The Mule rides again (sort of) - pics.

[The Dark Side of Will]

This is how much I moved the expander block inboard.



Here's what the P-Brake looks like by itself:





Much larger gap from the expander block to the drum





And the assembly



Here is a Dustbuster knuckle on the parking brake assembly. The parking brake would work with this knuckle, but the stock service brakes would not work with the parking brake.



Here's an interesting tidbit... I designed the expander block to the "centered" on a radial line from the axle center line. Because the adjuster plunger is thicker than the fixed plunger, this puts the shoe *slightly* off center in the drum, resulting in light contact. I have updated the expander block and backing plate design to compensate for this, BUT new expander blocks will be expensive to prototype. I'm confident enough that I have the design nailed down to order the hats from Coleman now.

[The Dark Side of Will]

This is from a couple of weeks ago now, but will be progressing this weekend.
I'm shining up the V in preparation for having some acid pits welded up (should I braze them instead?). After that, I'll throw on some Cerakote MC-5100, and probably clear POR-15 on top of that.
I'll also be working on the outer sides of the block and lower crank case as well. I'll definitely MC-5100 those... not sure about adding the POR-15.

The cast-in-place iron liners make the block a bad candidate for anodizing, but the lower crank case does not have any ferrous material in it, and thus could be a candidate for anodizing. The oil pan could be as well, if I drill out the rivets that hold the windage tray in place and remove the tray for the anodizing bath.

[ericjon262]

Any reason you didn't pick up a new block? A whole engine can be had pretty cheap, even here in the PNW.

Either way you go to fill the pits is going to require either a ton of preheat, or some insane amount of current. I recommend preheat, but I'm also nowhere near a professional welder.

[The Dark Side of Will]

I've put a lot of time into this block in the form of installing Time-Serts in the head and main bolt holes (40 inserts!) as well as porting the bay-to-bay breathing windows inside the crank case. It's also a '93 which has pre-drilled block drains from the factory. Those are handy.

I was thinking hard about updating to a '05+ block and 58x engine controller. I concluded that wasn't a great choice, but that was also before I knew I was looking at new pistons and rings. New pistons and rings will be expensive, especially if I opt for TS's "diamond finish" processing, which I"m likely to do. A new block will be a bunch more work for me, but I'll be able to re-use pistons and rings. I may be able to have the prototype machinist I've been using install all the inserts and drill/tap the block drains.

The head gaskets are the same '93 to '11, as are the lower water pump gaskets... I could drop my heads onto an '05 block.

Also, if GM did not mess with the die that casts the left side of the engine, then the boss for the older crank sensor may still be there. I could have it machined and then assemble it with the crankshaft for the engine management I want. I could put it together with the old style crank, then swap in the 58x crank later.

The 58x computer would require me to obtain and wire up LS coils... not a huge deal, but extra work associated with that swap.
I wanted to revise the harness extensively anyway, though...

[ericjon262]

That's completely understandable. I didn't have any real block work done to mine, and the heads would be off either way, so it made sense for me to so it that way, but if you picked up a new one, you could have built a dry sump for it!

[The Dark Side of Will]

Lol... I can build a dry sump no matter what... it's just time and money (Well... and packaging)

Dammit, now I've been thinking about the block issue... Using my current block is a known path, but expensive because of the pistons & rings requirements.

Common expenses:
Bore honing
Head gaskets
Block anti-corrosion surface treatments

Differentiating expenses, Current:
Pistons
Coatings
Rings

Differentiating expenses, New:
Block
Time-Sert installation & misc machine work
Porting bay-to-bay breathing windows
Line-honing (depending on what lower crank case I use)
Gas porting current pistons
LS coils & wires
58x Controller & harness build (buy a Caddy harness, maybe even buy another Fiero harness and MAKE a new engine harness; also DBW throttle conversion)


Here are some good photos of a 58x block:
https://www.ebay.com/itm/253398560507

The Northstar block was always die cast, except for the supercharged engines.
Looking through the pics of that auction, and being familiar with Northstars, I can see that GM did not modify the dies that form the left and right outboard faces of the block and probably not the timing drive compartment or bellhousing face either. Modifying dies basically means making new dies, and that is expensive. They just omitted some machining operations to existing bosses on the current castings, actually saving money on those operations. The block drain bosses are there, the early crank sensor boss is there. There's a bolt boss that my intermediate shaft bracket attaches to that is not drilled, but that can be drilled.

