow cylinders vary greatly (part throttle). As you start to flow more air things change..at WOT the EGTs would begin to tighten up as far as variance. And then it would change even further...as you went up in cam size and head flow or even cubic inches the flow changed again causeing different EGTs. Because if you have a FAST 90 and a cam only setup..the way the air flows through the intake will vary greatly when you add heads...and vary even more when you add 60 cubic inches. The intake remains the same. But flow varies greatly.

The way the air flows through these EFI intake varies GREATLY from idle on a stock LS1 all the way to WOT at 7500 RPM with a 260/272 .714/.733. Lean cylinders can change place due to these variances.

For instance...this is an NA run. Note how at low rpm cylinder #3 the green line is WAYY higher EGTs than the light purple cylinder #6. But during the run they swap places. Also note how they come together for the most part. Thats because the engineers know that the critical area is at WOT at higher rpm...or peak Tq. Being lean on some cylinders at part throttle or idle isnt a dangerous condition.

And all that is just for air. Add fuel into that mix in the form of a nozzle or plate kit...and things change even more drastically.

As a matter of fact...I would be willing the bet the difference in AF per cylinder caused by the design of these plates are probably less than the differences caused using either plate on a car with say a completely stock LS1 VS a heads, large cam, FAST 90 setup. I hope that makes sense.
And of course..as you said..the only way is to test it with either wideband per cylinder (prefered) or 8 EGT datalogger.

Robert56

iTrader: (2)

Al that's one killer EGT application. Did you fine tune each cylinder on the above, or is this with the factory jetting rec, or at least all the same size? Man, if only I had a dyno in my garage... (By the way, I have an on call free dyno session for some dry tuning @ TTi's facility, ready to cash this perk in, if ya know what I mean on the other thing...)
Robert