360 does not seem to be making power and is slow in the 1/8. Need help and/or suggestions

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Where your converter stalls is a function of the torque your engine makes and if it doesn't make it then it cant use it. I've seen a change in converter make no difference in where it stalled.

Fix the tune and the converter should pick up rpm.
 
I get what you're saying. After talking to numerous car guys and racers, most if not everybody came up with the same general conclusion. The car needs more converter for the combo or, there's something wrong with the converter we have.Even a few of the converter companies we talked to said, with what we have, we needed to be up around at least a 4800 stall.I'm not saying that's the fix, I think there is multiple issues with the car.
 
One of the sprockets was a 1/2 tooth off from the other. So my first question is, which one's lying???
If you set the #1 piston at TDC and then checked the location of the dots of each sprocket then you’d know which one was closest to being at the 12 o’clock position, right?
 
Yes, you're right. That's why I went with the gear that I did. That's another thing that I've been dealing with on this car. Parts that are not right , even though they are"brand new"!!!
 
Yes, you're right. That's why I went with the gear that I did. That's another thing that I've been dealing with on this car. Parts that are not right , even though they are"brand new"!!!
That is exactly why you always degree a camshaft.
 
Assuming 24 tooth crank gear, each tooth would be 15°. Timing gear a half tooth off, and a sloppy chain retarding CAM timing maybe 10°, could easily turn a motor into a dog, especially one with an ignition problem.
 
KB107s came in at .012 below deck in my 360. and I used a .028 gasket for a Squish of .040 on closed chamber heads.
Open chamber heads will increase this beyond mattering.
I wonder if 38*of ignition timing is putting her into detonation. It should be on the plugs.
But you seem to have that covered.

As for the bottom-end, I'd put that on the 247/247/108* cam, AND mismatched compression ratio. That's a one-two punch. At 9.9Scr and 1000ft elevation, the Wallace puts your Altitude-Corrected Dcr at just 7.21 and your cranking cylinder pressure at 143 psi, with a piss-poor VP of 113, less than a stock smoggerteen.
There is your launch problem.
Unless your TC is pooched.

IMO; you need a lil less cam, and a lot more Scr.
I'll guess one camsize, still on a 108; and 10.5Scr. That'll get you an elevation corrected Dcr of 7.94 @162psi and a halfway decent VP of 1.33
To keep the 247* cam you would need to pump the Scr to 10.8, but the VP won't keep pace so the TC better be good. That 247 cam will want to be shifted at ABOUT 6000.
All numbers are for 91 gas minimum.
Ideally, if it was mine, I'd run a solid lifter cam to pick up the pressure at low rpm.

For comparison only,
My 360 pulled 93mph@3467pounds@930ft, with a 230*cam and 3.55s; with a 2.2 or more 60ft; allbeit with OOTB Eddie heads at 10.7 Scr. She runs 72/80s in the 750DP. The altitude-corrected Dcr on mine is 8.38, and VP of 149, which spins my 325/50-15DRs for hundreds of feet. Manual trans.
 
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KB107s came in at .012 below deck in my 360. and I used a .028 gasket for a Squish of .040 on closed chamber heads.
Open chamber heads will increase this beyond mattering.
I wonder if 38*of ignition timing is putting her into detonation. It should be on the plugs.
But you seem to have that covered.

As for the bottom-end, I'd put that on the 247/247/108* cam, AND mismatched compression ratio. That's a one-two punch. At 9.9Scr and 1000ft elevation, the Wallace puts your Altitude-Corrected Dcr at just 7.21 and your cranking cylinder pressure at 143 psi, with a piss-poor VP of 113, less than a stock smoggerteen.
There is your launch problem.
Unless your TC is pooched.

IMO; you need a lil less cam, and a lot more Scr.
I'll guess one camsize, still on a 108; and 10.5Scr. That'll get you an elevation corrected Dcr of 7.94 @162psi and a halfway decent VP of 1.33
To keep the 247* cam you would need to pump the Scr to 10.8, but the VP won't keep pace so the TC better be good. That 247 cam will want to be shifted at ABOUT 6000.
All numbers are for 91 gas minimum.
Ideally, if it was mine, I'd run a solid lifter cam to pick up the pressure at low rpm.

