My 71 Duster work in progress

[b-body-bob]

Done.

I loosened up the header flange and the front of the muffler and tried to twist that pipe with a strap wrench but that didn't change things much. Then I released the hanger behind the muffler, and that did it. I was able to just drop the hanger down one bolt hole and Bob's your uncle there's plenty of room. It'll hang down a little but it helps that it was so tight to begin with.

Raining so no test drive but I'm confident that it's fixed and that something else will crop up the next time I take it out.

 

[b-body-bob]

I pulled the distributor apart and found those springs aren't so heavy in the real world. I guess the camera really does put on 5 lbs or something like that.

If anything I'd say the timing is coming all in too soon rather than not quickly enough. Eventually I'll get it back on the ground and fire it up to check the timing at idle and above to see when it quits advancing.

 

[b-body-bob]

It would be interesting to see what is the difference between B-block distributors from FBO @ $319, Jeg's @ $156, Summit @ $180, and Firecore @ $200. Hint - I think they're all the same.

All of those have both adjustable vac and mechanical advance. Summit and Jeg's both use the same instruction sheet customized with their letterhead. The language from those sheets/pages is used on both FBO's and Mancini's Firecore pages.

 

[69.5CUDA]

i would think any ole auto parts store has/can get one for half that

 

[b-body-bob]

i would think any ole auto parts store has/can get one for half that

Those appeal to me because the mechanical advance is adjustable. They have two roller bearings, the ones you get at a parts store are going to have bushings.

You can't find something like that at a parts store and IMO some parts are worth paying for. Just look back through this thread, this ain't no time to cheap out. I still may stay with the one I've got and throw one of the FBO limiter plates in it but heck that's $40 right there.

 

[Dr.Jass]

Don't buy or use anything without a vacuum advance.

Factory distributors with the hex-shaped vacuum canister are adjustable for rate of vacuum advance, but not limit. The limit is stamped on the arm, but if you need more it's easy to grind the stops further back. Unless you're building something with a berserk camshaft, I'm not sure I see much value in an adjustable mechanical advance, since you should set it at 35-36° total and be done with it anyhow. The rate at which it advances can be controlled by inexpensive springs. The car won't have any problem with 12-16° of mechanical lead at startup/idle. My car has proven it'll start and idle with nearly 4 times that amount.

I see no benefit whatsoever to roller-bearing flyweights. Clean, oiled bushings (not greased) will work perfectly for decades, and they'll stay oiled if you put a few drops of 3-n-1 oil in the wick atop the shaft once a year. The rollers will never see a full revolution as a flyweight pivot, which means not only are they completely superfluous, they'll also wear unevenly. Bearing stiction, needles eventually jamming or falling out... what's not to love?

I'll stick with my original recommendation: $20 swap-meet/wrecking-yard OE electronic, disassembled & cleaned, with lightweight spring(s) and perhaps a bit of mucking about with the vacuum canister. Unlike the gee-whiz Chinesium aftermarket bits, the OE part was designed to work for 100,000+ miles of abuse and complete neglect. They did, wonderfully.

I pulled the distributor apart and found those springs aren't so heavy in the real world. I guess the camera really does put on 5 lbs or something like that.

If anything I'd say the timing is coming all in too soon rather than not quickly enough. Eventually I'll get it back on the ground and fire it up to check the timing at idle and above to see when it quits advancing.

In real-world driving, I would bet it's not advancing quickly enough in light-throttle acceleration, and is seriously lacking timing at cruise. The only time your mechanical curve can be perfect is at WOT. At every other throttle position (load), the engine wants more advance than the mechanical can provide at that particular RPM. Period. It's literally the entire reason vacuum advance was invented: as a load-sensitive timing adjustment. People who think it's some kind of emissions device should stop playing with cars and crawl back under their rock until the next Stone Age dawns. Their cars suck to drive on the street anyhow.

