HIGH POWER PROPANE PLUS 2 YEARS
Posted: Thu Mar 12, 2009 4:09 pm
Please read HIGH POWER PROPANE BEFORE YOU READ THIS. Okay, the good the bad the ugly.
The BAD: 254 comp cam failed after 2000 miles. This engine was broken in on a dyno with the right oils before it was installed in my van, could not get number 1 lifter to quite down. After 2000 miles I decided to go to a 258 roller, a hair more lift and duration. Remember I am going for torque. The UGLY, I could still not get the motor to run good at idle and would not pass air care, (this is BC emission testing) It failed only at idle, when running at 40 miles an hour ran clean. When running at idle the motor would still jump from 600 rpm. to 1200 rpm. this was better but far from right. If you remember from my previous post I had always felt that there was a fly in the ointment with my vaporizer, also to note my power valve was running at 85% open, this gave us the best number on air/fuel and HP/Torque. Running less then this the air/fuel ratio was lean at 2700 rpm.
HERE IS THE UGLY: DO NOT TAKE YOUR VEHICLE TO A CERTIFIED SHOP UNLESS YOU KNOW THAT THEY KNOW WHAT THEY ARE DOING. After I left the shop went back to air care and the vehicle past, however at 40 miles an hour, to me it looked real lean, I should also mention the vehicle lost power. I went back to the shop and asked about the air care numbers, the mec^$%#@!ic said it was a little lean and to turn up the power valve a little. At this time I should have asked why the power valve, it was set on the dyno and should have been left alone but my bad my fault. Turned up the power valve 2 turns, and went to a car show 35 miles away all freeway driving 2700 rpm.On the way home oil pressure started to move around a bit and then dropped like a stone.I NEVER MADE IT HOME motor was gone. Because I did not do my own check on the shop and took someones word, all my work, $13K gone, back to square one. I found out later that the mec@#$%ic only turned back the power valve, did not work on the idle mixture from the vaporizer at all. Two lessons I have learned, I will always mark my power valve and I will never run without a wide band O2 sensor. These two things would have saved me a hugh cost and gave me piece of mind.
OKAY THE GOOD: Total rebuild plus a new crank, new vaporizer and dyno time, cost $5300. After a good warm up on gas, 3000rpm = 472.5 torque / old cam 475.7 at 3900rpm new cam = 501 torque / old cam 493.9. HP numbers new cam 3900rpm = 372/ old cam 366.8 5100rpm new cam = 430.9 / old cam = 4800 rpm 415.6. ON propane 3000rpm = 436.6 torque / old cam 435.6 at 3900rpm new cam = 454 torque 337.1 HP / old cam 452.5 torque 336 HP. New cam 5000rpm = 396.9 HP / Old cam 4800rpm 384.2 HP. Please remember this is in a very heavy 4x4 camperized van. All of the research I had done on cam choices did me proved me right. When you are working on a max torque low RPM motor there is no reason to put the extra costs up for a roller, the money can be better used elsewhere. If the quality of new flat lifter cams were not suspect (I have very strong views on why they fail when broken in right, at this time I will keep views to myself) I would rather be running one and use the extra money for partial costs of a trans upgrade or new gauges ect. This new motor made 18 in. manifold vac. old 19.5. New motor idled well at 700 rpm, it would seem the varying idle problem is gone.
I will be installing new motor in June 2009 as I am on Vacation until then. At that time I will post idle results, but from the dyno results I am very optimistic. If I have not answered any question or not clarified something feel free to contact me at thehook70@gmail.com or just post but please read HIGH POWERED PROPANE FIRST. Thanks.
Stroker
The BAD: 254 comp cam failed after 2000 miles. This engine was broken in on a dyno with the right oils before it was installed in my van, could not get number 1 lifter to quite down. After 2000 miles I decided to go to a 258 roller, a hair more lift and duration. Remember I am going for torque. The UGLY, I could still not get the motor to run good at idle and would not pass air care, (this is BC emission testing) It failed only at idle, when running at 40 miles an hour ran clean. When running at idle the motor would still jump from 600 rpm. to 1200 rpm. this was better but far from right. If you remember from my previous post I had always felt that there was a fly in the ointment with my vaporizer, also to note my power valve was running at 85% open, this gave us the best number on air/fuel and HP/Torque. Running less then this the air/fuel ratio was lean at 2700 rpm.
HERE IS THE UGLY: DO NOT TAKE YOUR VEHICLE TO A CERTIFIED SHOP UNLESS YOU KNOW THAT THEY KNOW WHAT THEY ARE DOING. After I left the shop went back to air care and the vehicle past, however at 40 miles an hour, to me it looked real lean, I should also mention the vehicle lost power. I went back to the shop and asked about the air care numbers, the mec^$%#@!ic said it was a little lean and to turn up the power valve a little. At this time I should have asked why the power valve, it was set on the dyno and should have been left alone but my bad my fault. Turned up the power valve 2 turns, and went to a car show 35 miles away all freeway driving 2700 rpm.On the way home oil pressure started to move around a bit and then dropped like a stone.I NEVER MADE IT HOME motor was gone. Because I did not do my own check on the shop and took someones word, all my work, $13K gone, back to square one. I found out later that the mec@#$%ic only turned back the power valve, did not work on the idle mixture from the vaporizer at all. Two lessons I have learned, I will always mark my power valve and I will never run without a wide band O2 sensor. These two things would have saved me a hugh cost and gave me piece of mind.
OKAY THE GOOD: Total rebuild plus a new crank, new vaporizer and dyno time, cost $5300. After a good warm up on gas, 3000rpm = 472.5 torque / old cam 475.7 at 3900rpm new cam = 501 torque / old cam 493.9. HP numbers new cam 3900rpm = 372/ old cam 366.8 5100rpm new cam = 430.9 / old cam = 4800 rpm 415.6. ON propane 3000rpm = 436.6 torque / old cam 435.6 at 3900rpm new cam = 454 torque 337.1 HP / old cam 452.5 torque 336 HP. New cam 5000rpm = 396.9 HP / Old cam 4800rpm 384.2 HP. Please remember this is in a very heavy 4x4 camperized van. All of the research I had done on cam choices did me proved me right. When you are working on a max torque low RPM motor there is no reason to put the extra costs up for a roller, the money can be better used elsewhere. If the quality of new flat lifter cams were not suspect (I have very strong views on why they fail when broken in right, at this time I will keep views to myself) I would rather be running one and use the extra money for partial costs of a trans upgrade or new gauges ect. This new motor made 18 in. manifold vac. old 19.5. New motor idled well at 700 rpm, it would seem the varying idle problem is gone.
I will be installing new motor in June 2009 as I am on Vacation until then. At that time I will post idle results, but from the dyno results I am very optimistic. If I have not answered any question or not clarified something feel free to contact me at thehook70@gmail.com or just post but please read HIGH POWERED PROPANE FIRST. Thanks.
Stroker