Turbocharged '92 BMW 525i *Updated
07-24-2007, 06:42 AM
#151
1.0 BAR
Join Date: Dec 2002
Posts: 604
Re: Turbocharged '92 BMW 525i *Updated
the soda blasting looks great man totally worth the effort. on aluminum using blast media with any kind of grit seems to actually take off the top layer of aluminum. this doesnt really matter on the outside but for the inside of the head and the chamber area id much rather use soda.
I'm still trying to convince my friend to do his. It's nice to see you're updating the motor. I'll be in touch!
08-05-2007, 07:51 PM
#153
1.0 BAR
Thread Starter
Join Date: Dec 2006
Posts: 277
Re: Turbocharged '92 BMW 525i *Updated
Thanks Steve!
I have some more updates... and they're pretty ridiculous.
Today my friend Jay and I spent all day preparing a few things for both our cars.
I brought my cylinder head which I had spent nearly 2 hrs masking off in order protect all critical surfaces from powder coat. I left a few studs in because I intend on removing them and replacing when done. Anyway here are some pictures of that.
This is the head before:
(sorry for soft pic the camera didn't want to focus on the puffy cylinder head... powder has a weird effect when not cured)
Once baked, this is what came out...
Its hard to photograph the reflections from the head, but its a very near chrome effect, looks freaaaaaaking amazing if you ask me. Here are some more close up pics...
Once that was done I was super motivated to do the block. I don't recall anyone ever doing a silver block so I was really pumped to see the out come.
So, I originally intended to just coat the block over the factory finish - well, that didn't turn out to be a good idea because Jay noticed some crap buildup in corners even after having the block hot tanked. So, that meant I needed to blast the block. Sooo, break out the high temp/high strength masking tape yet again, and prepare to bead blast the most awkward thing in the world...
Pre- blasting...
Post- blasting - the blackish/brown stuff you see is the original factory baked on paint. Most if all of the grease/oil was blasted clean off.
Fuzzy block...
And then...
So after all that it was only like 1
0p so we still had more time!!!
On to the pistons...
So, the ceramic coating was done with the exception of one piston that bubbled... talked to the manufacturer and they said that the piston might have needed to out gas or perhaps it was put in the oven before air drying, or too thick of application, etc., etc.
So, blasted the piston again with al oxide, which took the ceramic off with some time (good to know its really on there!). Re-coated the piston, let it air dry for more than ample time this round, and presto it's done.
But more importantly, Jay helped spray the Dry Film Lubricant on - basically some sort of high temperature teflon coating for the side skirts. In a vacuum this will make more horsepower but in reality it will definitely cut down on wear. It wasn't the easiest thing to apply but Jay is the skill there, I just aluminum oxide blast and mask - the first application we had an issue on one or two pistons because, we think, the acetone used to clean the surface after blasting seemed to carry some of the adhesive down from the masking tape and when sprayed with the DFL1 coating, it didn't sit properly and had runs. I blasted them over again and Jay sprayed it again, and it was good to go. Oh yeah masking on this ---- is really important if you decide to do it. I left about ooh about 3mm maybe down from the bottom ringland til where the teflon starts. This seemed to be the norm on all commercial coating process pictures I could find, but also it made it easier and more practical when masking off the wrist pin area - nothing like trying to aluminum oxide blast a 2mm sliver of area with masking tape on either side!
Anyway, we all know what the pistons looked like before but what the hell..
You can see how I masked the tops off (ceramic coated) and the wrist pin inset. I didn't want to coat the wristpin area because it would be quite hard to keep it linear.
Then, baked at 300F for 1 hr (I stayed til like 530 or 545 btw Jay, oh, and the cops did come)...
Nice and uniform!
And final picture, I swear..
There is the region I masked off. Looks really really good and uniform. To be honest I cannot really tell with my hand if its any more "slick" but I am not sure I am supposed to haha especially with it dry. The manufacturer said when oil sits on it, it's crazy slick and that it will reduce wear and drag, and thus free power and durability. We'll see - same product all the commercial places use though!
Oh I lied about the last picture, I wanted to post a picture of Jays new OBD1 valve cover - his OBD2 um... melted, so he got a cruddy OBD1, blasted it, and he tried out a nice wrinkle black which honestly looks ridiculous. I am thinking of buying a third valve cover (I now have one silver, one gold, and now I want a wrinkle black) to add contrast. Look how good it looks sitting on my cylinder head!
Ok that's the end of the updates.
I have some more updates... and they're pretty ridiculous.
Today my friend Jay and I spent all day preparing a few things for both our cars.
