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500whp LS3 swap build!

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Old 09-01-2023 | 08:29 AM
  #46  
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Re: 500whp LS3 swap build!

Got the top portion of the SSRA installed last night (bottom portion has to wait until I put the bumper back on). It was a VERY tight fit, but I got it in there! I actually had to use a block of wood and a bar clamp to pull the lower airbox forward enough to bolt it down. I'm not super happy about the amount of shear strain on those bolts, nor the constant clamping pressure being applied from the upper support through the SSRA to the condenser (basically undermining any isolation between the chassis and the condenser), but I'll go with it for now at least. If I'm not happy with the AC performance, I'll cut an opening on the backside of the SSRA like I described above to make some more room in there and give the AC some additional airflow.

All of the instructions and write-ups I could find about cutting the hole in the lower airbox suggested using a Dremel or an air saw. I used my Makita
oscillating multitool oscillating multitool
, and it couldn't have been easier! Took about 90 seconds and made hardly any mess. Everyone who does any kind of DIY stuff should own one of these.

The SSRA included a rubber seal for the hole in the front of the airbox, and the instructions said it was optional; you can choose to install the seal and maximize the ram air effect, or leave it off to allow additional airflow (although I suspect that leaving it off would actually allow some of the air brought in by the SSRA to go out through the front). The factory ram air setups on SS and WS6 apparently feed through there (I've never been up close and personal with one to see this for myself), so for them it makes more sense to leave it open. Since I don't have a ram air car, and based on my suspicion about how it would behave unsealed, I opted to install the seal. Once I have the car running, I plan to experiment a bit with it installed and not, watching what it does to my AFRs. I don't expect it will make much difference.

I also made a bit more progress bolting up the driver side front suspension.







Old 09-05-2023 | 01:32 PM
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Re: 500whp LS3 swap build!

Super productive weekend!

Saturday

I started by finishing the front suspension on the drivers side, then moving over to the passenger side and finishing up there as well. I got the shock tower brace and the Strano master cylinder brace installed. All that’s left of the front end is to install the swaybar and bleed the brakes!

In the evening, I finally got the axle shafts done! My father-in-law Doug has a friend Brad, and Brad has a home shop where he builds drag cars and show cars. Brad and his assistant Mike took great care of me. They have both dealt with this process multiple times before and were well aware that this job is a lot more complicated than the six simple press operations I had initially expected. Note that this process is specific to axles with C-clip eliminators and 4-channel ABS (traction control); I’m not sure how broadly applicable it is beyond that.

First, Mike cut off the bearing and the retaining ring with a cutoff wheel. This is necessary because the retaining ring is an extremely tight fit with extremely hard steel, and if you just press it off, the ring almost always shatters, throwing shrapnel everywhere. I had been told this in advance, so I came prepared with a pair of new SKF bearings and retaining rings.



Once those were off, it was time to install the reluctor wheel. Doug held the ring up with a long wire while I heated it for a few minutes with a MAPP gas torch. I’d estimate we heated them to 400°F. I wish we had had an IR temp gun handy! Once heated, Doug quickly dropped it onto the axle, and Mike seated it with a few soft taps with a hammer. A bit more heat would have been better; ideally the ring will drop all the way into place with no hammering. Then we repeated the process with the other axle shaft. We tried to use more heat, but without any way to measure, we ended up pretty much the same, and still needed to hammer it home.

After the reluctor, you slide the backing plate and dust shield on. It’s easiest if you begin with the parking brake shoes removed from the backing plate. Next comes the bearing, which is the only simple press operation here. A proper bearing press plate adjusted to fit closely around the axle is strongly recommended. Mike pressed the bearings on relatively easily.

After that, it was time for the retaining rings, and this is the hardest part. Doug and I started by heating the first ring with the MAPP torch, continuing until the steel lost its shiny surface finish and developed a bluish hue. Once heated, Doug dropped it on, but it didn’t slide all the way into place, even after several fairly aggressive hammer hits. So we quickly moved over to the press before the ring cooled and locked into place. With thirty tons of hydraulic pressure, Mike pressed the ring into position one millimeter at a time, with each tiny jump accompanied by a loud bang. About halfway on, one of the jumps went maybe 3mm and made a much louder bang; at first we thought we had cracked the ring. Luckily, upon inspection we found that it was fine, and Mike quickly went back to pressing it into place. After a few minutes, it was on.