However, they had to make a new valley die in order to add the crank sensor boss, so they also added some extra stiffening ribs. These are probably mostly for noise reduction or analytical reasons. I like block stiffness improvements, even if they're not "necessary" to make the power.

The lower crank case has always been a sand casting, and thus much easier to modify/update than the die casting.
The photos from the auction above show that GM ditched the lower crank sensor boss from the lower crank case, as well as updating the casting for a three bolt mounting for the oil filter adapter.

Also, the pan on this engine does *NOT* have the boss of the oil level sensor machined. Weird. I thought that would be standard Cadillac fare by now.

However, this auction shows the lower crank sensor boss still on the lower crank case, but also the 3 bolt oil filter mount; AND the block has the boss for my intermediate shaft bracket drilled, as well as the oil level sensor in the side of the pan:
https://www.ebay.com/itm/333371327872

Weird. Should I go ahead and snag a 3 bolt filter adapter with oil cooler connections? Those are a bit rare.
Of course if I could find a Supercharged Northstar crankshaft, that would kind of cement the deal, because then I'd have a fully forged bottom end, j0!

[ericjon262]

DO IT! lol!

[The Dark Side of Will]

but if you picked up a new one, you could have built a dry sump for it!

This has always been an option and only requires so much effort... https://www.drysump.com/index.php/oil-p ... ow-profile



The left-most connection is in a completely horrible place for under-pan exhaust routing, so I'd have to go a different way with that one.

[The Dark Side of Will]

So I have been thinking about the block.
The real question is: Can I get a crankshaft from a supercharged engine?

Option 1:
2003-2005 lower crankcase with early style lower crank sensor boss machined
2006+ FWD block with early style upper crank sensor boss not machined + 58x crank sensor boss machined
This basically lets me reassemble the engine with a '93-'99 crankshaft and keep all my current wiring and controls
It requires getting the block & crankcase combo line-honed.
Although I plan to reorganize my harness for better, cleaner routing, I wasn't planning to build a completely new harness like I would have to for the 58x conversion.
Updating to 58x controls in the future would then require changing the crankshaft. While no mean feat, that's a lot simpler than replacing the block in the future.

Option 2:
2006+ FWD block & lower crank case
2005+ Supercharged Northstar crankshaft
I think the forged crankshaft is the thing that makes it worth converting to 58x RIGHT NOW.
No one on eBay has such a crankshaft, but a few yards on car-parts list the superchargers. I may be able to find a crank by calling them.
Of course starting with a virgin crank means a significant machining operation to turn down the counterweights as well... but if it were easy anyone could do it, right?

Either option, of course requires installing steel thread inserts and some other miscellaneous machining on the block.

[ericjon262]

I would make efforts to "future proof" the engine now, while it's out, especially if you really want to go 58x in the future.

[The Dark Side of Will]

It's really the siren song of the forged crank... "That's a rare factory part that I could use in a non-factory combination to make my project cooler"; that's my kryptonite

[ericjon262]

yeah, for me, I'd go for the later block either way at this point, I used to be scared of DBW throttles, I've slowly been turned, so that side is a non issue, and the engine management options explode with 58x, you're no longer stuck with the OBD 1 setup, or the 0411(admittedly, this isn't a bad option), and just about any aftermarket setup can use 58x. and you can ditch things like cruise control modules to further improve packaging.

have you considered any other coil options other than LSx? you may be able to use Atlas I6 coils and completely ditch the plug wires, and I'm sure there are other OHC coils that might work as well. it would make packaging much easier.

[The Dark Side of Will]

DBWs are old hat now... Most places can tune them. I'm trying to find one that can dial it in for 120% throttle with the pedal all the way down.

And yeah, the advantages of a 58x trigger is not lost on me. I'll also have to figure out how to do the cam sensor signal the way a 58x controller is looking for. '99 and older systems use a peg on the right bank exhaust cam sprocket. The ICM receives this signal and toggles a 5V square output every time it gets a pulse from the peg, resulting in a 50% DC 1/2x cam signal to the ECM. The '00-'05 systems use a 50% DC ridge on the cam sprocket with the ECM reading the signal directly, but the sensor is in the same place as it is on the early engines. I strongly suspect that GM changed only the castings they had to for the 58x conversion in '06, which means the '06+ cam sensor is probably in the same place. I haven't been able to find good photos on eBay.

