NOR-CAL General Chat.

[kronus]

PC wheels doesnt make them any softer, if it did, w all the wheels that get coated people would know, its WAYYYYY more durable than paint

the baking part of PC messes up heat treatment of cast wheels, which softens them

[Pantless Spency]

from exhaust manifold to muffler for S52 swap.



I'm trying to keep my cost low and i have the down pipes and would need 2 cats to pass smog/BAR and then discovered my e30 muffler has a bit of rust. :-(



anyone know of reputable shop who can weld in the east bay that would not take my pocketbook? my down pipe needs to be modified to fit in between the manifold and subframe. i went to ask the flowmaster dealer on monument and they want $800.



I really wanna get this car on the street already. It spent almost the whole year in my garage.

Got down pipes back done in the e21 at advance muffler In Vacaville for just 450 including the cat.


The labor and materials were only 240$


The guy who runs the place (ed) is super nice and very expletienced and highly affordable for the quality of work.

Everything done in 2.5 inch.

[Pantless Spency]

Car is down at pick n pull Fairfield now. Should be available in a week or two according to them. Engine was in great shape and I had gave it a full tune up not too long ago.



Parts I have now are posted up in the norcal for sale thread.

Thanks for the heads up

[bastianshaw]

the baking part of PC messes up heat treatment of cast wheels, which softens them

Typically they are cured at around 400 degrees, not enough to effect metalurgy

http://forums.corvetteforum.com/wheels-and-tires/1988489-powdercoating-wheels-safe-or-not.html

[Cabriolet]

Typically they are cured at around 400 degrees, not enough to effect metalurgy

http://forums.corvetteforum.com/whee...fe-or-not.html

sabi old boy. i think you can only PC forged wheels, the cast aluminum ones are paint only.

[Thizzelle]

do you guys even know what you're talking about?

[Cabriolet]

do you guys even know what you're talking about?

then enlighten us

[Thizzelle]

I'm not material science but I did have to pass the class. Heat treating a aluminum in an oven over a period of time is called aged hardening. It helps with aligning your metal crystals which is a lattice of atoms or molecules (look up crystal lattice, it gets pretty crazy and material science guys say it's kind of a theory and bullshit but what ever) and relieves stress from the material and makes it stronger. From what I know if you heat treat anything, it makes it stronger but can make things more brittle. Depends on the technique, which there are a few.

[Cabriolet]

^ yes, it will make the aluminum ductile and therefore bend without breaking. but it will bend easier. i also took that class

[Thizzelle]

no it makes it stronger because all of the little imperfections get normalized and makes the aluminum stronger. That's why they age harden bike frames and I don't see them bending when hitting a bump. no way it would make it more ductile than when it was before the heat treatment process.

[BlackbirdM3]

I think it comes down to the aluminum alloy used. Bike frames are either 6061 or 7000 series aluminum (either 7001 or 7005 series). The heat treatment is different for each, and the reason you can't fix a cracked aluminum frame is that the repair can't be re heat treated without screwing up the rest of the frame leading to more cracks. How do I know? Been there and done that. I had a frame that cracked on the seat tube, it should have been an Easton Pro Gram 7005 series tubeset, however somehow a 6061 seat tube ended up in the tube set. I sent the frame back to the builder (custom built) and he welded the crack. It lasted for about 6 moths before cracking around the repair. I had a friend in college who as taking a failure analysis class so the frame got cut up and they analyzed it.

I highly doubt wheels are made from 6000 series aluminum, I'd guess something more like 2000 series. It could be that the set of wheels in question were overheated and annealed making them softer. I know plenty of people who have had aluminum bike frames powder coated with no ill effects. Again, it likely comes back to the alloy used.

Will

[Steven]

So I'm thinking Ill have my car in primer but not paint for the Berkeley marina meet and I'm in two minds whether or not to take it in that condition...? Opinions everyone?

[oliver.r]

finish it off and do it right the first time

[Thizzelle]

so i'm thinking ill have my car in primer but not paint for the berkeley marina meet and i'm in two minds whether or not to take it in that condition...? Opinions everyone?

i'd say wait and don't rush it. Who cares if it's in primer, just have to clean it up before spray.

[e30shmobberr]

the cooling method after the wheel has been heated also affects the strength of the wheel. annealing and hardening are the two processes depending on how the metal is cooled