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08-19-2007, 04:39 PM
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 from Memory, i'd have to go back and search thru Dyno Dates to be sure, but i think the 1st Dyno session was in 2003. We've always made 600 Lbs Torque since 2003 but thru those years we've made substantial gains in HP and RPM points. HP -VS- Torque  i hate to Post anything about this argument, but we've made the same 600 Peak TQ since 2003 or so, and the A/ND 's 60Ft and all the incrementals keep getting faster as we increase HP Likewise have a ridiculous amount of Dyno Data on SS/IA Chevy and the small Block Chrysler SS Engines/Classes, for 10 years or so we've likewise made basically the same amount of Peak TQ within a pound or so, yet we've again made substantial HP gains and those RaceCars keep going faster 60 Ft's along with all the incrementals. All the SS and Comp Engines i've Dyno tested always Launch above the Peak TQ RPM anyways and never see the RPM point of Peak TQ down the DragStrip. Last edited by MaxRaceSoftware; 08-19-2007 at 08:53 PM. 
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08-21-2007, 02:58 AM
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__________________
Has anything you've done made your life better? 
Last edited by rookie; 08-21-2007 at 03:03 AM.
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08-21-2007, 02:10 PM
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Larry,
If you decide to discuss some your favorite engine combinations like Rookie suggests, I do think its a great idea. I’m very interested in the SBC super stock engines like the SS/IA Chevy you mention. I know you can’t give out secrets of how you make these relatively small CI engines run 9 second ETs but an overall view would be great.
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08-23-2007, 03:53 PM
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on SS/IA and SS/I and a few more SuperStockers. These are real Data Files on actual RaceCars that some set NHRA Records. You can see the Trans + Gear Rtios + Stall RPM they used along with Tire Combination ET_Analyst is a completely FREE Simulator located here=> ETAVBWIN and the following is DYNO Data on #041x and #462 Heads in SS/IA concerning FPS problems and advantages that #462 with 162.0 CC -VS- #041x with 165.0 CC can make => too fast Velocity FPS can be a total disaster Note=>all 3 of these Heads were tried on the same Short Block with all the same pieces and Dyno Tuned for best possible HP/TQ Curve with those pieces. #041x SBC Heads = 165.0 CCs 1.940/1.500 valves these are the very Hi-Velocity Heads with too much velocity everywhere inside the Intake Port, same FlowBench numbers and the "BEST" Dyno test with them 600 RPM/SEC , i don't have the Sheets that we started at 3000 RPMs and all the rest of the Sheets , but only kept the Copies that stood out, and these are every 200 Hundred RPM increments as its too much Info to type every 100 RPMs, but it should give you enough Info ? note=> at 600 RPM/SEC you get a little Needle/Seat action showing up especially with small gas bowl chamber in Q-Jet, so look at Fuel Lbs/Hour trend as well as rate (Same Q-Jet Carb all Dyno Tests) RPM---TQ----HP----Fuel Lbs 4500-419.3-359.3--178.4 4700-438.1-392.1--171.5 4900-449.1-419.0--177.2 5100-451.0-437.9--169.8 5300-445.8-449.9--174.1 5500-443.2-464.1--188.3 5700-441.0-478.6--209.8 5900-429.6-482.6--222.1 6100-424.3-492.8--227.4 6300-413.9-496.5--214.9 6500-412.7-510.8--200.8 6700-407.6-520.0--210.3 6900-388.8-510.8--221.9 7100-363.7-491.7--236.1 7300-345.3-479.9--239.8 7500-325.1-464.3--233.4 7600-312.6-452.4--226.1 Avg=>406.5-464.9--206.0 -------------------------------------------------------------------------------- with #041x Heads back-to-back on same Short Block same basic Flow CFM Numbers, same valves, same CC's but with Port Velocity slower and more acceptable throughout the entire Intake Port RPM---TQ----HP----Fuel Lbs 4500-449.5-385.1--166.1 4700-444.2-397.5--164.5 4900-455.2-424.7--177.0 5100-456.2-443.0--158.3 5300-464.1-468.3--169.6 5500-471.1-493.3--192.9 5700-470.2-510.3--199.2 5900-468.2-526.0--199.3 6100-465.0-540.1--204.5 6300-459.8-551.5--209.7 