How to determine the RPM for all in?

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67dartgtgo

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Hi gang, clearances measured good and new cam installed, broken in and running good when not under any load. I’m not able to take it for a test drive yet but want to see what you guys think about my timing for the application to get it close.
Specs:
5.9 Magnum
Stock heads
Hugh’s camshaft 1418aln10 214/[email protected] on 110 lobe separation
Air gap intake
727
3:55 sure grip
275/50/15’s....about 26” diameter
I have a fire core distributor with a one light and one medium spring.
Runs great with no load.
I have the initial at 20* and final mechanical at 32* but it’s in by 1900 rpm.
Seems way early. My next move is to go to the 2 medium springs.
Thoughts?
 
Thats a bit too fast should have it all in by 3000 rpm. Try one heavy one medium spring should get you there, thats what i am running.
 
Hi gang, clearances measured good and new cam installed, broken in and running good when not under any load. I’m not able to take it for a test drive yet but want to see what you guys think about my timing for the application to get it close.
Specs:
5.9 Magnum
Stock heads
Hugh’s camshaft 1418aln10 214/[email protected] on 110 lobe separation
Air gap intake
727
3:55 sure grip
275/50/15’s....about 26” diameter
I have a fire core distributor with a one light and one medium spring.
Runs great with no load.
I have the initial at 20* and final mechanical at 32* but it’s in by 1900 rpm.
Seems way early. My next move is to go to the 2 medium springs.
Thoughts?



If it doesn't rattle leave it alone. Back in the day when I ran points I took the springs off and let the point drag close the weights so it would start.

Early timing doesn't hurt as long as it isn't rattling.
 
Back in the day when I ran points I took the springs off and let the point drag close the weights so it would start.

!!LOL!! I ran that way for awhile. The old 70RR, Sig Erson, Holley 800dp, used Prestolite tach drive hemi dist, and Accel points. For "awhile" I used a Tiger/ Delta CD box. This was in the '70RR. Had a great big Jones-Motrola tach mounted behind the tach/ clock cutout in the dash. "Nearly" matched the speedo
 
!!LOL!! I ran that way for awhile. The old 70RR, Sig Erson, Holley 800dp, used Prestolite tach drive hemi dist, and Accel points. For "awhile" I used a Tiger/ Delta CD box. This was in the '70RR. Had a great big Jones-Motrola tach mounted behind the tach/ clock cutout in the dash. "Nearly" matched the speedo



We are seriously old. Damn.
 
We are LOL. I'll be the big seven oh in June Not sure that's a great milestone LOL
 
With an automatic, you can get away with chit. But get your T-port sync set first, then let your idle timing determine your idle-speed, without changing the speed screw.
If the car seems kinda jumpy with the timing all in so early, then slow it down some.
If the choke doesn't work right,with the vacuum advance plumbed to the spark-port try a little less idle-timing.(See note I, below)
Sometimes slowing the All-in down, to in the range of 3200 to 3600,will allow the engine to run the next lower grade of gas.Yes you will lose a few horsepower, below that, But your combo is way too heavy on low-rpm torque already,lol, and you'll never miss it,
and you only go through that zone once at WOT, on the way to somewhere else.
At Part Throttle, you won't notice it either, cuz if you need a few more hp you just drive a little deeper into the throttle.
________________________________________________
note1
Why less. Well if you have a lot of idle timing then the T-valves will be nearly closed at idle, (see note2). And so, on the fast-idle step, the sparkport will not be engaged, and the engine will have to warm up on the Idle-timing only, with a couple of centrifugal. So in your case 20 +say 4=24. But the cold engine might like 40 or more. I used to be able to get Vcans from about 9 to 22. So to solve the on-choke problem you could run say 14 Idle plus 4 Centrifugal, plus up to 22 in the can for a total of 40*,imagine that. This would allow you to slow the fast-idle down to the lowest rpm that will keep the sparkport alive.
Note2
sometimes so far closed that the engine will want to stall when the throttle is abruptly closed.
Note3
My 367 with a 223* cam, ran 14idle/28@2800/34@3400/+22VA. With aluminum heads it ran a 10.9Scr on 87E10. Since it spun 295s to over 60mph, I didn't miss a few foot-pounds below 3000rpm. And over 100,000 miles I saved a lot of coin, not buying top-grade fuel.
EDIT:
To run the 2-stage curve, I had to grind a buncha metal off my flyweights. My spring selection was very limited. I ended up with several sets of different weight,weights; as well as several different cams; some with modded slots.
To make all this, fun, I got rid of that annoying clip at the top of the driveshaft. Instead, I drilled and tapped it to receive a tiny machine screw. Then I rooted around my junk drawer and found just the right spacer to put under it to keep the cam from walking up the shaft. This made changing the curve a breeze.
I also set my power-timing a couple of degrees shy of what might be considered optimum.My little 367 makes gobs of torque, and with my TM (Torque Multiplication), I don't need every last bit, so again, 87E10 for the win. I think I ran close to or over 190psi (10.9Scr),.......with a [email protected] cam,..............still on 87E10.
 
