New to fabo, 73 dart 360 help

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Cumminsil6

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I apologize if this topic has been covered already, I am new to this website and haven't got the hang of it yet. I have a 73 dart with a built up 360 in it. 360 block, decked, bored 30 over, speed pro flat tops, floated rods, ported j heads, Manley stainless 2.02 1.60 valves, dual comp springs, comp 292h cam, edelbrock torker intake, quick fuel ss750 carb. Trying to figure out where my timing needs to be, and rather or not my distributor needs curved. Pentronix ready to run setup. Motor just seems like it dosent have that much power, won't even squeal the tires into 2nd gear and dosent seem to run any better than my old motor with less work done to it
 
What kind of torque converter is behind that cam that specifically states it requires a 3000 stall speed?

Hydraulic-Serious Street / Strip effort.9.5:1 to 10.5:1 comp. Aftermarket manifold, headers & 3.91 gear. 3000-3500 stall in automatic cars.
 
What kind of torque converter is behind that cam that specifically states it requires a 3000 stall speed?

Hydraulic-Serious Street / Strip effort.9.5:1 to 10.5:1 comp. Aftermarket manifold, headers & 3.91 gear. 3000-3500 stall in automatic cars.
Yeah bud it has a fairbanks 10" 3200 stall in it with a 3.91 sure grip center section
 
HaH, welcome to the big-cam world.
You can throw all the timing in there you like it will not solve the problem.
I ran that 292cam in my 360 at 11.3 Scr, and I had a clutch, and I got rid of that thing just as fast as I could.
Rusty may be along shortly and offer a new cam ICL of 100*, but that made very little difference in my engine. I suspect my 11.3 Scr had something to do with that.
So; if you know your ICL let us know. How far down in the hole are your pistons and did you cc your heads? Perhaps you know your compression ratio? What gears are you running? please don't say less than 3.91s,lol.

That cam makes very poor low-rpm torque, I think less than a stock teener.It doesn't make it's power until way up the rpm band say from 5000 to 6500 with factory heads. IMO it is not a street-friendly cam for a stick car, and even less so for an auto.
Did you catch that: I ran a Compression ratio of 11.3 with aluminum heads.
With iron you will need at least 10.8
#1)Heres what that would look like
Static compression ratio of 10.8:1.
Effective stroke is 2.64 inches.
Your dynamic compression ratio is 8.23:1 .
Your dynamic cranking pressure is 165.87 PSI.
V/P (Volume to Pressure Index) is 134.........................................134VP
With a 3200stall the VP won't mean much to you. But that 165 psi is pretty important, and it will need a very special timing curve. To stay out of detonation, she will also need a tight Quench.
#2) With stock uncut heads and pistons down in the hole your compression ratio could be as low as 8.7, and this is what that would look like.
Static compression ratio of 8.7:1.
Effective stroke is 2.64 inches.
Your dynamic compression ratio is 6.68:1 .
Your dynamic cranking pressure is 126.16 PSI.
V/P (Volume to Pressure Index) is 102...................................................102VP
Now, this here 126psi is a total dog off the line, and it sucks gas big-time. Once you get it wound up to 5000 it will wake up but it's gonna need help from the headers, the rear gears,and the tune.
#3) Now here is what a stock 318would look like
Static compression ratio of 7.8:1.
Effective stroke is 2.89 inches.
Your dynamic compression ratio is 6.93:1 .
Your dynamic cranking pressure is 132.46 PSI.
V/P (Volume to Pressure Index) is 110..................................................110VP
Notice the teener is running a higher Dcr and more cylinder pressure. Also notice the VPs now. The teener VP is 110/102=7.8% higher than yours might be. If you didn't have the 3200, You'd be one very unhappy camper.
#4) Here's the stock 360
Static compression ratio of 8.0:1.
Effective stroke is 3.02 inches.
Your dynamic compression ratio is 6.91:1 .
Your dynamic cranking pressure is 131.95 PSI.
V/P (Volume to Pressure Index) is 120..............................................120VP
Notice that it too is making a higher Dcr and more cylinder pressure, and it's VP is 120/102= Plus 17.6% more low-rpm performance.Again the VP is not relevant much to you, but is included for comparison.