I want a timing map rather than just a curve, so I've got distributorless setups for both the Challenger and Imperial's planned turbo engine.

 

[69.5CUDA]

tbh as much as i HATE FI for various reasons....but.....doc your dead right about wanting a timing map....the "curve is "ok" so long as the engine remains simplish, the wilder it gets the more holes in the map you have due to being stuck on a curve and your stuck compensating as much as you can before you just give up and run it how it is

 

[b-body-bob]

One thing's certain, I should try to eliminate the distributor as the source of the problem before spending money and finding out it wasn't.

I just checked and nowhere local carries the Mr Gasket springs so if I do anything with it soon I'll swap for the one in the A12 to see if that helps.

I'm planning to drop the trans pan next since I've got all four corners raised up right now. My trans book has plenty of reasons for harsh shifting so I'm going to try to figure out if that's caused by any of those or at least any of them that I can check with the trans in the car.

 

[b-body-bob]

There was a lot of "crap" in the pan. Some of it looked shiny, but I'm not pulling the trans so that doesn't matter. There were no broken parts so I'm done with that. Made a helluva mess pulling the pan of course so I quit last night after cleaning that up. Will adjust the band and put it back together today.

 

[69.5CUDA]

unless you cleaned the pan before that shot..the little bit im seeing in the pan and on the filter is basicly nothing

id bet on a shift kit intentionaly making harsh shifts lol, heck could just be line presure too, i tweaked my stone stock 904 in my 67 fish too the point the 1-2 shift AT IDLE feels like youve been rearended

 

[Dr.Jass]

There was a lot of "crap" in the pan. Some of it looked shiny, but I'm not pulling the trans so that doesn't matter. There were no broken parts so I'm done with that. Made a helluva mess pulling the pan of course so I quit last night after cleaning that up. Will adjust the band and put it back together today.

That's much cleaner than what was in the Valiant's original A904, and the latter worked flawlessly.

Adjust both bands while you're there, and check the line-pressure adjustment. The further the screw protrudes through the little plate, the lower the line pressure. Do not go any lower than the factory adjustment. Personally, I crank the line pressure up for firmer shifts, which I don't consider to be harsh.

Make sure the throttle-pressure (kickdown) linkage adjustment and the valve inside the valve body is moving when the linkage moves. The trans lever should be all the way to the rear with the throttle wide open, but immediately move when the throttle's released (that's why there's a return spring for that linkage). If there's no linkage and the lever is held fully back 100% of the time, there's your problem. I've seen that kind of half-assery many times and every cheap bastard who did it hated it. That arrangement gives you max line pressure 100% of the time, and shifts extremely hard (and late). Get linkage and install it correctly. It's the only way.

The long-discontinued B&M ManualPak, which convert the valve body to full manual only, instructed the user to install the kickdown valve backward and delete the linkage entirely. It was like getting hit in the back with a Louisville Slugger. That was my first lesson that "racier is not always gooder" back in my early 20s. I couldn't get rid of that valve body quickly enough.

 

[69.5CUDA]

i totaly forgot how much fun it is to "dial in" the kickdown linkage with a tweaked line presure...let alone a after market shift kit, i found that while your right you need WOT to be al the way back, you also need to be certain your releasing enough presure on the non WOT side, and with aftermarket intakes, odd carb linkage etc you sometimes need to bend the carb to mount section to change its angle which can fix your throw, in some weirder cases you have to drill new holes to change the ratios

and yes a 2brl carb rod can be made to work but it takes some serious effort to get it all aligned right

 

[b-body-bob]

Thanks for all the advice but I adjusted the bands and put it back together. I am just flat out sick of being on a creeper under a car. I'm way too old for this stuff. At least half of my time out there is spent getting on the creeper and getting back up.

I too figure the kick in the ass second gear shift was somebody's idea of a good idea but not mine.