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My advice is to bring it all in at your convertor stall speed and then work down from there if you want it faster. If it acts up starting run a 20 degree start retard, don't pull the bas timing back.
 
No vacuum advance, you can run like that, just like the "old guys" said. Especially if this is mostly for racing. You may find some retard at higher rpm - it depends on how fast the electronics are and/or if they built compensation into the box. In that case you'll have to slow down the curve so it doesn't appear to lose advance before shift rpm.
 
This is mostly street driven with a few track passes now and then for fun.
Definitely going to slow down the curve some by installing the second medium spring and try it.
Right now initial 20, final 32, with vacuum 36 but in way early I think.
Going to try to bring it all in at the tc stall 2500 or close and go from there per roccodart’s advice. Hey...I love making changes for the better. I guess I won’t really know how well it is for sure until I can get it out under load and these snow storms up here aren’t helping...lol
 
What do you mean,"with vacuum 36"?

Vacuum timing is never part of the power-timing, cuz when at WOT, the vacuum falls to below the level at which the Vcan will come alive. And it's never included in the "all-in" figure. You can include it like this 20/32 +4
But if you are slowly reving it to 2200ish, and seeing just 36*...32* of which are mechanical,, that means the vacuum is only 4*. That is not nearly enough for a 214/218 cam in a combo like yours, if it was properly set up. However, with your mechanical so fast, I wouldn't change it until you settle the all-in rpm
 
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Like AJ wrote, if you're going to make use of vacuum advance, its a different story.
Set the vac advance up for the light throttle cruising rpm and vacuum. Do that after establishing the WOT timing.
If you got nothing else, you can start with Chrysler's guidelines.
This from Mopar Performance DCF-194. If you check out the timing of factory combos, the vac advance + timing at 60mph cruise rpms works out pretty much the same ballpark, something around 50-54*

Timing_Page_Mopar_Performance_Instruction.jpg
 
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AJ....damn...I was totally screwed up. That makes all the sense in the world.
Sometimes I’m not so bright. Thank you both.
Mattax...I wish had that guideline to begin with.
You guys are making me smart in my old age.
 
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67dartgtgo, if your going to use the vacuum advance, for cruising, limit the total timing to 52*’s until you know what it can handle and like.

Until then, that chart is a good base to start with. AJ’s gotcha good.
 
We are LOL. I'll be the big seven oh in June Not sure that's a great milestone LOL
I`ll be 72 in Oct. , Almost all mwah friends have already gone! Never did have a bunch tho! Hang in there, u can start bragging about it !! LOL
 
If it doesn't rattle leave it alone. Back in the day when I ran points I took the springs off and let the point drag close the weights so it would start.

Early timing doesn't hurt as long as it isn't rattling.
True that. Unless you are class racing and need to squeeze every last horse out of that Magnum, as long as it doesn't ping and runs good I wouldn't mess with it. Unless you like to mess with that stuff. You can dink with it and may-be go the wrong direction and will have to go through the work to change it all back.
 
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This is mostly street driven with a few track passes now and then for fun.
Definitely going to slow down the curve some by installing the second medium spring and try it.
Right now initial 20, final 32, with vacuum 36 but in way early I think.
Going to try to bring it all in at the tc stall 2500 or close and go from there per roccodart’s advice. Hey...I love making changes for the better. I guess I won’t really know how well it is for sure until I can get it out under load and these snow storms up here aren’t helping...lol

IF you have a 2500 convertor I'd bring it al in by then and be done with it. NO reason to have it come in faster than that
 
My two cents. Back in 1968, ran my '68 cuda BB with no vacuum advance (locked out) and full advance at 2000 RPM. It ran great. Got 7mpg.
 
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