Tuning a TBucket Dart 400 cuin Engine
- Thread starter Indycars
- Start date
"You are showing "Time" along the horizontal bar, but asking for RPM....clarify please."
YES THATS NOT A MISTAKE,
yes much of the data is there , but it seems at least to me to be a bit difficult to decipher
and obviously you can only post what you have valid data to use , to make a cohearent graph from
A GRAPH, OF BOTH TIME SPENT IN EACH GEAR AND THE RPM RANGE THE ENGINE TRAVEL'S
THROUGH MAY BE HELPFUL.
Darn near, anything you can post, in graph form, taken from actual measured data
as far as
plenum vacuum vs rpm,
fuel/air ratio vs rpm
ignition advance curve vs rpm
car speed vs time spent in each gear
exhaust back pressure vs rpms
fuel pressure vs rpms
oil pressure vs rpms
or almost anything else you can post in a graph form to get a better understanding of exactly what is going on as the engine rpms and loads on the engine change can be very helpful in diagnosing the potential areas that are operating correctly and the conditions that can be modified to improve the over all performance and efficiency
YES THATS NOT A MISTAKE,
yes much of the data is there , but it seems at least to me to be a bit difficult to decipher
and obviously you can only post what you have valid data to use , to make a cohearent graph from
A GRAPH, OF BOTH TIME SPENT IN EACH GEAR AND THE RPM RANGE THE ENGINE TRAVEL'S
THROUGH MAY BE HELPFUL.
Darn near, anything you can post, in graph form, taken from actual measured data
as far as
plenum vacuum vs rpm,
fuel/air ratio vs rpm
ignition advance curve vs rpm
car speed vs time spent in each gear
exhaust back pressure vs rpms
fuel pressure vs rpms
oil pressure vs rpms
or almost anything else you can post in a graph form to get a better understanding of exactly what is going on as the engine rpms and loads on the engine change can be very helpful in diagnosing the potential areas that are operating correctly and the conditions that can be modified to improve the over all performance and efficiency
Since Grumpy wants Vehicle Speed in many of his graphs I decided the AQ1 should do that
for me. I did have to give up Oil Pressure so that I could record Vehicle Speed. I am limited
to recording 8 inputs.
My SpeedHut speedometer outputs 4000 pulses per mile, so I figured I should be able to
use that with the AQ1 and so did AEM.
I worked with AEM to develop the parameters that would work even thou it's not per the
manual. AEM wants pulses/rev of the driveshaft and it will only take whole numbers. So
AEM did some calculations based on my needs of 3.7:1 rear gear and 30.38" tire diameter
to come up with in the end the needed factor to get the right speed in MPH. AEM wanted
me to use 1 pulse/rev, 3.7 gear ratio and 18.5" for tire diameter.
My first attempt did not upload the new number 18.5 for tire diameter, it instead kept the
30.38. After I went back to verify and found the mistake, no matter what I did it would not
upload the correct value until I reboot the AQ1, then I had success.
The first graph shows my mistake with the tire diameter, I also recorded data at 1000/sec which
didn't seem to work well with all the spikes in the plot line for vehicle speed. It's at the very bottom
of the graph area.
This second graph below shows the vehicle speed as it should be. For the test I accelerated from a
stop light up to about 40 MPH and then maintained a constant speed, exactly like the plot shows for
vehicle speed.
Now Grumpy what kind of run should I make....standing start, medium to hard acceleration up
about 80 mph or what would you like to see? All eight inputs are recorded on every test run. It's
just a matter of which input to show on the graph. If it gets too crowded then I can always show
and 2nd or 3rd graph with the other inputs.
for me. I did have to give up Oil Pressure so that I could record Vehicle Speed. I am limited
to recording 8 inputs.
My SpeedHut speedometer outputs 4000 pulses per mile, so I figured I should be able to
use that with the AQ1 and so did AEM.
I worked with AEM to develop the parameters that would work even thou it's not per the
manual. AEM wants pulses/rev of the driveshaft and it will only take whole numbers. So
AEM did some calculations based on my needs of 3.7:1 rear gear and 30.38" tire diameter
to come up with in the end the needed factor to get the right speed in MPH. AEM wanted
me to use 1 pulse/rev, 3.7 gear ratio and 18.5" for tire diameter.
My first attempt did not upload the new number 18.5 for tire diameter, it instead kept the
30.38. After I went back to verify and found the mistake, no matter what I did it would not
upload the correct value until I reboot the AQ1, then I had success.
The first graph shows my mistake with the tire diameter, I also recorded data at 1000/sec which
didn't seem to work well with all the spikes in the plot line for vehicle speed. It's at the very bottom
of the graph area.
