rattle_snake's random shop projects v0.1

[rattle_snake]

Pulled the trans pan and made a big mess as usual. But not next time. Went 3/8 MPT so I can use a coolant temp sensor as a plug.


When weldment needs to be leak free, it's helpful to look at the back side. The area between the bung and pan rail was hard to get to and cold. But it doesn't leak.


Installed a new filter. There was minimal clutch material in the bottom of the pan.


Pulled the trans tailshaft off to replace the output bushing.


I'm hoping that a new bushing will solve the leak at the tailshaft, even though it has a new seal. The driveshaft exiting while driving couldn't have been a good thing.


Press for the win


Another new seal. I smoothed the casting on the end so it seals better to a cover/plug.

 

[zmotorsports]

Nice job Justin. I machine male threaded bungs for transmission temp. adapters/drain plugs a lot and weld them in. For a cleaner look, I try to weld the bung in from the backside whenever possible. Also, the tailshaft bushings are often overlooked on high mileage vehicles when there is a tailshaft leak. I've found these to be worn in many situations and where a new seal will continue to leak. Great job addressing both.

 

[rattle_snake]

Bought a cheap engine leveler. Needed some modifications. Added some thrust washers and tightened up the jack screw.


Cut the angle off the rear mounts


But the added gear prevented the lift from going high enough. So had to set motor back down and shorten up the chains. Luckily I had an old tire to set the motor on.

 

[ntsqd]

Nice job Justin. I machine male threaded bungs for transmission temp. adapters/drain plugs a lot and weld them in. For a cleaner look, I try to weld the bung in from the backside whenever possible. Also, the tailshaft bushings are often overlooked on high mileage vehicles when there is a tailshaft leak. I've found these to be worn in many situations and where a new seal will continue to leak. Great job addressing both.

What I eventually arrived at is three healthy tacks on the outside (to take the install torque) and a TIG bead of silicon-bronze all the way around on the inside. To do this I machine a piloting step in the face of the bung so that the bung is flush on the inside of the pan. Almost 30 years of doing it that way and I've never known one to develop a leak.

 

[rattle_snake]

I had not considered putting it on the inside This particular bung although '3/8 NTP' was not tapered and could go either way.

I did use the lathe to machine a step in the bung, self center, but it was a little too deep.

Learned some good stuff today, thanks! I need more tooling haha.

 

[WoodsTruck]

You could have also bypassed the chain hook on the cherry picker and went direct to the balancer trolley for a couple more inches of lift.

 

[rattle_snake]

Ok thanks that would help. I did shorten the chain above the hook by one link so the motor isn't at 90* to the hoist.

 

[zmotorsports]

What I eventually arrived at is three healthy tacks on the outside (to take the install torque) and a TIG bead of silicon-bronze all the way around on the inside. To do this I machine a piloting step in the face of the bung so that the bung is flush on the inside of the pan. Almost 30 years of doing it that way and I've never known one to develop a leak.

Similar, only usually nothing on the outside, but it depends on the application. Machined step on the bung, then TIG weld the inside. No issues either.

 

[ntsqd]

I felt like using the Silicon-Bronze filler made the sealing less of a question, but didn't want to trust it to resist the torque of installing whatever was going in that bung. It probably would be fine, I just didn't want it coming back to me. The first time I did it the bung was a drain for a drag racer's 9" housing, so it wasn't going to be a once and done install. It worked so well that I've just not varied the process since then. There is some concern about the outer welds competing with the inner welds, which is why I only use heavy tacks and not a full circumference weld on the outside.

 

[rattle_snake]

New cooler lines, soft, out of the way of header install/removal.








Put in a new u-joint on trans end so everything is new. But the trans end is a 1330 and axle end a 1310... Aghh..


Engine coolant sensor used for trans temp, because free.


All back together. Coolant test before fluids? yes but fail. So break it back down and new timing cover gasket, regular fiber this time instead of the super thin steel/rubber deal.


Try again...


I bought 3 more shades of blue vinyl and picked the best match for some new stickers.

 

[rattle_snake]

Cheap trans dipstick works but needed some help. The o-rings were too small and didn't stay in place on trans casting. Found some that worked well enough. The HVAC box makes for a more difficult solution on the top end. I made a single hole bracket to work with the evap cover.


Clocked the setup to put the hose out of the way of the headers. The rigid dipstick and hard cooler line interfered with header in/out.


