Spot on Rick! Checking everything. The bores are in spec, but they are not inline, so a line bore will be on the cards, and the crank will go to first undersize.
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Spot on Rick! Checking everything. The bores are in spec, but they are not inline, so a line bore will be on the cards, and the crank will go to first undersize.
Mittelmotor sourced and rebuilt a "New" "019" MFI pump correct for 2.7 MFI and casting date "38/72 or September 1972 and Bosch build date "321" or January 1973... Probably more correct for a 3 series RS, but at least the right "era" for a September 1973 build 1974 2.7 Carrera
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In parallel - we had the tachometer calibrated and a new face with 2.7 MFI redline, and the speedometer calibrated and repaired.
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That was some sloppy engine work, glad you are with an experienced shop now. I've seen cam wear like that when not using the proper ZDDP oil.
Once these mag blocks have gotten all the proper updates they are quite reliable. Line bore, shuffle pin time serts or case savers. Worthwhile to upgrade to a later oil pump too.
Are the CIS pistons compatible with MFI? I thought they were different.
Definitely different pistons.
Yes the Pistons & Cylinders are different for CIS and MFI... When the PO had the engine rebuilt, they pulled the CIS injection off, and went with Weber 40s, "E" cams and stock RS pistons & Cylinders at 8.5:1... The engine made good oil pressure, had good compression and leak down numbers, and ran OK, but just didn't "feel" right... hard to explain, I put it down to the carbs needing to be tuned or rebuilt, but I knew I was going to rebuild and go MFI when I was buying, so the carbs didn't really matter to me... I just didn't realise how much of the previous parts that were new replacements would be trash and not reusable...
We are doing all the "usual" work to the magnesium case to make it reliable again, except shuffle pinning, as it will be a stock, not a racing engine, we determined it wasn't really necessary for this build...
While the engine and gear box were out, we had the bottom of the car dry ice blasted, so it would be clean and we could get focused on some of the areas of the chassis that need attention... one of the POs had replaced the front pan, and whoever did it, has no business doing metal work on cars... we also found a poor patch panel where the dealer air had been installed in the "smuggler's box"... and a new spot on the left side just where the front tire had been rubbing the inner fender well... all in all, nothing too serious and relatively straight forward to put right...
Here are a couple of video links and some photos
https://youtube.com/shorts/WpNpDVcG-sk
https://youtube.com/shorts/Bu3YNrxjeh8
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The tin worm had worked that spot a bit. Nothing horrible.
Gearbox rebuild underway...
Focus is to give it a factory standard rebuild - no shorter gears this time, normal wear an tear items - bearings, synchos, etc... The only upgrade will be a ZF LSD as could have been ordered when new...
Case after cleaning, new parts, and LSD
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Nice, do you know what method was used to clean the trans case?