I brought my cylinder head which I had spent nearly 2 hrs masking off in order protect all critical surfaces from powder coat. I left a few studs in because I intend on removing them and replacing when done. Anyway here are some pictures of that.
This is the head before:
(sorry for soft pic the camera didn't want to focus on the puffy cylinder head... powder has a weird effect when not cured)
Once baked, this is what came out...
Its hard to photograph the reflections from the head, but its a very near chrome effect, looks freaaaaaaking amazing if you ask me. Here are some more close up pics...
Once that was done I was super motivated to do the block. I don't recall anyone ever doing a silver block so I was really pumped to see the out come.
So, I originally intended to just coat the block over the factory finish - well, that didn't turn out to be a good idea because Jay noticed some crap buildup in corners even after having the block hot tanked. So, that meant I needed to blast the block. Sooo, break out the high temp/high strength masking tape yet again, and prepare to bead blast the most awkward thing in the world...
Pre- blasting...
Post- blasting - the blackish/brown stuff you see is the original factory baked on paint. Most if all of the grease/oil was blasted clean off.
Fuzzy block...
And then...
So after all that it was only like 1
0p so we still had more time!!!On to the pistons...
So, the ceramic coating was done with the exception of one piston that bubbled... talked to the manufacturer and they said that the piston might have needed to out gas or perhaps it was put in the oven before air drying, or too thick of application, etc., etc.
So, blasted the piston again with al oxide, which took the ceramic off with some time (good to know its really on there!). Re-coated the piston, let it air dry for more than ample time this round, and presto it's done.
But more importantly, Jay helped spray the Dry Film Lubricant on - basically some sort of high temperature teflon coating for the side skirts. In a vacuum this will make more horsepower but in reality it will definitely cut down on wear. It wasn't the easiest thing to apply but Jay is the skill there, I just aluminum oxide blast and mask - the first application we had an issue on one or two pistons because, we think, the acetone used to clean the surface after blasting seemed to carry some of the adhesive down from the masking tape and when sprayed with the DFL1 coating, it didn't sit properly and had runs. I blasted them over again and Jay sprayed it again, and it was good to go. Oh yeah masking on this ---- is really important if you decide to do it. I left about ooh about 3mm maybe down from the bottom ringland til where the teflon starts. This seemed to be the norm on all commercial coating process pictures I could find, but also it made it easier and more practical when masking off the wrist pin area - nothing like trying to aluminum oxide blast a 2mm sliver of area with masking tape on either side!
Anyway, we all know what the pistons looked like before but what the hell..
You can see how I masked the tops off (ceramic coated) and the wrist pin inset. I didn't want to coat the wristpin area because it would be quite hard to keep it linear.
Then, baked at 300F for 1 hr (I stayed til like 530 or 545 btw Jay, oh, and the cops did come)...
Nice and uniform!
And final picture, I swear..
There is the region I masked off. Looks really really good and uniform. To be honest I cannot really tell with my hand if its any more "slick" but I am not sure I am supposed to haha especially with it dry. The manufacturer said when oil sits on it, it's crazy slick and that it will reduce wear and drag, and thus free power and durability. We'll see - same product all the commercial places use though!
Oh I lied about the last picture, I wanted to post a picture of Jays new OBD1 valve cover - his OBD2 um... melted, so he got a cruddy OBD1, blasted it, and he tried out a nice wrinkle black which honestly looks ridiculous. I am thinking of buying a third valve cover (I now have one silver, one gold, and now I want a wrinkle black) to add contrast. Look how good it looks sitting on my cylinder head!
Ok that's the end of the updates.
.
08-08-2007, 06:51 AM
#159
1.0 BAR
Thread Starter
Join Date: Dec 2006
Posts: 277
Re: Turbocharged '92 BMW 525i *Updated
Originally Posted by the 13th round
did you brace that mani at all before you strapped that big *** pipe and turbo to it? BTW car looks ------- sweet.
08-08-2007, 10:23 PM
#160
1.0 BAR
Thread Starter
Join Date: Dec 2006
Posts: 277
Re: Turbocharged '92 BMW 525i *Updated
Update - spent this evening putting the cylinder head together - sort of makes me hate having 24 valves, but then, it'll all be for the best
I used VHT assembly lube to lube the valve stems nicely. Used our custom machined dual valve spring compressor/installation tool we made, and went just as planned.
The exhaust valves don't have any texture on those discolored areas, I just coulsn't get the carbon stain/mark out with the brush wheel I used. The intake valves look brand new. The valve are all hand lapped in (sigh!) and the seat is perfect.
