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This is just a VERY preliminary interim report, based on some early testing data done under very conservative conditions, as Lyndon works me slowly upward (we are being very cautious, due to the non-typical setup I have in my modified 04 SSR).

Attached are screen shots from my EFILive blackbox scanning. They document one run (run 011) done while commuting in to work this morning. I had to move the SSR off the shoulder into the travel line, and not hit WOT until I had some speed on in 1st gear, in order to prevent a complete loss of traction, so the run starts off showing low throttle / low speed and then you can see where the throttle setting goes to 100%.

The first image shows you a "dashboard" that the software constructs based on the logged data. This format allows you to "play" the run back as a real time event, OR step through it one frame at a time (0.1 second per frame in my case). This particular screenshot was saved after I paused the playback right after the vehilce hit 60 mph.

The second image shows you the "roll chart" format, where several of the key parameters are charted across the screen (time is horizontal axis), and again, you can analyze a static image, or manually "roll" the chart a frame at a time if you want. This particular image tries to show the entire run to 60 mph (and a bit past).

Several interesting things to note:

- There was abosultely no knock retard ever during the run.

- The MAP sensor actually registers during the run, but pegs at 30 as soon as you hit WOT.

- The 42 lb/hr injectors are actually hitting an 83% duty cycle. 80% is normally regarded as the desirable maximum duty cycle. This MIGHT be simply because Lyndon has set the air/fuel ratio on the very safe "rich" side for the time being. The alternative conclusion is that the engine is now, thanks to the supercharger, Z06 cam, and freeflowing dual exhaust, flowing WAY more air than we all anticipated.:)

- Those with a penchant for statistics will try to measure the 30 mph to 60 mph time. Save yourselves the trouble. I analyzed the TABULAR form of the data, and that 30 mph to 60 mph time is somewhere between 2.4 and 2.8 seconds. I say "somewhere between" because the datalogger dropped a couple of frames Lyndon thinks, when the data stream couldn't keep up with the rate of engine rpm increase. I think the 2.8 seconds is probably closer. Even this more conservative assumption means that the 0 to 60 will be mid 4s to high 4s at the WORST. Before supercharging, my 0 to 60, with a sort of "granny" start to protect the drivetrain, was 5.4 seconds. 1/4 mile was high 13s. So, I think we can now safely project high 12s easily.:)

The testing continues . . .

Jim G
 

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Discussion Starter #2
p.s. We are shifting the auto trans at 6200 in this run. Before supercharging, I was shifting it at 6500. Not sure yet how much higher than 6200 we can go with the supercharger.

Jim G
 

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great #s Jim!

I think:leaving
I don't really understand the tech stuff, but I get the impression that everythings working wonderfully:cool
I DID understand high 12s:thumbs
VERY IMPRESSIVE:flag
 

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So, I think we can now safely project high 12s easily.

Not without tires Jim, I know I can run mid 12's but no bite and you end up running 13.2's
 

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Double L: Here's my logic:

My UNsupercharged time to 60 mph was 5.4x. That was with a "granny" start that resulted in lousy 2.13 to 2.15 sec 0 to 30 mph times. If all I do is feather the throttle to keep the 0 to 30 mph NO WORSE than when unsupercharged, I7ll be getting to 60 mph at LEAST a 1/2 seond quicker than before supercharging.

But, the 0 to 60 mpg portion of a quarter mile run is the SMALL part of the run (took 5.4x seconds of the total 13.xx seconds). At speed above 60 mph, there is no traction problem. So, between 60 mph and the projected terminal speed of 112, the gain should e MORE than the 1/2 second gained in the 0 to 60 portion of the run. That means high 12s for sure.

My modeling software says that IF you could control the power transmitted to the ground, via astute throttle control, to prevent uncontrolled wheelspin, you can actually hit closer to MID 12s. The key is to NOT mash the throttle coming off the line. That won't work with these vehicles. You lose more than you gain once the wheelspin becomes uncontrolled.

Jim G
 

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I think I can figure out all the TLA (Three Letter Acronyms) on the screen, except IAT? Certainly (hopefully) not Intake Air Temperature, because it's 118F...
 

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13s with a Granny start

nothing wrong with that. Tire spin at WOT on start will not be controllable without a serious tire change.

It will be interesting to see how your on board computer compares to actual trap lights at a track.

Also will be interested to see how the mods work together for HP gains...Sum of mods HP gains or something greater.
 

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FriscoTX: That IS the intake air temperature!

