I have a 77 Nova (That Rusty Piece of S --- In The Driveway)with a 350 sbc(.040 over).  I currently run World Products heads (9 to 1 compression) and a Crane cam with 228 degrees duration and .480 lift @.050.  

I recently had the car on a chassis dyno and came away with 240 hp @4700 rpm and 290 lb-ft of torque @ 3900 rpm at the wheels.  

How do I relate this back to the flywheel?  The operator said the average powertrain loss is 20-25%.  If that's the case, a more powerful engine would lose more power than a weaker one through the same drivetrain.  It seems to me that it should be a finite number for a given drivetrain, rather than a percentage of power.  I have a th350 trans with a 2500 stall converter and 10 bolt rear.  The car has power steering, a manual water pump, and factory clutch fan.

Also, does anyone know how much replacing the water pump and fan with electric units would be worth?  How about roller rockers (1.5 intake and 1.6 exhaust)?  

I know it's a lot of questions, but I can't afford to experiment too much and need as much info up front as possible.  Thanks very much....  

What intake are you using and what is the cfm of the carb. on the engine.  

I'm using a Holley 770 Street Avenger with a one inch spacer and an Edelbrock Performer dual plane manifold.  

Do you have headers on the engine and what gear ratio is in the rear end.Also what world heads do you have are they sportsman or torkers or sr torkers and what type of pistons do you have flat tops or dish top.If possible a part# on the heads.  

The heads are Sr Torkers, 76cc chambers, 170cc runners, 2.02 and 1.60 valves, flat top hyper pistons (9to1 compression).
I have 1 5/8 inch headers into a 2.5 inch exhaust, H-pipe, and Flowmaster mufflers with full tailpipes.
The rear is a 7.5 inch with 3.73 gears, locker, and 26 inch tall BFG Drag Radials.  

YOUR H.P. SEEMS TO BE A BIT LOW OR YOU ARE REALLY LOOSING ALOT THRU DRIVE TRAIN LOSS. YOUR PEAK H.P. AT 4700 RPM IS TELLING ME SOMETHINGS NOT RIGHT OR PROPERLY MATCHED. JUST BY REPLACING THE FAN WITH A ELECTRIC ONE WILL NET YOU 10-15 H.P. AND BETTER YOUR M.P.G. I WOULDN'T RUN AN ELECTRIC WATER PUMP ON A STREET CAR. THEY WILL WORK AND ALL THAT BUT THEY DONT LAST THAT LONG WHEN YOU USE THEM EVERYDAY. THIS IS WHY THE OEM'S ARE STILL USING BELT DRIVEN WATER PUMPS. GET A HIGH FLOW WATER PUMP. THEY USE ABOUT 5 H.P. I USE A PRO COMP ALUM. WATER PUMP GOING ON 2 YEARS NOW WITH NO PROBLEMS. THE USE OF AN ELECTRIC FAN WILL HELP YOUR WATER PUMP LIVE ALOT LONGER. JUST MAKE SURE YOU GET ONE WITH ENOUGH CFM TO COOL YOUR MOTOR (SHOULD BE THERMOSTAT ON/OFF NOT CHEAP TOGGLE SWITCH)....ROLLER ROCKERS ALWAYS HELP AS ANY THING DONE TO GET RID OFF FRICTION IS A PLUS. WITH A .480 LIFT CAM YOU SHOULD BE USING THEM ANYWAYS. STOCK STYLE ROCKERS CANT HANDLE HIGH LIFT CAMS (YOUR REALLY PUSHING THE LIMIT WITH YOUR CAM). IF YOU RUN A SPLIT SET PUT THE 1.6 ON THE INTAKE AND 1.5 ON THE EXHAUST. FOR YOUR COMBO I WOULD JUST USE 1.5'S. 1.6 IS HARDER ON THE VALVE GUIDE AND MIGHT RUN INTO PISTON-VALVE CLEARANCE. NOT TO MENTION DIFFERENT LENGHT PUSH RODS. IF YOU DO GO WITH ROLLER ROCKERS YOU WILL NEED GUIDE PLATES, AND IF YOUR WORLD PRODUCT HEADS DONT HAVE THEM (WHICH MANY DONT) THATS SOMETHING ELSE TO CONSIDER.......MOST CARS LOSE 20-25% SOME HIGH DOLLAR RACERS CAN GET IT UNDER 20%. AND YES ITS HARD TO EXPLAIN BUT THE MORE POWER YOU MAKE THE MORE GETS LOST. A 200 H.P. MOTOR MIGHT PUT 150-160 H.P. TO THE GROUND AND A 1,000 H.P. MOTOR MIGHT PUT 750-800 TO THE GROUND WITH THE SAME DRIVE TRAIN.  ITS REALLY HARD TO GIVE A EXACT NUMBER BUT I'D SAY WITH YOUR COMBO AND 240 H.P. ON THE GROUND--YOUR MOTOR SHOULD HAVE 325-350 H.P.  

Ok 76 cc chambers on a flat top piston only give you a 8.5:1 c.r. will be back with a engine horse power rating later and more info.What is the timing set at.also what is the outer diameter of the tires.  

Total timing at wot is 36 degrees, 16 degrees initial.  I had the long block built and specified 9 to 1 compression for octane purposes and for possibly adding a supercharger later.  I don't have the spec sheet with me, so I may be incorrect on the piston design.  I am sure about the compression, though.