The 3AN oil pressure gauge line wasn't really long enough, so I bought a kit of 3AN teflon hose/fittings. Black would be better but not available at the time. So Army/Navy colors. Now I can make up my own custom hose assemblies. Next is nitrous purge when I can decide on how to do it.


Fluids. Expensive. Since trans fluid was new, I put that **** back in. The dipstick came with an odd fitting and 3" of clear hose. No documentation. Assume it was for filling, it fit poorly so a fail. I machined an o-ring groove in the fitting on the lathe and found a suitable o-ring for a proper seal. Then was able to siphon the fluid back in. Which came back out on the floor. I used the transmission's rubber pan gasket dry and was leaking all around. I had hammered all the bolt holes back flat on the pan and didn't over torque to cause again. But the bolts needed to be fairly tight to not leak.

 

[rattle_snake]

Cam break-in is stressful. There are many way to argue about. I do it this way:

• Make sure no leaks. Coolant, oil, trans fluid. Distilled water in cooling system, because murphy's law.
• Use real break in oil, driven BR30. Same price as other hot rod oils.
• Set idle screw in to prevent idle on fire up.
• Disable vac advance on distributor, plug hose.
• Pre-wire timing light, paint marks on balancer.
• Pre-lube oil system right before startup. Minimal amount. Get air out of the system, verify pressure. Don't want to wash the assembly lube off the cam. I use an old Dizzy modified for the purpose.
• Set crankshaft at 12*TDC compression, and place dizzy rotor just CW of Plug #1 on cap.
• Prime fuel system and put a few shots down the carb. Have fire extinguisher (and/or beer) handy. And hearing protection.

Then fire, set engine speed 2-2.5k, timing to 20-30*. Enjoy the anxiety and piss off the neighborhood for 20 min. What can go wrong?

Then idle down and set base timing, plug in vac advance, reset idle speed and get to hear the new idle.

All went well as far as I can tell. All 8 primary header tubes were slightly glowing red. Hood on roof so didn't drive it, just a burnout. Sound is louder, sharper. Throttle crack is holy **** now.

Next step is to address the items needed for road test, seat rings. Then tune the carb with wideband.

 

[rattle_snake]

Finally address the poor fitment of the camper shell on the 72 F250. It was hitting the back of the cab and messing up the paint. Problem is the angle of the front wall, not the length, so I broke the old turd down to modify the frame. Can't take the skin off easily unless most of it, so worked from the inside/front by pulling it all out.


I cut 1" out of the upper structure to steepen the angle. The typical putty tape was used to seal, which I hate. Didn't have any on hand so I used a tube of self level, which I despise even more, and made a big mess out of it. But it is sealed. Also had to cut down the roof rack. I hacked it and threw in some rivets, to avoid swapping to the spool gun for AL welding. A lot of time and effort to look the same as before.

 

[zmotorsports]

Glad to hear a successful fire Justin.

Your initial fire process is similar to mine. Although I generally pull a vacuum on the cooling system for a bit longer than normal and actually fill with mixture of distilled water/glycol during the initial fill. Maybe I've just been fortunate that way.

Initial starts are always stressful, no matter how many a person has done just because there are so many variables and so many things that can go awry.

I like the flexible trans. cooler lines, I'm running similar on my Duramax vs. the OEM rigid lines that were known to fail. I really like all of the black flex hoses, looks nice and clean.

 

[rattle_snake]

Thanks Mike. Glad to have the process behind me. Still really hot here, so I waited for sundown and got lucky with a rainstorm right before, so 85 instead of 105 ambient.

I hadn't thought to vacuum the coolant/Dist. water in. That would be slick. Going to try that next time. I assume you have to vac from highest point. Do you have a radiator cap setup for this?

I thought about using softened well water for initial fill, but distilled is only a few dollars, negligible in total cost of the job. Gives one more flush cycle, then I can add the old antifreeze back in and top with distilled. I think half of the bucket has evaporated but end concentration will be the same as before.

I've somewhat avoided soft trans cooler lines. OEM were steel, robust. but hacked up and time for something decent. I bought an entire kit of cheap AN hose and fittings for less than just the hard line. The soft lines are easier to work with.

 

[rattle_snake]

Anyone used the newer GM style power steering pumps on universal applications?
something like this?

