Plot twist
Later in the year, the car started consuming oil quite quickly, which led to a low oil event. After typical troubleshooting to identify that there was no issue with plumbing or the turbo itself, I begrudgingly turned my attention to the health of the engine itself. Mind you, this is under 3,000 miles from when I freshly built this engine last year.
Leakdown test: 22% leakdown on all 5 cylinders escaping into crankcase
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Tom Elmendorf, on Flickr
Crankcase vacuum test: I picked up a manometer from amazon to test this more accurately than "the glove test." Found that there is almost no vacuum, well under Volvo's documented minimum specifications for crankcase vacuum for which they recommend an engine rebuild.
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Tom Elmendorf, on Flickr
Between those two, it was clear that I had an issue with the rings sealing. I grieved for a day, then pulled the engine out to strip it down.
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
Here's what I found:
There was excessive wear on the bores, including scratches and scuffs on the piston skirts, the pattern of which appear to be consistent with the piston getting too hot (this seems to point to considerably advanced base ignition timing that I discovered and resolved earlier in the year, but the damage was done). The rod bearings were also quite worn already, likely due to the low oil event.
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
At this point it was clear the bottom end needed to be rebuilt yet again.
Due to the cylinder wall scratches, the block needed to be bored to the next oversize, so I ordered up 81.5mm pistons from Wiseco. The only pistons available from Wiseco also require 139.5mm rods (the current pistons in the block were a goofy custom order from RSI that have odd dimensions for rings, rods and bore). I replaced the main and rod bearings, so this is an entirely fresh shortblock now.
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
Finally, I had everything rebuilt and reassembled on the engine stand. On the bright side, it's quite gratifying being able to get the wiring and everything in place on the stand.
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
And with that, the engine was back in the car.
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Tom Elmendorf, on Flickr
Other improvements along the way
To stay sane, I decided to also make some incremental improvements while putting everything back together. I really do not enjoy tearing things down and rebuilding engines constantly, but quite enjoy making updates to little details here and there that continue to refine the car.
- NA cams
- Injector Dynamics id1300x2 fuel injectors
- E85 friendly fuel lines, filter and ethanol sensor
- Revised Getrag 265 adapter plate
- Tilton hydraulic release bearing change
- Transmission mounts with support cups
- Revised shifter bracket
NA cams
I actually had NA cams installed in the first head after the swap, but ended up putting turbo cams in later out of curiosity. I missed the slightly more top-end biased powerband of the NA cams, so these are going back in (thanks to Jacob for sourcing another intake cam after I destroyed one with a overly-powdercoated cam gear).
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Tom Elmendorf, on Flickr
Injector Dynamics id1300x2 fuel injectors
Pretty excited about these, basically just because they are like little jewels (but also because of legitimate injector data that ID publishes). Plenty of injector to run E85 and lots of boost.
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Tom Elmendorf, on Flickr
E85 friendly fuel lines, filter and ethanol sensor
Here's what the fuel line I had a hydraulic shop spec out looked like after 7 years of use... scary
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Tom Elmendorf, on Flickr
Fuel filter and GM ethanol sensor mounted in the factory fuel pump carrier
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Tom Elmendorf, on Flickr
New ethanol-rated fuel lines in place. I removed a lot of undercoating that became oil soaked in years past. At some point I'd like to refinish the bottom of the car, but figured I would at least start by removing the mess.
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
Revised Getrag 265 adapter plate
Didn't take any great photos, but I had another adapter plate machined. The first plate I had made didn't fit tightly enough on the bellhousing to ensure it remained perfectly centered. This time I dropped the transmission and bellhousing off with the machinist to have him verify my measurements. Ultimately he found that the lip where the bellhousing centers was .030" too loose. I was pretty thrilled, because I've always felt there is more driveline vibration than is appropriate.
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
Tilton hydraulic release bearing change
Why I needed to do this: Ever since swapping in the 5 cylinder with this tilton hydraulic release bearing, I've had light metallic scraping noise when the clutch is not depressed at least a little. That was the sound of the pressure plate fingers scraping along the surface of the release bearing.
According to a Tilton engineer, the release bearing is a constant contact design so the pressure plate fingers should be touching the bearing at all times, however, they should be spinning the bearing rather than scraping across the surface.
Upon inspecting the bearing contact surface, you can see that the pressure plate just barely contacts in the inner edge of the surface, beyond Tilton's recommendations of where contact should occur. This led me to experiment with a different piston & bearing combination to suit my oddball setup.
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
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Transmission mounts with support cups
Previously, I had been using factory transmission mounts from a BMW E46 M3. The transmission moves around a bit more than I would like, and it can be felt in the shifter. I ordered some uprated bushings made by UUC. These are a pretty neat design that are somewhat popular in BMWs. It's a softer polyurethane bushing that uses an aluminum cup to provide more stability for the bushing without requiring a harsh bushing material.
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Shifter bracket
I've never been quite happy with the shifter feel. I've done quite a bit to remove play from the shift linkage, to the point that just about all that was left was flex in the shifter bracket itself. The bracket came from jao/j9fab years ago as part of a getrag 265 swap kit for the redblock. It's nicely made, but required 1.5" of spacer to be located correct with the 5 cylinder. I've never liked this, so finally got around to working out something more appropriate. As seems to often be the answer, I turned to BMW to improve the Volvo. I decided to replace the trans-mounted shifter bracket with a BMW shifter bracket that pivots on the transmission and mounts to the tunnel with a rubber bushing.
I started with this crusty old shifter bracket from an early e28 BMW that has been sitting around since I picked up my getrag 265 8 or 9 years ago. All I had to do to adapt this was trim the rear mount and drill another hole for the rubber mount i chose.
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Tom Elmendorf, on Flickr
The old shifter bracket had bushings in it that were quite blown out, leading to play in the shifter observed in a quick test. These bushings are available, but are known to be somewhat loose, so I decided to try turning some bushings out of delrin, using the mini lathe sitting on my workbench for the first time. This seemed to work relatively well.
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Tom Elmendorf, on Flickr
After a bit of rust removal and coating in durable bedliner, this was ready to go in. You can see it next to the bracket made by jao (j9fab) that I've been using for years.
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Tom Elmendorf, on Flickr
The new shifter bracket mounts to the tunnel in the rear. I used one of the old E46 M3 transmission mounts for this, and trimmed the shifter foam to fit around it.
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Tom Elmendorf, on Flickr
Installed a new shift selector joint to minimize shifter play
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Tom Elmendorf, on Flickr
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Tom Elmendorf, on Flickr
A nasty surprise: The radiator end tank inlet had cracked, but wasn't leaking. This was a radiator from O'Reilly auto parts, so I ordered up another 92 940 NA radiator, except manufactured by Nissens this time.
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Tom Elmendorf, on Flickr
One other tiny detail: When I made this little bracket for the wastegate vacuum lines, I used a plastic clamp temporarily, intending to replace it later. It ended up staying on the car for quite a while, and ultimately melted while on the dyno for an extended period of time last year. Finally replaced the clamp with something less meltable.
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Tom Elmendorf, on Flickr
With that, the car is 99% back together after quite a few days in the garage while off for the holidays. The only thing I have yet to reinstall is the driveshaft, but I think it's time to install the truetrac diff, so I think I will pull out the rear axle housing next...
It occurs to me, now being multiple engine builds into this car, that the title "A reasonable project" is quite inaccurate... Not sure what it should be, perhaps "1980 242 GT. An unreasonable pursuit"