On to the second retaining ring, we decided we needed more heat, and it was pretty apparent that the MAPP torch was not going to do the trick the way we wanted. So, Brad got out the oxy-acetylene torch, and heated the second retaining until it was glowing red-hot (about 900°F). I grabbed the blazing hot ring with a pair of channel locks, and dropped it onto the axle, where it slid all the way into position with no further encouragement. But now there’s a nine-hundred-degree heat source literally touching the rubber seal of the bearing, so we started spritzing it with water in order to cool it rapidly and carry heat away from the seal while avoiding quenching it too quickly and embrittling the ring.

Anyway, that was that. We hung around for a bit while things cooled, checked out Brad's latest show car build (a better-than-factory-original 1971 Buick Skylark GS 455 Stage 1, which we all think will win best in show at next week's AutoFest in Frankenmuth), and then climbed in the truck and drove home.

Sunday

With the axle on my transmission jack, I rolled it under the car. I swung the rear LCAs into place and bolted those in, then the panhard bar. Then I got the torque arm into place (that was hard!), and bolted it in. Unlike the factory ten-bolt, the Moser 12-bolt uses four shorter bolts — two on top and two on the bottom. Using a rubber mallet, I encouraged the torque arm into just the right spot to align all four holes, then bolted things down. With the axle fully located, I installed the new driveshaft, which along with my Kooks longtubes is one of the finest bits of man-jewelry I’ve ever seen.




Monday

I installed the axle shafts into the axle tubes, bolted down the retainer plates, and installed the speed sensors and parking brake shoes. I started to install the front swaybar, then discovered that I had a part which I didn’t know where to put, so that went on hold while I waited for answers. As of this morning, I believe I have things figured out!

What's next?
Install front and rear swaybars. I have new shackle bolts coming for both, but I have what I need to put things in place for now. I'll swap the bolts when they arrive. New bolts provide confidence that I can thrash on the car and not worry that the suspension is going to come apart!
Install rear shocks and springs.
Install rear brakes.
Set pinion angle.
Build/install the actual door for my fuel pump trapdoor. I'll use weatherstripping and faux Dynamat to keep things quiet back there.
Put the interior back together.
Reinstall front bumper and hood.
Add and bleed all fluids.
Start and drive it; start tuning!
Get it aligned.
Get it detailed. (After sitting for six years, it's truly filthy.)

I'm putting off some upgrades and additions in order to get the car on the road, aligned, and tuned before Winter. Hopefully I can get through this list before Spring:
1. SKF X-tracker front hubs
2. Brake cooling ducts
3. Oil cooler
4. UMI adjustable panhard bar and DS loop (I'd do these now, but I'm still waiting on the parts)
5. Finish stripping the rust off the axle and paint it.
6. Completely new stereo -- speakers, amp, and head unit. My factory Monsoon speakers are all blown! I'm stepping up to a double-DIN CarPlay-capable unit and some decent components throughout the rest of the system. I'm not a huge bass nut or anything; it'll be a robust setup focused on sound quality, with enough power to be heard over the exhaust when cruising.
7. New front seats -- going for something with more lateral support and five-point harness compatibility.

Last edited by JakeRobb; 09-05-2023 at 01:34 PM.
Old 09-18-2023 | 10:26 AM
  #48  
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Re: 500whp LS3 swap build!

I took last week off of work, so I wasn't at my computer much, but I made a decent bit of progress on the car! (and helped a friend move, and slept in, and had some quality time with my wife and kids....)
  • Installed rear brakes and connected parking brake cables, using custom cable guides I formed from some thin aluminum bar stock, as the factory guides were not playing nice with the 12-bolt.
  • Installed rear shocks and springs.
  • Worked on installing the door for the fuel pump access. I got hung up for a bit waiting on parts and tools, but everything is here now and I can continue making progress.
  • Installed Strano SP4000 hub adapters and SKF X-tracker front hubs.
  • Removed the factory panhard brace and my old BMR panhard bar; installed UMI panhard brace and on-car-adjustable panhard bar.
  • Installed UMI DS loop. Had to adjust the exhaust a bit so they don't interfere. It's still super close, and I may need to revisit. We'll see just how stiff the poly engine and trans mounts are. Maybe they're stiff enough and the exhaust and the DS loop won't rattle against each other!
  • Discovered that bolt-in LCA relocation brackets are not compatible with my 12-bolt; I have to use weld-in. Got lucky; UMI hadn't shipped them yet. Got them to change my order to the weld-in variety. Those are here, but not yet installed. I need to get the car aligned without them, then add them in so that I don't mess up the geometry.
  • Took the front suspension partially apart again, because I discovered that the rubber isolator parts were in really awful shape on both sides. I ordered new upper shock mounts; those came and are now installed. I also wanted new upper isolators, which are typically only available as part of the upper control arm bracket. I was able to find one replacement available (not counting used ones in mediocre condition). I decided to order UMI's replacement upper brackets, and those will be here today.
  • Installed the front and rear swaybars. Front endlinks are temporarily disconnected while I work on the upper control arm brackets.
Old 09-18-2023 | 10:57 AM
  #49  
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Re: 500whp LS3 swap build!

