I'm thinking I put too small a cam in my 360 Magnum...

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As to ring gaps yes, the Hypers gotta be right.
I installed mine by the book , and had nothing but heat troubles for about ten weeks. and Every time I shut her off I was in for a 10>15 minute wait, before the starter could wind her up again. I tried everything but couldn't get to the bottom of it.
So I took the engine down, loosened the skirt clearance, and opened the gaps up to the next bigger ring-factor, which, IIRC ended at .034 for the tops and for good measure, I open the Second gaps a few thou too.
And that was the end of overheating.
It had a trace of piston slap on cold mornings, so I installed a 195 stat which actually runs at 205 as measured by IR gun. By this time I had already installed a hi-flow Pump, Hi-flo stat, and had installed a Thermostatic clutch on the Biggest fan I could find. and the shroud had always been on there together with the cowl-seal and the top of the rad seal. My rad is an ancient one off a 1973 Dart with A/C; She's a 26 incher but still in the 22" core-opening. Even the patches on it have patches.
I never even look at the stock temp gauge any more.
Did I loose Power?
Hell no!
and when I had a double overdrive in her, I could cruise at any speed I dared to.

I gotta say, for me, the Hypers were the right pistons, and they now have over 125,000 miles on them, so they've done well. They are lightweight and the 360 neutral-revs like no other engine I've ever had. I think they were around 505gms
 
Brooks James said:
I was wondering, I was told that 225 were the best hope with upper arm offset bushings, I erred on the side of caution and got 215 even tho I did the offset bushings
Click to expand...
So are you saying that your front tires are 215s?
215 what. Nevermind it doesn't matter.
You need to think this thru.
Are you aware that your 360 with that cam, in your lightweight car, can be doing well over 60 mph in just 5 seconds of WOT. By Eight Seconds she'll be doing close to a hundred mph. And yur depending on 215s on the front and 235s on the back, to get you stopped; with one of the worst handling factory hotrods ever built by Mopar.
Brother, you better have great life insurance..........
SEVEN degrees off axis, and you cannot straighten that car out, Just Seven degrees and the back is coming around.
Even 235s on the front of my short WB Barracuda are not enough tire.
My secret weapon is the 295s on the back running no hydraulic proportioning at all on the back, and a very heavy rear brake bias. When I stomp the brakes, it's like I imagine it would feel like, to throw out a parachute!
If you pulled up to my front door with your Dart, and said "hop in", the first thing I'm gonna do, is to look at that combo of 215/235 and the second thing Ima gonna do, is say, "pass".
If I die/when I die, it's gonna be if I get stuck in the Tribulation, lol.

Ok Now, having said that, I also installed those problem solvers and got IIRC ~7 degrees castor on one side and maybe 6.5 on the other at Zero camber. By the time I got to 3/4* camber She was down to around 3* castor. So I gave back some camber to get some castor. I mighta ended up around 3.5* castor at or just under .5* camber.
Then I ordered some custom offset 5on4, 8x15" Rally wheels. IIRC those were 4.25 bs. And I worked my butt off to make them work. First the wheel weights rubbed, then the BJs were rubbing on the turns. My trusty disc-grinder got a workout that day I'll tell ya. Then when I backed off the Drive-on lift and simultaneously turned and braked, well then the fender got the rub. One by one I solved those problems to fit some sticky 245s....... which were great tires to have around town, but they didn't even last the summer, so back on went the 235s, and I learned to slow down.
The point is that 8x15s will fit up front with a 4" backspace. Should bolt right on.
However, Because the SAI is now in the wrong place, the tires tend to want to follow ruts in the road. So I switched to 7.5 wheels on Zero offset, and that did the trick.
I run the crap outta those 235/60-14 fronts, on those 7.5 x 14 zero offset wheels, with no issues whatsoever. and the bonus is that thy last for thousands of miles.
I just gotta slow down for the turns or, my favorite, steer with the rear tires sliding and on fire, lol.

Now; Mr. James, I apologize if I came off a lil harsh in the beginning, But my smartazzedness goes back 54 years to my first Mopar A-body. I have had at least one on the road for almost all of those years. I even crashed one on my wedding night! and yes, my new bride was in the other bucket.
These cars were never meant to handle 350 hp, never mind 400 or more, they were even lousy with the 275hp 340
At my age of 70 now, I have to depend on my car to not let me kill myself in it, cuz I ain't as quick as I once was.