For comparison only,
My 360 pulled 93mph@3467pounds@930ft, with a 230*cam and 3.55s; with a 2.2 or more 60ft; allbeit with OOTB Eddie heads at 10.7 Scr. She runs 72/80s in the 750DP. The altitude-corrected Dcr on mine is 8.38, and VP of 149, which spins my 325/50-15DRs for hundreds of feet. Manual trans.

VP?
 
Thanks for the input A/J. We were originally going to use the 284/484 Mopar cam but, the shop that was doing our motor said to use the one we have now. It's basically a copy 0f the 292/509, Bullet cam. I know that cam wants compression to work. Now I wonder if sticking with the other cam would have been better.
 
Thanks for the input A/J. We were originally going to use the 284/484 Mopar cam but, the shop that was doing our motor said to use the one we have now. It's basically a copy 0f the 292/509, Bullet cam. I know that cam wants compression to work. Now I wonder if sticking with the other cam would have been better.

once you get the car to where there are no gremlins, you are gonna find the cam will be fine..... if its paired with a good convertor.
I just ran a stock stroke 360 the last 4 years. Maybe 10 to 1.
Pretty much stock eddie heads, airgap, 950 Holley, Dougs headers...260/264 flat tappet...but 8 inch 5k flash vert...
3310 or so with me in it... ran as good as 11.20’s... 7 teens in 1/8
If you want to go fast, gotta have a suitable convertor
 
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In my streeter, I ran that 292/292/108 Mopar for one summer, and couldn't get rid of it fast enough. It was not happy with the 3.55s I was trying to make work. Even at 11.3Scr with OOTB Eddies, and a clutch, I was not impressed with the bottom end. At 9.9 I can't see the bottom end as anything but disappointing. The Rs need to get up around 3500 before that 292 wakes up, and she doesn't pull hard until over 5000. I Revved mine out to 7000 before I could tell it was sliding down the back of the curve.
During the engine planning stage, I had anticipated this, and built to an Scr that I was pretty sure was adjustable enough to work with less cam, so after I pulled it, in went a 223@ .050 which was infinity more friendly to my 3.55s. After that cam died I switched to a [email protected], which gave up a lotta bottom end to get only a lil topend. All three cams had the compression adjusted to run right around 180psi, and the Q to run in the low to mid .030s .. As I said, in a manual-trans streeter. None of these had problems with bottom-end, lol.
When the Wallace Calculator came on line, I ran all three combos thru it and the V/P numbers helped me understand what I was feeling behind the wheel. I cannot vouch for their ultmate accuracy, but in my experience the numbers mirror my feelings.
Read about V/P here;
V/P Index Calculation

BTW
Because I had so much Scr to play with, I moved that Mopar 292/108
from 4advanced to 8advanced, to 4retarded, and finally to 2advanced,
where I thought it did about the best. But in none of it's travels did that cam like my 3.55s. It was fine with 4.30s, but there was no way I was gonna run them full-time. That was a very busy summer.
 
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In my streeter, I ran that 292/292/108 Mopar for one summer, and couldn't get rid of it fast enough. It was not happy with the 3.55s I was trying to make work. Even at 11.3Scr with OOTB Eddies, and a clutch, I was not impressed with the bottom end. At 9.9 I can't see the bottom end as anything but disappointing. The Rs need to get up around 3500 before that 292 wakes up, and she doesn't pull hard until over 5000. I Revved mine out to 7000 before I could tell it was sliding down the back of the curve.
During the engine planning stage, I had anticipated this, and built to an Scr that I was pretty sure was adjustable enough to work with less cam, so after I pulled it, in went a 223@ .050 which was infinity more friendly to my 3.55s. After that cam died I switched to a [email protected], which gave up a lotta bottom end to get only a lil topend. All three cams had the compression adjusted to run right around 180psi, and the Q to run in the low to mid .030s .. As I said, in a manual-trans streeter. None of these had problems with bottom-end, lol.
When the Wallace Calculator came on line, I ran all three combos thru it and the V/P numbers helped me understand what I was feeling behind the wheel. I cannot vouch for their ultmate accuracy, but in my experience the numbers mirror my feelings.
Read about V/P here;
V/P Index Calculation

