K1100 16v NA intake & exhaust sims ( and power estimate)
Turbo Mini Forums

Hi.

I'm planning my NA build (maybe turbo later, have to walk before warp drive) and have come up with the following specs for the intake and exhaust using pipemax (Larry Meaux).

it does BHP and torque estimations as well which tend to be quite acceptable ( it was within 1 hp when you input the BMW K100 data).

the input data still has a few things that need to be more accurate. the cam timing is a guessed as the BMW figures are at a lot of lift and not 50 thou. furthermore the VE data is a bit of a guesstimation based on the VE as needed to get factory specs (104% which seems about right). the posted max flow of 150 CFM at 10.5mm lift would suggest that a this estimate is at the conservative side.

well, i hope this is of interest of someone even if it is NA and not charged:


I could use some better numbers for the camshafts

does anyone have better numbers for duration at 50 thou ?





************** Metric Units ******************

1.359 Liters @ 7500 RPM with 103.6 % Volumetric Efficiency PerCent

Required Intake Flow between 56.1 L/S and 58.8 L/S at 71.12 CM
Required Exhaust Flow between 44.2 L/S and 47.8 L/S at 71.12 CM

600 RPM/Sec Dyno Test Lowest Low Average Best
Peak KiloWatts 90.5 94.2 96.1 98.0
Peak Torque Ntn-Meter 127.7 132.9 135.6 138.2

Kilowatts per Liter 66.6 69.4 70.7 72.1
Torque N/M per Liter 94.0 97.8 99.8 101.7

BMEP in Kpa 1181.0 1229.6 1253.9 1278.2
Carb L/S at 38.1 MM Hg 88 98 103 108

Target EGT= 737 degrees C at end of 4 second 600 RPM/Sec Dyno accel. test
Octane (R+M)/2 Method = 93.2 to 95.6 Octane required range
Air Standard Efficiency = 61.03440 % for 10.190:1 Compression Ratio


( Metric Units ) ( per each Valve Sq.CM area )
Engine Size Liters = 1.359 Intake Valve Net Area = 5.203
CC per Cylinder = 339.688 Intake Valve Dia. Area = 5.481
Rod/Stroke Ratio = 1.796 Intake Valve Stem Area = 0.277
Bore/Stroke Ratio = 0.897 Exhaust Valve Net Area = 3.700
Int Valve/Bore Ratio = 0.724 Exhaust Valve Dia. Area = 3.978
Exh Valve/Bore Ratio = 0.617 Exhaust Valve Stem Area = 0.277
Exh/Int Valve Ratio = 0.852 Exh/Int Valve Area Ratio = 4.682
Intake Valve L/D Ratio= .356 Exhaust Valve L/D Ratio= .418
L/S/Sq.CM = 5.116 to 5.366 L/S/Sq.CM = 5.560 to 6.005
Curtain Area -to- Valve Area Convergence Intake Valve Lift MM= 6.604
Curtain Area -to- Valve Area Convergence Exhaust Valve Lift MM= 5.626


Intake Valve Margin CC's Exhaust Valve Margin CC's
1.00 CC = 0.0718 1.00 CC = 0.0990
0.50 CC = 0.0359 0.50 CC = 0.0495
0.25 CC = 0.0180 0.25 CC = 0.0247
0.10 CC = 0.0072 0.10 CC = 0.0099

------- Piston Motion Data -------
Average Piston Speed (M/S)= 20.33 in Meters per Second
Maximum Piston Speed (M/S)= 33.16 occurs at 75.451 Degrees ATDC
Piston Depth at 75.451 degree ATDC= 35.8540 MM Cylinder Volume= 149.7 CC
Maximum TDC Rod Tension GForce= 3270.08 G's
Maximum BDC Rod Compression GForce= 1845.67 G's


------- Current Camshaft Specs @ 1.270 MM -------

IntOpen= 17.00 IntClose= 43.00 ExhOpen= 43.00 ExhClose= 17.00
Intake Duration @ 1.27 = 240.00 Exhaust Duration @ 1.27 = 240.00
Intake CenterLine = 103.00 Exhaust CenterLine = 103.00
Compression Duration= 137.00 Power Duration = 137.00
OverLap Duration = 34.00 Lobe Center Angle (LCA)= 103.00
Camshaft installed Straight Up = 0.00 degrees

-Recommended Camshaft Valve Lift- MM
Minimum Normal Maximum
Intake = 7.607 8.192 9.012 MM
Exhaust = 6.789 7.313 8.044 MM
Max-effort Intake Lift = 9.442 MM
Max-effort Exhaust Lift = 8.428 MM
Minimum Intake Valve Lift to prevent Choke = 8.192 MM Lift @ 7500 RPM
Minimum Exhaust Valve Lift to prevent Choke = 7.313 MM Lift @ 7500 RPM