Thanks for all the help.  

The heads have guideplates and hardened pushrods.  The current rockers are standard 1.5s
The Summit catalog says the heads can take up to .560 lift, which is why I'm considering the 1.6 rockers.  They should bring it up to .512
Also, the tires are 275/50/R15 (26x10).
Is there a way to tell if my fan disengages based on rpm or temp?  Also, at what rpm does such a fan disengage?
The rwhp seems low to me too, although the torque is decent.  If anyone can pick out the weak spot, I'd appreciate any suggestions.  

With all the specs. of the engine you should have around 360 horsepower you should of turn the engine up higher in rpm like around 5500rpm or a little higher because that cam doesn't start building power until 2800 rpm.I would recomend the 1.6 roller rockers that would help free up some horsepower as well.  

HEADS ADVERTISE LIFT BASED ON THE SPRINGS. YES A 1.6 WILL GIVE MORE POWER. YOUR WORLD HEADS CAN FLOW ENOUGH TO MAKE USE OF THE EXTRA LIFT. JUST MAKE SURE YOU HAVE TO RIGHT SIZE PUSH RODS. DOES YOUR CLUTCH FAN HAVE A THERMOSTAT. THIS IS A FLAT WIRE COIL ON THE FRONT OF THE FAN. LOOKS LIKE A HOUSE THERMOSTAT. I RUN WORD S/R HEADS ON MY MOTOR. THEY ARE GOOD HEADS BUT WHEN I HAD THEM PORTED THEY BECAME GREAT HEADS. WELL WORTH THE MONEY. I'LL BE BACK IN A COUPLE MINUTES WITH A WEB SITE THAT HAS THE FLOW NUMBERS OF YOUR HEADS.  

o.k. go to    http://racingdownloads.com/racing_software-26.html  this site has flow numbers for stock heads, arf, edelbrock, world, ect...  

Thanks for the info guys.  360hp sounds about right, but I still think 240rwhp is a bit low.  That seems like alot to lose thru the drivetrain.  Could I lose that much with the fan, water pump, and power steering?Any thoughts?

My local track starts test & tune days on 3/1.  Before then I hope to have the new 1.6 rockers and fan in place.  I still may try the electric water pump, since the car isn't driven every single day.  I'll let you know how it turns out.  

YEA I GUESS ON A HIGH SIDE YOU COULD LOSE THAT MUCH. EVERYTHING COMES INTO PLAY HERE--LIKE FAN, WATER PUMP, TRANS, DRIVESHAFT, REAR AXLE, TIRES, RIMS ECT. ANYTHING YOU CAN DO TO LIGHTEN THINGS UP WILL HELP. LIKE THE TIRES-RIMS-ALUMINUM DRIVE SHAFT...THINGS LIKE ROYAL PURPLE GEAR LUBE IN THE REAR END HELPS JUST A BIT. WHEN YOUR TRACK OPENS UP AND YOU TEST AND TUNE, USE YOUR MPH AS A GUIDE AND NOT THE TIME. YOUR TIME WILL VARY OFTEN DUE TO TIRE SPIN. EVEN WHEN YOU THINK THERE NOT SPINNING THEY STILL MIGHT BE A BIT. ANYTHING YOU DO THAT CAUSES AN INCREASE IN MPH IS A INCREASE IN H.P. TO THE GROUND. I USE A MOROSO WATER PUMP DRIVE KIT ONLY AT THE TRACK. WHEN I GET THERE IT TAKES ABOUT 5 MINUTES TO SWAP IT OVER. THE ONLY REASON I USE THIS IS SO I CAN RUN THE WATER PUMP (INCONJUCTION WITH THE ELECTRIC FAN) WHILE THE MOTOR IS OFF TO REALLY COOL IT DOWN BEFORE I RUN AGAIN. WHEN I HAVE JUST USED THE MANUAL WATER PUMP I HAVE YET TO SEE ANY DIFERENCE IN THE 1/4. I DO HAVE A HIGH FLOW PUMP THAT CLAIMS TO USE LESS H.P. THAN A FACTORY UNIT. IF YOU REALLY WANT TO LEARN FIRST HAND FOR YOUR SELF, DONT CHANGE ANYTHING UNTIL YOU HAVE RUN THE 1/4 A FEW TIMES. THEN START CHANGING THINGS AND YOU WILL KNOW FOR YOURSELF WHAT WORKS AND HOW MUCH. THATS HOW I LEARN.  

ONE OTHER THING TO KEEP IN MIND. A DYNO JUST LIKE ALL EQUIPMENT CAN BE OFF A BIT AND GIVE A FALSE READING. I HAVE A FRIEND WHO BOUGHT A BRAND NEW HIGH DOLLAR TIMMING LIGHT. HE USED IT ON A FRESH MOTOR AFTER BREAK IN AND WE KNEW RIGHT AWAY THAT SOMETHING SEEM TO BE OFF IN THE MOTOR. WE WERE SURE IT WAS IN THE TIMMING AND TO MAKE A LONG STORY SHORT--AFTER COMPARING HIS NEW HIGH DOLLAR LIGHT TO 3 OTHER LIGHTS FOUND IT WAS WAY OFF. TOOK IT BACK GOT A DIFFERENT ONE AND IT WAS FINE. IF YOU DONT MIND ME ASKING HOW MUCH DO THEY CHARGE TO USE A CHASSIS DYNO?