1971 142 Turbo v2.0
 

A brief timeline to date

• 2002-ish: purchase the car, installed iPd bars, lowering springs, rebuild the brake system, put in some race seats, and drove it all over the west coast. The B20E was a huge amount of fun running 91 octane cut 50/50 with toluene.
• 2004-ish: buy a 1989 740T and begin to (naively) pull all the parts off that for an OHC-turbo conversion.
• 2008: after a few fits and starts more or less get it running. Has some issues but it’s kind of fun. I discovered I’d built a not particularly trustworthy vehicle.
• 2010: move to a house with a garage and bring it along with me.
• 2012: take various things apart but mostly ignore it.
• 2014-2019: Slow progress that continues to result in a non-running car: upgrade the fuel system to be all AN fittings, replace all the bushing with poly, take a lot of the front end apart.
• 2020: where we are now - project v2.0

High level goals

The general theme of the project is to improve the packaging, fix some obvious screwups, and decide after 12-ish years of languishing if I’ve built a car I want, if I haven’t how to fix that, and if that’s not fixable what to do next. Perhaps tellingly, I drove the original OHV version 1000s of miles and then put about 500 miles on it in the last 12yrs.

• completely rethought alternator mount.
  In the original I added an idler wheel as the tensioning element. This was over on the drivers side of the motor and reduced the belt overlap at the crank and the water pump. It consistently squeaked even after tightening it close to yield.
• pushed radiator forward
  With the radiator in the original location and with the longer snout of the water pump there was no space to run an electric fan and the mechanical fan came within 1/8” of the radiator and 1/4” of the alternator belt.
• flipped intercooler
  Bottom inlet and outlet worked well but the air filter ended up over by the right hinge spring directly above the downpipe. Would like to eliminate hot-air-injection.
• turbo upgrade
  It’s always fun to buy new parts and I managed to score a 90+ manifold and a flat flange 18t. Rotate the turbo and swap out the manifold. It’s also nice to have an integrate CBV and the opportunity for water-cooling the center section.
• eliminate oil filter/cooler line disaster
  In the original the oil cooler pancake stayed on the block and lines ran to a remote oil filter and oil cooler. These were a disjointed mess that I always worried would foul the waste gate actuator as it came under the turbo.
• fix weeping brake block
  This is probably non-negotiable as it’s on the high pressure side. Will need to learn how to flare things as I've already determined it's not something fixable through more tightening.

“While I’m in there” and other nice-to-haves

• Upgraded brakes. The solid fronts were a little marginal with the B20 (on Highway 1) and not at all adequate with the B230
• Improved throttle pedal placement. v1.0 felt too far forward and too high.
• Return of the IAC. This got dropped for space and expedience in round one. Holding the throttle a little open when it’s dead cold is’t that big of a deal
• Complete re-alignment of the drivetrain as I have some curious vibrations.

In broad strokes, I’ve found myself completely reworking everything from the bare block out minus the relocated brake booster. A bit more of a restart than anyone might want, but, it is great to be able to try new paths.

As a project overall it’s meant to just be a fun weekend car. It still has the M41 (I do have a spare…) and a block with the early narrow rods so it’s not going to be anything radical power wise. From the time it was running with either engine it was pretty fun.

First order of business was to flip the intercooler and push all the coolers (oil, charge air, coolant) as far forward as possible to make room in the engine bay. This is with it all stacked in there on their own purpose built brackets. The oil cooler is as far forward and left as is allowable by the grill and headlamp bracket, the intercooler is spaced about 1/4" back, and the radiator is 1/4" back from that. Each is affixed top and bottom with rubber isolators so nothing should come into contact.

https://i.imgur.com/PlV03Dq.jpg?3

The oil cooler used to reside, centered, in the chin but that space is now taken up by the intercooler. The radiator back face is about where the original radiator front face used to fall. The hood is quickly closing off that space and the radiator cap clears by about a fingers width. The radiator itself is hooked up with 4x hoses from Pegasus and features a tapped block in the lower hose to hold a sensor to trigger the fan.

https://i.imgur.com/EMAprpX.jpg?3

To the right of the picture you can see the output of the intercooler. The sheetmetal bulkhead is 40* from the centerline so a 45* coupler exits that perpendicular to the wall and a conventional holesaw can make the space versus trying to create an ellipse for the tube to pass through. Behind the oil filter (at best in a prospective location) is an ellipse. This will be re-purposed to send the oil cooler lines through and will be mostly filled in once the locations of those are known more precisely.