Lares Corporation 2758 Lares Remanufactured Power Steering Pumps | Summit Racing

Free Shipping - Lares Remanufactured Power Steering Pumps with qualifying orders of $109. Shop Power Steering Pumps at Summit Racing.

www.summitracing.com

 

[Bigblue&Goldie]

I tried one with a hydraulic assist setup and the size of the resevoir was a problem for the volume and temp of fluid. Not overly surprised, but we were trying to go for easy packaging and light weight. I wouldn't hesitate to run one on the truck with a regular box; should be better than the whining Ford pumps.

 

[zmotorsports]

Thanks Mike. Glad to have the process behind me. Still really hot here, so I waited for sundown and got lucky with a rainstorm right before, so 85 instead of 105 ambient.

I hadn't thought to vacuum the coolant/Dist. water in. That would be slick. Going to try that next time. I assume you have to vac from highest point. Do you have a radiator cap setup for this?

I thought about using softened well water for initial fill, but distilled is only a few dollars, negligible in total cost of the job. Gives one more flush cycle, then I can add the old antifreeze back in and top with distilled. I think half of the bucket has evaporated but end concentration will be the same as before.

I've somewhat avoided soft trans cooler lines. OEM were steel, robust. but hacked up and time for something decent. I bought an entire kit of cheap AN hose and fittings for less than just the hard line. The soft lines are easier to work with.

For pulling a vacuum and filling Justin, I just use my Air Lift coolant system. You may have seen it in use on my thread as I really don't do any cooling system without it. I initially bought it about 30 years or so ago to fill snowmobiles as the cooling heat exchangers were problematic to get the air out, but quickly realized they work great for any cooling system. I especially like that I can pull a vacuum, walk away for a half hour or so to verify there are no leaks. If the vacuum begins to leak off, I know I have a leak somewhere, usually a clamp, then it's just a matter of tweaking one here or there until the leak stops, then pull a vacuum again and verify it's holding. So much nicer and cleaner than having to dump coolant to fix something. This way I know for certain the system's integrity is sound before ever introducing coolant into the equation.

I highly recommend one Justin. You won't regret it.

 

[WoodsTruck]

The Bronco upgrade is to a Saginaw pump. That's what I did on mine when I went from the 6:1 box to the 4:1.

66-71 Bronco 351W Steering Pump Kit

Power up with 66-71 Bronco 351W Steering Pump Kit. Enhanced control and performance at TOMS OFFROAD. Click to purchase!

tomsoffroad.com

 

[ntsqd]

If you're using a 90's era serpentine drive system (NOT the Explorer system!) there is an easy Saginaw 'canned ham' type PS pump conversion using the E series parts from the same era. There's a guy on the GFB and FSB forums who pulls those assemblies in JY's and sells them for pretty reasonable. Don'ttellmywife racing or something close to that.

The Wagon came to me with some aftermarket serpentine drive kit on it's SBC that uses the later type Saginaw PS pump. When I had Lee Power Steering rebuild it they told me that they always convert them to a remote reservoir. I had assumed it was because of the cheesy way that the stock reservoir is held on, but then I did some simple math. The pump that I got back flows 3.0 GPM (pretty common GPM for any up-rated PS pump) and the OEM reservoir might hold a pint? That means that the pump is completely cycling all of the fluid in the reservoir thru the PS system every 2.5 seconds! Even if it holds a quart that's still a complete fluid exchange every 5 seconds.

 

[rattle_snake]

I tried one with a hydraulic assist setup and the size of the resevoir was a problem for the volume and temp of fluid. Not overly surprised, but we were trying to go for easy packaging and light weight. I wouldn't hesitate to run one on the truck with a regular box; should be better than the whining Ford pumps.

Agreed, this is a street machine and has minimal load on the pump.

For pulling a vacuum and filling Justin, I just use my Air Lift coolant system. You may have seen it in use on my thread as I really don't do any cooling system without it. I initially bought it about 30 years or so ago to fill snowmobiles as the cooling heat exchangers were problematic to get the air out, but quickly realized they work great for any cooling system. I especially like that I can pull a vacuum, walk away for a half hour or so to verify there are no leaks. If the vacuum begins to leak off, I know I have a leak somewhere, usually a clamp, then it's just a matter of tweaking one here or there until the leak stops, then pull a vacuum again and verify it's holding. So much nicer and cleaner than having to dump coolant to fix something. This way I know for certain the system's integrity is sound before ever introducing coolant into the equation.

I highly recommend one Justin. You won't regret it.

Ah OK. A dedicated setup. I have an A/C type vac pump but hesitant to use with coolant and walk away. I do have a home made liquid separator I use for brake fluid. Maybe I should make another one out of a bucket only for coolant.

