Dyno testing a stock(?) 1972 440

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IQ52 said:
Lets put on those High Performance exhaust manifolds and see what happens.
Click to expand...

We tested this last year too. Went from center dump Truck manifolds tot the fancy HP manifolds and gained about the same you did, nothing.

And the small gian with the headers is about right for a stockish, low performance engine thats no flowing much air thru it. When all is said and done and you have the most power out of this combo, it would be interesting to see what happens when you put the manifolds back on. Wonder if it would only be a 22hp drop????
 
One more change. Lesse, what carburetors do we have laying around? Oh, howsabout this 750 cfm Edelbrock Performer. Yeah, bolt that dude on!

RPM..............TQ.............HP

2500............432............206
2600............423............209
2700............419............216
2800............419............223
2900............421............232
3000............424............242
3100............422............249
3200............421............256
3300............416............261
3400............412............267
3500............406............270
3600............399............274
3700............395............278
3800............391............283
3900............383............285
4000............376............286
4100............370............289
4200............368 +32......294 +26
4300............363 +31......297 +25
4400............350............293
4500............338............290
4600............326............285
4700............313............283
4800............305............279
4900............286............267
5000............274............261
5100............266............259
5200............247............244
5300............237............239
5400............231............238
5500............207............217

Now, all we have done is add headers and a bigger carburetor and we have gained 31 LB-FT and 25 HP at 4200-4300 rpm from the 1st pull. Just changing the carburetor we gain torque and horsepower across the entire rpm range. We're getting close to 300 HP.
 
This is really interesting stuff.
A question I have is about the increase you picked up from the carb. I'm assuming it had a TQ on it which are supposed to be close to 800cfm. If the TQ was running properly than the HP figures shouldn't be that much different.
Or am I missing something.
 
scrappydoo said:
This is really interesting stuff.
A question I have is about the increase you picked up from the carb. I'm assuming it had a TQ on it which are supposed to be close to 800cfm. If the TQ was running properly than the HP figures shouldn't be that much different.
Or am I missing something.
Click to expand...

Your missing something.........post #13........where we say we're using a 600 cfm Carter. The manifold, used through '72, has a 4150 carb bolt pattern on it.

We are still getting a vacuum signal in the intake of 1.5"-2" in the upper RPMs. The engine is telling us the 750 is too small even with the stock manifold. We've decided to not go with a bigger carb until we change the manifold.

Let's do that, let's go with the Mopar Performance M1 single plane.

Now don't fuss with me folks, its my game and we're not using a dual plane this time even if you want me to.

RPM..............TQ...............HP

2500............416..............198
2600............409..............202
2700............405..............208
2800............404..............215
2900............404..............223
3000............415..............237
3100............421..............248
3200............422..............257
3300............422..............265
3400............420..............272
3500............418..............279
3600............414..............284
3700............408..............287
3800............407..............294
3900............399..............296
4000............395..............301
4100............391..............305
4200............387..............309
4300............381..............312
4400............371..............311
4500............363..............311
4600............348..............305
4700............335..............300
4800............322..............294
4900............311..............290
5000............298..............283
5100............280..............272
5200............263..............263

At least we broke the 300 HP barrier. Now we toss in the 509 cam and shoot for 350 HP with less than 8:1 compression. We know we'll lose some bottom end torque, but can we gain enough everywhere else to make it worth it?
 
Nice Jim!!
Will you play this game with a small block at some point as well ?
 
So with the M1 and 750, you shifted the peak torque band up 1000rpm or so. But peak HP is still very low, but carrying higher rpm potential. The cam swap is a Big change and really going to wake up the top end. My guess 5000-5200 is where peak power will be and 4000-4200 for peak torque.
 
MRL Performance said:
So with the M1 and 750, you shifted the peak torque band up 1000rpm or so. But peak HP is still very low, but carrying higher rpm potential. The cam swap is a Big change and really going to wake up the top end. My guess 5000-5200 is where peak power will be and 4000-4200 for peak torque.
Click to expand...

