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Stock cam stock lifters. Isky Springs. Yes I did increase plenum volume a lot. The hp curve technically never peaked. He said it did loose a very slight amount down low, but he said it was such a small amount you would never notice it in the boat.
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Originally Posted by C.I.M.
(Post 4431583)
Stock cam stock lifters. Isky Springs. Yes I did increase plenum volume a lot. The hp curve technically never peaked. He said it did loose a very slight amount down low, but he said it was such a small amount you would never notice it in the boat.
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I just found a post I made years back. I ran pipemax for intake tuning suggestions on a 502 making target max hp at 6000rpm.
Here's some info to help you with the intakes: - Induction System Tuned Lengths - ( Cylinder Head Port + Manifold Runner ) 1st Harmonic= 34.302 (usually this Length is never used) 2nd Harmonic= 19.469 (some Sprint Engines and Factory OEM's w/Injectors) 3rd Harmonic= 13.592 (ProStock or Comp SheetMetal Intake) 4th Harmonic= 10.698 (Single-plane Intakes , less Torque) 5th Harmonic= 8.680 (Torque is reduced, even though Tuned Length) 6th Harmonic= 7.302 (Torque is reduced, even though Tuned Length) 7th Harmonic= 6.302 (Torque is greatly reduced, even though Tuned Length) 8th Harmonic= 5.543 (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 = 3.197 to 3.597 Sq.Inch Plenum Runner Average Recommended Entry Area = 3.676 Sq.Inch Plenum Runner Maximum Recommended Entry Area = 3.755 to 4.443 Sq.Inch Minimum Plenum Volume CC = 1240.6 [typically for Single-Plane Intakes] Minimum Plenum Volume CID= 75.7 [typically for Single-Plane Intakes] Maximum Plenum Volume CC = 8861.2 [typically for Tunnel Ram Intakes] Maximum Plenum Volume CID= 540.7 [typically for Tunnel Ram Intakes] ================================================== ====== CSA = Cross Sectional Area 350 FPS Velocity CSA= 2.054 sq.in. at 6000 RPM Port Sonic-Choke with HP Loss 330 FPS Velocity CSA= 2.180 sq.in. at 6000 RPM Port Sonic-Choke with HP Loss 311 FPS Velocity CSA= 2.313 sq.in. at 6000 RPM Smallest Useable Port CSA 300 FPS Velocity CSA= 2.398 sq.in. at 6000 RPM Recommended Smallest Port CSA 285 FPS Velocity CSA= 2.524 sq.in. at 6000 RPM Recommended Smallest Port CSA 260 FPS Velocity CSA= 2.767 sq.in. at 6000 RPM Recommended Port CSA 250 FPS Velocity CSA= 2.877 sq.in. at 6000 RPM Recommended Port CSA 240 FPS Velocity CSA= 2.997 sq.in. at 6000 RPM Largest Intake Port Entry CSA 220 FPS Velocity CSA= 3.270 sq.in. at 6000 RPM Largest Intake Port Entry CSA 210 FPS Velocity CSA= 3.426 sq.in. at 6000 RPM Torque Loss + Reversion 200 FPS Velocity CSA= 3.597 sq.in. at 6000 RPM Torque Loss + Reversion |
That's awesome. I need to play with that. Those runner CSAs are what we should actually be looking at when everyone starts furiously debating head runner CCs.
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Thats why im planning on cutting runners out of upper plenum and in lower intake to achieve 13.5" or so to valve. Would be interesting if cim had used bigger cam and better lifters.
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Originally Posted by C.I.M.
(Post 4431502)
Yes they were apples to apples.the were the uncorrected numbers. The weather was so good the correction wasn't changing it more than a couple hp. It made 40 hp more straight off the start. Then with some tuning we ended up with the 61. And yes it kept pulling all the way to 6000. I would really like to see what it would do with a big cid motor.
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SO I have received my 500efi intakes back from having the front of the intake machined and same for the throttle body opened from a dual blade to single. I now have them installed and tested on the boat .
specs on the motors as known , 500 / 540ci short deck , flattop pistons , cam size unknown , heads are dart pro1 345 cc , 500 efi intakes . dyno sheet was 685 ( do not believe this engine is over 600hp ) after a quick retune to check air flow ratio ................. I do not notice any speed gains ! or performance changes . SO SAVE YOUR MONEY AND CHANGE THE INTAKES TO A BETTER FLOWING INTAKE |
Originally Posted by kennyd
(Post 4438643)
SO I have received my 500efi intakes back from having the front of the intake machined and same for the throttle body opened from a dual blade to single. I now have them installed and tested on the boat .
specs on the motors as known , 500 / 540ci short deck , flattop pistons , cam size unknown , heads are dart pro1 345 cc , 500 efi intakes . dyno sheet was 685 ( do not believe this engine is over 600hp ) after a quick retune to check air flow ratio ................. I do not notice any speed gains ! or performance changes . SO SAVE YOUR MONEY AND CHANGE THE INTAKES TO A BETTER FLOWING INTAKE |
I took it as he installed bigger single blade tbody and machined tbody entrance to intake manifold. Nothing else.
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Originally Posted by 33outlawsst
(Post 4438680)
Who did the work on the intake & TB, are you saying this was a waist of time & $$$
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