The Bronco upgrade is to a Saginaw pump. That's what I did on mine when I went from the 6:1 box to the 4:1.

66-71 Bronco 351W Steering Pump Kit

Power up with 66-71 Bronco 351W Steering Pump Kit. Enhanced control and performance at TOMS OFFROAD. Click to purchase!

tomsoffroad.com

Yes I've done several sag swaps. Great for off-roading as you can shim and drill for improved pressure/flow, but not needed in this application. They are old design, large and heavy compared to modern pumps. I want small and light. Then I can move the A/C pump down, package tighter, looks better.

If you're using a 90's era serpentine drive system (NOT the Explorer system!) there is an easy Saginaw 'canned ham' type PS pump conversion using the E series parts from the same era. There's a guy on the GFB and FSB forums who pulls those assemblies in JY's and sells them for pretty reasonable. Don'ttellmywife racing or something close to that.

The Wagon came to me with some aftermarket serpentine drive kit on it's SBC that uses the later type Saginaw PS pump. When I had Lee Power Steering rebuild it they told me that they always convert them to a remote reservoir. I had assumed it was because of the cheesy way that the stock reservoir is held on, but then I did some simple math. The pump that I got back flows 3.0 GPM (pretty common GPM for any up-rated PS pump) and the OEM reservoir might hold a pint? That means that the pump is completely cycling all of the fluid in the reservoir thru the PS system every 2.5 seconds! Even if it holds a quart that's still a complete fluid exchange every 5 seconds.

no using V-belts. But yes I did a modified van pump on my 77 bronco.

There is some ******** tech on remote reservoir over on Irate. I see you are a member. Use there is fully hydro, rear steer, serious competition and $$$$.

https://irate4x4.com/threads/steering-reservoir-tech-and-demo.336707/

 

[rattle_snake]

This is what I'm trying to avoid. On my 72 w/ 460 I went to this offset reservoir to clear the A/C pump. And the sag pump really needs a rear bracket or it jiggles the fluid out the cap.

 

[zmotorsports]

Ah OK. A dedicated setup. I have an A/C type vac pump but hesitant to use with coolant and walk away. I do have a home made liquid separator I use for brake fluid. Maybe I should make another one out of a bucket only for coolant.

This is the one I have had for the past 30 or so years. There are also others available now from companies like Snap-on and many others that have a few more niceties, but basically they all function the same way.
https://www.northerntool.com/produc...|PLA|GOOG|STND|c|SITEWIDE|INTRADE|AutoRepair|{adgroup}||857740998|42214669823&gclsrc=aw.ds&gad_source=1&gad_campaignid=857740998&gclid=Cj0KCQjwzt_FBhCEARIsAJGFWVklBybD4xwFeqGKqy28NxHTUekoAYR9japjdRn16zjvB51Edu8Gx-AaAsWZEALw_wcB

 

[Bigblue&Goldie]

Justin, is there a reason other than packaging you don't go with a pump without a built in reservoir and do a remote mounted reservoir? It seems that would give you the most clearance on your AC compressor and eliminate the fluid sloshing out of the cap.

 

[ntsqd]

I did locate the Airlift tool on amazonian auto supply for a little bit less, it's in my cart. For that price I'm inclined to just buy it rather than fudging around trying to connect my Piab H120 vacuum generator to a coolant system.

Someone out there (Wildhorses?) makes a bracket to bolt the Saginaw PS pump used on LS' in the place of the Ford PS pump. Might only be serpentine applications and might not matter. I'm only dimly recalling that it exists and no details. Those pumps are really nice for package size and are a two bolt mount method that is easy to work with and rigid.

Looked at the Irate PS res link, and then watched his first Utoob. I built my own cyclonic PS reservoir without ever finding that thread. I based the design on how well designed dry sump tanks work. It didn't work, but I've learned some and I think that I now know why. Gen I is chronicled in the "Snowball" link in my sig. Gen II is close to being testable, but going to wait until Lee sends the rebuilt steering box back to me and only make a PS fluid mess once. I went remote on Snowball because of the hydro-boost, it just made things easier. And then was sort of forced into it again on the Wagon. Partly because of how Lee PS does things and partly because of the H-B on it, too.

