If you start the pull at 2000 that's about all the better it gets. If it makes 100 horse and 150 torque that's what you have at cruising speed. Whats it take to power a 3000# car to 55 mph? 50 horse or less?
Good Cam for 318
- Thread starter xactorocker
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Rat Bastid
Dunamis Metron
That’s what I’m saying Mike. You don’t test at part throttle.
Who drives at WOT at 2000 RPM? No one certainly cruises at 2000 RPM at WOT.
Thats not what these types of engine dyno’s are for. The OEM’s have dyno’s that can test that type of thing but the average shop can’t afford the millions of dollars it takes to buy and equip a dyno like that.
You can set the dyno to part throttle at 2000 RPM and use the trace record feature (on Performance Trends software) and test for ignition timing, emulsion and some other things, but you don’t cruise at WOT.
The question above is why don’t they start the pulls down at 2000 RPM and I gave a somewhat detailed answer as to why it isn’t done.
The “no matter what certain to make a performance improvement in a high geared low compression 318.” Works well with any of the 318 port intakes.
Mile-A-Mor Cam [3901M] - $246.00 : ISKY Racing Cams, Do It Right
Mile-A-Mor Cam [3901M] - $246.00 : ISKY Racing Cams, Do It Right
Mainly because in a full throttle run aka drag, 0-60 etc... lowest rpm don't matter much even with stock gearing and stall you don't spend much time down there.
And as for normal driving does a full throttle run on a dyno show us anything? I know Richard Holdener did a half throttle dyno pull and it made about 75% the hp and curve was similar to full throttle so it may.
But also at normal driving your hp requirement is so low something like 1-30hp even a /6 makes more than needed. And a engines torque is based on engine size and it's hard not to fill the cylinders decently at low rpm so there's floor to how low it can go, but another problem is hp % of torque is smaller at low rpm, 19% @ a 1000 rpm, 38% @ 2000 rpm etc..
I think additional to dyno runs there needs to be more road test how carbs, cams, stall, gearing effects driving, drivability etc..
When your cruising your engine only makes the power needed to maintain that speed or otherwise you’d accelerating.
I’m guessing what we’re looking for how an engine reacts from normal to more aggressive driving at low rpm’s and a normal dyno not gonna tell us that. We need more road test type information on various mods.
So everyone assumes this is for drag racing at WOT?
I don't think you can make that assumption, either.
This is why all these 318 cam threads have the OP going from stock to .600 lift with a 3K converter and 4.88 gears.
It's like people assume any "performance upgrade" is for the maximum top end increase vis-a-vie ET that the person can afford.
Kind of like people that reply to radio threads with "I don't care about a radio because I want to hear the engine".
I do understand the dyno pulls are basically at WOT.
Why did the tester provide the 2K RPM data on the stock engine?
Why NOT show the changes across the board?
Just seems like a little thing to do that doesn't require very much effort and could be useful.
I don't think you can make that assumption, either.
This is why all these 318 cam threads have the OP going from stock to .600 lift with a 3K converter and 4.88 gears.
It's like people assume any "performance upgrade" is for the maximum top end increase vis-a-vie ET that the person can afford.
Kind of like people that reply to radio threads with "I don't care about a radio because I want to hear the engine".
I do understand the dyno pulls are basically at WOT.
Why did the tester provide the 2K RPM data on the stock engine?
Why NOT show the changes across the board?
Just seems like a little thing to do that doesn't require very much effort and could be useful.
From what I understand is a dyno is only good and or easier to setup for a narrow range of rpms.
Richard Holdener did to a test on a engine from like 2000-7000 rpms but had to split the run from like 2000-5000 and 4000-7000 rpm's.
And generally they don't care about under 2500-3500 sometimes even higher rpm's depending on the engine. Your main powerband is around peak tq to 500 ish rpms passed peak hp.
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Here's a 477hp 318/323 dyno's down to 2500 rpm with a fairly big cam, and still makes 337tq @ 2500 rpm. I'm sure the comp xe262h cam that suppose to work 1,300-5,600 rpm is doing fine under 3000 rpm plus the 3-4 400 hp 318 builds all make similar torque as these at 3000 rpms.