6500-456.6-565.1--216.3 6700-442.6-564.6--223.1 6900-432.8-568.6--217.2 7100-426.6-576.7--215.3 7300-418.3-581.4--224.5 7500-401.8-573.8--238.2 7600-394.1-570.3--231.0 Avg=>445.7-514.1--200.4 ================================================== = with #462 castings 1.940/1.500 162.0 CC Ports differences just 3 CCs can make when ground out in the correct places, again FlowBench CFM between the #462 and the other 2 #041x Heads were very close and CFM numbers don't indicate the HP/TQ differences observed and Ports had different Velocity Profiles. Same ShortBlock and all pieces the same. RPM---TQ----HP----Fuel Lbs 4500-443.0-379.6--168.3 4700-441.8-395.4--159.8 4900-450.6-420.4--164.4 5100-456.9-443.7--169.8 5300-459.2-463.4--183.9 5500-465.9-487.9--190.6 5700-464.1-503.7--192.0 5900-463.0-520.1--195.2 6100-460.6-535.0--196.6 6300-454.9-545.7--206.5 6500-446.8-553.0--216.1 6700-438.0-558.8--225.1 6900-428.4-562.8--220.8 7100-422.0-570.5--223.9 7300-410.1-570.0--219.5 7500-395.3-564.5--226.4 7600-388.8-562.6--231.1 Avg=>440.6-508.1--199.4 Quote: Very well put - I have thought for some time that "Choke" is actually a misleading term here. David Vizard has called it "Power Limiting Port Area", a more accurate description, but unlikely to catch on. i just use the word "Choke" because sometimes the Engine will be Choked by an Area and sometimes by the same cross-sectional, but now has one of the walls with too much local velocity FPS and/or diverging too quickly on 1 wall in the above Dyno Test examples the one extreme hi-velocity #041x SBC Heads is using more Fuel, but if you try to lean it out, you loose even more Torque and HP...notice it makes Peak TQ and Peak HP lower and runs out quickly with rapid rising BSFC numbers as rising RPMs show Choke problem even more. the 2nd pair of #041x heads make more Peak TQ & HP and at higher points, and don't lay over top end. the #462 castings with 3 less CC's make Peak TQ at same point, but past Peak HP point start to layover more than the #041x Fuel consumption is about identical Same FlowBench CFM Numbers but different Intake Port Pitot Probe profiles/velocities note thats a 117.9 HP "LOSS" for the extreme hi-velocity Heads at 7600 yet..on a steady-state FlowBench test, "BOTH" Heads flowed almost as exact CFM as you could possibly make them be equal on both Intake + Exhaust sides. even used and swapped the same exact Valves out of both Heads for those tests same #041x castings , both same Chamber+Port volumes what i call the extreme velocity FPS #041x Heads were; every possible portion of that Intake port that could have Epoxy added to it, and that Flow CFM was not reduced at all, was epoxied up. and the rest of that Port was enlarged just enough to hold the same Port Volume CC's the Short Turn Apex speed was to the moon and so was the pushrod area...and just about every where else in the Port....the Floor had some "Ski-Jump" shape to it also...as it kept the CFM Numbers up and the velocity sky-high i guess you could call it an experiment to see how far you could "shrink" certain CSA areas of a Port and not reduce the FlowBench CFM numbers . pretty evident from Fuel Consumed Numbers -vs- Dyno HP/TQ Numbers that Intake Port could not handle that much speed FPS without Choke or Separation you can also see why just about everyone i know will Run the #041x heads over the other Legal #462 castings, those 3 more CC's can be used to "SLOW DOWN" the already too fast FPS one other thing that stood out in some of the Tests , was the very hi-velocity too fast FPS Heads that had a choke problem, often liked "more" low to mid lift flow. The engine's being fed sooner and more, so the cylinder depression is lesser until Choke occurs...and you still have good low-lift to take advantage of high velocity at end of stroke also the velocity FPS is slower in the smallest CSA areas, in the low to mid lift portions of the Flow/Cam Lift Curve...pumping losses working thru rod angle leverage in early and latter parts of stroke are going to be lesser than at Peak Piston CFM demand point where leverage is great and Choke makes more losses. a Closed Intake Valve has "ZERO Port Velocity FPS" at Max-Lift , typically the Cyl Head has its best FlowBench CFM Number or about