Ok so now that you know what's going on the next thing you need to do is go measure your cylinder pressure to see how bad it really is.
Then;
Get you some headers and a free-flowing exhaust.
Plus you'll need to kick that Torquer single plain to the curb
And get at least 3.91s

Or you could save yourself a lot of time and money, and throw that cam away like I did. Actually, I got lucky and sold it to a dedicated racer.But saying I threw it away carries more impact, and it is exactly what I wouldda done if the Racer-guy hadn't expressed an interest in it. She was already out and taking up shelf-space.

Now I'll tell you something else; In my combo, I did get that stinking 292 to wake up, but it needed quite a bit of Rs to get the tires churning, but once it broke them loose it was rubber to 60 mph and more with 245s.lol. The part that disappointed me was that when driving around normally, it was like driving a sick 318. 3.55s made it a total dog. So I got me a 3.09od box, which improved the take off 16%. But then second gear became a dog gear cuz I lost 14% there. With the od, I then switched to 3.91s and eventually 4.30s. With a 21% across-the-board improvement over 3.55s,those 4.30s were the magic number. But that od box wasn't working either. The splits were just too far apart for that cam.
And so are the automatic ratios. To get second just right, you need to run too much starter gear. The 2-3 ain't quite so bad. But I can't see that cam working in a street auto, cuz to get second right is gonna take a lotta starter gear, and then you can't run it on the hiway. To be effective in second will require at least 3200rpm at 30 mph. This will take a rear gear of 5.92lol, so that's not gonna work.
So that leaves you with having to downshift. So to get 3200 at 30 in first will take 3.30 gears, and you can cruize these at about 2000 in second so that WILL work. Except with 3.30s,you won't have decent torque with that cam to blast off with. Nor with 3.55s. nor probably with 3.73s.
But say you had 3.91s and 26.5" tires . These will get you about 3650rpm in first/2160 in second at 30mph. Yeah that might work, if you had decent cylinder pressure. With an automatic, and it's off-the-line TM, Ima thinking the 3.91s might have worked for me, but I'm not an auto kindof guy.

Ok so, I offer no solution until the compression results are in, except no amount of timing is gonna get you outta this hole
You can read about VP here:
V/P Index Calculation
 
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Depending on the Speed Pro piston used the CR may not be anywhere near what's thought.
 
Ok so what I did was back-engineer the factory 360 to 105cc total chamber volume, to get 8.0 Scr.
He's got 2.02 J-heads so thats a wash, I called 'em 72cc. The factory gaskets were probably .028s, so say 6.4cc The factory pistons were dished; So this maths out to
105-(72+6.4) =26.6 in the deck and dome. I called it 10.3cc in .050 down and the rest in the dish,so 16.3 which seemed reasonable to me.

So then with a .030 overbore I recalculated the swept from 737cc to 748.3
I took a leap that OP decked .010 off the top, and so that leaves 9.3 in the deck clearance. And the head is still 72 and the gasket now 8.9, plus 5 in the eyebrows. Sooo, that maths out to a total chamber volume of 95.2.
I arbitrarily added 2cc to this for a total of 97.2, and the Scr thus comes to (748.3+97.2)/97.2 =8.7
Then I entered that into the Wallace so as to make a worst case.
And then I built a house of cards on that, for illustrative purposes.
 
Ok so what I did was back-engineer the factory 360 to 105cc total chamber volume, to get 8.0 Scr.
He's got 2.02 J-heads so thats a wash, I called 'em 72cc. The factory gaskets were probably .028s, so say 6.4cc The factory pistons were dished; So this maths out to
105-(72+6.4) =26.6 in the deck and dome. I called it 10.3cc in .050 down and the rest in the dish,so 16.3 which seemed reasonable to me.

So then with a .030 overbore I recalculated the swept from 737cc to 748.3
I took a leap that OP decked .010 off the top, and so that leaves 9.3 in the deck clearance. And the head is still 72 and the gasket now 8.9, plus 5 in the eyebrows. Sooo, that maths out to a total chamber volume of 95.2.
I arbitrarily added 2cc to this for a total of 97.2, and the Scr thus comes to (748.3+97.2)/97.2 =8.7
Then I entered that into the Wallace so as to make a worst case.
And then I built a house of cards on that, for illustrative purposes.
LOL, where's all the numbers?
 
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