New exhaust Christmas in April
04-15-2017, 09:16 AM
#21
Registered
Bill at Diamond Marine (whom makes/sells these now - formerly KE and before that PFM) stated that the standard tails are 6". So, if you add this to your tailpipe length and can get at 19" long, you have hit it big. 
Note; these dimensions will be close to spot on for say high 500hp to high 600hp N/A BBC's.
Diamond Marine's Exhaust is extremely close to best dimensions listed below (again, adust your tailpipe length if yours are out to lunch) :
Note; these dimensions will be close to spot on for say high 500hp to high 600hp N/A BBC's.
Diamond Marine's Exhaust is extremely close to best dimensions listed below (again, adust your tailpipe length if yours are out to lunch) :
Originally Posted by SB
The following is from inputs I entered on a 502 with 625 or so HP.
Quoting myself from a earlier post
BTW: The program givea much, much more info than I have posted below. But it will give you a good idea on things.
Remember, the 'collector' is not just the headers collector. If risers and tails are same ID, which most re, then they too are part of the collector.
Do not let yourself end up at a worst length collector. It can/will kill performance.
Pipemax
Note-> all Pipe Diameters are OD and based-off .0625 inch Pipe thickness
502.176 CID from 3800 to 6300 RPM
--- Single Primary Pipe Specs --- Diameter= 1.899 to 2.024
Length= 33.7 to 36.7 inches long ---
--- Header Collector Specs (Conventional Straight Tube) ---
Diameter= 3.466 to 3.716 Tuned Lengths= 19.4 best and also 9.7 or 38.8
Best HP/TQ Tuned Collector Lengths= 19.4 , 38.8 , 77.6 , 155.2 inches long
Worst HP/TQ Loss Collector Lengths= 29.1 , 58.2 , 116.4 , 232.8 inches long
Note-> all Pipe Diameters are OD and based-off .0625 inch Pipe thickness
---- Primary Pipe's Harmonics ----
1st Harmonic = 149.4 inches long ... typically never used
2nd Harmonic = 56.5 inches long ... longest recommended
3rd Harmonic = 33.7 inches long ... highly recommended , best Torque Curve
4th Harmonic = 23.4 inches long ... shortest recommended
5th Harmonic = 17.5 inches long ... typically never used
6th Harmonic = 13.8 inches long ... typically never used
7th Harmonic = 11.1 inches long ... typically never used
8th Harmonic = 9.2 inches long ... typically never used
---- Collector's Harmonics (includes Intermediate, Muffler , TailPipe) ----
1st Harmonic = 155.2 inches long ... longest with Mufflers and TailPipes
Note: Worst = 116.4 inches long for HP/TQ Loss
2nd Harmonic = 77.6 inches long ... longest recommended with Mufflers
Note: Worst = 58.2 inches long for HP/TQ Loss
3rd Harmonic = 38.8 inches long ... more bottom-end Torque
Note: Worst = 29.1 inches long for HP/TQ Loss
4th Harmonic = 19.4 inches long ... highly recommended , best Torque Curve
5th Harmonic = 9.7 inches long ... reduced Torque , more top-end HP sometimes
6th Harmonic = 4.9 inches long ... reduced Torque , not recommended
The following is from inputs I entered on a 502 with 625 or so HP.
Quoting myself from a earlier post
BTW: The program givea much, much more info than I have posted below. But it will give you a good idea on things.
Remember, the 'collector' is not just the headers collector. If risers and tails are same ID, which most re, then they too are part of the collector.
Do not let yourself end up at a worst length collector. It can/will kill performance.
