what is this "CLANK-CLANK-CLANK-CLANK" noise?
#21
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The noise is 100% definitely coming out of the intake valvetrain...and I'm pretty sure I have compression (enough to shoot-out the socket extension in the sparkplug well), so I'm very confused.
#24
If you're running a 99-00 head, maybe pop off the top half of the intake mani and make sure all the VICS butterlies are still in place. I haven't looked at a VICS setup closely but the Toyota TVIS is pretty similar and I've seen those lose them. Could just be sitting in the intake rattling on the valve...
#25
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If you're running a 99-00 head, maybe pop off the top half of the intake mani and make sure all the VICS butterlies are still in place. I haven't looked at a VICS setup closely but the Toyota TVIS is pretty similar and I've seen those lose them. Could just be sitting in the intake rattling on the valve...
#27
If you're running a 99-00 head, maybe pop off the top half of the intake mani and make sure all the VICS butterlies are still in place. I haven't looked at a VICS setup closely but the Toyota TVIS is pretty similar and I've seen those lose them. Could just be sitting in the intake rattling on the valve...
I just replaced an intake on a 2.0 liter Mazda 3 for that exact reason. Very loud almost knocking sound tick coming from the butterfly's. i pulled vacuum on the actuator and the noise went away. Granted the manifold and butterflys on the 3 were plastic its still worth a check.
#30
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I retorqued the cam cap, check every lifter lash and they're between .003-.006 intake/.005-.008 exhaust. Its silent again and drives fine. #4-I and #3-E need about .002 taken out of them to be absolutely perfect, but I'm back in business and ready for the track again.
Houston here I come!!!
Houston here I come!!!
#31
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I retorqued the cam cap, check every lifter lash and they're between .003-.006 intake/.005-.008 exhaust. Its silent again and drives fine. #4-I and #3-E need about .002 taken out of them to be absolutely perfect, but I'm back in business and ready for the track again.
Houston here I come!!!
Houston here I come!!!
Glad you figured its all out. I am excited to start tracking this season.
#38
I've seen the "tight" valves thing done, it gives you slightly more effective cam duration. It's a pretty small difference though, don't know I'd try it in this context. Two things I'd be concerned with running smaller valve clearances, first that the valves aren't getting to close fully when the engine is at operating temp, and second that the exhaust valve isn't on the seat long enough to cool properly. First one is easy enough to check, just warm it up, yank the valve cover and measure.
Glad you found the noise... question now is, WHY did the cap come loose?
Glad you found the noise... question now is, WHY did the cap come loose?
#39
For main and rod bearing oil clearances yes, high performance engines do tend to be looser. (I'm sure neogenesis will be able to explain the reasoning behind it far better than I)
I think the reasoning behind running tighter than normal valve clearances is to reduce the chance of ejaculating one of the shims at high rpm.
Randy mentions this on his solomiata page but he runs .008" as opposed to the factory .015" cold lash.
I think the reasoning behind running tighter than normal valve clearances is to reduce the chance of ejaculating one of the shims at high rpm.
Randy mentions this on his solomiata page but he runs .008" as opposed to the factory .015" cold lash.
#40
In a hydrodynamic pressure fed journal bearing the oil has two jobs. One is lubrication. The other is cooling. If you set the clearances a little on the loose side more oil flows through, and provides more cooling.
The fact that it's pressure fed really doesn't do that much for the lubrication part. It's the spinning journal that builds up a pool of oil that it rides on (the hydrodynamic part). There are plenty of "splash lube" engines out there, it was pretty standard up until about 1950 or so. Most every cheapie lawn mower engine still works this way. The main advantage of pressure fed bearings is that you can make them much smaller, because the cooling effect is dramatically improved. This also explains why splash lube bearings tend to be smaller in dia and longer. You get the same bearing surface area, but slower surface speeds. How fast you can reliably spin a journal bearing is heavily dependent on the ft/sec the surface is traveling at.
The fact that it's pressure fed really doesn't do that much for the lubrication part. It's the spinning journal that builds up a pool of oil that it rides on (the hydrodynamic part). There are plenty of "splash lube" engines out there, it was pretty standard up until about 1950 or so. Most every cheapie lawn mower engine still works this way. The main advantage of pressure fed bearings is that you can make them much smaller, because the cooling effect is dramatically improved. This also explains why splash lube bearings tend to be smaller in dia and longer. You get the same bearing surface area, but slower surface speeds. How fast you can reliably spin a journal bearing is heavily dependent on the ft/sec the surface is traveling at.
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