For the street;
Those 215s have to go. If you need new wheels, well, welcome to HotRodding. I got a shed full of parts that just didn't make the grade.
and
you need to move the back springs over and put the tallest tires in there that will fit, with the widest-treads that will fit, with a minimum clearance to the body of 3/8 inch, and with a minimum of 1>1.25 inches of vertical clearance, depending on your springs and shocks. To the springs can be .25 inch or a hair less, depending on the amount of arch and the bushings used, and your driving style.
Get this done, before you ever drive it, cuz 350/400hp in a lightweight long wb Dart is a cunning recipe for disaster.
At your weight, I would definitely consider ballasting the side to side weight. As it is, if the alignment was set up NOT with you in it, then it will be DEAD WRONG when you climb into it. It will NEVER steer right, and it will eat tires. and you should look into heavier T-bars. I recommend 1.03s . and the 1/4m race track is gonna hate those; more nitrous!
I used to be an alignment guy, and I figured this out in a hurry.
Again, sorry if I aggravated you.

Thank you for your service.
 
Last edited:
AJ/FormS said:
So are you saying that your front tires are 215s?
215 what. Nevermind it doesn't matter.
You need to think this thru.
Are you aware that your 360 with that cam, in your lightweight car, can be doing well over 60 mph in just 5 seconds of WOT. By Eight Seconds she'll be doing close to a hundred mph. And yur depending on 215s on the front and 235s on the back, to get you stopped; with one of the worst handling factory hotrods ever built by Mopar.
Brother, you better have great life insurance..........
SEVEN degrees off axis, and you cannot straighten that car out, Just Seven degrees and the back is coming around.
Even 235s on the front of my short WB Barracuda are not enough tire.
My secret weapon is the 295s on the back running no hydraulic proportioning at all on the back, and a very heavy rear brake bias. When I stomp the brakes, it's like I imagine it would feel like, to throw out a parachute!
If you pulled up to my front door and said "hop in", the first thing I'm gonna do, is to look at that combo of 215/235 and the second thing Ima gonna do, is say, "pass".
If I die/when I die, it's gonna be if I get stuck in the Tribulation, lol.

Ok Now, having said that, I also installed those problem solvers and got IIRC ~7 degrees castor on one side and maybe 6.5 on the other at Zero camber. By the time I got to 3/4* camber She was down to around 3* castor. So I gave back some camber to get some castor. I mighta ended up around 3.5* castor at or just under .5* camber.
Then I ordered some custom offset 5on4, 8x15" Rally wheels. IIRC those were 4.25 bs. And I worked my butt off to make them work. First the wheel weights rubbed, then the BJs were rubbing on the turns. My trusty disc-grinder got a workout that day I'll tell ya. Then when I backed off the Drive-on lift and simultaneously turned and braked, well then the fender got the rub. One by one I solved those problems to fit some sticky 245s....... which were great tires to have around town, but they didn't even last the summer, so back on went the 235s, and I learned to slow down.
The point is that 8x15s will fit up front with a 4" backspace. Should bolt right on.
However, Because the SAI is now in the wrong place, the tires tend to want to follow ruts in the road. So I switched to 7.5 wheels on Zero offset, and that did the trick.
I run the crap outta those 235/60-14 fronts, on those 7.5 x 14 zero offset wheels, with no issues whatsoever. and the bonus is that thy last for thousands of miles.
I just gotta slow down for the turns or, my favorite, steer with the rear tires sliding and on fire, lol.

Now; Mr. James, I apologize if I came off a lil harsh in the beginning, But my smartazzedness goes back 54 years to my first Mopar A-body. I have had at least one on the road for almost all of those years. I even crashed one on my wedding night! and yes, my new bride was in the other bucket.
These cars were never meant to handle 350 hp, never mind 400 or more, they were even lousy with the 275hp 340
At my age of 70 now, I have to depend on my car to not let me kill myself in it, cuz I ain't as quick as I once was.

For the street;
Those 215s have to go. If you need new wheels, well, welcome to HotRodding. I got a shed full of parts that just didn't make the grade.
and
you need to move the back springs over and put the tallest tires in there that will fit, with the widest-treads that will fit, with a minimum clearance to the body of 3/8 inch, and with a minimum of 1>1.25 inches of vertical clearance, depending on your springs and shocks. To the springs can be .25 inch or a hair less, depending on the amount of arch and the bushings used, and your driving style.
Get this done, before you ever drive it, cuz 350/400hp in a lightweight long wb Dart is a recipe for disaster.
At your weight, I would definitely consider ballasting the side to side weight. As it is, if the alignment was set up NOT with you in it, then it will be DEAD WRONG when you climb into it. It will NEVER steer right, and it will eat tires. and you should look into heavier T-bars. I recommend 1.03s . and the 1/4m race track is gonna hate those; more nitrous!
I used to be an alignment guy, and I figured this out in a hurry.
Again, sorry if I aggravated you.

Thank you for your service.
Click to expand...
Good stuff, coming in a yr or so will be 15 Cragar SS wheels which will give me greater tire selection. Also Bilstein shocks.Have 1.03 bars now
 
@Brooks James
"Thanks, my springs are also the Hughes 1110"

IIRC,
the springs on my 367 are also Hughes 1110s, circa 2004.
And 5003 lifters, set at 1/2 turn preload. and the cam is
HE3038AL .549/.571 @ 1.6 adjustable-arms purchased from Mopar
I shimmed mine up a lil.
This set-up goes to 7200 with ease.