It is measured at the mass air sensor. It illustartes the point I have been trying to make on this bopard for a long time: the underhood temperatures of the SSR are HIGH.

The reason the intake air temperature is so hot is that the incoming air is being preheated by the high underhood temperatures.

The actual AMBIENT temperature at the time this run was made this morning was 61 degrees Farenheit.:)

Jim G
 

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JimGnitecki said:
FriscoTX: That IS the intake air temperature!

It is measured at the mass air sensor. It illustartes the point I have been trying to make on this bopard for a long time: the underhood temperatures of the SSR are HIGH.

The reason the intake air temperature is so hot is that the incoming air is being preheated by the high underhood temperatures.

The actual AMBIENT temperature at the time this run was made this morning was 61 degrees Farenheit.:)

Jim G
WOW! In a moving vehicle...? The hood "underlip", all those foam seals, etc. would seem to bring ambient air in from way out front and therefore make under-hood less relevant...! WOW! 61F to 118F Not just WOW, but also YIKES!

Now I have to go REALLY LOOK at that whole area of the truck... I'd just been assuming, from the look of things, that we had a decent 'cold air intake' system. Hmmm...

With the CFM flowing through the airbox - MAF assembly - bellows - throttle body, I'm assuming that there will not be much heating due to contact with the walls... so insulating that path won't do much good... so it must be drawing hot air... we need to find a way to get it to draw COLD air.
 

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FriscoTX: Oops! I forgot the IAT got moved as part of the supercharger install!!

Joe (2005ssr6speed) reminded me by PM:

"
Jim

The intake air temp is moved to the rear portion of the intake when you installed the supercharger. It is the 2 wires that were removed from the MAF and they are relocated to the intake for a boosted temp reference to monitor and tune for boost easier. It is located just to the rear on the MAP sensor.

Joe
"

So, no, the UNcompressed incoming air temperature is lower I'm sure.

Mike Moro equipped me with a digital temperature measuring system some time ago, and I have been waiting for the right opportunity to find a suitable "passageway" for the wiring to pass through the firewall. Once I find a good passageway, I want to measure things like incoming air temperature, underhood temperature, temperature behind the heat exchanger, etc. so that we actually have some good data.

Vut, my comment still stands: the thermodynamics of that underhood area ARE really bad, and we do really need a cold air intake system.

Jim G
 

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Discussion Starter #12
Very observant, Mike!

The MAF was incorrectly graphing the MAP value versus the MAF value, and also using a ridiculously high maximum value for the scale as well. I must have somehow messed up the template file included in the EFILive software.

The attached image shows the corrected roll chart.

Note that the actual maximum value for air flow is almost 53 lb / minute. This was also shown in the dashboard image above which had been wired correctly to show the correct value and scale.

Being the jet engine instrumentation guy that you are, what does that 53 lb/minute of air and 83% of the 42 lb/hour injector capacity at that same rpm tell you about air / fuel ratio? I suspect that Lyndon would be running this pretty rich for safety while we test.

Jim G
 

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Ok Mike and others: here is the air / fuel ratio calculation (I think):

The 8 injectors each have a capacity of 41.67 lb / hour of fuel.
The peak usage, which occurred at the current shift point of 6200 rpm, was 83%.
So, we used 41.67 lb/hour x 8 x 0.83 = 277 lb / hour = 4.61 lb/minute.

Peak air flow also occurred at that 6200 rpm point, and was 52.6 lb/minute.

So, our air / fuel ratio was 52.6 / 4.61 = 11.4

As I said, Lyndon is being pretty conservative. The extra "richness" (more fuel per pound of air) helps to cool the combustion process and helps ensure no detonation.

Think about the following a bit: Gas weighs about 6.15 lb/gallon (varies a bit with temperature, formulation, and other variables). So, the 4.61 lb/minute of fuel being used at WOT is equivalent to 0.75 gallon per minute!! This should give everyone some idea of:

- why acceleration bursts hurt fuel mileage so much
- the degree of mechanical violence going on inside that engine at WOT.

Also consider the following:

At 6200 rpm, you get 6200 / 2 = 3100 complete cycles of a 4-cycle engine within each minute. That means 0.01935 second to COMPLETE each intake-compress-burn-exhaust cycle.

We are on my engine using up 83% of that 0.01935 second (that's what it means when we say that the inector is operating at 83% duty cycle). So, the poor injector gets only 0.016 second to inject its entire shot of fuel for the next cycle. nd, it has to repeat this performance, reliably, and absolutely consistently, 52 times per second. THAT's impressive.

