Corivus' 1991 740SE v8 swap

[corivus]

FYI didn't realize I was so close to page 9.... I just posted a few seconds before this one...

Oh I almost forgot... so last week I was driving home with the 740 and heard a loud metallic thunk and thought maybe I was really stupid and left one of my 1/2 drive sockets in the engine bay when cleaning up to head home. I get home and think nothing of it really, the next day getting to-go dinner for the family from a take out place I heard what I can only describe as a "TINK" on the drive home and I started pulling slightly to the right. At the time I though maybe the alignment got messed up because the potholes are pretty bad where this place was however when i got it home I parked it in the garage and got it up in the air and discovered this last night.



So here's the odd thing, that component was never touched but it just worked itself out, this time around I used some blue locktite and torqued it down to 63 ft/lbs and now am hoping it doesn't work its way out again. If it does I have another full suspension assembly thats all poly and rubber to replace everything with. As you can tell a few of the suspension components are starting to show their age.

Also my TAC module connector has always been kinda...melty... I went to the jy and found another "good" one, most of these are exposed to the AZ sun, heat and engine bay heat so they always fail like this on me after time. I got a new connector and its been working great. I think I'm going to relocate this module to under my dash so I don't have to worry about heat getting to it.



Also because I don't want to move this up some more here's some 4am shots of the 740 because my kids decided that was when they wanted to wake up for thanksgiving.

 

[corivus]

I got my temperature sensor working after realizing that I needed a hose barb adapter to go from the Volvo 5/8 at the firewall to whatever it was at the water pump. it was pretty simple after that, I made a T fitting with the appropriate sized hose barb connected the hoses and installed the temperature sensor fitting.



after that it was just running the 2 wires from the driver side firewall connector (yellow/black and yellow/white on the SAME connector). I then tidied up the wiring and then let the car heat up and verified with a scan tool.





And I now can accurately (as far as I can tell so far) read my temperatures from the Volvo gauge cluster, without needing to spend money on a reworked sensor that wasn't made for a lh 2.4 car. Also I had all these fittings from a previous plumbing project and the sensor was one I bought for redcar the week before it was totaled.



I also installed a double din deck after realizing my current Alpine is dieing. Went with a super cheap one and hated it so now waiting for a "cheap" jensen to arrive. update, apparently some of my wiring for the speakers had the coating come off and it was grounding out against the frame. I'm going to just run new 16ga wire to all the doors sometime next week. it already sounds leaps and bounds better.

 

[corivus]

delete this.... it setup a reply instead of edit

 

[corivus]

Ok, so its been a few months since I've updated this. I've done a few things since December, if you follow me on insta you likely have seen most of this. So I'm going to post a few updates but you may get them spaced out instead of all at once since I'm doing all this before the house wakes up. I converted to the LS6 intake manifold, swapped to electric power steering and relocated my alternator and extended a few wires.

With the LS6 intake manifold, I did a few test fits to make sure I wouldn't have to do any drastic changes as I wanted to drive it again in about 7 days.



Everything seemed to line up so I pulled the truck fuel rail, manifold, and throttle body. The truck TB went on the LS6 intake and I did another test fit. This time I realized that the vacuum port was hitting the steam vent port. I modified the steam vent port and made my own S bend hose and it all fit. The next problem was the LS6 fuel rail feed port, it hit my coil pack so I gently moved that till it cleared with the lines hooked up. after this I cleaned up the valley cover (it needs more cleaning) and put it all together. The pulley from the stock truck accessory bracket was now hitting the throttle body once the intake went on. So that led to me pulling the whole assembly and starting the relocation of the PS pump and the alternator. I also needed to run new lines for the corvette fuel pressure regulator which was very straight forward and used my truck injectors with hat adapter so I wouldn't have to get a tune if I wanted to regularly drive my car again. Last part of this was the PCV vacuum hose I just put some thick copper wire in the stock pipe and heated the hose up with a heat gun till I could bend it straight and ran a hose to it.

 

[corivus]

Swapping the alternator to a lower location was straight forward but I did have to drill and tap a hole on the block for the new mounting point. Not all LS blocks need that but mine did. After test fitting everything I found that the belt that ICT Billet suggested was to short and went with a K060555 Gates belt. Also the tensioner pulley needed different spacers to bring it in a bit more. I lengthened the wires for the alternator and assembled it all and its been great for over 250 miles so far.

 

[corivus]

I converted to electric power steering so I could relocate my 145amp alternator and run the ls6 intake. This wasn't super hard I got about 5 feet of braided PTFE line, some pushlock hose for the return and a bunch of an6 fittings along with a m16 to an6 banjo fitting and a m14 to an6 banjo fitting. I also relocated where the pump was from the passenger side to the driver side for space for activities (more on that in a future post) now that I no longer have my PCM and fuse box over there. It was all pretty straight forward once I moved the pump and the biggest issue I ran into was the power wire for the CANBUS controller wasn't supplying power.