This second graph below shows the vehicle speed as it should be. For the test I accelerated from a
stop light up to about 40 MPH and then maintained a constant speed, exactly like the plot shows for
vehicle speed.
Now Grumpy what kind of run should I make....standing start, medium to hard acceleration up
about 80 mph or what would you like to see? All eight inputs are recorded on every test run. It's
just a matter of which input to show on the graph. If it gets too crowded then I can always show
and 2nd or 3rd graph with the other inputs.
I've tried to STANDARDIZE the graphs making it easier to understand at a glance what
is happening. Every parameter has a standard Min and Max value that will not change.
Therefore whether it two test done on the same run or whether it's two weeks later the
graphs will mean EXACTLY the same thing. I've put together the 6 parameters that could
tell us something in our quest for a better carburetor tune.
In the same order listed in the top right corner legend the standardized scale is:
VehSpd ........................ 0-100 mph
TPS ...............................0-90°
RPM ............................0-6500
MAP ............................0-15 InHg
AFR ............................ 10-18
Accel Longitudinal .... -0.5-1.5
For the graph below, the test run was done by doing the following. Put trans in 2nd gear,come to
a stop, accelerate hard enough to squeal the tires, let trans auto shift to 2nd (about 3500 rpm),
keep acceleration up and shift to 3rd gear, continue to about 80 mph then lift off the throttle ......
end of test.
Note: The vertical blue line and the value in the legend are at the same point in time.
is happening. Every parameter has a standard Min and Max value that will not change.
Therefore whether it two test done on the same run or whether it's two weeks later the
graphs will mean EXACTLY the same thing. I've put together the 6 parameters that could
tell us something in our quest for a better carburetor tune.
In the same order listed in the top right corner legend the standardized scale is:
VehSpd ........................ 0-100 mph
TPS ...............................0-90°
RPM ............................0-6500
MAP ............................0-15 InHg
AFR ............................ 10-18
Accel Longitudinal .... -0.5-1.5
For the graph below, the test run was done by doing the following. Put trans in 2nd gear,come to
a stop, accelerate hard enough to squeal the tires, let trans auto shift to 2nd (about 3500 rpm),
keep acceleration up and shift to 3rd gear, continue to about 80 mph then lift off the throttle ......
end of test.
Note: The vertical blue line and the value in the legend are at the same point in time.
Grumpy can you read the vertical scales and identify the plot for each one. Another
words, is there enough difference in all the colors to associate each one with the
legend and the scales???
For any further plots I don't have to include every parameter, which will simplify
and make it easier to read.
How do you want the test to be conducted??? If you need RPM on the horizontal
scale that might be a possibility, let me know so I can work on that graph. I will
need to export the data and pull it into Excel.
Is any of this going to be helpful, they don't look like the graphs that you were posting?
words, is there enough difference in all the colors to associate each one with the
legend and the scales???
For any further plots I don't have to include every parameter, which will simplify
and make it easier to read.
How do you want the test to be conducted??? If you need RPM on the horizontal
scale that might be a possibility, let me know so I can work on that graph. I will
need to export the data and pull it into Excel.
Is any of this going to be helpful, they don't look like the graphs that you were posting?
lets concentrate on a few basics first,
the fewer things we change at one time\
the easier it will be to see a change/cause and effect ,
and understand the relationship in performance that change made
lets take the fuel/air ratio line first, that should be a rather consistent and predictable transition from about 15:1 at idle to about 1500-1800 rpm then transition to about 12.6:1 from 1800-2000 rpm to about 5000 rpm where it remains rather consistent from there on up in the rpm band.