Iron-Headed Mopar 318 Magnum Engine- Popular Hot Rodding Magazine
On The Dyno DTS Dyno Data Performance Crankshaft 323CI Small-Block Mopar
On The Dyno DTS Dyno Data Performance Crankshaft 323CI Small-Block Mopar
| RPM | TQ | HP |
| 2,500 | 337 | 161 |
| 2,600 | 350 | 173 |
| 2,700 | 357 | 183 |
| 2,800 | 357 | 190 |
| 2,900 | 356 | 196 |
| 3,000 | 351 | 201 |
| 3,100 | 345 | 204 |
| 3,200 | 339 | 207 |
| 3,300 | 343 | 216 |
| 3,400 | 356 | 230 |
| 3,500 | 371 | 247 |
| 3,600 | 385 | 264 |
| 3,700 | 396 | 279 |
| 3,800 | 404 | 292 |
| 3,900 | 410 | 305 |
| 4,000 | 415 | 316 |
| 4,100 | 418 | 327 |
| 4,200 | 420 | 336 |
| 4,300 | 422 | 345 |
| 4,400 | 421 | 353 |
| 4,500 | 420 | 360 |
| 4,600 | 421 | 369 |
| 4,700 | 425 | 380 |
| 4,800 | 426 | 390 |
| 4,900 | 427 | 398 |
| 5,000 | 427 | 407 |
| 5,100 | 427 | 414 |
| 5,200 | 426 | 421 |
| 5,300 | 425 | 428 |
| 5,400 | 423 | 435 |
| 5,500 | 421 | 440 |
| 5,600 | 419 | 446 |
| 5,700 | 417 | 453 |
| 5,800 | 415 | 458 |
| 5,900 | 412 | 462 |
| 6,000 | 407 | 465 |
| 6,100 | 401 | 466 |
| 6,200 | 397 | 469 |
| 6,300 | 393 | 471 |
| 6,400 | 390 | 475 |
| 6,500 | 386 | 477 |
| 323CI SMALL-BLOCK MOPAR | |
| Bore: | 3.936-inch |
| Stroke: | 3.315-inch |
| Displacement: | 323 cubic inches |
| Compression ratio: | 10.44:1 |
| Camshaft: | COMP solid flat-tappet |
| Cam duration: | 247/247 degrees at .050-inch tappet rise |
| Valve lift: | .622-/.597-inch |
| Rocker ratio: | Harland Sharp 1.7:1 intake; Crane 1.6:1 exhaust |
| Lobe separation: | 105 degrees |
| Intake centerline: | 99 degrees |
| Top ring: | .043-inch Speed Pro barrel face |
| Top ring gap: | .018-inch |
| Second ring: | .063 Speed Pro, scraper |
| Second ring gap: | .018-inch |
| Oil ring: | .187-inch |
| Piston: | Diamond dome, zero cc effective volume |
| Block: | OEM roller 318 |
| Crankshaft: | OEM forged 340 |
| Rods: | Scat SBC 6.200-inch I-beam |
| Main journal: | 2.490-inch |
| Main bearing clearance: | .0022-inch |
| Rod Journal: | 2.100 inch |
| Rod bearing clearance: | .0022-inch |
| Cylinder head: | Mopar Performance R/T Magnum |
| Intake valve diameter: | 2.020-inch |
| Exhaust valve diameter: | 1.600-inch |
| Intake manifold: | Professional Products |
| dual-plane | |
| Carburetor: | RM Competition modified Holley 950 HP |
| Header: | Hooker 1-5/8-inch primaries |
| Ignition: | MSD 6AL |
| Damper: | Professional Products |
| Water pump: | Professional Products small-block Chevy |
@xactorocker : Let us know what rear gears you’re intending on using or intending on using or presently running. There are still several cam choices available that will work with your stock valves and springs, even if they have rotators.
Torque down low is where it's at for a street cruiser. Side stepping the clutch, releasing the trans brake, or loading the converter to peak power is more race stuff than taking off from a stop light especially for a stock or gently warmed over Teen. You can make torque at low RPM where horsepower comes higher up in RPM.
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Rat Bastid
Dunamis Metron
I thought I explained this.
What does drag racing and WOT have to do with each other? Do circle track cars not use WOT? Road race cars?
There is more to dyno testing than just WOT, but to pull an engine dow to 2000 in most cases is just STUPID. It means NOTHING and it’s a waste of time, money and it just adds extra wear and tear on the dyno.
A water brake or even an inertia dyno is NOT for most driveablity issues. That’s not what it’s for. So why abuse a tool for something it’s not designed for?
It’s amazing the number of guys who think what happens at 2000 RPM is critical, or really even important. What matters down that low is mostly a tune up issue.
How well the engine transitions from the idle circuit to the transfer slots and then on to the mains is far more critical that torque. It’s mind boggling how guys get this wrong.
Torque does NOT move the car. Never has, never will. Until you get to peak torque and after (where RPM matters and you make power) the only way to increase the power is to increase the torque.
As I said earlier, it’s not torque at WOT that matters down there. It’s how much torque you make at part throttle. You can jam a bunch of stroke in it and make it a John Deere. Some guys get wood even thinking about that and that’s ok.
But you can have all the torque in the world at 35% throttle and if you don’t get the timing curve correct (ALL engines need a curve and locking out the distributor is bad policy, and the all in by 2000 or 2500 crowd is leaving massive power and driveability on the table because they lack an understanding of how the timing curve works), if you love a giant Main Air Bleed and you are pig rich down low and lean at RPM, if you love as many emulsion holes as big as you can get and your A/F curve looks like a giant saw tooth curve then all that stroke won’t do ****. It will cover up a tuners lack of skill better than an engine with less stroke and more RPM.
That’s all **** you learn on the dyno and you can correct for it IF you know what you are doing.
But whining because the dyno guys don’t drag everything down to cruise RPM and load the hell out of it at WOT doesn’t cut it.
Its not what the tool is for, and doing that is abusive to the tool and the engine.
So to clarify, cars that what people generally call soft down low is from improper tuning? would make sense cause even a big cam low cr engines makes many times more than enough power down low to drive a car.
As for what your saying about torque would be like, If you take pushing your car as an example torque is like the force of you pushing, rpm is like the steps you take, power is both combined, and the more steps a second, quicker you go.
That’s a cam to increase mileage for sure!
I think you are confusing two aspects of this and it starts with what YR is saying and how others are just simply wondering about a low dyno pull rpm test in addition to cam size, and I note see engine usage.
YR is correct in his words but the thinking means more to a race engine while others are wondering what a more mello engine is doing. The only time a below 2500 rpm pull that I could see as useful for s with a very small cam and/or the intended gear ratio that would be very numerically high needing a WOT application below 2500.
There is no doubt that a WOT below 2500 is done with mechanical secondary carbs on street rides, but not really done in heavy hitting street strip/race rides.
194@050 is a mileage cam and the only performance I see in it is the 108 C line. TORQUE IMPROVEMENT!!!!
With the .400 lift, just give it a good valve job to help it out.
With the .400 lift, just give it a good valve job to help it out.
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