Need input on Dyno results please...

[Dan Norcal]

Hi all I’m new here, need someone with 408 stroker and Dyno knowledge. I have a 1973 Duster that I’m putting a motor in and the builder sent me the Dyno specs and somthing doesn’t seem right to me? I’m not trying to bash anyone I want to keep a good relationship with these guys but somthing seems off with other Dyno sheets I’ve looked at from the same builder and others. The Dyno says 600 ft lbs of torque at 3800 rpm?? Horsepower is 500 at 4600 and hangs there till about 5500. If this is correct I’m stoked but it seems like the torque is off the chart for a 408, ede rpm headed, hydraulic roller, on pump gas. As you can see it’s a mild idle motor nothing radical. I hope I’m not being played, seems about 50 to 60 ft lbs high, which would make the hp less to right?
Here is the video. Thanks for your input.

 

[dukeboy440]

Hi all I’m new here, need someone with 408 stroker and Dyno knowledge. I have a 1973 Duster that I’m putting a motor in and the builder sent me the Dyno specs and somthing doesn’t seem right to me? I’m not trying to bash anyone I want to keep a good relationship with these guys but somthing seems off with other Dyno sheets I’ve looked at from the same builder and others. The Dyno says 600 ft lbs of torque at 3800 rpm?? Horsepower is 500 at 4600 and hangs there till about 5500. If this is correct I’m stoked but it seems like the torque is off the chart for a 408, ede rpm headed, hydraulic roller, on pump gas. As you can see it’s a mild idle motor nothing radical. I hope I’m not being played, seems about 50 to 60 ft lbs high, which would make the hp less to right?
Here is the video. Thanks for your input.

where's the sheets?

 

[Dan Norcal]

Sorry Dyno run isn’t at end... trying to figure out how to copy PDF from email using iPad

 

[Dan Norcal]

“Is” not isn’t

 

[jimjimjimmy]

it very well could of made 500hp at 4600 but no way it made 600 fpt based on my experience with strokers

 

[Dan Norcal]

Maybe this will work

 

[Dan Norcal]

it very well could of made 500hp at 4600 but no way it made 600 fpt based on my experience with strokers

That’s kinda where I’m at. It’s like somthing is off on the dyno or it got “adjusted” but I don’t know enough about dyno’s.

 

[dukeboy440]

That’s kinda where I’m at. It’s like somthing is off on the dyno or it got “adjusted” but I don’t know enough about dyno’s.

its possible the setting they have the dyno load set on could be magnifying the torque slightly.

 

[Dan Norcal]

its possible the setting they have the dyno load set on could be magnifying the torque slightly.

So not a red flag? My goal is to get in the 11’s every once in a while at the strip and the numbers don’t mean much if that happens. 3.91 gears, 3000 stall, 3400lbs with me in it.

 

[dukeboy440]

So not a red flag? My goal is to get in the 11’s every once in a while at the strip and the numbers don’t mean much if that happens. 3.91 gears, 3000 stall, 3400lbs with me in it.

I think you'll be there. If its truly making 500 HP and assuming it'll hook, you'll be in the mid to high 11s.

 

[roccodart440]

Dyno results vary. What they are is a safe way to break in an engine in a controlled environment and a great way to tune an engine so it's drop in and run ready and running the best it's going to run.

I'm not sure what my current engine makes at the crank. It's built very similar to my last engine so it's in the ballpark of 475/514 at the crank and makes 314/550 at the wheels. It goes 11.70's in a real street car.

 

[mario03srt]

Dan,

What dyno is he using? Is the uncorrected numbers or SAE corrected? What is your cam duration? That's a nice flat HP curve fo sho! Like a SC graph.

Marion

 

[yellow rose]

So not a red flag? My goal is to get in the 11’s every once in a while at the strip and the numbers don’t mean much if that happens. 3.91 gears, 3000 stall, 3400lbs with me in it.

450 HP in a 3500 pound car is low 11's. Seen many 12 second 500 HP cars out there.

 

[qkcuda]

My 500 stroker initially made 610 lb/ft of torque and 550 HP on the dyno with ported 452 heads. I would be surprised if an engine 100 cubic inches smaller would make that much torque. This was my dyno sheet for comparison.