 

[rattle_snake]

This is the one I have had for the past 30 or so years. There are also others available now from companies like Snap-on and many others that have a few more niceties, but basically they all function the same way.
https://www.northerntool.com/products/550000-uview-airlift-kit-cooling-system-replacement-parts-6736220?cm_mmc=Google-pla&utm_source=Google_PLA&utm_medium=Automotive > Automotive Repair Tools > Air Conditioning&utm_campaign=UVIEW&utm_content=6736220&ogmap=SHP|PLA|GOOG|STND|c|SITEWIDE|INTRADE|AutoRepair|{adgroup}||857740998|42214669823&gclsrc=aw.ds&gad_source=1&gad_campaignid=857740998&gclid=Cj0KCQjwzt_FBhCEARIsAJGFWVklBybD4xwFeqGKqy28NxHTUekoAYR9japjdRn16zjvB51Edu8Gx-AaAsWZEALw_wcB

Wow ok, not that expensive, seems like a win to just buy one. Thanks for sharing.

Justin, is there a reason other than packaging you don't go with a pump without a built in reservoir and do a remote mounted reservoir? It seems that would give you the most clearance on your AC compressor and eliminate the fluid sloshing out of the cap.

At the time I wanted to keep the look under the hood mostly stock. A RR setup didn't fit that. Then I went HB and needed a dual return and did the GM style offset res. Then found out that the system cooling (and fluid control) was insufficient for ******** use in the rocks with locked diffs. So I added a big cooler, but I suspect that I may still have issues with aeration and a RR would be next step. Then mod box and add ram assist.

I did locate the Airlift tool on amazonian auto supply for a little bit less, it's in my cart. For that price I'm inclined to just buy it rather than fudging around trying to connect my Piab H120 vacuum generator to a coolant system.

Someone out there (Wildhorses?) makes a bracket to bolt the Saginaw PS pump used on LS' in the place of the Ford PS pump. Might only be serpentine applications and might not matter. I'm only dimly recalling that it exists and no details. Those pumps are really nice for package size and are a two bolt mount method that is easy to work with and rigid.

Looked at the Irate PS res link, and then watched his first Utoob. I built my own cyclonic PS reservoir without ever finding that thread. I based the design on how well designed dry sump tanks work. It didn't work, but I've learned some and I think that I now know why. Gen I is chronicled in the "Snowball" link in my sig. Gen II is close to being testable, but going to wait until Lee sends the rebuilt steering box back to me and only make a PS fluid mess once. I went remote on Snowball because of the hydro-boost, it just made things easier. And then was sort of forced into it again on the Wagon. Partly because of how Lee PS does things and partly because of the H-B on it, too.

Between you and Mike my toolbox is running out of space.

 

[rattle_snake]

Been stuck on what to do with nitrous purge line. Decided to go with antenna mast hole. Unfortunately I threw away the mast base, because no radio. So I made a simple cover plate and mounted a 3AN bulkhead connector. Hose through the cowl plug.

 

[zmotorsports]

Between you and Mike my toolbox is running out of space.

Justin, just in case you didn't know, they do make larger toolboxes to fit your needs, and your tools.

 

[ntsqd]

Between you and Mike my toolbox is running out of space.

My work here is done.


Cool purge set-up!

 

[SilverJimmy]

When Snap-On introduced the Epic series of boxes at the annual tool show they had one setup over 200’ long! How big do you need?

 

[rattle_snake]

Need? Yes, all of it. Space to put it? not so much. If I had f-you money I would invest heavily.

Enablers, that's what you guys are....

 

[zmotorsports]

Enablers, that's what you guys are....

Just trying to fulfill our duties here on Garage Journal Justin. No shop nor toolbox is big enough.

 

[rattle_snake]

and doing so well...

 

[rattle_snake]

Update on the 76 F100. Had a misfire at idle. Runs fine above 2k rpm, but not below. Pulled the plugs, 3 were not firing. Called my engine builder, he suggested to move to a CDI box for a few reasons. So ordered that and a coil. And a 3" exhaust system.

I dumped the water on the ground and put the antifreeze back in. Made yet another throttle spring mount to add more preload. The Idle up solenoid was not working, poor ground path, so I soldered a wire onto the unit and made a dedicated ground wire. Now it works, however it won't push the throttle open, only hold it open. Not a big deal. Need to shim it back a bit more.

Topped off the trans fluid, really hard to read the dipstick. Yesterday was below 100*, so I rode my motorcycle to auto parts store, felt good.