BTW
Because I had so much Scr to play with, I moved that Mopar 292/108
from 4advanced to 8advanced, to 4retarded, and finally to 2advanced,
where I thought it did about the best. But in none of it's travels did that cam like my 3.55s. It was fine with 4.30s, but there was no way I was gonna run them full-time. That was a very busy summer.

Thank for that.
have seen this before but didn't take the time to read all the way to the bottom were they talk about the V/P index.
Haven't grasp it 100% but will read it a few more times.
Thanks AJ.
 
VP in a racecar counts for not much, because you can get past the soft part with stall.
On the street tho;
With an automatic, IDK cuz I don't have a soft automatic combo. My 318 car has a 2800TC and by the time I get a few feet out, the engine is winding up pretty good. If the tires slip she's acooking.
But with a manual trans, VP is a really really big deal,cuz there is No fluid coupling and No Torque Multiplication; the tires are married to the engine. So, in day to day operation, that manual-trans car will spend something like 95% of it's time below 3000rpm, in the thick of the soft zone, not to mention every single time you start off from zero mph.
This is even important to average fuel economy around town, because without a decent VP number, you will always be driving deeper into the carb than you want to be; and so burning up the gas. Combine that with a lack of ignition advance and you got yourself a gashog.

My combo has had a VP as high as 164@1000ft elevation, which I really really enjoyed. But with the later ICA of this last cam, it fell to ~149 and I can tell you that I was sorely disappointed. I finally broke down and swapped out my 2.66 low gearset for a 3.09 gearset, which cured the take off blues. And then, once into second gear up at 3000rpm, it wasn't that noticeable anymore and eventually I forgot about it.
IMO, in a streeter with a starter-gear of 9.44 or less, she will need lots of VP. I could never be satisfied down at 124 or less, which is like a 5.2M. Nor even 135. The 149 of my combo is only acceptable because the 295/50-15 BFGs spin right away, and the 10.97 starter-gear.
A high VP can come in handy at certain low-rpm passing situations, cuz you can downshift only one gear instead of two. Sometimes going down two gears is kindof a waste cuz you gotta upshift almost right away.
 
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If my car was a daily.....I might care..........a little....................
I also thing it would help if you were going to change your camshaft instead of your converter.
In the end i'm still going to count on my cam company and or builder to to choose the best cam for me. I have never claimed to be that smart/educated to do that. However understanding more pieces of the puzzle, i'm all EARS!!!:D
 
My 2 cents the distributor, it has to be full advance at 6-800 to leave. My Duster with a a383 and stock street Hemi converter with 4.88 gears would do 1.65 60 run 7.35 eighth and 11.60 in the quarter. Work on the carb too, idle circuits are probably lean as he!! with that cam, close the air and open up the fuel bleeds. You’re getting those results with stock stuff.
 
Thanks for the input A/J. We were originally going to use the 284/484 Mopar cam but, the shop that was doing our motor said to use the one we have now. It's basically a copy 0f the 292/509, Bullet cam. I know that cam wants compression to work. Now I wonder if sticking with the other cam would have been better.
Lots of ppl like the 509 cam. I never use/recommend it unless u have at least 12-1 compression. Ive seen so many disappointed ppl. Kim
 
VP in a racecar counts for not much, because you can get past the soft part with stall.
On the street tho;
With an automatic, IDK cuz I don't have a soft automatic combo. My 318 car has a 2800TC and by the time I get a few feet out, the engine is winding up pretty good. If the tires slip she's acooking.
But with a manual trans, VP is a really really big deal,cuz there is No fluid coupling and No Torque Multiplication; the tires are married to the engine. So, in day to day operation, that manual-trans car will spend something like 95% of it's time below 3000rpm, in the thick of the soft zone, not to mention every single time you start off from zero mph.
This is even important to average fuel economy around town, because without a decent VP number, you will always be driving deeper into the carb than you want to be; and so burning up the gas. Combine that with a lack of ignition advance and you got yourself a gashog.