This is turning into a high tech tour de force. Great info !

Keep an eye on the Moser short torque arm bolts. They have a reputation for loosening up..
Old 09-21-2023 | 11:12 PM
  #50  
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Re: 500whp LS3 swap build!

Originally Posted by Injuneer
Keep an eye on the Moser short torque arm bolts. They have a reputation for loosening up..
So I’m told! I installed with lock washers (from UMI’s Moser torque arm hardware kit) and some red loctite; hopefully it won’t be an issue.

Old 09-21-2023 | 11:26 PM
  #51  
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Re: 500whp LS3 swap build!

Latest update:
  • One thing I was waiting for on the fuel pump door was a Cleco kit. The door is designed to be installed with rivets, and Clecos make it soooo much easier! I have just a bit of assembly put together with them, but got pulled away after just a few minutes.
  • I now have everything I need to put the front suspension back together, and I’ve been working on that. I have new upper control arm brackets from UMI to replace my rusted ones, and to eliminate the small rubber isolators which sit on top of the factory brackets.
  • I also bought new front shock mounts. Separating the old one from the driver side assembly was easy, but the passenger side was a battle against rust. My solution involved soaking in PB Blaster for several hours, then attacking it with an air hammer, and finally chasing the threads with a thread die.
  • I nearly have the passenger side suspension back together. Just need to get the shock mount lined up so the bolts will slide into their holes, while battling interference between the bottom of the shock and the lower control arm. Then I get to repeat that battle on the other side! I’m thinking I might bail on the battle entirely by just unbolting the control arm. Pretty sure it would save some time!
  • I’ve been a bit under the weather this week, so less progress than I would have liked. I worked on the car last Friday, then not again until yesterday.
  • Once the front suspension is done, I’m back on the fuel pump door.
Old 11-06-2023 | 12:20 PM
  #52  
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Re: 500whp LS3 swap build!

I caught COVID a few weeks ago. It took quite a while to get back into the swing, but I finally worked on the car some more last week/weekend!

I had to figure out a brake mounting solution. There is a bracket for the rear brake lines that go from the soft lines coming from the body, to the rear axle. The bracket mounts to the top of the axle near the diff. Then two hard lines divert from there to either side of the axle. The factory rear axle has a mounting provision for the bracket, but the Moser does not, so I had to create a place to mount it. I ended up putting it on top of the torque arm near where it bolts to the axle. The chosen spot was a bit further away from the driver side than factory, so I had to bend and flare a new, longer line for that side. Then I bolted up and connected all four calipers. At this point, the brake system is fully assembled and sealed up!

I also set final torque on the diff cover load bolts and jam nuts.

Next steps:
* Fill diff with fluid + additive
* Reinstall bumper and reassemble front end (headlights, splash guards, inner fenders, bottom half of SSRA)
* Grease all the zerks and fit them with dust caps
* Fasten a couple cable and wire loom guide clips
* Install the wideband O2 sensor that finally came last week
* Fill and bleed brakes
* Put the wheels on and set the car on the ground
* Fill transmission with fluid
* Charge air conditioner
* Fill and bleed power steering
* Apply some dynamat on the area around the trap door -- this is the biggest source of boomy road noise
* Reassemble the interior (carpet, seats, center console)
* Reinstall hood
* Do some final torquing on the suspension with it loaded
* Check driveline angle
* Adjust the McLeod clutch master
* Put together a workable tune
* Get it aligned
* Finish the fuel pump trap door (an actual hinged door with an airtight seal)
* Continue working on the tune
* Get my LCA relocation brackets welded on (bolt-on brackets aren't compatible with the Moser)
* Eventually, get a professional dyno tune

The end is definitely in sight. It's getting cold here in Michigan, but there's a chance I can get it on the road a bit before the county puts down any salt.

Last edited by JakeRobb; 11-06-2023 at 12:23 PM.
Old 11-06-2023 | 02:38 PM
  #53  
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Re: 500whp LS3 swap build!