I put the timing light on it and it's jumping around. When I was reading about the tach drive dist that was mentioned as typical and caused by the advance coming in too quick. So I cobbed together another distributor out of two so I can see if the distributor is causing that. It's got a vac advance in it but it doesn't work so it's not plugged up. I hope it works, it's got parts from a small block dist in it but they're the same. Too bad the vac advance is different because the small block one worked. I also swapped out the "heavy" spring (the one without the big loop on it) for a purple one I had left from a MP spring kit. Hard to tell what that will do but you never know.

It has to wait until tomorrow because it's too late to start it now

 

[b-body-bob]

Well that made a difference. It fired right off, I set the timing at idle at 15* and it's rock solid so it was the other distributor making the timing jump around. The weird buzzing I heard yesterday is gone now too. FWIW you can spin that old distributor by hand and hear the advance clicking as it goes around. That was probably what the buzzing was, just a lot faster.

It's still on jackstands so I don't know how it runs yet but I'll be surprised if it still bogs down when I nail it now.

Now my decision comes down to how much does a vac advance can cost ($30 @ mancinis), and do I need that FBO limiter or not ($35). That gets me half way to the cost of a new distributor by the time I add shipping.

 

[Dr.Jass]

Set your total timing, for which you don't need vacuum advance. Do it at a fairly-high RPM if your current distributor has stock springs, say 3,500 or even more, at 35°. Bring it back down to your intended idle and see where your timing mark is. Is it 15° or less? No need for the limiter plate. That's for guys like me with idiotic solid cams that won't idle without 20+° of advance. I don't think I've seen a hydraulic cam that would necessitate it, although some of the newer grinds might. I've seen a 305° (adv) juice cam with over .540" lift idle fine with 35° total and the stock advance stops. I realize you don't know which cam you've got, but I bet it's not that large (that was the biggest thing available at the time).

I know you're just looking for reasons to justify spending money on a new Chinese distributor, but Standard Motor Products part number VC173 would be about $20-$25 if you shop locally (which can be done, y'know). That's the number they list for a '70 383; the design is the same between points and electronic. Based on the hex stamped into it, it should be adjustable for rate (the hex is SAE "code" for adjustable rate). I haven't looked at the distributors you're shopping, but sticking with the better-made factory parts means easier (local) parts availability in the unlikely event of failure, be those parts new or junkyard.

I'm not sure what's going on with the tach-drive distributor, but I doubt the advance would engage spinning it by hand. It sounds more like a shaft issue, be it worn bushings or a beat tach drive gear. Mine displays no such silly behavior. It's also possible the reluctor is hitting the VR sensor... did you check the gap? It's all academic, since there's no vacuum advance.

 

[b-body-bob]

Yeah I checked the gap in the tach drive, it's got some. But if I spin it, it clicks. Someday I'll look at again but I'm done with that thing. One day, I had the key on monkeying around with something, and it started buzzing loudly. I got it to repeat. The freaking thing is haunted or something. It's got a name on it "Shaffer".

Thanks for that part number, NAPA has "Call Store for availability" or "Home Delivery, Get it by Thu, Oct 14" at $20.50. Sold. Will call tomorrow.

Yeah I need to get Gina's help to rev it up to science out the RPM and limit. It might be fine as is. I'm real happy with this $0 fix, and it really was a fix. Night and day.

FWIW all I know about the cam so far is that it uses stock rockers.

Another FWIW - with the car on stands and the car in gear, I can't stop the rear wheels. The brakes are tight, going by the fit of the drum, but it's all new parts so it hasn't been heat cycled or anything. I've mentioned before it doesn't stop real well. I expect it to get better as it wears in. No rear end noise noted, and the speedo doesn't work.

 

[b-body-bob]

NAPA wants 11.99 to ship that to the store from Chicago, so I'm investigating ship from home to try to get it cheaper. $35 gets you free shipping and I could surely use some Go-Jo and/or shop towels.