 

[273]

1.5 Lbs-ft per cid would make 600 lbs-ft.
Is it impossible, Im sure theres an engine or 2 that has hit that level. Most decent builds are gonna be 1.15-1.25 lbs-ft per cid, mid builds with great heads and intakes decent roller cams make 1.25-1.35 lbs-ft. 1.35-1.45 lbs-ft plus would be a highly massage high effort engines.

 

[Dan Norcal]

Dan,

What dyno is he using? Is the uncorrected numbers or SAE corrected? What is your cam duration? That's a nice flat HP curve fo sho! Like a SC graph.

Marion

Dynomite? Not sure on settings and sadly not sure on the cam, custom ground CompCam. That was known upfront but it was a little hard for me not to know.

 

[dukeboy440]

Dynomite? Not sure on settings and sadly not sure on the cam, custom ground CompCam. That was known upfront but it was a little hard for me not to know.

get a print out with all the specs from the builder as well as the full dyno printouts.

 

[Dan Norcal]

450 HP in a 3500 pound car is low 11's. Seen many 12 second 500 HP cars out there.

Yeah I hope to not be the later guy with the wrong setup and narcolepsy

 

[Dan Norcal]

1.5 Lbs-ft per cid would make 600 lbs-ft.
Is it impossible, Im sure theres an engine or 2 that has hit that level. Most decent builds are gonna be 1.15-1.25 lbs-ft per cid, mid builds with great heads and intakes decent roller cams make 1.25-1.35 lbs-ft. 1.35-1.45 lbs-ft plus would be a highly massage high effort engines.

I sent them an email yesterday asking about the number on the torque, they haven’t got back yet. Like I said if it’s correct I got a crazy odd perfectly tuned and matched setup with angel kisses on it. But I’m guessing it’s a mechanical/ software hiccup

 

[roccodart440]

Yeah I hope to not be the later guy with the wrong setup and narcolepsy

Falling asleep at the light doesn't change your ET.

 

[nm9stheham]

It's the green paint on the block...... It throws off the dyno software calibration.
(Seriously, that calibration and any corrections are actually what I would question here, and are total unknowns at this point. 'Standard' setup means what exactly?)

 

[qkcuda]

It's the green paint on the block...... It throws off the dyno software calibration.
(Seriously, that calibration and any corrections are actually what I would question here, and are total unknowns at this point. 'Standard' setup means what exactly?)

It's Kryptonite!

 

[RustyRatRod]

They have a happy dyno. All there is to it.

But as said, don;t get hung up in dyno numbers. They all vary. Drag strip numbers do not.

 

[rmchrgr]

600 ft lbs of torque is a lot but I don't think it's way out of line. My solid FT 416 made similar numbers - not 600 lb ft of torque mind you but pretty much 500 ft lbs from 3,800 rpm - 5,500 rpm and 500 hp on the dot at 6,000 rpm. Strokers generally have a broad, flat torque curve. Plus, a dual plane intake and hydraulic roller cam will amplify that. Is the cam advanced? If so, how much?

I would want to find out what the fuel lbs/hr and BSFC numbers look like to see if they correlate to the indicated performance. My BSFC was not optimal so power was left on the table. Not sure to what extent, I didn't do any tuning to try and correct that. Chasing BSFC numbers can be a worm hole, meaning that the inefficiency can be a design flaw.

Also, the correction factor is standard so maybe find out how much actual correction was going on. On the day I ran my engine on the dyno, correction lopped off almost 25 hp from the raw data.

 

[crackedback]

No way does it make 600 tq.... Not gonna happen.

OOTB edelbrock heads? Cam specs? Those two would go a long way towards a better number for HP/TQ.

If it's makes 500hp and 500tq... be happy and move on. I think those TQ numbers are WAY off.

Put it in the car and run it at a track. 1/4 MPH will tell you what is going on for power.

Here is something to compare your to. This one has a BUNCH more steam in it and only got to 541tq!
How To Build A Pump-Gas 620hp Small-Block Mopar - Car Craft Magazine