👍 👍 👍 👍
Old 11-09-2023 | 10:56 AM
  #54  
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Re: 500whp LS3 swap build!

Only a little bit of time to work on it so far this week.

I filled the diff with fluid+additive. I had a little manual transfer pump with a pump like on a soap bottle. Doing that under the car was incredibly tedious; took like forty minutes to do 2.5 quarts, and my forearms were sore the next day.

I greased all of my zerks last night. In the process I found that I had installed one end of one of my rear LCAs upside down, so the zerk wasn't accessible. I had enough time to get that unbolted and flipped around. Still need to bolt it back in and grease it.

I put the bumper back on. It's not fully fastened yet; just the alignment pins where it meets the fenders and the five push-in fasteners that hold the top part. But it's out of the way, which is huge, because this whole project is happening in a very confined space and the bumper was taking up a significant portion.


Old 11-09-2023 | 11:19 AM
  #55  
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Re: 500whp LS3 swap build!

Do you have an LPW (or other brand) cover on the Moser? Fill cap is more accessible???
Old 11-12-2023 | 09:34 PM
  #56  
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Re: 500whp LS3 swap build!

Originally Posted by Injuneer
Do you have an LPW (or other brand) cover on the Moser? Fill cap is more accessible???
I have a Moser aluminum cover. The fill cap is blocked by the panhard bar, which is annoying!

Didn’t have any time for the car yesterday, but I had a super productive day today:

1. Cut off and ground the part of the brake line brackets for the rear axle that go around behind the control arms; that part isn’t compatible with the Moser. Got them nice and smooth so they’re ready to be painted with POR-15 later when I do the axle.

2. Bolted those brackets back on (they share the rear LCA bolt) and reattached the parking brake cables.

3. Greased that last Zerk. Found that the dust caps I bought are for brake bleeders, not Zerks. Ordered proper caps.

4. Bled the brakes. Fitted them with dust caps.

5. Finished installing the bumper.

6. Installed the headlights. Verified they’re functional.

7. Installed the lower portion of the SSRA.

8. Installed my lower splash guards and air dam.

9. Installed the driver seat. Verified the power seat is functional.

10. Installed the lower shift boot.

11. Installed the upper and lower center console.

12. Ordered a pack of those little christmas-tree fasteners that hold wire looms. A couple of those in various places on the car broke on removal, and I need a few fresh ones to tie things together properly.

The clips will be here Friday. Once I have those installed, it’s time to bolt up the wheels and set the car on the ground!

Last edited by JakeRobb; 11-16-2023 at 09:02 AM.
Old 11-13-2023 | 09:06 PM
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Re: 500whp LS3 swap build!

Awesome stuff!
Old 11-16-2023 | 09:07 AM
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Re: 500whp LS3 swap build!

The wideband O2 sensor I ordered a couple months ago finally showed up. I had totally forgotten about it! One more thing to do before I can set the car down...

I didn't have much time last night, but I've installed it in the pre-existing bung in my Kooks header, and I've partially run the cable up into the engine bay. Need to tuck it in behind the heat shields, figure out a good path, and get it tied in. Then I need to decide where I'm going to mount the controller box, and then wire it into the PCM. I'll be using my EGR circuit (which is present on the PCM, but unused on '01-02 LS1s) to feed the signal into the PCM so that I can datalog it.
Old 11-18-2023 | 08:52 PM
  #59  
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Re: 500whp LS3 swap build!

Yesterday:
  • Installed the shifter **** and boot.
  • Fastened a couple things with the christmas-tree/wire-loom clips (they came early!).
  • Tried to fasten the under-dash panels. They take christmas-tree fasteners. I know the part number I need, but I can only find those on eBay for ~$25 each plus shipping, and I need three. I bought a similar-looking fastener for a different application in hopes that it would be right, but no. Now that I know better, I've ordered something else that I think will fit. More details here.
  • Found out I don't need to reinstall these clips.

Then today:

I opted not to get under the car to work on the wideband wiring, so I worked on the interior instead. The christmas-tree fasteners I needed to button up the under-dash panels came, so I installed those, and I finished fastening the center console (hadn't done the two forward screws last week).

Then I made a bunch of progress on my fuel pump service door. I've applied the seam sealer and have it pinned down with Cleco fasteners. Tomorrow, the Clecos come out and rivets go in. Then I need to get some adhesive weatherstripping for the underside of the door, and then the door is done! After that I can replace the carpet and button up the rear interior of the car.
Old 01-09-2024 | 11:30 AM
  #60  
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Re: 500whp LS3 swap build!

