cam help: 502 with AFR 305cc heads
#111
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Have you put the new motors with the 305 AFR heads on a dyno? Results.....
Originally Posted by WAGS382
I have the dyno results from last Saturday, a little more power than I expected from a six year old HP 500 with 270 hours on it. Just did a little carb work and put in rapid fire spark plugs. The rev limiter comes in right after 5400 rpm. These numbers are in full marine dress with wet gill pipes and a short piece of pipe to simulate the exhaust tip, spinning all accesories, sea pump, alterator, circulating pump.
#112
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John,
I am still waiting for the heads, I expect to have them within a week or two. I wanted to be on the dyno by now, but it will most likely be late January or early February. I wonder how Thunderstruck is doing, he has his heads. Jeff
I am still waiting for the heads, I expect to have them within a week or two. I wanted to be on the dyno by now, but it will most likely be late January or early February. I wonder how Thunderstruck is doing, he has his heads. Jeff
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One long block is together, got it to my shed today. My procrastination with cams choices held me up a while. Should be on the dyno in two to three weeks or whenever I can get an appointment. Welding the water passsages on the intakes and other stuff delayed me also. However I used the time to paint the bilge and other things you should do with both motors out of the boat so it worked out OK. I'll set the valves and prime the oil passages this weekend. May try to start on the engine stand before the dyno if I can get it together.
Hopefully it'll make some horsepower.
Hopefully it'll make some horsepower.
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John,
I don't have the heads yet so I don't know the pushrod length. I think the valves sre +.100 but I will check on that to be sure. The spring wil be a standard size. Jeff
I don't have the heads yet so I don't know the pushrod length. I think the valves sre +.100 but I will check on that to be sure. The spring wil be a standard size. Jeff
#116
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As I promised here are the numbers from that 502. This started life as just a base 502 carb merc engine:
502cid - 100% stock short block other than min. deck cut to make flat
8.8 compression. Did not zero deck - pistons .012" down + .040" headgasket
850 Sea Demon 82P 90S
HVH 1" Super Sucker
HV/Brodix 2000 Intake
Canfield 310 heads / CNC Chamber / No Port Work
Cam - custom Hyd Roller Just under 225 at .050 I w/112LSA
2" Primary Schoenfield Headers - dyno mufflers
Will test Gill Exhaust again when done testing in this state
Belt driven Sea Water pump working - cross over - alternator working - no PS pump.
89 octane fuel - yep, Winter Blend right from the gas pump.
35 Degrees total timing - HEI external coil distributor ( yes, the computer one) with Jacobs amplifier/coil
RPM HP Torque
2100 194.3 483.8
2200 206.6 495.67
2300 217.5 498.52
2400 231.0 505.70
2500 243.9 512.60
2600 256.8 519.00
2700 269.2 523.36
2800 279.9 524.64
2900 288.2 521.78
3000 295.2 516.70
3100 302.8 513.17
3200 312.2 512.08
3300 323.2 514.40
3400 336.7 519.97
3500 351.9 527.69
3600 374.4 542.69
3700 387.9 550.14
3800 406.6 562.41
3900 424.7 572.21
4000 440.7 578.35
4100 457.4 584.13
4200 468.2 586.44
4300 480.3 586.50
4400 490.9 585.93
4500 500.4 583.75
4600 508.8 580.29
4700 515.1 576.90
4800 526.3 575.77
4900 531.4 569.77
5000 536.0 563.20
5100 540.2 556.26
5200 540.9 546.34
He has an Airgap on the way for a few more pulls. So for an upgrade in the $4700 range you can jump a base 502 better then a 100HP and 150#/ft of torque and have a mill that will run on 89 octane and be easy on parts.
Chris
502cid - 100% stock short block other than min. deck cut to make flat
8.8 compression. Did not zero deck - pistons .012" down + .040" headgasket
850 Sea Demon 82P 90S
HVH 1" Super Sucker
HV/Brodix 2000 Intake
Canfield 310 heads / CNC Chamber / No Port Work
Cam - custom Hyd Roller Just under 225 at .050 I w/112LSA
2" Primary Schoenfield Headers - dyno mufflers
Will test Gill Exhaust again when done testing in this state
Belt driven Sea Water pump working - cross over - alternator working - no PS pump.
89 octane fuel - yep, Winter Blend right from the gas pump.
35 Degrees total timing - HEI external coil distributor ( yes, the computer one) with Jacobs amplifier/coil
RPM HP Torque
2100 194.3 483.8
2200 206.6 495.67
2300 217.5 498.52
2400 231.0 505.70
2500 243.9 512.60
2600 256.8 519.00
2700 269.2 523.36
2800 279.9 524.64
2900 288.2 521.78
3000 295.2 516.70
3100 302.8 513.17
3200 312.2 512.08
3300 323.2 514.40
3400 336.7 519.97
3500 351.9 527.69
3600 374.4 542.69
3700 387.9 550.14
3800 406.6 562.41
3900 424.7 572.21
4000 440.7 578.35
4100 457.4 584.13
4200 468.2 586.44
4300 480.3 586.50
4400 490.9 585.93
4500 500.4 583.75
4600 508.8 580.29
4700 515.1 576.90
4800 526.3 575.77
4900 531.4 569.77
5000 536.0 563.20
5100 540.2 556.26
5200 540.9 546.34
He has an Airgap on the way for a few more pulls. So for an upgrade in the $4700 range you can jump a base 502 better then a 100HP and 150#/ft of torque and have a mill that will run on 89 octane and be easy on parts.
Chris
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Mike from Micheal's Racing engines called today to inform me that the first set of AFR heads showed up today for my motors. I hope to have some dyno results within a few weeks. Jeff
#119
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502 update: both sets of heads are in, I will measure for pushrods and finish up the combo soon. Jeff
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Originally Posted by WAGS382
502 update: both sets of heads are in, I will measure for pushrods and finish up the combo soon. Jeff