next your manifold vacuum, will generally fall rather predictably and consistently as the engine rpms increase, air flow demand through the carb increases but the area of the 4 venturies also increases reducing the flow restriction, while you may have a vacuum of 12-14 inches at idle youll have 1/3rd- 1/4 that at WOT
vehicle speed will be a bit faster once you get traction, but as speed increases the RATE of increase per second tends to slow
rpms will generally go from a launch, or converter stall of near 3000 rpm to about 6000 rpm where the trans shifting to the next gear ratio drops it,your 200r4 has these gears
200-R4.....................2.74.....1.57....1.0.....67
launch at lets say 2800 rpm
by the time you get traction,and reach
6000rpm /2.74/3.73=578rpm roughly 50 mph
shift
3450 rpm/1.57/3.73=580 rpm, roughly 50 mph
engine rpms build to 6000rpm
6000rpm/1.57/3.73=1024 rpm=roughly 90 mph
shift
3822 rpm/1/3.73=1024rpm=roughly 90 mph
engine rpms build to 6000rpm=
shift
OD GEAR
6000rpm/.67/3.73=2400rpm=200mph
yeah no one expects you to exceed 140 mph
but in theory the potentials there, but air resistance and aerodynamics makes it very unlikely
but getting in the low 11-high 10 second range should be do-able,
better tires(slicks) and some suspension work could easily gain you more
but the cost of meeting track regulations and adding a roll cage makes it not worth the expense and time & effort
http://web.archive.org/web/20070128173316/http://members.aol.com/powerrslid/thm2004r.html
http://www.wallaceracing.com/calcmph.php
http://www.wallaceracing.com/dragcalcquarter.php
http://www.wallaceracing.com/calc-rpm-drop-shift.php
http://www.wallaceracing.com/RPM Drop From Shift Calculator.php
the fewer things we change at one time\
the easier it will be to see a change/cause and effect ,
and understand the relationship in performance that change made
lets take the fuel/air ratio line first, that should be a rather consistent and predictable transition from about 15:1 at idle to about 1500-1800 rpm then transition to about 12.6:1 from 1800-2000 rpm to about 5000 rpm where it remains rather consistent from there on up in the rpm band.
next your manifold vacuum, will generally fall rather predictably and consistently as the engine rpms increase, air flow demand through the carb increases but the area of the 4 venturies also increases reducing the flow restriction, while you may have a vacuum of 12-14 inches at idle youll have 1/3rd- 1/4 that at WOT
vehicle speed will be a bit faster once you get traction, but as speed increases the RATE of increase per second tends to slow
rpms will generally go from a launch, or converter stall of near 3000 rpm to about 6000 rpm where the trans shifting to the next gear ratio drops it,your 200r4 has these gears
200-R4.....................2.74.....1.57....1.0.....67
launch at lets say 2800 rpm
by the time you get traction,and reach
6000rpm /2.74/3.73=578rpm roughly 50 mph
shift
3450 rpm/1.57/3.73=580 rpm, roughly 50 mph
engine rpms build to 6000rpm
6000rpm/1.57/3.73=1024 rpm=roughly 90 mph
shift
3822 rpm/1/3.73=1024rpm=roughly 90 mph
engine rpms build to 6000rpm=
shift
OD GEAR
6000rpm/.67/3.73=2400rpm=200mph
yeah no one expects you to exceed 140 mph
but in theory the potentials there, but air resistance and aerodynamics makes it very unlikely
but getting in the low 11-high 10 second range should be do-able,
better tires(slicks) and some suspension work could easily gain you more
but the cost of meeting track regulations and adding a roll cage makes it not worth the expense and time & effort
http://web.archive.org/web/20070128173316/http://members.aol.com/powerrslid/thm2004r.html
http://www.wallaceracing.com/calcmph.php
http://www.wallaceracing.com/dragcalcquarter.php
http://www.wallaceracing.com/calc-rpm-drop-shift.php
http://www.wallaceracing.com/RPM Drop From Shift Calculator.php
Last edited:
8
87vette81big
Guest
Actually all Rick needs to go Drag Racing. at a NHRA Sanctioned Drag Strip is a Helmet & if open faced hemet Goggles too.
And a Drivers seat belt.
Rick should not be having these problems.
The T is simple.
Its a fuel delivery issue.
Or the Demon carb.
Or the headers in place now.
Having a computer to diagnose is nice.
But it was not around to use 1940's - 2000.
Also the entire time I was on DC Grumpy not a single person drag raced thier car in 5-years.
The Bar has been set real high by the Hellcats Yes .
They are drag racing.
Should not stop any from drag racing.
Run what You Run.
Then they turn around and call me a Fony Mechanic.
I know I am Real.
I am back to Work now as Race Mechanic in a Performance shop.
I lost 4 months income meant for my projects.
I intend to Drag Race my cars.
Computer not required to Tune.
And a Drivers seat belt.
Rick should not be having these problems.
The T is simple.
Its a fuel delivery issue.
Or the Demon carb.
Or the headers in place now.
Having a computer to diagnose is nice.
But it was not around to use 1940's - 2000.
Also the entire time I was on DC Grumpy not a single person drag raced thier car in 5-years.
The Bar has been set real high by the Hellcats Yes .
They are drag racing.
Should not stop any from drag racing.
Run what You Run.
Then they turn around and call me a Fony Mechanic.
I know I am Real.
I am back to Work now as Race Mechanic in a Performance shop.
I lost 4 months income meant for my projects.
I intend to Drag Race my cars.
Computer not required to Tune.