in that vicinity...so Port Velocity FPS is highest at Peak Lift or so. as the valve starts to move towards max lift, Port FPS is increasing...also the minimum csa area FPS is starting to really increase or any too fast FPS area is also increasing in FPS (add to that max Piston CFM demand in vicinity of 70-80 deg ATDC and volume CCs increasing till BDC, + Flow Lag Times, pumping losses working thru Rod Angle leverage/velocity, etc.) FPS = (CFM * 2.4 ) / CSA if Head Flows 127 CFM at .200" Lift = 156.6 fps @ 1.948 csa if head flows 260 CFM at .700" Lift = 320.3 fps @ 1.948" CSA but in reality there will be CSA spots in Heads that will be smaller than 1.948 sqinches, so the FPS will be higher than 320.3 other CSA will be larger than 1.948 and other localized spots can have too high FPS even though your Average CSA of 1.948 says its only 320.3 fps the Port Volume is the same in both cases, the FPS changes up or down inside the Port in relation to the Lift/Flow Curve -vs- Piston CFM demand picking up the Low to Mid lift flow in the too-fast-velocity heads helped...but it still didn't run as fast down the DragStrip. the best way i've found so far is to slow the FPS to as close to reasonable speed as possible, as long as its not too slow, take the choke CSA out of the picture as much as possible. As I understand it, ports don't actually go into sonic choke at .55 Mach - but at this point (approx.) we reach the trade off where the energy required to move the air through the port becomes higher than the power increase (cylinder filling) that comes from higher velocity. ---SteveS Note=> a lot of this stuff is on Darin's CD also and SAE Papers in your College Library
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08-24-2007, 01:56 PM
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Larry,
I hope you don't mind that I post some of the information stored on your ET_Analyst Quarter Mile Simulation. This way we can learn more about some of the combinations as well as develop a better understanding of the simulator. NHRA SS/IA 1968 Camaro 3300 lbs { 1995 performance level } Q-Jet carb on Edelbrock Victor E intake manifold 3-Step header design #041x SBC cylinder heads with 1.940 / 1.500 valves 362 C.I. ----DragStrip Times---- at State Capitol Raceway , Baton Rouge,LA 60 Ft= 1.330 330 Ft= 4.058 660 Ft= 6.377 - 105.83 MPH 1000 Ft= 8.402 1320 Ft= 10.132 - 129.86 MPH Last edited by automotivebreath; 08-24-2007 at 01:58 PM.
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08-24-2007, 10:50 PM
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Hea,
If you guys could post some of this in the new engine combo thread that would be cool.Engine Combos May be a small part and then link them here if you like. Those numders are impressive. Although given the head and valve size the word impressive does not do it justice. Thanks for all the info.
__________________
Has anything you've done made your life better?
Last edited by rookie; 08-24-2007 at 11:00 PM.
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08-25-2007, 12:36 AM
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..i don't mind at all. Also on that 10.132 ET and 129.86 MPH , he let off just before the Finish Line, still fast enough to set the SS/IA ET with 10.132 Record that Day. it would have probably been 131 or so MPH instead. Last edited by MaxRaceSoftware; 08-25-2007 at 12:42 AM.
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08-26-2007, 02:59 PM
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Engine Combos
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08-26-2007, 03:25 PM
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automotivebreath,
there's a bunch of SS/IA Engine Data in the example ScreenShots + .PDF files . All of those PipeMax examples (except the Carb CFM Calculator) are that SS/IA Engine including the CR Calculator ScreenShot. PipeMax36xp2 When He set the SS/IA Record that was 556 HP and 470 TQ later on we steadily increased HP gains on the Dyno to 560's, then 570's ....at 575 HP and 465 TQ he ran high 9 second ET's but didn't reset the Record then...later we made as much as 585 HP with 470 TQ...but He sold that Car.
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