500EFI Intake modification/adaptation to Pro Flo EFI
04-23-2016 | 09:07 AM
#61
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Joined: Jun 2010
Posts: 196
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From: Omaha, NE, LOTO
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.
04-23-2016 | 09:12 AM
#62
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Joined: Jan 2006
Posts: 3,598
Likes: 1,168
From: taxachusetts
any pics of the intake mods?
04-23-2016 | 09:24 AM
#63
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Joined: Nov 2004
Posts: 14,100
Likes: 3,687
From: On A Dirt Floor
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
- 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
Last edited by SB; 04-23-2016 at 09:28 AM.
05-12-2016 | 05:31 PM
#66
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Joined: Jul 2013
Posts: 3
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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.
05-13-2016 | 10:00 AM
#67
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Joined: Aug 2007
Posts: 216
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From: rogers ark
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
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
05-13-2016 | 11:02 AM
#68
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Joined: May 2012
Posts: 11,428
Likes: 3,955
From: Midwest & T-Rock
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
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
