Doms T rams carbs out of the box dyno'd

Well i didn't make it to the track this fall with the new tunnel ram set up, but will come spring. I need new tires before i go and i spent enough money this year. I did get it on a chassis dyno today thou. Doms carbs have a very flat curve. Just going up 2 sizes on HSB gained 60hp. Had a 30 in it and went up with a 32. Nice gain. Tried several other thing like removing velocity stacks with screen filter and gain 6hp/4tq. The screens are that restrictive. The data at the bottom of the pages don't match up to whats on the graph. Can't explain that. Looks like 519hp/561TQ at the wheel. The guys at the shop were very impressed with Doms carbs snappyness.

I was very surprised to find peak hp at 6000rpm and peak torque 4600rpm. I thinks its time to ditch the flat tappet and get a big roller in it. Would like to see the peak power at 6500 at least.

Looks like the air was Real good, the correction took Hp away, did you get a uncorrected # also

I don't think so. Humidity 40%, good air. First run it just about jumped off the dyno, had to strap better and then next it crashed the computer. After some time they got things up and running again.

Check out the crank values. Not sure how accurate these are.

Correction factor .998

Ok, i don't know how to use the correction number. What does that tell you?

It made at the time more HP than what is printed out, not much, but a little.it made 499.5 without correction for the weather & corrected 498.8 , no big deal just an observation

Not sure how they get 730 out of 520? My moroso slide rule says 675 with a Dominator. Here's a vid. https://youtu.be/qq5b9mIvJMU

Their crank values to wheel values are absurd, that would be generating a massive amount of heat to have that kind of loss..

That was my point. I can also say Mustang dyno's sap a lot of power from your rear wheel number, but that was not the reason for going. I just needed the peak rpm numbers and the fuel curve data and i am happy with that. I just looked at my Moroso slide calculator and using mph and weight it gives 630hp using my single 1100 dominator. So with tunnel ram i would think 660-680 crank hp would be more accurate, but who knows.

Chassis dyno power curves, especially those that are derived from a combo with a loose converter won’t look anything like what the curve would look like from an engine dyno.

Unless something very very odd is going on with that combo, there is no way the engine TQ numbers will be higher than the HP numbers on your build.



Especially the TQ value.

Didn't know that, but wouldn't this curve look the same as the car go's down the track?

Mustang Dyno's always do that.....lol

The last time i was on a Mustang dyno, it had me down 200hp. I had a small block then. The dyno run yesterday did show where my peaks are and i don't like where their at. Also Dom's carbs flat fuel curve after peak tq.

I used to work in a shop with a Dynojet wheel dyno. With an auto and loose converter numbers would be all over the place. We did a S/C small block Vette that made 414 on the dyno, but ran 8:6X@153.

Thats what i'm talkin about. I do think the Dynojets are more accurate than the Mustang thou if your looking at hp/tq numbers. The graphs off the dynojet are better laid out as well.

You can't really look at them as accurate IMO. You just have to look at it as a number, if you leave there and that number, whatever it is, is higher than when you got there you made an improvement. That being the case you also need to stick to one dyno and operator to be able to do comparisons on each trip.

I agree. The are a tool.

And this is why I don't dyno my chit.....

Well ya know i did get the data i wanted. I did not go to get hp numbers. I learned years ago those were not accurate at best. I went to get peak rpm numbers and a fuel curve. To me this was valuable info and well worth $150.

I have a dynojet and can run a negative dyno test to get drivetrain losses in inertia mode., I am not sure how the mustang derives those numbers using a load cell.
I work on other types of machinery that uses the same strain gauges that a lot of load cell dyno's use, they need to be calibrated between 2 or more data points and on a regular basis.. I know some
other dyno's just have a zero'ing function but that doesn't mean anything. I have the load cell option on my dynojet, you zero it, and then put a fixed weight on a torque bar to see if the gauge is reading right.

That's not a bad price...Around here its $500 to get near one....

It does look like you got a chance to do some tunning....Get it to the track and take some jets!

My takeaway from the chassis (and engine) dyno was the same as yours. It's a tool to see changes made in the tune, the numbers fall where they will.

Ok, so Dwayne, you know this sft cam. So what duration in a roller would pick my peak power and torque up 500 rpm if the cam was on a 108 lobe sep in this combo? I just need a rough idea. Thanks