Quote:
Originally Posted by hassmaschine
Last time I compared part numbers, N55 exhaust rollers are identical to the N52 (I could be remembering wrong, but I'm pretty sure most of the valvetronic parts are the same, except for the eccentric shaft/drive motor). The only engine I could find any differences in was the S55, and even that is mostly the same. I wanted to order a couple rocker arms to see what the differences are - I'm betting it's mostly changes in strength/weight than geometry though.
Yeah, I've been working on prototype parts with my 3D printer. It stalled for a while during Christmas, and then I accidentally bricked the printer's CPU.. got that working again, I want to pick up some cheap material to waste on prototypes because there are a lot of problems to solve.
Mostly, it's the alignment of all the bolts that's a total bitch, and trying to clear the oil filter housing. I've got the fitment of the ports/taper etc. done but now I have to make something that fits (and decide if I want to use high temperature 3D printing materials, or pay to get it machined out of aluminum).
Edit: ah, it was the N55/S55 that shared the exhaust roller. Regardless, I did want to order one and see what the difference was. Did somebody already do that? The N52 shares exhaust rollers with the N54 though, and the N52/N55 share the intake. S55 also has a different intermediate roller, but the main roller is the same as N52/N55.
|
There’s a thread on ***********s (EDIT: a forum for people who are “addicts of boost” lol) with a bunch of info which I don’t think I can link, but that I am quoting this from:
“While I agree that the N52 and N54 rocker ratio is 1.66, I measured the N55 cam and deduced the rocker ratio to be 1.72. The part numbers also suggest that the N55 uses different rockers (rollers). N52 and N54 vehicles use the same rollers but the N55 part number is different. Why am I talking about roller ratio? Because this ratio directly impacts the amount of valve lift produce by the cam.”
“ While each engine produces very similar exhaust profiles in their respective engine, the finding pertaining to the N55 rocker ratio suggests that, by swapping an N52 exhaust cam into an N55, the resulting valve lift will indeed be higher. The number crunching can be seen in the screenshot of my quick Excel spreadsheet posted above. I found that this mod would result in about 10mm of lift which is .3mm more than stock.”
I’ve been asking around and haven’t found anyone who has tried the parts or even actually measured a set in hand. There may be someone out there who has and I would love for them to pipe in lol