- Induction System Tuned Lengths MM- ( Cylinder Head Port + Manifold Runner )
1st Harmonic= 711.979 (usually this Length is never used)
2nd Harmonic= 404.096 (some Sprint Engines and Factory OEM's w/Injectors)
3rd Harmonic= 282.113 (ProStock or Comp SheetMetal Intake)
4th Harmonic= 222.047 (Single-plane Intakes , less Torque)
5th Harmonic= 180.160 (Torque is reduced, even though Tuned Length)
6th Harmonic= 151.568 (Torque is reduced, even though Tuned Length)
7th Harmonic= 130.812 (Torque is greatly reduced, even though Tuned Length)
8th Harmonic= 115.054 (Torque is greatly reduced, even though Tuned Length)
Note> 2nd and 3rd Harmonics typically create the most Peak Torque
4th Harmonic is used to package Induction System underneath Hood

Plenum Runner Minimum Recommended Entry Area = 8.176 to 9.199 Sq.CM
Plenum Runner Average Recommended Entry Area = 9.401 Sq.CM
Plenum Runner Maximum Recommended Entry Area = 9.603 to 11.364 Sq.CM

Minimum Plenum Volume CC = 237.8 [typically for Single-Plane Intakes]
Minimum Plenum Volume Liter= 0.2378 [typically for Single-Plane Intakes]
Maximum Plenum Volume CC = 1358.7 [typically for Tunnel Ram Intakes]
Maximum Plenum Volume Liter= 1.359 [typically for Tunnel Ram Intakes]


------- Operating RPM Ranges of various Components -------

Camshaft Intake Lobe RPM = 9553 Exhaust Lobe RPM = 9358
Camshaft's Intake and Exhaust Lobes operating RPM range = 7504 to 9504
Note=> Lobe RPMs are only BallPark estimations

Minimum Intake Valve Lift to prevent Choke = 8.192 MM Lift @ 7500 RPM
Minimum Exhaust Valve Lift to prevent Choke = 7.313 MM Lift @ 7500 RPM

Current (Intake Valve Curtain Area -VS- Time) Choke RPM = 8604 RPM
Current (Exhaust Valve Curtain Area -VS- Time) Choke RPM = 9639 RPM

Intake Valve Area + Curtain Area operating RPM Range = 5834 to 7834 RPM

Intake Valve Diameter RPM Range = 6604 to 8604

Intake Flow CFM @28in RPM Range = 5441 to 7441
___________________________________________________________________________

Best estimate RPM operating range from all Components = 5613 to 7613

Note=>The BEST Engine Combo will have all Component's RPM Ranges coinciding
___________________________________________________________________________




Note=> Look at the <Intake Choke RPM> column , scroll down to where the
Choke RPM matches the closest you want Peak HP RPM to occur at ,
then that Valve Lift is the MINIMUM Lift required at that Peak HP RPM


Note=> To account for Valve Lash Loss and ValveTrain deflection Lift losses
it is highly recommended that you use the Maximum recommended
Camshaft Valve Lift values , ... also the Maximum-Effort Lift values
are the highest Lift values that should be attempted.


Note=> The Cylinder Head Flow CFM column is the LEAST CFM that is required
to attain that RPM .


Also look across the <Recommended Port Cross-Sectional Area> column ,
those Intake and Exhaust areas are what's required at that RPM of Peak HP

If the <Curtain Area/Time Choke RPM> is lower than your Peak HP RPM input
and if your Cam's Intake Valve Lift is adequate, then that indicates the
Engine is being choked by these possiblities=> 1) Intake Valve OD too small
2) Cylinder Bore diameter is too small, and is limiting Intake Valve size

You cannot achieve 125 % or greater Trapped Volumetric Efficiency % if the
<Curtain Area/Time Choke RPM> is lower than your Peak HP RPM input


Due to differences in FlowBenches and Dynos, the required Intake and Exhaust
Flow CFM @28in. may be 20-30 CFM lower and 20-80 HP lower than your Dyno or
your FlowBench . CFM Flow Lag Times will often cause the required Peak CFM
Flow to occur at different Crank Angle Degrees, than what PipeMax predicts.