My combo has had a VP as high as 164@1000ft elevation, which I really really enjoyed. But with the later ICA of this last cam, it fell to ~149 and I can tell you that I was sorely disappointed. I finally broke down and swapped out my 2.66 low gearset for a 3.09 gearset, which cured the take off blues. And then, once into second gear up at 3000rpm, it wasn't that noticeable anymore and eventually I forgot about it.
IMO, in a streeter with a starter-gear of 9.44 or less, she will need lots of VP. I could never be satisfied down at 124 or less, which is like a 5.2M. Nor even 135. The 149 of my combo is only acceptable because the 295/50-15 BFGs spin right away, and the 10.97 starter-gear.
A high VP can come in handy at certain low-rpm passing situations, cuz you can downshift only one gear instead of two. Sometimes going down two gears is kindof a waste cuz you gotta upshift almost right away.
Not to highjack the op but, AJ do you know why the V/P for the 340 example on the Wallace site is 269, but when you run the specs on their 340 example through their dynamic calc you get 124?
 
because 10.5:1 compression.........in the real world is only 9.4:1
AJ can go deeper into it, but that is part of it.
 
Not to highjack the op but, AJ do you know why the V/P for the 340 example on the Wallace site is 269, but when you run the specs on their 340 example through their dynamic calc you get 124?
Probably you entered the wrong Ica,
you have to figure from the advertised specs, NOT the .050s..
VP of 124 is closer to the truth with the stock specs, depending on your ICL.
At sealevel;
340 w/10.5 and Ica of 66* I get 131
340 w/10/1 ..........made about 124
the early 318s .......made about 136
the 8/1 318s ... come in around 116
the 8/1 360s .. come in around 126
the 5.2M .....IIRC is also around 124

Anybody who grew up with an early 318 remembers how peppy they were, and how doggy the 360s seemed to be. Nobody ever bragged on the 340s bottom end, even tho they never came with less than 3.23s. The VPs reflect that very well.

Don't forget to enter your elevation, to get your corrected Dcr.
All my own three builds were to the corrected Dcr, and all three worked excellently.
I bet a guy could make a spreadsheet relating corrected Dcr to stall/starter gear and never make a bad call.

hang on!
You mean in the VP article right?
V/P Index Calculation
That has to be an error; If I run their numbers thru the calculator until the effective stroke and pressures match and then I get; ohboy more errors, so something is screwed up in the article.
To get an effective stroke of 2.52 the Ica has to be 66*, so they got part that right. But there is no way to fudge the pressures into line unless you supercharge it, so somebody goofed. I can get to 173.49psi using 10.7Scr, but the VP only makes 135
Here is my best fudging;
With their numbers alongside in ()
Static compression ratio of.................... 10.7:1. ...........(10/1)
Ica of 66* @ sealevel
Effective stroke is..................................... 2.52 inches.........(same)
Your dynamic compression ratio is ............. 8.37:1 ...............(7.84)
Your dynamic cranking pressure is ..............173.49 PSI..........(same)
Your effective boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of PSI is 8.37 :1.
V/P (Volume to Pressure Index)............... is 135 ................. (269)
interestingly, 135 is half of 269

Good catch on your part.
Whatever they are doing, it carries on in the article, so you can still get useful information out of it by comparing the results to eachother.
If I had to guess, I'd say they are working with absolute pressures....
Yeah that's it. Here are the numbers at 10/1;sealevel, and gauge pressure
Static compression ratio of .................... 10.:1...................(same)
Effective stroke is ......................................2.52 inches.......... (same)
Your dynamic compression ratio is .............. 7.84:1 ................ (same)
Your dynamic cranking pressure is .............. 159.28 PSI.......... (173ab)
Your effective boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of PSI is 7.84 :1.
V/P (Volume to Pressure Index) ................. is 123 ..................(269)
but the VP is still goofy, so


