The forever project
#306
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Driving the Miata to my Dad's place tonight, going to pull the valve cover off to see about the noise I've been having. After seeing Aidan's issues with his lifters, I'll be checking those, gauging the lifter clearances and overall looking for unusual wear. I'll try to post pics later tonight/
#307
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Pulled the VC off and found.... NOTHING. No problems in the top end whatsoever, gaps on 4 of the valve pairs were all below .01 for gaps. I did find a thread that mentioned the grommets between the heater core hoses and the firewall can wear out, and one does move more than the other and there's a hose clamp that I COULD see tapping against the other clamp or the brass against the firewall.. I believe I'm going to replace the valve cover gasket and try driving it again, if I get the buzz I'll ziptie the hoses together to see if that resolves it. Seems to go away with heat when the engine gets hot, so I was thinking bearings buuuut.. the hoses get softer with heat too, which could make it change the vibration pitch? IDK. Will know more tonight.
#308
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Got things cleaned up, lost a fairly big rtv chunk into the oil passages. Ran a gallon of mineral spirits through the engine to clear anything out. Poured oil over the cams. Rtv applied and valve cover on, just needs to cure now.
#310
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I thought the difference in 'strength' was caused by the acceleration and deceleration bias of the respective units. I thought autocross folks preferred the T1's due to driving characteristics, but the T2's were less likely to go kablooey during a launch since they're decel biased.
#312
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Torsen Diff - Spec Miata Garage - Mazda Racers
"Type 2 is a fundamentally more robust design". Don't have an 'official' source for that, but perhaps there was confusion with the T2R unit which was a specialized version of the T2. It's also funny that torsen has a faq saying that the NA/NB torsens are no longer being made as they were last made in 2002 and all the tooling is gone lol.
#313
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You didn't finish the quote.
"The Type II is a fundamentally more robust design, but I have not heard of either unit breaking from track use. They seem to last forever."
"The Type II is a fundamentally more robust design, but I have not heard of either unit breaking from track use. They seem to last forever."
#320
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Noise still extremely prominent between 3250 and 4k, dad's thinking it might be the downpipe (crack/fracture somewhere?), he's getting a lot of noise and vibration off the turbo from the stethoscope and was thinking maybe it was that. Spool and turbo characteristics were OK as of a few days ago (well after the noise started) so I'm leaning to a downpipe crack resulting in harsh harmonics after the turbo and the plywood undertray is acting as a reflector. Is there an easy way to dump exhaust up off the manifold if I pull the turbo off to test the car? Hmmm...
I still have my TSE downpipe so perhaps I'll be giving that a go? Fighting a cold, might be a while before I get to this :(
I still have my TSE downpipe so perhaps I'll be giving that a go? Fighting a cold, might be a while before I get to this :(