Note=> HorsePower and Torque data are corrected to SAE J1349-STD
29.92 in.Hg. Barometer, 60.0 deg.F, 0.0 % Humidity, 0.0 Ft Sea-Level
and correlate to a Dyno test acceleration rate of 600 RPM per Second

Exhaust:


************** Metric Units ******************


--- Tri-Y Header Design Specs --- for 1.359 Liters from 5500 to 8000 RPM

1st Y-Segment Dia. MM= 33.237 Length= 311.4 to 338.4 MM long
2nd Y-Segment Dia. MM= 36.412 Length= 311.4 to 338.4 MM long

--- Header Collector Specs (Conventional Straight Tube) ---
Diameter MM= 50.575 to 56.925 Tuned Lengths= 367.7 best and 183.9 or 735.5

H-Pipe= 367.7 X-Pipe= 1471.0 distance behind end of Primary Tube ends

-- Total Exhaust System Tuned Lengths (Primary ends to TailPipe end) --
Best HP/TQ Tuned Collector Lengths= 367.7 , 735.5 , 1471.0 , 2941.9 MM long

Worst HP/TQ Loss Collector Lengths= 551.6 , 1103.2 , 2206.5 , 4412.9 MM long

Note=> measured from where the Primary Pipes end inside the Collector to
the point the tailpipe exits into the atmosphere.

Note-> all Pipe Diameters are OD and based-off 1.588 MM Pipe thickness

---- Primary Pipe's Harmonics ----
3rd Harmonic = 622.9 MM long, both Y-Segments combined Length, best TQ + HP

---- Collector's Harmonics (includes Intermediate, Muffler , TailPipe) ----
1st Harmonic = 2941.9 MM long ... longest with Mufflers and TailPipes
2nd Harmonic = 1471.0 MM long ... longest recommended with Mufflers
3rd Harmonic = 735.5 MM long ... more bottom-end Torque
4th Harmonic = 367.7 MM long ... highly recommended , best Torque Curve
5th Harmonic = 183.9 MM long ... reduced Torque , more top-end HP sometimes
6th Harmonic = 91.9 MM long ... reduced Torque , not recommended

Edited by Sir Yun on 20th Jan, 2008.

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

Wohw, i'll need to sit back, take my time and read through this in detail :)

Excellent stuff, Thank you

http://www.efiminis.olicentral.com/index.php?topic=60.0

So an average of 136 hp?

I would try cams set at 106 ICA and 106 LCA (thus also 106 ECA)
and perhaps a higher CR of 11:1?

Somewhere on this board the K100 cam profile was posted.

Groetjes,
Richard

Is that for the LT cams. I'm interested in what the RS cams would do.

Can anyone have that prog? I'm into my physics and I'd like to see how they compare with my findings/ideas.

Bugger off, I'm getting there.

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

I think he means the Pukka RS cams

Ah "THE" rs cams..gotcha!

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

I'd certainly like to see what the longer cams would go like. As a sort of hunch, I'd say that an LT inlet and an RS exhaust would be best for a turbo.

I've got a lot of tax rebate due and I'm looking at buying a short 1380 engine to whack on my box and do a N/A RS engine. I'm going to do my own crank from an A+ and hope that I wont need to break it to get the most out of it.

Got a nice gearbox/car waiting for it

Bugger off, I'm getting there.

I cannot/will not give you the program as i find you have to buy if for yourself. it's only $35 and Larry Meaux has allways been a great help.

the exhaust sizes and lenghts for various headers ( uhm that'll be exhaust manifold in proper english) tend to be really good.

the power calculations are an free add on. and are not on par with 100k UPK apps like virtual 4stroke or 4SThead.

Edited by Sir Yun on 6th Feb, 2008.

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

Are the exhaust data in the range of what Vizard describes in the bible?

Edited by ettore bugatti on 31st Jan, 2008.

how do you mean ?
I/E ratio?

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

In the last Vizard, he published some exhaust runner lengths for eight ports for various cam duration. He als made a graph for the diameter of the primary runners.

the range is about the same.

pipemax uses
Bore size, stroke, rod lenght, CR, valve diameters, peak rpm use and cam spec to determine the diameters and lenghts

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

10 year thread revival.

Has anyone looked into the optimum intake runner length for maximum torque on sprint spec 1380, with sc's hot cams, fully ported running 38mm bmw throttle bodies?

Considering the limited range of velocity stacks and ram pipes, and the slight quirks with each engine configuration, manifold set up etc. there are learly loads of variables for each application.

Spotted a few interesting velocity stacks on the following site that offer potential. The 110mm long one looks good even if there will be a big hole in the front, or for the more subtle look a 39mm ID with decent radius.

https://www.xtremeautoparts.com.au/shop/pc/...Stacks-c367.htm

Edited by minimole23 on 17th Feb, 2018.