I think this is everything so far that I've done, there is a lot more space in the engine bay and I'm now running the stock hood again. Which is a bonus because I now look like a stock Volvo station wagon, though I doubt I sound like one. I've mostly just been driving it and looking around at tuners once I decide what cam I'm going with. I think this last 5 months I put around 3000 miles on it as a DD. Now that its summer its getting put back into extra car status since my SUV is a bit better on the gas (Yay hybrids) so I think I may also redo my main wiring harness so it doesn't just sit on top of the intake manifold but I want to think out how best to do that.

 

[corivus]

I almost forgot one last important tidbit....THE ORIGINAL HOOD CLOSES!!! I'm still getting used to having a stock hood again after 4 years of the black hood with a hole in it. but it does look so clean with it on. I need to get my bumper repaired AGAIN after the accident a few Christmas' ago but its low on my list. At any rate thanks for reading

 

[corivus]

Ok, its been a while so its about time to post an update. Let’s start with the good, I finally got all my bits to upgrade my brake system to S60R front and rear Calipers/Pads/Rotors that said I had to modify a few things. The first was the dust shields for both the front and the rear. I did the rears first since I got the adapters from STS, it was a little sloppy but nothing I can’t clean up with my Dremel and some paint.



The difference in size between 280mm (was it 285?) and 330mm is substantial and didn’t really click till I did a photo comparison between the two. I did paint the rear calipers with the last of my color shift chameleon, not sure I’ll do the fronts with this though.

Next up were the fronts, I had to modify the dust shield, although the instructions show the dust shield being removed. Not sure if I’ll have to do that but I’d really like to keep the shield. I did have to tap the spindle for the m14x2 bolts and that worked perfectly. Just for reference the instructions say to add thread locker torque the bolts to 100ft/bs for the caliper adapter brackets. The caliper bolts are just simply torqued to 100 ft/lbs. I also cleaned up and got new hardware and will be running Koni Yellow adjustable strut inserts once I order them. All of this will go in the parts washer to clean up everything and maybe I’ll throw some rust protector and then paint it all black.

 

[corivus]

Now for the not so good, back in September I got into an accident and went through a median and high centered on a protective box for irrigation utilities on the median. I also grazed a tree which peeled my fender and bumper off. I did manage to find this shell which I’m going to use for the body parts, hoping to have a few locals who do body work give me advice on the best routes to take to graft the new pieces on.


I started drilling out spot welds first on the 740 to remove all the unrecoverable pieces. Mechanically everything works perfectly still aside from the cooling fans and the overflow nipple at the radiator needing to be welded back on. This part didn’t take to terribly long but I do get why the repair estimates were so high.



So back to the shell, I found it on FB marketplace for less than the gas to go up and get it with a truck. I ended up getting it with my hybrid and a tow dolly. That secured it was time to start drilling out the spot welds. It took me about 3 days to get to this point but I was mostly working at it about 2 ½ hours a day. On the plus side still on the same drill bit, I really though this one would get dull after the first 20 spot welds but its still holding strong after how many this is. Next step is drilling out the spot welds where the battery tray and wheel well meet and this whole thing should come off once I finish up the welds closer to the A Pillar.



I'm doing all this only when its slow at work so this will be slow going but its also giving me some extra skills to do some other builds I want to eventually try out including a rat rod which I'll likely end up flipping and using the proceeds to do a slightly spicier 6.0 swap with possibly a manual or I'll just stick to auto for ease of DD and backup/fun car.

 

[corivus]

Adding a little more to this post, since I have the shell I'm using it to test fit and fine tune everything. One of those are my corbeau seats, I got these off a friend a while back and just kept forgetting to start mocking these up mostly because i don't weld. I tried my hand at it and there is a lot of room for improvement but the welds penetrated through and this is my learning experience (that's what I tell myself). I started with just the lower to make sure I didn't warp the volvo rail with the bracket I made.



After that I put the seat back on to test out the height. Its got great clearance and the spot its in should work just fine.



In case someone is wondering, I have new seat skins coming in from corbeau in the next couple of weeks. I did snap one of the plastic surrounds when removing the fabric but it should snap back in place and I'll likely glue it back or see if I can source a new piece somewhere for it.

Also i checked clearance on my 17x10 rims using 32mm spacers with the front big brake conversion and its decent, I get 5/8" of space on the innner barrel of the rim and about 1/2" clearance at the face of the rim from the caliper. I think I should be able to go with a thinner adapter up front but I need to use the washer method to see exactly what would clear. I feel like my 25mm spacers would work but the wheel studs are too long and don't allow the wheel to seat so I'll need to work on that.

 

[corivus]

Ok, so I'm going to push another update out there and maybe a couple of questions once I'm done. First up is my progress on the seats, got all the mounts fabbed up for all 4 bolt holes on the seats to the adapters. this was my first time actually welding in over 25 years so there was def a lot of griding to hide how ugly everything looked. I have photos hidden away somewhere showing how bad the welding looked but I'll save that for people who know me in person and talk to me on a weekly basis though they already have seen the photos.