Since the FWD Northstars all have fixed cam timing, I don't know if GM kept a simple system like that or if they moved the Northstar over to the 4x cam sensor that VVT LS engines use.

[The Dark Side of Will]

Coleman custom brake hats arrived.





The brake pilot bore fit on the brake pilot journal on the bearing is PERFECT





I did not expect them to show up in bare steel, so now I have to figure out what to do with them. Powder coat? Epoxy paint? Any piece part black oxide treatments available? Cerakote?

[The Dark Side of Will]

I just realized... I selected a standard ANSI counterbore, which should fit a socket cap screw; I would prefer an external 12pt, but I will have to enlarge the counterbore for that.

[The Dark Side of Will]

but if you picked up a new one, you could have built a dry sump for it!

This has always been an option and only requires so much effort... https://www.drysump.com/index.php/oil-p ... ow-profile



The left-most connection is in a completely horrible place for under-pan exhaust routing, so I'd have to go a different way with that one.

Hi William, We have not made those for several years, but I still have the tooling. I would need to get about $900 + screen fittings to make one now. 4-6 weeks. 50% down. Thanks

Every other component of a dry sump is a shelf item or completely custom. Do I snag one to put on the shelf for years?

[The Dark Side of Will]

I've been learning a lot about 58x controllers and realized they have some shortcomings for my uses.

58x advantages vs. current system:
-Throttle by wire
-Direct wired cruise control (if using '09 Trailblazer OS)

58x DISadvantages vs. current:
-A/C request can not be directly wired
-VSS can not be directly wired
-There is no manual transmission OS with direct wired cruise control

All 58x applications get the A/C request via CANBus data from the BCM. All 58x Applications get the VSS via CANBus data from the TCM.

FieroGuru has been running a manual transmission TCM (Pontiac G6 maybe?) that does nothing but read the VSS and transmit that over the CANBus. There is no option for A/C request that's readily compatible with a Fiero. Selecting the Trailblazer OS for direct wired cruise means putting up with a stall prone automatic transmission calibration that does not have a clutch switch input.

Without a VSS, the system loses both rolling idle and, more importantly, DFCO, which can significantly impact fuel economy. Without the A/C Req line, the ECM can neither compensate the idle airflow for A/C compressor turn-on NOR switch off the A/C compressor at WOT or high engine RPM.

There are TBW 24x applications that have integrated/direct wire capabilities for all of the above functions, HOWEVER, they are LS 24x only and not compatible with the Northstar triggering and ignition systems. The Shelby OS doesn't do TBW and the TBW 24x calibrations don't work with the Northstar's triggering and ignition systems.

The crank trigger wheels on the Northstar are in the middle of the crank and integral to the crank. I could possibly machine off a Northstar trigger wheel and maybe install an LS trigger wheel, but I will need to precisely index (will I? How is synch handled?) it to the crankshaft, if any of the dimensions even work. I don't know the relative ODs of the LS and Northstar wheels, which is a key piece of information for making this work. I can just order a wheel, though.

HOWEVER...
I just realized that I can solve *ALL* these issues *AND* end up with Lingenfelter parts in my Fiero!

https://www.lingenfelter.com/product/L4 ... hX78UdKiEI



This converts a 58x crank sensor and 4x cam sensor into 24x LS crank sensor and 1/2x LS cam sensor pulse trains. I can build a 58x Northstar and then run any 24x LS controller with this.

BAM!

[ericjon262]

just a thought, but the LX9 uses the same 24x reluctor as an LS1, and is pressed onto the crank, you could remove an LX9 wheel and install it onto your N* crank and then you don't need the box.

[The Dark Side of Will]

Have pics, dimensions or a PN?

The forged crank from the supercharged engines is only about $400 at long-time-customer pricing from the dealership... and it's 58x.

Also, I'd have to get the indexing right.

[ericjon262]

Have pics, dimensions or a PN?

The forged crank from the supercharged engines is only about $400 at long-time-customer pricing from the dealership... and it's 58x.

Also, I'd have to get the indexing right.

I don't have any dimensions, but here's a picture.

24x.png (627.82 KiB) Viewed 2236 times