Highway RPMS ?

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AJ/FormS said:
>How are you gonna fit a 29" tire on a 65Dart? Does that even work?
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I had 28/11.50 15s on the back of my 65 Valiant and it had room for 29s. I think the early cars are shaped a little different.
 
I never been in a slant that didnt have a 2.76 rear. That's saying I've been in only a few slants but they were all 2.76, except Raj's that had a ridiculous 'Doba 2.40ish rear gear. New oil, filters, coolant flush, roll of duct tape and drive it!
 
pishta said:
I never been in a slant that didnt have a 2.76 rear. That's saying I've been in only a few slants but they were all 2.76, except Raj's that had a ridiculous 'Doba 2.40ish rear gear. New oil, filters, coolant flush, roll of duct tape and drive it!
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I thought for SURE mine was a 2.94, but when I put it back in from having the 3.90 sure grip in it, there it was. A set of 3.23s. No wonder that little 170 was so peppy. lol
 
My 66 slant three-on-the-tree is a 3.23. Soon to be a 3.55 when I make that swap.
 
halfafish said:
My 66 slant three-on-the-tree is a 3.23. Soon to be a 3.55 when I make that swap.
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I'm goin the other way. This 9" has a 3.00 gear. I'm gonna use it when I swap in the T5.
 
I just drove from Memphis to Tucson non stop for the Duct Tape drags back in October. That was 24 hours and 30 minutes From Memphis to Tucson because of weather and traffic. The drive through Little rock sucked bad as I drove through it right at 4pm on a thursday afternoon. But on the way home I did it in 20 hours and 45min total time including fuel stops. Yes I accounted for the two hours for time zones. I was able to do this because I left AZ Sunday at 6am. I was going 80mph most of the way with 65-ish through Dallas. Set up is a 225/904 with a lock up converter, low ratio gears/ 2.76 gears/ 26.3" diameter tire. This is right at 2850 rpm for almost a day straight each way. Doorstep to doorstep is 1420 miles so that is an average on the way home of 68.43mph. Not bad for a 50 year old car.

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dart19666 said:
I just drove from Memphis to Tucson non stop for the Duct Tape drags back in October. That was 24 hours and 30 minutes From Memphis to Tucson because of weather and traffic. The drive through Little rock sucked bad as I drove through it right at 4pm on a thursday afternoon. But on the way home I did it in 20 hours and 45min total time including fuel stops. Yes I accounted for the two hours for time zones. I was able to do this because I left AZ Sunday at 6am. I was going 80mph most of the way with 65-ish through Dallas. Set up is a 225/904 with a lock up converter, low ratio gears/ 2.76 gears/ 26.3" diameter tire. This is right at 2850 rpm for almost a day straight each way. Doorstep to doorstep is 1420 miles so that is an average on the way home of 68.43mph. Not bad for a 50 year old car.

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Not too shabby at all!
 
pishta said:
I never been in a slant that didnt have a 2.76 rear. That's saying I've been in only a few slants but they were all 2.76, except Raj's that had a ridiculous 'Doba 2.40ish rear gear. New oil, filters, coolant flush, roll of duct tape and drive it!
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Almost all early-A 225's came with 2.94's & 13" tires..including both of My '64 GT's. The 'vert is a 3-on-the-tree, the Cpe is a PB auto.
My '69 Dart Custom 225 auto; 2.76's
My '72 Swinger 225 auto w/air; 2.76's
The '76 4-door w/discs & LBP 7.25; 2.76's
Early A's had smaller cams, the bump in cam size may have coincided with the drop in ratio, even tho' the cars were getting heavier as well.
 
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Once I get the new engine in to replace the 'naded one I'm hoping to do a 1,200 mile roadtrip in my 64 dart. I think I've got 3.23 gears so I gotta check that, hoping for 2.94s just for lower highway rpms. 25.2" tires. any advice?
 
I run a 27 inch tire and that’s already big back there 255 60 15. I think you should be fine, but if it’s cruise mileage your after make sure your timing and vacuum advance and in tune.
 