I used the 91 740 shell I picked up that happened to have damage on the exact same panel that I needed so its been my test mule to test fit everything i make. First two photos are of the Driver seat on the rails and then it in the car to show height and placement.



Here's a picture of the adapters mocked up to the Volvo seat rails and then on the Corbeau seat bottom frame.




Overall I am kinda excited to get these fully put together, I need to add a bit more padding for the top half of the seats but I'm very happy with the seat bottoms as they feel really comfortable. I might take them back apart and add a small layer of foam but I doubt it. I think I will also put the seat heaters in the top portion since that's the only reason I use em in my Toyota or any of my other cars.

 

[corivus]

Next update is my rims, they are 17x8 not 17x10 but I got a set of 5 from thelostartof and started refinishing them, I have 3 of 5 redone and 2 left to go, but all the centers are refinished minus the center caps which I want to see if I can get a volvo graphic or maybe just the bbs on one them to make them a bit more complete. These are redrilled to 5x108 but I'll still need to run spacers with my S60R front and rear brake conversion.

Started out with some curbed and clear coat burned style 5's



After seperating the barrels from the faces I started cleaning everything and prepping it for paint. Then I polished the 3 barrels without tires on them and did a test mount.



Once I was happy with the look I got everything clear coated and then got all the bolts on and torqued them to spec from BBS (22-24lb/ft) and took some beauty shots and then promptly put them in boxes and shoved them in a space in my garage they won't get messed up.



After that its just a matter of getting the tires unmounted from these, I already started with removing the faces and sanding then hitting them with a few coats of paint. The end color for the faces is white with a light dusting over blue/purple chameleon color shift. They aren't heavily coated but its enough of a coat that you see them really well in person.

 

[corivus]

Lastly I did a test fit of the new panel for my 740, it looks great and has a few differences from whats there but that doesn't matter to much for me. as I can make the missing mounts and get everything to fit just fine. The last part is just to spot weld this piece on which hopefully will work out just fine using a spot welding tool as I'm not that confident in my welding skills.

 

[reliant_turbo]

just read the entire thread as I am going to start my 6.0L swap on my 91 740 sedan sometime soon.

im going to have to clearance the tunnel more as im using a 4l80. I have a LS1 intake that i got for a reasonable price as the car intakes are getting pricy. i bought an entire 01 silverado 2500HD that was rotted out and had a broken rear driveshaft, also from rust, but runs fine.

Glad you are repairing the damage to your wagon. I was looking at one of the last intact images and was like "man that thing looks good" and then i scroll down to the accident and was like "noooo!"

Brian

 

[corivus]

Very nice, that should come together very well. was it 4x4 previously or did you find a RWD 2500? those were surprisingly hard to find out here.

 

[reliant_turbo]

no its a 4x4 2500. im going to pull the trans apart, give it a quick refresh and swap to the 2wd tailshaft and housing when i get more deep into the project. i have a few things that i need to clear off the plate before i can tear into it.

there is also this option https://www.innovativemachiningsolutions.com/transmission-adapters/transmissionadapter-4l80e though i think i like the idea of a longer shaft and yoke to spread out any side loads from the driveshaft.

Brian

 

[corivus]

oh cool, would love to see that process when you do it, I am hoping that once I'm back from this trip I can start working on my 740 again and post more progress, I have the new panel mocked up and ready to weld in I just need to move everything from the area that its getting installed into.

 

[lookforjoe]

oh cool, would love to see that process when you do it, I am hoping that once I'm back from this trip I can start working on my 740 again and post more progress, I have the new panel mocked up and ready to weld in I just need to move everything from the area that its getting installed into.

Are you putting body sealant inbetween the weld panels? Spot welder will work just fine & you won't have to worry about possible rust in the seams. I used Lord Fusor on my pickup lap joint spot weld panel joints - that way it has added strength as well as rust inhibiting

 

[corivus]

I'm still on the learning curve but yes I will be using sealant between the panels and honestly I'll probably use exactly what you reccomend. I got a spot welder so I'll be using that and using sealer on everything.

 

[corivus]

Ok I had free time at work again (Its slow) I made the best use of it (probably not) and got the engine and transmission out. Plan is to re-gasket the engine and just run it. I want to put a cam in it and get work done on the heads but its looking more and more offical that baby number 3 will be here later this year. And if I try to cram all this into one year I'll likely end up with a giant paperweight tha has a bunch of parts sitting around for "someday".
\

Couple things I noticed once I got the engine out were that both mounts were broken in about the same spot, the Right (passenger) side one on the hydro bracket and the Left (Driver) side at the bottom of the rubber mount. So I checked my parts bin and found a spare but I'm also contemplating changing out the volvo hydro mount and just making one out aluminum for the m3 mount to sit on so I have a few more options on customizing how my mounts sit. the other option is just to buy a new mount kit from either Giffins, Yoshifab or sts but thats more $$$ instead of using the scrap aluminum blocks we have in our junk pile.



I also went to test fit the engine back in the bay to check and see where I can gain some clearance back yesterday. Next week may be picking up again so I will likely not be working on this until it slows down again.