I missed a shift once, a long time ago, and saw the tach needle coming down past 8000.
I let the revs come down to ~3000, then slowly back to idle. BadaBoom all was good! Surprise surprise.
Right after that;
I installed a rev-limiter.......
and slick-shifted Second and Third gears, and
rebuilt my shifter, and
loc-tighted the external levers onto the studs.
After that, don't remember that I ever missed a shift again.

  • Installed Height/Pressure: 1.660"--120#
  • Pressure @ .450" lift: 280#
  • Pressure @ .500" lift: 303#
  • Pressure @ .550" lift: 327#
  • Coil Bind: @ .600" lift
  • Outer Spring ID/OD: 1.033"/1.440"
  • Type of Spring: Single w/Damper
 
Last edited:
Brooks James said:
I bought the cam from a guy who had worked for Crane in Miami.
The only specs I got were:
274/498 intake. 286/512
113 lsa, I bought it because of the Added duration for the 150 shot of Nitrous

He said it was an Old Crane Fireball grind.

Car is set up to cross the line at 6500

70Dart 3050 lbs, 3330 with my fat ***

Tires 25.2 diameter 23560R14

3.91 8 3/4

Doug's D452 1 5/8 headers

750 vac sec Holly, 50cc squirter

Chinese Air Gap

Stock block crank, rods, heads pistons (1110 Hughes spring kit)

3500 converter/reverse valve body

I calculated with the 150 shot I would be at 360 on the motor for a total
Of 510 hp. / 11:80-12:00 @110 mph


I'm concerned that the cam won't be sufficient when I put the MODMAN Indy Intake for Magnums on with the 2 Carter Competition Series 500's on
My back won't allow me to bend over much so I'll have to pay for camm installation, I have to get it right the first time !


????
Click to expand...
318willrun has two 4bbl on a mild 318 with stock stall and gear.
No saying yours will be optimal but you should be able to tune for functional at least.
 
@Brooks James
One of my friends thought he had a hot 340 .
His car is almost like mine, a 68, 4-speed street-Barracuda, except
his is an iron-headed 340, has a slightly bigger cam, a 2x4 tunnel ram, SS springs, and borrowed 4.30 gears (mine). It looks and sounds, pretty intimidating.
My car is an alloy-headed 360, 4-speed, Fresh-Air, 750DP/Air Gap/and has 3.55s.
We went to the same 1/8th-Mile track, on the same day, for a TnT.
I ran 4 times, with only one halfazzed complete run, with two mphs hovering around 93 mph, one run in which the timer did not work, and one run in which I missed a shift and just circled back. Afterwards, I went for some famously crappy track-lunch with my son, and we watched my friend flog his car.
Make no mistake, my friend had been tuning his combo for weeks and even borrowed my 4.30s for this event. His car hooked real nice. He worked tirelessly all morning to go no faster than 89.
My car was almost exactly as I drive it on the street. The only difference was, that I dropped the exhaust to get the weight down to 3457/me in it, which about matched his weight..
_____________________________________________

Carburetors are rated at a certain pressure differential. If an engine pulls harder than the differential, it will pull more cfm. If it pulls less than the differential, then it will pull fewer cfm. If a carb is rated in DRY Flow, it will not pull the same as one rated for WET flow.
If an engine can only pull 600 cfm, and already has a carb that can deliver that 600, then it will not make significantly more power with any arbitrarily chosen, larger-rated carb.

With as small a cam as you are considering, (274/286/113 IIRC) even a 750 is more carb than your engine needs.
(360 x 5500)/3456 = 574 ........... at 100% VE, which is what you are targeting to get 360 Hp NA..
Now rightaway somebody will jump on me saying; "everybody knows that formula doesn't work on Mopars".......... which is why we all put 750s on our Mopes........ cuz we all over estimate our lil SBMs.
Well no, the problem is that we all fail to recognize that
the formula is 100% accurate ,
and it is the ratings on the carbs that are not being matched, because most of our combos are sucking; low-density, hot, under-hood air, and not making the rated pressure differential, which most likely
was a dry rating anyway!

BTW,
A long time ago, I had a 276/286/110 cam ([email protected]), and in my alloy-headed [email protected]/1Scr, that combo was ferocious; and remains my all-time favorite combo. She was a real clutch-buster....... well actually she just busted everything behind her. One piece atta time she emptied my parts stash.
But in my combo, the powerband was long and wide and centered right around 5000. That is an awesome characteristic for a street engine,
but is NOT a particularly good racing cam.
Your chosen cam might be good for N2O, IDK anything about that stuff.

Happy HotRodding
 
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