Since torque moves the car and he has 422 LB FT of it, I say he's kickin ***.
 
^^^ Yes,and then some. Been around builds like this,never seen actual dyno numbers. These builds,always hauled patootie.
 
PEAK numbers are moving, but street use ranges are still good or even improving as well.

I always knew my torker intake didn't rob me of low rpm torque, even though everyone else seems to think so.
 
Let's do the cam and carburetor swap side by side.

Installed the 509 and then installed an 850 cfm Mighty Demon. The fuel lines for the Demon hit the ignition coil towers so I just slipped a 2" Super Sucker 4 into 1 carburetor spacer between the intake and carb to get some clearance.

........................509........................850 carb & spacer

RPM.................TQ/HP...........................TQ/HP

2500...............360/171.........................359/171
2600...............371/183.........................373/184
2700...............384/197.........................382/196
2800...............396/211.........................392/209
2900...............407/225.........................412/227
3000...............409/234.........................431/246 oh oh, whats happening?
3100...............415/245.........................441/261
3200...............425/259.........................442/269
3300...............436/274 max TQ..............450/283 max TQ
3400...............432/280.........................449/290
3500...............432/288.........................441/294
3600...............430/295.........................436/299
3700...............428/302.........................435/306
3800...............425/307.........................430/311
3900...............421/312.........................434/322
4000...............419/319.........................438/333 we're getting there
4100...............419/327.........................445/347
4200...............419/335.........................444/355 yeah!
4300...............416/341.........................443/362
4400...............412/345.........................434/363
4500...............403/346.........................432/370
4600...............399/349.........................429/376
4700...............400/358.........................427/382
4800...............389/356.........................419/383
4900...............388/362 max HP..............415/387 max HP, heh heh 7.45:1 compression
5000...............377/359.........................405/386
5100...............366/355.........................391/379
5200...............359/355.........................383/379
5300...............345/348.........................374/377
5400...................................................361/372

We gave it some air and it won't quit pulling. Wait until you see the torque curve with the cylinder heads! Low compression FREIGHT TRAIN!
 
I have to go to work so lets get the last pull done.

Head swap from stock 906 to ported 516.

This pull is for you Rob, here are are you head flows.

lift..........IN/EXH

.100........85/62
.200......160/132
.300......210/182
.400......237/203
.500......250/216
.600......261/229

Thats all the flow you get this time.

But what can it achieve on a low compression 440? With the 516's we are now all the way up to 7.85:1 compression, woo-hoo!

We're still using STOCK ROCKER ARMS but w/ adjustable pushrods, it's not even lifting to .500".

RPM..............TQ............HP

3000.............434..........248 my test, I'll start the RPM where I want.
3100.............445..........263
3200.............457..........278
3300.............458..........288
3400.............462..........299
3500.............458..........305
3600.............447..........307
3700.............443..........312
3800.............443..........321
3900.............446..........331
4000.............450..........343
4100.............453..........354
4200.............461..........368
4300.............463..........379
4400.............461..........386
4500.............470..........402 402 HP? hang on!
4600.............473..........414 peak torque? really, there is a peak? maybe a plateau.....
4700.............468..........418
4800.............467..........427
4900.............459..........428
5000.............459..........437
5100.............453..........439
5200.............453..........448 1 HP/CI
5300.............445..........449 Peak HP
5400.............428..........440
5500.............421..........441
5600.............407..........434
5700.............397..........431
5800.............391..........431

No, your lookin' at it right, 431 HP at 5800 RPM. Look at the torque! You could put this 440 in a cement truck and it would boogie!

Betcha the value of old motorhome engines just went up!
 
This makes me rethink my 516 heads. Thanks Jim. This is very informative. So to me, this is the PROOF that flow trumps compression for power.
 
MRL Performance said:
Very cool! So it will run on 80 octane fuel right?
Click to expand...

We've got 91 in the dyno fuel cell, so we just ran it on that. As soon a we test it on 85 we'll let you know. I'm really not worried about 85 but we do need to test it so we're positive.
 
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