Looking straight down its about 2" between the back of the fan and the water pump pulley and about 4" to the back face of the radiator.

https://i.imgur.com/MStP12f.jpg?1

Depending on how problematic the cooling is that extra 2" can become shroud volume. I can get a bit more space by continuing to move the fan to the upper right.

Nice car, cool project!

Glad you made a project thread for this. I love seeing other turbo 142s.

Looks good. Keep up the progress.

Great read. Love reading projects where the owner and their Volvo have so much history. Would love to see more pictures of the car and engine bay when you can. Looks great!

https://i.imgur.com/G9uB7px.jpg?1

https://i.imgur.com/9OIGz5c.jpg?1

Hoses leave the adapter, go between the engine mount and the back of the alternator, pick up 2 p-clamps built into the alternator bracket, curve below the belts and above the sway bar, miss the idler arm (at full left lock!), bend up, miss the radiator corner, and arc over the radiator hose into the oil filter and thermostat housing. It would have had just a tiny bit more space if I could have gotten another 40* clockwise on the spin on adapter. It's metal to metal now and I was unwilling to skim some off the face (in case I went too deep) or buy 10 from Amazon, find the perfectly clocked one, and return the rest.

The housing is a combined unit from Amazon (link) that I give about a 40% chance of leaking. When it arrived to me the ORB ports didn't have any kind of lead in beyond a tiny bit of thread relief. After a little aligning I cut those 4 and put some extra chamfer on that for the o-ring to land into. The sealing on the plates to hold the thermostat cartridge are also a little suspect. The pressure isn't immense, so I'll give this a whirl. Worst case scenario I throw in for the Improved Racing version this is a knock off of. Or maybe I buy 5 more off Amazon and put together the best version... I could (maybe) compromise and run a relocation plate and a thermostat pancake but I really don't want to expend that height and volume at this stage. It's tight enough all ready.

Next up is a bit more work on the alternator bracket. It's pretty far forward of the bolt holes and needs a small triangular brace to stiffen it up along with final welding. It's just tacked up right now. Blue tape still on the hose to remind myself those still need a final clean out.

I should see if I can find a picture of the old version. Now that was a mess.

https://i.imgur.com/JLKVNVz.jpg?1

Housing getting machined. The cutter is 60* which is certainly wrong for that fitting, but, then again, it's not that much pressure and the o-ring is still getting mashed into a triangle. The anodization is tragically thin.

Can we see photos of the alternator bracket?

Absolutely - it'll need to come on and off any number of times still. I got everything to fit and then retired with a bourbon. The rest of everything else (charge piping, waste gate bracket) looms so much less in my mind.

A bit more progress on the intake side of the engine.

https://i.imgur.com/PLTwH0f.jpg?1

The bracket that holds the air filter and AMM need a little triangulation and shaping but it's coming along. After all the custom tubes and stuff are done the wiring needs a serious clean. Why did I put the power stage there and the coil on the drivers side?!? Also, looks like that mandrel bend isn't quite so constant diameter.

https://i.imgur.com/vLovyUr.jpg?1

Wouldn't be the 142 project unless the clearance was tight. The intake just misses the oil filter and ducks underneath the charge pipe. I think I have about 1/2" between everything. Holding the filter was a bit of a puzzle. In any orientation where I could use the original bolts on the AMM I couldn't plug it in or it would occupy the same space as the charge pipe. The connector between the turbo and AMM will eventually feature the PCV connection.

Ah yes. Subbed.

+1 for alternator bracket photos

Still in a tubing frame of mind, I took some time for the cold side piping.

https://i.imgur.com/IYeq7jj.jpg?1

The coupler off the intercooler comes out at a 45* angle so the 135* bend picks that up and extends it around and down below the master cylinder. The 90* coupler sends it nicely between the block and the steering box and then up into the throttle body.

https://i.imgur.com/XUKhRj4.jpg?1

This pipe may pick up a little tab to tie it to the block so it gets (safely) closer to that side and away from the steering box.

This is actually a great improvement from v1.0. In that round there was an idler pulley just in the zone where the pipe is now that, feebly, tensioned the alternator belt. That forced the charge pipe to leave the throttle body, descend almost to the engine mount, make a ~120-150* degree bend to come out up above the steering box, and then descend under the master cylinder to pick up the intercooler outlet at the bottom of the cowl. A tortured path of crooked tubing spliced together with an infinite number of couplers.

