The start of my 2.0 build, and also the start of my questions |
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The start of my 2.0 build, and also the start of my questions |
MrKona |
Dec 14 2007, 09:19 PM
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#1
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Senior Member Group: Members Posts: 597 Joined: 25-July 05 From: Santa Rosa, CA Member No.: 4,469 Region Association: None |
I talked about building up a 2.0 last winter, and now I'm finally going to do it. This is my first engine build, hence it'll be conservative and relatively stock. My only plan with the car is to have a nice, reliable, well constructed engine. I thought about a 2056, but I finally decided to stay with 94mm cylinders. I really don't want to have to tweak with FI or fiddle with cam selection right now. I've read that Jake's 9550 cam is excellent, but also that it produced dirty emissions. I'd like to keep this engine as clean as a type 4 can be. I'm also a little confused if Jake is even selling cams at the moment, so I've just decided to go with a stock grind.
My current engine is a PO rebuilt 1.8 with hydraulic lifters (with one that won't prime, sounds horrible, I can't wait to be done with them). Highlights: GA case Stock displacement (with new Euro spec pistons) Stock grind Webcam and with solid lifters (both new) For now, I'm going to cannibalize the rebuilt 1.8 heads from my current engine, unless I find a deal on decent rebuild 2.0 heads during the build. I would love to buy a pair of Raby heads, just can't swallow the extra two grand at the moment. L-jet fuel injection from my 1.8. (I have some issues to work out here, running really rich. No vacuum leaks that I can find. I have to check the fuel pressure - I'm thinking either AFM or pressure regulator as next areas to check). From what I've read on many threads here and other sites, the L-jet can handle up to a 2056 displacement. I'll keep this thread updated this winter as I work through this rebuild. I don't know how long a project this will be or how quickly I may get it done. Current progress: Jake Raby rebuild DVD - Check. Tom Wilson's book - Check. I've split the case and and planning on bringing the case, crank, and rods for reconditioning to Dan Hall's Machine Shop here in Portland. After reading various forums, this appears to be the Type IV specialist in this area. Brand new Euro-spec P/C set - Check! (IMG:style_emoticons/default/smile.gif) So now for my first question: Regarding the existing cylinder studs, Tom Wilson writes, "Unless you're installing case savers, don't remove the cylinder studs from the case. Doing so has no purpose, but does wear the potentially troublesome case threads, takes time, and stresses the studs" (p. 76). In the assembly section, he states "If the cylinder studs were removed for some reason, install them now. Apply Permatex 3H to their threads to stop oil leaks" (p. 120). I don't know the history of this case. I don't know if there was leakage at the head studs. Should I remove the studs, and reinstall with Permatex (after the case comes back from the machine shop, obviously) as a precaution to prevent potential leakage? Or should I just leave them be as is? Does it really put that much stress on the case to remove them, or is Wilson referring primarily to the Type I-III magnesium cases? I am leaning to toward remove and reinstall, as I strongly intend for this engine to be leak-free. Lastly, as I work through this process, I welcome and encourage comments. Please, if you see something I'm doing wrong, or have advice for me, give it to me! I can probably use it! (IMG:style_emoticons/default/rolleyes.gif) Attached image(s) |
MrKona |
May 23 2008, 06:32 PM
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#2
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Senior Member Group: Members Posts: 597 Joined: 25-July 05 From: Santa Rosa, CA Member No.: 4,469 Region Association: None |
It's been just over a month since I've posted. Unfortunately, progress was halted by a combination of school, work, and some family medical issues. It's time to get started again...
I measured deck height on all four cylinders. I actually made a torque plate so that I could torque the cylinders to spec, and then measure deck height with a dial indicator. I tried that, but ended up giving up and resorting to the method used by Competition Engineering, and also used by Wayne Dempsey in his 911 rebuild book. Deck Height Link This method relies on using large diameter acid core solder. I cut two pieces per piston, removed the acid core from each piece with a small drill bit and a paper clip. At that point, I placed two pieces on the top of each piston, a little Curil-T to hold each piece in place on the piston head. Then torqued the head to spec. At that point, it takes a half turn of the fan to bring the pistons up to the cylinder head, compressing the solder. Remove the head, take the smallest measurement of each compressed solder piece. Average the two measurements for each piston to calculate deck height. I used a .010" and a .040" cylinder to case spacer for a total of .050" on each cylinder. This gave me the following deck deck heights: Cylinder 1: .053" Cylinder 2: .052" Cylinder 3: .050" Cylinder 4: .051" Combustion Chamber volume = 57.6cc Euro spec Mahle piston dish = 3cc Stroke = 71mm Bore = 94mm Using the CR calculator on aircooled.net this gives me a calculated CR: Cylinder 1: 8.0/1 Cylinder 2: 8.0/1 Cylinder 3: 8.1/1 Cylinder 4: 8.0/1 Pretty straight forward, and I'm happy with this combo that I've achieved stock Euro-spec CR. Attached thumbnail(s) Attached image(s) |
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