Jim G
 

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JimGnitecki said:
Double L: Here's my logic:

My UNsupercharged time to 60 mph was 5.4x. That was with a "granny" start that resulted in lousy 2.13 to 2.15 sec 0 to 30 mph times. If all I do is feather the throttle to keep the 0 to 30 mph NO WORSE than when unsupercharged, I7ll be getting to 60 mph at LEAST a 1/2 seond quicker than before supercharging.

But, the 0 to 60 mpg portion of a quarter mile run is the SMALL part of the run (took 5.4x seconds of the total 13.xx seconds). At speed above 60 mph, there is no traction problem. So, between 60 mph and the projected terminal speed of 112, the gain should e MORE than the 1/2 second gained in the 0 to 60 portion of the run. That means high 12s for sure.

My modeling software says that IF you could control the power transmitted to the ground, via astute throttle control, to prevent uncontrolled wheelspin, you can actually hit closer to MID 12s. The key is to NOT mash the throttle coming off the line. That won't work with these vehicles. You lose more than you gain once the wheelspin becomes uncontrolled.

Jim G
Well you never know till you get to the strip, As far as feathering the throttle, You will never win a race, R/T would be awful, Did that, The only way to run a SSR like we have is come off the line at idle, Don't nail it but don't take all day either, I don't like to just test the truck and lose the race, You will most likey spin the tires all way through 1st. but a good drag strip like we have is very sticky, Some times it wants to come around with you when it hits 2nd. if you have a good tranny with t/c so I don't know about the 60 mph being a safe no wheel spin, All I know is from 40 years of racing is you don't know anything till you get the car on the track, I would love to race you and 6speed, To see two SSR's race each other would be fun, I get tired of racing Ford lightings and Dodge Hemi's
 

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JimGnitecki said:
Ok Mike and others: here is the air / fuel ratio calculation (I think):

The 8 injectors each have a capacity of 41.67 lb / hour of fuel.
The peak usage, which occurred at the current shift point of 6200 rpm, was 83%.
So, we used 41.67 lb/hour x 8 x 0.83 = 277 lb / hour = 4.61 lb/minute.

Peak air flow also occurred at that 6200 rpm point, and was 52.6 lb/minute.

So, our air / fuel ratio was 52.6 / 4.61 = 11.4

As I said, Lyndon is being pretty conservative. The extra "richness" (more fuel per pound of air) helps to cool the combustion process and helps ensure no detonation.

Think about the following a bit: Gas weighs about 6.15 lb/gallon (varies a bit with temperature, formulation, and other variables). So, the 4.61 lb/minute of fuel being used at WOT is equivalent to 0.75 gallon per minute!! This should give everyone some idea of:

- why acceleration bursts hurt fuel mileage so much
- the degree of mechanical violence going on inside that engine at WOT.

Also consider the following:

At 6200 rpm, you get 6200 / 2 = 3100 complete cycles of a 4-cycle engine within each minute. That means 0.01935 second to COMPLETE each intake-compress-burn-exhaust cycle.

We are on my engine using up 83% of that 0.01935 second (that's what it means when we say that the inector is operating at 83% duty cycle). So, the poor injector gets only 0.016 second to inject its entire shot of fuel for the next cycle. nd, it has to repeat this performance, reliably, and absolutely consistently, 52 times per second. THAT's impressive.

Jim G

Jim things look real good for a starting point on a large project like yours...One thing I did notice is the injectors working pretty hard...I mean that from my racing experience with the turbo Buick which was in the 10's and completely streetable is the 83% duty cycle is a bit hard on the injectors. I worked with Bosh with my buick and they always insisted we not exceed the 60-66% duty cycle for two reasons. One is the injector wears our sooner and the injector gets inconsistant with age and longer duty cycle. At the time I lived in Greenville, SC and Bosh was located there making the injectors. Those guys took my project on like it was their own and really impressed me with their knowledge of business. Just a thought I had when I read your post...Congrats and keep it pointed in the right direction!!!:jester :jester
 

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Discussion Starter #17
srpbaer: Yes, I know that duty cycle is high. EFILive recommends 80% as the "peak" (at high rpm where you don't spend much time) with modern injectors (I guess they have come a ways).

What puzzles me is that I should NEEDING that high a fuel rate. These are after all the same injectors (42 lb/hr) as are used in the LS2 SSR Magnacharger kits (for the 05 / 06 SSRs)! Can my highly modified 04 SSR really be flowing so much air that I need larger injectors than supercharged 05 / 06 SSRs do??