Volume/Pressure Index
V/P = CP × VE × N × .3% (.3% or .003 is a correction factor to return a useful 2 digit number roughly proportionate to torque)
where;
CP is pressure absolute (177 in this case)
VE is effective cylinder volume (258.4 in this case)
N is number of cylinders (8)
So
177 x258.4 x8 =1097.68/ nah,still doesn't work, so

IDK what they are doing. I cannot fudge their 269 into the calculator's 123 no matter how I fudge their formula, in the thought that they mighta put a wrong operational sign in there.
I tried...........

But IMO, it really doesn't matter. If you only use the Calculator, you will always get a useful number to use for comparison.
And if you look closely at how the formula is set up, you can see that it works equally with any sized engine. So you can assume a 408 stroker with a VP of 145 is gonna act just like a 367 at 145........... up to somewhere between 3000 and close to peak torque. In terms of VP, 145 is down-build for a 408, and 145 is an up-build for a 360. But in this case up is down and down is up, the 408 will use a large cam, and the 367 will need tons of pressure and a smallish cam. So once they are performing at par, car for car, (in the range of 3000 to say 3800), the 408 will begin to run away on the 367. You get the idea.
This is also why a dragracer doesn't need to care about VP, because he is launching close to peak torque, and the rpm will never dip down that far again.

But for a streeter,
big VP means taking off like a good BB, and/or using small gears and short stalls.
BTW; a 68 440Magnum has a VP around 137, by the numbers. So I remember those, and I liked them, so 137 is always and ever will be, my minimum target. You can get a 318LA up to there but it'll cost you, and it won't be all that powerful until the Dcr goes thru the roof, past pumpgas. But it will sure be snappy down low. IMO, for a small-geared streeter, 137ish is where the fun starts.
Since you can compare VPs of any engine directly, that means you can also get an idea of what gears to run.
For instance, a VP of 137 with a starter gear of 10/1 will be daymn snappy off the line no matter what the engine-size. So that would be; 137vp x10 gear=1370 factor.
So if your combo only makes 124VP, it will need 1370/124=11/1 starter-gear to take off similarly. But if your combo makes 160, then 1370/160=8.56 starter gear. With a 4 speed and a 2.66 low gear, this is the difference from 4.72s to 4.29s to 3.67s
And

with a VP of ~153, my combo can run 1370/153= a starter of 8.95; which with a 2.33 low is 3.84s.. But I run a 3.09 low, so I could run down to 2.90s. I chose 3.55s cuz I have a .78 overdrive, giving it a final drive of 2.77 on the hiway. Cool, hey!
With a starter of 3.09 x3.55=10.97, it takes off like a 10.97/2.33=4.71s; yes she's a dump it and go deal with the factory flywheel.
But I digress; I know at least three or four guys, who are falling asleep.
zzzzzzzzzzzzzzzzzzzzzzzzzzzz
 
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Probably you entered the wrong Ica, you have to figure from the advertised specs, NOT the .050s
124 is closer to the truth with the stock specs
Don't forget to enter your elevation, to get your corrected Dcr.
Actually, if you go to the Dynamic calc page, there’s a ‘V/P Index Calculation’ icon below the fill in boxes, click that and go way down the page and below a chart is ‘their’ 340 example at 269 V/P. I used ‘their’ ICA, comp, etc.
 
AJ/FormS Ok thanks, a typo, that’s what I was wondering. ‘Now back to our regularly scheduled thread’ lol
 
Not a typo; they are working with absolute pressure, instead of gauge pressure.

Oh I just figured it out,lol;

They are using 258.4 CUBIC INCHES FOR ALL CYLINDERS so;
177 x 258.4 x .003= 137vp
Crap, still not 269; I give up.
 
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Like Hillary said “what difference does it make”
 
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