I paid a little closer to Vixen on her long drive this past weekend and she's doin better than I thought. At 72 MPH, she's turnin right at 3K and that's with 185/70 13s.
 
my brother got the best mileage out of his 76 Feather Duster (had 3 spd trans not OD) after the carb went to shyt and I had piece one together from 2 different 1945s/ the original and one from a '74. that was ear;y 80s, so I dont remember what was bad about the original, nor what pieces came from which carb. I just remember going to a junkyard and finding the only 1945 they had (small hole in the wall yard not many people knew about) and hoping I could do "something" with it. I was "just barely" driver license age at the time.
 
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Mine is a Jacobs, but I heard they went out of business. It includes an interpreter and an amp; to take the output from magnetic trigger inside the distributor, to fire a coil. Mine was new in the early 2000s
 
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AJ/FormS said:
Mine is a Jacobs, but I heard they went out of business. It includes an interpreter and an amp; to take the output from magnetic trigger inside the distributor, to fire a coil. Mine was new in the early 2000s
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Your tuning procedure seems to mention adding spark advance to see if the vehicle speed increases (due to increased efficiency/power/torque), yet you show a timing delay (retard) box. I googled, but couldn't find any sort of timing advance box that could be used with a stock distributor.
 
Yeah, I thought that might be confusing..... lol.
You cannot ADD timing to what the distributor is commanding.
You can only retard the timing, it and then restore it.
How you use this device is to install the device with the knob in the fully retarded position, start your engine, and reset your Power timing at the distributor, back to whatever your engine likes.
Now, you can take OUT retard with the knob, up to 12* in the case of this
device, by dialing in "advance" which is actually just anti-retarding/restoring it..
My timing curve is pretty much all bugged out. I have a manual trans. At 700rpm, the slowest I can drive is 5.12mph . The only ways to drive slower is ;
to ride the brake until the engine stalls, or
to ride the clutch until I kill the clutch, or
to retard the timing so it will idle slower.
The idle-timing is 14*, and so I set the knob on mine, which has a range of 15*, so that I can retard the Idle-Timing up to 9degrees, which, in gear and pulling the idle speed might go down to 550/500. At 500 the roadspeed is down to 3.66mph, which is walking speed.
But cruising on the hiway at 65=2140, the cruise timing is only 46*. The engine likes high 50s. I can give it another 5 on the dial-back, total 51* which is as good as it gets for local commuting.
For long distance cruising, I reset the knob and Power-timing to get me a max of UP TO 46+15=61*, but I lose the 9* Idle-retard feature.
 
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Jacobs was the hot ticket back in 2000. Some of the Crane stuff looks sorta like the Jacobs so I wonder if Crane bought them out? IDK
Back then MSD had a stand-alone unit as well. The last time I looked, maybe 5 years ago, just guessing, they still did. It looked a lil different than the pic I snagged off the Net.

HOWEVER
I took a quick look at the installation instructions. I'm NOT an electronics wizzard, but I see no reason that you couldn't cut off the MSD connector and splice the device into your factory Mopar electronic Ignition. I would call MSD and verify.
 
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OK, yeah, that makes more sense now. I did a similar test for optimum WOT timing on the road by connecting the distributor vacuum advance to a hand-held vacuum pump. I would add some vacuum, which added a known amount of advance, go WOT, then hit the vacuum release valve on the pump. If my acceleration decreased after releasing the vacuum, that meant that the engine liked the additional advance. If my acceleration increased after releasing the vacuum, that meant that the engine liked the original (base + mechanical) timing better.
Here are a couple good articles I found on distributor tuning.
More Power For Your Leaning Tower: Add 14-Horsepower To Your Slant 6 - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech
Gallery: Distributor Recurving for Improved Fuel Economy - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech
 
Great Idea! and cheap to implement.
That would work when the weight to power ratio is large. like with a slanty.
But at 400plus-hp, my 367 winds up so fast, and spins the tires so far, that I wouldn't be able to feel it at any legal roadspeed,lol.
 
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