With temporary AFR gauge hooked up I looked into the idle mixture. It seems too lean, once it settles down in RPM it goes leaner until stall. So I turned the idle screws out 1/2 turn and now is sits at about 13 and seems to run properly. I checked for misfire with timing light, it is gone. Why? don't know. I did mess with the plugs, and distributor wiring. Or it is just random, or Murhphy's law because I ordered a CDI box and coil.

Anyhow, I was able to do a few short pulls and AFR looks same as before, so I don't see a jet change needed yet. It boogies pretty good now. Did a few smokey burnouts, sounds ******* amazing.

 

[zmotorsports]

Justin, just curious why your engine builder suggested a CDI ignition would solve the low RPM miss? I love CDI ignitions, but have found they seem to be more beneficial higher up the RPM range than lower. I have not really had any issues with a standard coil/pickup ignition system for my mild builds, so I'm curious.

Based solely on the information that you have shared, I would suspect the reason the low RPM miss is gone now is due to fattening up the idle mixture, that may have been the cause of the misfire if there's not enough fuel to fire all cylinders.

 

[ntsqd]

What I was thinking, Lean Misfire.

Having been down that road several to many times I'm not a fan of ign boxes like an MSD on a truly streetable engine. A real Dura-Spark II module is pretty good (if you can find a non-chinesium one) and if you really feel the need to modify the ign module go with a quality HEI module. After trying everything in the Mopar world I used an 8 wire version on the Valiant and it never idled so smooth. Mildly lopey, but smooth. Ran better hot, cold, and in-between, and pulled hard all the way up to redline.

 

[rattle_snake]

Sure Mike, his reasoning was; old, DSII box is 30+ yrs. Poor performance over 5k RPM. Performance application can benefit from hotter spark. wider plug gap. In general he does not recommend things that won't help. He has an engine dyno and decades of experience.

Also this is intermediate step in performance. Next round is big cube short block, big cam, more RPM, more nitrous. Going to have to run cold plugs at high cylinder pressure. As the cylinder pressure goes up, the mixture impedance goes down, and it's takes more energy to make an electrical arc. Same for boost.

I think something electrical changed. Unless the timing light won't fire if plug doesn't. I saw random timing light triggers all over the place. The sound of engine matched the timing light behavior. Perfect above 2k and garbage below. It would not run at all on base timing. Now it is fine. I pulled all the plugs so fiddled with all the wires, cap, distributor plug. I tried swapping polarity of the pickup, which only made things worse.

 

[rattle_snake]

What I was thinking, Lean Misfire.

Having been down that road several to many times I'm not a fan of ign boxes like an MSD on a truly streetable engine. A real Dura-Spark II module is pretty good (if you can find a non-chinesium one) and if you really feel the need to modify the ign module go with a quality HEI module. After trying everything in the Mopar world I used an 8 wire version on the Valiant and it never idled so smooth. Mildly lopey, but smooth. Ran better hot, cold, and in-between, and pulled hard all the way up to redline.

I agree the DSII was good for it's day, but they are all old now and electronic don't age well. And repop's are **** as you stated. I haven't seen a drawback to the MSD or others on the street. I already ordered a summit box and epoxy type coil for the 600V output of the box. DSII distributor is ideal with it's mag pickup, hence what CDI/MSD type systems were designed from.

 

[rattle_snake]

Also I would think 2k RPM is past the Holley transfer slots/idle circuit? I dunno.

 

[ntsqd]

In a milder engine than where you're headed the MSD actually ran worse than a JY salvaged D-S II. Not by a lot, but noticeable - mostly on frosty mornings. It was harder to get it lit and keep it lit. Contra-intuitive, I know.
Both were triggered by the same dist. I took some pain to make them hot-swappable electrically. IME the MSD boxes have a much shorter MTBF than the D-S II or the HEI modules. At least the OEM such modules, unless you fail to properly heat-sink an HEI module. Then it's MTBF can be measured in feet traveled.

MISF & I did a test on those Perf. Dist HEI modules when they first came out. No change in dwell angle up to ~4500 (as high as he was willing to free-wheel the test engine), a solid 45° I'd be surprised if a D-S II was that solid up that high. Good, but not that good.

The other OEM part that worked noticeably better on that mild engine was the E-Core laminated core coil from an EFI Ford engine.

Transfer slots should be a function of throttle plate angle, but yeah, I'd think by 2k that you're tilted enough. Depends though, in a DGV the 'Idle Circuit' is a major player up to about 3k rpm. I've no idea about Holleys that way.