Remember that the 05/06 SSRs have better heads, larger valves, a larger (90mm) throttle body, and 13% more dispacement.

On the other hand, I have:

- a better cam (02 Z06 cam) which has a bit more duration and LOT more lift than their cams (which are similar to the 01 Z06 versus 02 Z06 cam)

- a vastly better exhaust - true dual and VERY free flowing exhaust, & Dynatech Supermaxx headers with hi-flow cats

I don't want to dyno the vehicle until I have done a lot more testing and datalogging, and until I have had the transmission strengthened (currently scheduled for 3-30 and 3-31 at Phoenix Transmissions in Weatherford).

Still testing and monitoring . . .

Jim G
 

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JimGnitecki said:
srpbaer: Yes, I know that duty cycle is high. EFILive recommends 80% as the "peak" (at high rpm where you don't spend much time) with modern injectors (I guess they have come a ways).

What puzzles me is that I should NEEDING that high a fuel rate. These are after all the same injectors (42 lb/hr) as are used in the LS2 SSR Magnacharger kits (for the 05 / 06 SSRs)! Can my highly modified 04 SSR really be flowing so much air that I need larger injectors than supercharged 05 / 06 SSRs do??

Remember that the 05/06 SSRs have better heads, larger valves, a larger (90mm) throttle body, and 13% more dispacement.

On the other hand, I have:

- a better cam (02 Z06 cam) which has a bit more duration and LOT more lift than their cams (which are similar to the 01 Z06 versus 02 Z06 cam)

- a vastly better exhaust - true dual and VERY free flowing exhaust, & Dynatech Supermaxx headers with hi-flow cats

I don't want to dyno the vehicle until I have done a lot more testing and datalogging, and until I have had the transmission strengthened (currently scheduled for 3-30 and 3-31 at Phoenix Transmissions in Weatherford).

Still testing and monitoring . . .

Jim G


You pose some good questions about should you be needing larger injectors!!!. I would venture a guess that you could be pumping more air that the 05 with JUST the Magnscharger. After all you have much better exhaust and the engine is as we have always heard "just a big air pump"!!!!! I think I was running 64lbs injectors in the Buick and pushing 22lbs of boost so you may not be on the wrong track!!!
Good Luck:seeya
 

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Discussion Starter #19
Hey guys and gals: Remember, my SSR is very non-stock. Isn't it impressive how well Lyndon Wester dialed in his very first supercharged tune for it?

Those of you with 03 and 04 SSRs now should be clearly able to see that the limit for performance on the LM4 engine is NOT the 350 rwhp or so available by simply adding a Magnacharger kit to a stock LM4.

And remember, this is still my daily driver, it still idles at 600 rpm, and if you look at my fuel mileage thread from the other day, you'll see that it STILL gave me 18.8 and 19.1 mpg commuting into work two mornings in a row.

Shows how good the technology of these engines is, and how well things go when you work with really good people like 2005ssr6speed, Lyndon Wester, and Randy Peurifoy. Thanks all 3 of you. You've exceeded my hopes and expectations.:)

Jim G
 

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JimGnitecki said:
FriscoTX: Oops! I forgot the IAT got moved as part of the supercharger install!!

Joe (2005ssr6speed) reminded me by PM:

"
Jim

The intake air temp is moved to the rear portion of the intake when you installed the supercharger. It is the 2 wires that were removed from the MAF and they are relocated to the intake for a boosted temp reference to monitor and tune for boost easier. It is located just to the rear on the MAP sensor.

Joe
"

So, no, the UNcompressed incoming air temperature is lower I'm sure.

Mike Moro equipped me with a digital temperature measuring system some time ago, and I have been waiting for the right opportunity to find a suitable "passageway" for the wiring to pass through the firewall. Once I find a good passageway, I want to measure things like incoming air temperature, underhood temperature, temperature behind the heat exchanger, etc. so that we actually have some good data.

Vut, my comment still stands: the thermodynamics of that underhood area ARE really bad, and we do really need a cold air intake system.

Jim G

That 118F number make much more sense if it's post-boost (and post intercool, I assume).

Also, I did go take a good look a the intake, with the hood closed & a flashlight. There are some opportunities to "spruce up" the stock system. Big hole around the hood latch. Big holes at either side. It's raining in North Texas this weekend, and I may spend some time with sheet plastic, tin snips, weatherstrip foam, and tape/glue tomorrow...
 
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