 

[b-body-bob]

NAPA wants 11.99 to ship that to the store from Chicago, so I'm investigating ship from home to try to get it cheaper. $35 gets you free shipping and I could surely use some Go-Jo and/or shop towels.

I searched but never found hand cleaner or shop towels, but I found a pretty jazzy 8-outlet surge supressor that will be handy on the back of my work bench. $35.48 total, so free shipping. They're coming on two separate days so separate packages. They didn't make much on this deal, esp if they were just covering costs on that $11.99 charge from the local store. I expect the vac canister to be here Weds.

 

[Dr.Jass]

Yeah I checked the gap in the tach drive, it's got some. But if I spin it, it clicks. Someday I'll look at again but I'm done with that thing. One day, I had the key on monkeying around with something, and it started buzzing loudly. I got it to repeat. The freaking thing is haunted or something. It's got a name on it "Shaffer".

It's clearly possessed by David Letterman's band leader. Paul always knew the buzz.

Yeah I need to get Gina's help to rev it up to science out the RPM and limit. It might be fine as is. I'm real happy with this $0 fix, and it really was a fix. Night and day.

Talking with Stretch today, he's got the timing on his original 340 distributor set at 36° total. At the stock idle listed on the fender tag, it's at 12°. I didn't ax if he messed with the advance springs, but if memory serves he swapped out just the heavy one.

I wouldn't be at all surprised to find your cam is one of the old MP grinds. They were silly popular and the previous owner sounds like he was old-school. Dumb, but old-school dumb.

Another FWIW - with the car on stands and the car in gear, I can't stop the rear wheels. The brakes are tight, going by the fit of the drum, but it's all new parts so it hasn't been heat cycled or anything. I've mentioned before it doesn't stop real well. I expect it to get better as it wears in. No rear end noise noted, and the speedo doesn't work.

Back 'er up a few times, braking to stop it. Let the self-adjusters do their thing. You did install the self-adjusters and their attendant parts, right?

I found a pretty jazzy 8-outlet surge supressor that will be handy on the back of my work bench. $35.48 total, so free shipping. They're coming on two separate days so separate packages. They didn't make much on this deal, esp if they were just covering costs on that $11.99 charge from the local store. I expect the vac canister to be here Weds.

They're basically bypassing the local store, but feeding them a little monetary sunshine for being there--NAPA wouldn't be a thing without neighborhood stores. Based on my experience with warehouse margins, etc. NAPA corporate probably made about $10 on the canister and $7-$9 on the surge suppressor. They'll throw your local store around 10% of the sale, and with a large shipping-company contract it'll probably cost 'em about $5 to ship. They didn't make much, but they're also banking on you ordering large-ticket, high-margin items in the future based on your experience. Regardless, the piggy bank gets heavier with every penny you insert.

 

[b-body-bob]

It's clearly possessed by David Letterman's band leader. Paul always knew the buzz.

A buzz is just a high speed click track. 3000 BPM baby.

I pulled the distributor apart to the springs and weights and it still clicks. I don't see the weights moving, so pretty much the only thing left to make a nose are the bearings and they do feel notchy. So much for selling it to the one person left on Earth that would want it.

I wouldn't be at all surprised to find your cam is one of the old MP grinds. They were silly popular and the previous owner sounds like he was old-school. Dumb, but old-school dumb.

I doubt the guy did anything with the engine. Supposedly he put a quarter panel on it, but the only welder he had was a flux core job and that definitely didn't do the welding there. Whoever did it knew what they were doing, and this guy was a plumber working in his driveway.

The cam is probably either an MP or a Crane, because most of them were, but there's a big Erson decal on the elephant ears. I hope I never have to find out TBH.

Back 'er up a few times, braking to stop it. Let the self-adjusters do their thing. You did install the self-adjusters and their attendant parts, right?

I don't know how anyone will get the drum off if they get much tighter, but I agree I need to do that and see if it helps. It could probably use a few ride the brakes down a hill trips too to break in the surfaces.