I hope to come back to the bracket in the next day or so. The turbo and manifold need to come off to come up with some kind of wastegate actuator solution now that I've settled on clocking. That should better expose the alternator bracket for a quick write-up and some final work: brace on a cantilevered piece, a captured nut because I lost access to the back with the addition of the oil lines, final welding and chamfering.

can not wait!!:-D

Figured out a scheme that holds the waste gate actuator, doesn't interfere with the fender well, and puts the inlet in a spot where a hose can actually be attached. If I could weld aluminum this would be bit less unique. Trying out the actuator with a bike pump and it worked like a champ - smooth with no flex. My welding is getting slowly better, but, certainly more practice is in order before tackling all the intercooler tubing.

https://i.imgur.com/hcalSec.jpg?1

https://i.imgur.com/CkZmi1X.jpg?1

Of course the drain AN fitting doesn't fit. I'll need to grind a little bit off the compressor housing to actually get the fitting to bottom out on the outlet. Not the end of the world but another thing to remember before it all goes together for finals.

Getting closer to that alternator bracket...just so much stuff going on in that corner of the car.

Nice work with the WGA bracket.

FWIW...one of these type of oil drain connections may gain you some clearance.
https://www.ebay.com/itm/Turbo-Oil-D...oAAOxyQ45RBKLi

The straight fitting points right at the frame rail so it needs to be a 45* for sure. I like the one in the link, but, in my experience if I don't have the ability to have free rotation I'll regret it.

What's one more 45* angle AN fitting in this project? I think I'm up to at least 5.

Any chance you could share some more pictures of the whole engine bay? Curious to see how things are set up overall.

https://i.imgur.com/X2mxWgm.jpg?1

Thanks for the idea. I've not seen it this together for a long long time. My friend Rob once commented: "it's like you have an engine cover, but, the cover is engine."

https://i.imgur.com/Yn3Towu.jpg?1
https://i.imgur.com/9tX3JDB.jpg?1

Version A
This mount was in use for ~500mi and was a continual belt squealing irritation only slightly mitigated by the diagonal brace. This allowed the alternator to be pushed right up against the block on the passenger side and moved the adjustability to the idler wheel. The challenge with my implementing was insufficient belt coverage. I had the idler as tight as possible to the distributor and it still resulted in little coverage on the water pump and crankshaft pulley. To try and stop the slipping the idler was tightened within an inch of its life. Also, no provision for dual belts.

Version B
Great hopes for this because it missed more of the steering idler so more potential adjustability. This was quickly dashed by turning the steering to left lock where it interfered with the steering linkage. From the lower picture you can see the additional angle on the plate attached to the lower block bosses and how much lower the pivot point is. It places the diameter of the alternator right between the steering idler attachments and missed the cast iron bulge for the oil pressure switch/sensor. The sensor itself is out of the way but the bulge seems to limit how close it can swing into the block.

Version C
The go-forward version. At full slack it's just barely possible to get the belts on a loosened water pump pulley and at full tight one of the alternator cage bosses comes quite close (0.25") to the idler bolts. That may need to get taken off with the carbide die. With both belts attached none of the pulleys can be individually rotated and it feels very secure. With the selected alternator the mounting points are pretty far off the front of the block hence a lot of the triangulation.

https://i.imgur.com/TAKNmFp.jpg?1
https://i.imgur.com/OG7WwGC.jpg?1
https://i.imgur.com/2XWtyoq.jpg?1

Version C in some more detail. It's made up of:

• Alternator: East Coast Electric Super Mini
• Bracket (pre-massage): Trans-Dapt 8990 Low Mount Alternator Brackets
• Pulley: Powermaster V-Belt Alternator Pulleys 113
• Belt: Continental Elite V-belts 20033473

and various chunks of metal. The nut for the lower mount will need to be captured as it is inaccessible once the oil lines go in.

https://i.imgur.com/zT7dFrS.jpg?1

These two threadings accept cap headed screws that hold down a pair of p-clamps that guide the -6 hoses from the oil filter adapter to the thermostat block. The hose closer to the centerline sits on a 3/4" spacer because they need to nest horizontally to miss the sway bar and I have just a little space vertically in that area.

https://i.imgur.com/3m9JpSv.jpg?2

Part of the fun of a long project is fixing things you did a long time ago (8 yrs?!?) and in the case of the fuel pump cradle before it even had a chance to start. Me in 2012: what are these magical things called rivnuts?? That's a classic Walbro I think I installed in '06-ish?

Tfrasca - does this rhyme with your fuel system? Thoughts, comments, problems?