Dodge72
Odd one out
Hey y'all. I'm posting on behalf of my boyfriend's 73 Duster that he's been having issues with every time he tries to drive it and we need some advice. Some background: He's got a 360 with flat top pistons (not sure what brand), 340 X-Heads with 2.02 intake valves and possibly more work done to them (haven't looked yet), unknown brand of headers, 2 1/2" dual exhaust, and a single-plane intake with a 750 CFM Edelbrock. Crane Cam adjustable gold rockers. I'd have to find cam specs but it's a pretty aggressive street/strip hydraulic flat tappet cam from Comp.
Edit : His cam is a Comp Xtreme Energy, # XE284H..507/.510 lift @ 240/246 @ 50
Most recently he had switched over his single plane Holley Strip Dominator for a more streetable dual-plane Edelbrock RPM (non-air gap). After the install, he heard what sounded like a misfire and using a infrared temp gauge, it read that #5 was cooler than the rest and not firing. Found that his plug wire was starting to crack from heat. Patched it up and started it again. He got it to warm up, and tried to take it out for a short drive. He got to the stop sign and hit the gas, only to get a huge cloud of white smoke from the driver's side exhaust. Trip over! Turned around and limped it home. Now what has been a standing issue is that #1 is EXTREMELY noisy. Almost like a solid lifter that doesn't have any oil. Super noisy when cold, does quiet some when warm but super obvious when he hits the gas. He has tried to adjust the screw on it some (all of them are set to 0 lash according to Comp), but it does not help. I say this because when he got it home we did a compression test, dry. Results:
Driver's Side
#1 = 105 psi
#3 = 155 psi
#5 = 110 psi
#7 = 145 psi
The passenger's side evened out, all at 125-130 psi. BTW, this side is completely silent, and does not smoke. We tried the wet compression test on #1 and it only bumped it 5 psi to 110. So he ended up taking the head off. Head gasket looked okay, no obvious signs of failure or breakage. (Using blue Fel-Pro head gaskets). Pistons looked okay, as did the valves. Exhaust gasket says that the headers leak, especially on #1. We are gonna do a little light test to see if the valves are sealing well, then take them out to look for straightness. I want to say it may be a bad hydraulic lifter not pumping up, or could it even be a bad exhaust leak causing the noise? A little far fetched but perhaps since this was previously a drag-only car, the heads had been milled and the original intake was milled too, allowing for ports to align? How does one check for that? I will do a cc check on the head as well when I have time, it should tell if it's been milled. Sorry for the essay, I just wanted to get all the info out of there and hopefully get some advice or some pointers on what to look for. Thank you!
Edit : His cam is a Comp Xtreme Energy, # XE284H..507/.510 lift @ 240/246 @ 50
Most recently he had switched over his single plane Holley Strip Dominator for a more streetable dual-plane Edelbrock RPM (non-air gap). After the install, he heard what sounded like a misfire and using a infrared temp gauge, it read that #5 was cooler than the rest and not firing. Found that his plug wire was starting to crack from heat. Patched it up and started it again. He got it to warm up, and tried to take it out for a short drive. He got to the stop sign and hit the gas, only to get a huge cloud of white smoke from the driver's side exhaust. Trip over! Turned around and limped it home. Now what has been a standing issue is that #1 is EXTREMELY noisy. Almost like a solid lifter that doesn't have any oil. Super noisy when cold, does quiet some when warm but super obvious when he hits the gas. He has tried to adjust the screw on it some (all of them are set to 0 lash according to Comp), but it does not help. I say this because when he got it home we did a compression test, dry. Results:
Driver's Side
#1 = 105 psi
#3 = 155 psi
#5 = 110 psi
#7 = 145 psi
The passenger's side evened out, all at 125-130 psi. BTW, this side is completely silent, and does not smoke. We tried the wet compression test on #1 and it only bumped it 5 psi to 110. So he ended up taking the head off. Head gasket looked okay, no obvious signs of failure or breakage. (Using blue Fel-Pro head gaskets). Pistons looked okay, as did the valves. Exhaust gasket says that the headers leak, especially on #1. We are gonna do a little light test to see if the valves are sealing well, then take them out to look for straightness. I want to say it may be a bad hydraulic lifter not pumping up, or could it even be a bad exhaust leak causing the noise? A little far fetched but perhaps since this was previously a drag-only car, the heads had been milled and the original intake was milled too, allowing for ports to align? How does one check for that? I will do a cc check on the head as well when I have time, it should tell if it's been milled. Sorry for the essay, I just wanted to get all the info out of there and hopefully get some advice or some pointers on what to look for. Thank you!
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