I missed a bunch of updates. I have a small handful of things that are done, and a large handful of progress updates.

The WB02 wiring is tucked. It runs up the frame rail behind the heat shield, then up the shock tower beneath the brake booster. From there I routed it back around the top of the booster, and then across the other side alongside the throttle cables. The end of the cable is tucked in by the PCM. I’ll mount the module somewhere over there and wire the 5V output into the PCM harness via the EGR pins (unused in 2001-2002 cars), such that I have permanent access to the data via HPTuners. The module has a separate output for a gauge if I decide to add one; for now I’m going to keep the interior looking stock.

I had a bit of trouble with the throttle, which turns out to be because I misunderstood the cable adjuster situation there and, rather than using the adjusters to take up all the slack, I had used them to create as much slack as possible, leaving me unable to open the throttle past about 50%. Whoops! Anyway, that’s resolved now. Took like 30 seconds once I figured out the problem. The throttle cable adjusters are a bit unintuitive — you’re not actually adjusting the cable. You’re adjusting the sheath! If it seems like the cable is too long, you open up the adjuster and make it longer. That takes up more of the cable within the sheath, reducing the length that protrudes from the end of the sheath. Now I know!

For a while I had an issue wherein the car would starts, but won’t idle -- I have to coax it with the throttle continuously. I first discovered that the minimum TPS % was 0.4%, which explains that — the PCM will only try to control the idle if it’s at 0.0%. I did a TPS relearn, and now it reads 0.0% like it should.

Next: TPS voltage ranges from 0.14v-3.85v. That’s too low; anything below 0.2v sets a code (and I’ve observed that it’s set). The solution here is to unscrew the TPS sensor on the side of the throttle body, then clock it slightly until the voltage is in the desired range. Ideally it should be 0.6v - 4.6v. I unbolted the sensor, clocked it around until I saw a better voltage range, then centerpunched, drilled, and tapped new mounting holes. I now get a solid 0.63 - 4.41v through the throttle range. Perfect! Although it seems like my throttle cable is stretched; I can only get to ~95% throttle via the pedal. I've ruled out pretty much every other cause. I haven't decided what to do about that yet, but I'm not going to be going anywhere near that much throttle until the wideband is installed, so it doesn't matter for now.

With all of that done, it still wouldn't idle, but a tiny tweak of the throttle stop screw fixed that. Now it idles on its own, and it sounds pretty good IMO!


Speaking of tuning: I have an HPTuners MPVI3, a USB-C cable, and an old Intel Macbook Pro running Windows 10 via Boot Camp. This setup works pretty well; I’ve started educating myself about what values to watch during the tuning process, and about the tuning process itself. I’m learning tons, and the folks at the HPTuners forums have been super helpful. The VCM Suite software leaves a lot to be desired here in terms of intuitiveness. I wonder if EFILive is as bad….

Intuitiveness aside, one of my tuning struggles so far has been getting the laptop to connect to the MPVI3. After a ton of experimentation, I've discovered the right sequence: connect the MPVI3 to the laptop first, then wait for the audible "new hardware detected" chime. Once that happens, connect the MPVI3 to the OBD2 port. I bought an OBD2 port extension with a 90º OBD2 end so I can have the laptop connected without having to worry about hitting the cable with my leg (especially the little USB-C cable going into the MPVI3).

I have an initial tune file with the right cam and injector data (and lots of other initial configuration stuff like cylinder volume and gearing) and the MAF sensor artificially failed, so the computer will run in speed-density mode. All I need to do is write that to the PCM and I can start dialing in the VE tables. Currently restricted by weather and schedule; there's snow on the ground now, and I'm extra busy in the winter, so while I've had that tune file ready for about a week, it still exists only on the laptop.

Once I'm happy with VE, I'll re-enable the MAF and dial in the calibration.

In other news, my hood won’t close on the Hawks 104mm lid. It’s super close; maybe 1/3” of additional clearance needed. I need to figure out what I’m doing to make room. Hawks product listing page says that it normally fits Z28s with no issue, then they add that a couple people had to do some clearancing. I’m not sure why mine would be in that small group. I can figure this out, but it sure would have been nice if they had provided more information on the modifications others made.

I have my fuel pump trapdoor almost complete as well. I just need to add some seals and sound deadeners, do some cleanup, and then reinstall the carpet.

I've acquired some bits and pieces I'll need to do a nice, clean wiring job on the wideband. Just need time now!

Last edited by JakeRobb; 01-09-2024 at 11:42 AM.
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