Pipemax
Note-> all Pipe Diameters are OD and based-off .0625 inch Pipe thickness
502.176 CID from 3800 to 6300 RPM
--- Single Primary Pipe Specs --- Diameter= 1.899 to 2.024
Length= 33.7 to 36.7 inches long ---
--- Header Collector Specs (Conventional Straight Tube) ---
Diameter= 3.466 to 3.716 Tuned Lengths= 19.4 best and also 9.7 or 38.8
Best HP/TQ Tuned Collector Lengths= 19.4 , 38.8 , 77.6 , 155.2 inches long
Worst HP/TQ Loss Collector Lengths= 29.1 , 58.2 , 116.4 , 232.8 inches long
Note-> all Pipe Diameters are OD and based-off .0625 inch Pipe thickness
---- Primary Pipe's Harmonics ----
1st Harmonic = 149.4 inches long ... typically never used
2nd Harmonic = 56.5 inches long ... longest recommended
3rd Harmonic = 33.7 inches long ... highly recommended , best Torque Curve
4th Harmonic = 23.4 inches long ... shortest recommended
5th Harmonic = 17.5 inches long ... typically never used
6th Harmonic = 13.8 inches long ... typically never used
7th Harmonic = 11.1 inches long ... typically never used
8th Harmonic = 9.2 inches long ... typically never used
---- Collector's Harmonics (includes Intermediate, Muffler , TailPipe) ----
1st Harmonic = 155.2 inches long ... longest with Mufflers and TailPipes
Note: Worst = 116.4 inches long for HP/TQ Loss
2nd Harmonic = 77.6 inches long ... longest recommended with Mufflers
Note: Worst = 58.2 inches long for HP/TQ Loss
3rd Harmonic = 38.8 inches long ... more bottom-end Torque
Note: Worst = 29.1 inches long for HP/TQ Loss
4th Harmonic = 19.4 inches long ... highly recommended , best Torque Curve
5th Harmonic = 9.7 inches long ... reduced Torque , more top-end HP sometimes
6th Harmonic = 4.9 inches long ... reduced Torque , not recommended
04-15-2017, 09:36 AM
#22
Gold Member
Gold MemberThread Starter
YEs I got them from Diamond...for the reason you stated 
04-15-2017, 09:38 AM
#23
Gold Member
Gold MemberThread Starter
04-15-2017, 10:01 AM
#24
Gold Member
Gold MemberThread Starter
[][ATTACH=CONFIG]566369[/ATTACH][QUOTE=SB;4546475]Bill at Diamond Marine (whom makes/sells these now - formerly KE and before that PFM) stated that the standard tails are 6". So, if you add this to your tailpipe length and can get at 19" long, you have hit it big.
Note; these dimensions will be close to spot on for say high 500hp to high 600hp N/A BBC's.
Diamond Marine's Exhaust is extremely close to best dimensions listed below (again, adust your tailpipe length if yours are out to lunch) :[/QUOTE
SB you sent me these numbers in a PM. One of the issues with my set up is, due to the side outlet exhaust, my tail pipes are of unequal length. the inboard pipes have to travel across the transom to get to the 6'' outlet (see pic). I did bypass the waterlift mufflers with the new motors, which was a huge help in flow. I reduced the number of 90 degree turns from 7 to 1- 90 and 1- 45. Not sure how much more I can do to equalize the two sides of the motor at this point. Thru the transom is not an option, I've measured and re-measured but the pipes would be practically underwater with not enough rise in the tailpipe to prevent swamping the motors.
Note; these dimensions will be close to spot on for say high 500hp to high 600hp N/A BBC's.
Diamond Marine's Exhaust is extremely close to best dimensions listed below (again, adust your tailpipe length if yours are out to lunch) :[/QUOTE
SB you sent me these numbers in a PM. One of the issues with my set up is, due to the side outlet exhaust, my tail pipes are of unequal length. the inboard pipes have to travel across the transom to get to the 6'' outlet (see pic). I did bypass the waterlift mufflers with the new motors, which was a huge help in flow. I reduced the number of 90 degree turns from 7 to 1- 90 and 1- 45. Not sure how much more I can do to equalize the two sides of the motor at this point. Thru the transom is not an option, I've measured and re-measured but the pipes would be practically underwater with not enough rise in the tailpipe to prevent swamping the motors.
04-15-2017, 10:13 AM
#25
Registered
So....what did you come out with for total lengths ?
where the tails bolt to the manifold/headrs to the very end where exhaust enters atmosphere ?
where the tails bolt to the manifold/headrs to the very end where exhaust enters atmosphere ?
04-15-2017, 10:23 AM
#26
Registered
04-15-2017, 11:07 AM
#27
Gold Member
Gold MemberThread Starter
Maybe next week I can sneak down to get some measurements
04-19-2017, 09:01 PM
#29
Registered
Just so people know, these where standard on the Volvo 600HP NA motors.
04-19-2017, 09:04 PM
#30
Registered
