3mm seals...well, I like the idea
09-07-03, 08:40 AM
#26
The thread-starter probably has more problems than simply a hot intake. Too much boost, not enough fuel (weak pump, dirty injectors), didn't cover the hole left in the IC duct, etc. I don't know what the cause was, but it would be a good idea to investigate it a little more.
Intake air temp DOES matter on turbo cars. If colder air goes into the compressor, colder air comes out. It is also less work for the turbo to provide X CFM at Y boost level and Z temperture (after the IC) if it gets cold air at the compressor inlet. I agree that a 50F drop in compressor inlet air temp won't produce the same drop in the manifold air temp, but there will be some drop in temp, and the turbo having to do less work means you will make more power as well (less backpressure).
Lots of people have used 3mm seals successfully, so they do work. But the jury is still out on how much protection against detonation-related failure (versus 2mm) they provide, if any. They are also said to not seal as well, and may chatter, too. I would consider 3mm if I was going to re-use rotors and the groove was too worn for cost reasons, but I would not use them in new rotors. If your engine builder wants to use them, however, it probably makes sense to go with his recommendation. Otherwise, you might get an "I told you so" if something does go wrong with the rebuild. That may provide an "out" for the builder in the event of a problem.
I'm having my engine rebuilt right now, and I will be using either the new Mazda 2-piece 2mm seals (though the reports so far are scaring me away from them) or I might try some ceramic 2mm seals.
-Max
Intake air temp DOES matter on turbo cars. If colder air goes into the compressor, colder air comes out. It is also less work for the turbo to provide X CFM at Y boost level and Z temperture (after the IC) if it gets cold air at the compressor inlet. I agree that a 50F drop in compressor inlet air temp won't produce the same drop in the manifold air temp, but there will be some drop in temp, and the turbo having to do less work means you will make more power as well (less backpressure).
Lots of people have used 3mm seals successfully, so they do work. But the jury is still out on how much protection against detonation-related failure (versus 2mm) they provide, if any. They are also said to not seal as well, and may chatter, too. I would consider 3mm if I was going to re-use rotors and the groove was too worn for cost reasons, but I would not use them in new rotors. If your engine builder wants to use them, however, it probably makes sense to go with his recommendation. Otherwise, you might get an "I told you so" if something does go wrong with the rebuild. That may provide an "out" for the builder in the event of a problem.
I'm having my engine rebuilt right now, and I will be using either the new Mazda 2-piece 2mm seals (though the reports so far are scaring me away from them) or I might try some ceramic 2mm seals.
-Max
09-07-03, 08:51 AM
#27
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Originally posted by xstacy7
This is what Pettit Racing told me...
With the 2mm seals they wear the slot out a little bigger. They say when you come back after doing a rebuild to put the seals in the slot...if you go back with 2mm, they tend to have a slight amount of "free space" to wiggle about in there. Well what they do is mill it out to 3mm so they are nice and tight. This is just what i got from them down there...
This is what Pettit Racing told me...
With the 2mm seals they wear the slot out a little bigger. They say when you come back after doing a rebuild to put the seals in the slot...if you go back with 2mm, they tend to have a slight amount of "free space" to wiggle about in there. Well what they do is mill it out to 3mm so they are nice and tight. This is just what i got from them down there...
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