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Monty 12-23-2003 03:59 PM

Intial Dart 540, AFR 315CNC Dyno Results
 
We finally got to make our first good pull today on one of the Dart 540's. We got the first engine on the dyno last Wednesday but we didn't make a full pull until today because of some missing and popping in the midrange rpms. The carb and distributor were right out of the box, and we could tell from the fuel lb/hr and plugs that it was running pretty rich so we initially thought that was the cause. Then I had a death in the family and had to go out of town so we didn't have a chance to make any more pulls until today.

It turned out the the brand new MSD Pro-Billet distributor had a bad pickup module. After fooling with the carb and timing, and changing wires and plugs, we finally swapped the distributor off of the other 540 that is still on the engine stand. The missing and popping cleared up right away. So the results of the first "good" pull, but with not carb tuning (still running real rich) and only 30* total timing with baseline springs and weights the results are as follow. With tuning, ~700hp and ~675tq seems very realistic. My parents are in town so I couldn't stay for any more pulls, but they're going to call me with the final results tomorrow.

The basic combo is: Dart Big M block, 9.0:1 static compression, 4.500" bore x 4.25" stroke, 9.800" deck, Crane 741 hydraulic roller cam, Crane roller lifters, AFR 315 CNC heads with backcut Del West stainless intake valve, Del West inconel exhaust valves, Isky (PSI) "Tool Room" springs, Crower stainless rockers, JE forged pistons, Crower 4340 billet 6.386 rods, Crower semi-lightweight 4340NT crank, Victor Jr intake, Holley marine 850cfm 4150 carbs, MSD Pro-Billet Distributor, etc....

RPM.......TQ.......HP
4000.....643......490
4100.....644......503
4200.....644......515
4300.....649......532
4400.....654......548
4500.....655......561
4600.....660......578
4700.....660......590
4800.....655......599
4900.....652......609
5000.....651......619
5100.....648......629
5200.....645......639
5300.....642......649
5400.....638......656
5500.....635......665

Strip Poker 388 12-23-2003 04:29 PM

Thats a flat TQ curve:D Did you pull it below 4000?
I bet it would run better with more carb.I am running a 925cfm Barry grant on a 350 ci in my Chevelle.it made 542hp at 7250.just change to dart pro one hoping to step it up alittle:D :D

Cord 12-23-2003 04:33 PM

Almost the exact same engine as mine. Victor Jr intake, 540, 741 cam...except for the heads. Oh, yea and my engine made about 50 less hp. But it was also over 100 in the dyno cell with a humidity to match.

KAAMA 12-23-2003 07:06 PM

If he used a 950cfm Holley he we probably pick up something like another 15hp on top. Those are pretty KILLER numbers though for 9.0 cr engine with an 850 Holley. Sounds like you more than met your power goals for these engines----Congrats Monty! :)

martiniboat 12-23-2003 09:07 PM

I'm liking those torque figures...:drool: :drool: :drool:

Brian

SSComp 12-23-2003 09:22 PM

The Crane 731 seems to be getting "standard" for most applications. I've got them in my new 509 Blower motors.

Great numbers.

tomcat 12-23-2003 09:48 PM

Hey Monty:

Very nice results, thanks for posting them. It's easy to calculate the volumetric efficiency curve for the engine. I just did it at 5600 RPM and got 102.4%. Congrats!

cobra marty 12-24-2003 04:04 AM

Now just add a blower to it.

dyno 12-24-2003 07:16 AM

Looks Great!!! Congrats!!Merry Christmas to you......now bolt them in and hold on!

Monty 12-24-2003 11:17 AM

Thanks guys. I haven't even put the boat in the water yet, so now I'm really looking forward to Spring.

I'll post the numbers below 4000 next Monday, Fast Times is closed for the rest of the week. When we were trying to isolate the cause of the missing and popping the first day, we put a Holley HP 950 on it and the difference was less than 10hp above 5000 rpm. The 850 actually made more power and torque below 4800 and helped create more area under the curve. I could probably make up the difference with a carb spacer, but I've already got to deal with how I'm going to raise the hatches 2-3" as it is.

I've got TRS drives so my rpms will be chip limited to less than 5500 and I'm probably already pushing their limits, so I've been told. My goal was a solid 625-650 hp and tq, so I'm more than satisfied. Several people questioned the use of the "small" heads, cams, and carbs, but I felt this combination was a good fit for my application and limitations (drives). While performance was important, reliability and durability are more important.


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