8
87vette81big
Guest
And thinking about it this morning Grumpy,
The only to Make a You Tube Video Drag Racing thier own on Both Forums is RICK At the Hometown Street Race Nationals in Oklahoma .
All of DC Are Fonys.
The only to Make a You Tube Video Drag Racing thier own on Both Forums is RICK At the Hometown Street Race Nationals in Oklahoma .
All of DC Are Fonys.
8
87vette81big
Guest
Your Beating A Dead Horse unless you have a Fuel pressure input data logged.
this is the BEST YET!
8
87vette81big
Guest
It may be as simple as adding Holley Main Jet Extensions .
Bo Laws sells extra long length main jets.
Bo Laws sells extra long length main jets.
Nobody is saying yea or nae about reading the graph, so thought I would clear things
up at least one time.
Trying to tell when that shifts take place is difficult. The automatic trans and the car weight
are working against being able to tell. My best guess, the 1-2 shift occurs at 2.1 seconds.
No good guess on the 2-3 shift and the 3-4 didn't happen in this test.
up at least one time.
Trying to tell when that shifts take place is difficult. The automatic trans and the car weight
are working against being able to tell. My best guess, the 1-2 shift occurs at 2.1 seconds.
No good guess on the 2-3 shift and the 3-4 didn't happen in this test.
Last edited:
8
87vette81big
Guest
Grumpys Test Parameters are being Met.
I am interested in Acceleration G Force & Engine RPMS.
If You can do a 0-100 & 0-120 Mph Standing start my Critera should be met Rick to Diagnose further.
A 1/4 Mile Dragstrip pass on an abandoned 2-Lane Blacktop.
Always scope out the Test Road 1st.
I am interested in Acceleration G Force & Engine RPMS.
If You can do a 0-100 & 0-120 Mph Standing start my Critera should be met Rick to Diagnose further.
A 1/4 Mile Dragstrip pass on an abandoned 2-Lane Blacktop.
Always scope out the Test Road 1st.
8
87vette81big
Guest
I don't care when or where the 200 R4 shifts at. Leave it in Overdrive range.
Warm up the rear tires with a 20-30 foot long burnout.
Line it up straight.
Foot on the Floor and Give it Hell.
Don't forget to turn the Datalogger AEM ON.
Warm up the rear tires with a 20-30 foot long burnout.
Line it up straight.
Foot on the Floor and Give it Hell.
Don't forget to turn the Datalogger AEM ON.
Grumpy does and that's who I'm listening to right now!
8
87vette81big
Guest
That's Fine Rick.
I never have Datalogged any of my Carburated cars.
5.0 guys don't till they are in 8-second 1400 Hp Zone typically .
8
87vette81big
Guest
Maybe .
Faster than 8's gets real expensive unless you own a Shotgun Dragster or Build a Vintage Gasser Rail Car.
Also NHRA Upgrade the Race Roll cage.
25.3 Rule.
8
87vette81big
Guest
Be hard pressed to run legit 7's in a Steel bodied car or truck without spending $100,000 cash.
If a Corvette with IRS Rear about $200,000.
Stuff they don't tell you on the mainstream Forums Rick.
But I know.
At the 2,000 HP mark .
If a Corvette with IRS Rear about $200,000.
Stuff they don't tell you on the mainstream Forums Rick.
But I know.
At the 2,000 HP mark .
Ran another test this time from a standing start using the first 3 gears. Launching is alot
of spin, so I'm not using full throttle in 1st gear, trying to keep wheel spin under control
until I shift to 2nd gear. The 1-2 shift took place at 0.8 seconds on the graph. The 2-3
shift took place at 3.8 seconds, notice the dark green RPM plot line.
I had the speedometer record my 1/4 mile time of 12.96 seconds at 80 mph. Now I obtained
a max speed of 98 mph, so what happened is I went from 0-98, then coasted back to 80 mph
in 12.96 seconds.
The plug below have been in the car for a few weeks now during many of the tests. This
latest test was done on Route 66 and is about a 15 mile round trip.
What say you Grumpy, any suggestions???
of spin, so I'm not using full throttle in 1st gear, trying to keep wheel spin under control
until I shift to 2nd gear. The 1-2 shift took place at 0.8 seconds on the graph. The 2-3
shift took place at 3.8 seconds, notice the dark green RPM plot line.
I had the speedometer record my 1/4 mile time of 12.96 seconds at 80 mph. Now I obtained
a max speed of 98 mph, so what happened is I went from 0-98, then coasted back to 80 mph
in 12.96 seconds.
The plug below have been in the car for a few weeks now during many of the tests. This
latest test was done on Route 66 and is about a 15 mile round trip.
What say you Grumpy, any suggestions???