Reply to "Dyno Day the First"

> Bravo Dan and Dave!
>
> Thanks for all your efforts Dan. This makes for very interesting
>reading. I look forward to the next instalment!
>
> All good stuff.

Thanks guys. It's going to be fun.

> I think it won't be long before you're banging on the 500bhp door.

Dave's dyno is a unit that he built using a Land and Sea absorber,
electronics and software. It's on wheels so it can be rolled in
and out of the shop. We do the pulls under a car port type awning.
The dyno is know to be 4 to 5% conservative when comparing the same
engine on his dyno and the dynos used for the Engine Masters Competition,
at Competition Cams and at Bill Mitchell's. Also, Dave doesn't use the
automatic correction. Instead, Dave enters the atmospheric data manually
from a weather station and no inertial correction factor is used. With
these variables, dynos can vary by 10% very easily. If we take our best
single plane pull from the first day (416 HP), add the 5 HP we lost from
pulling back on the timing and then increase it by the known 5% correction
factor, we'd end up with 442 HP. However, I'm not too concerned about the
absolute numbers. It's more important to see what the relative changes
are between different parts.

> I really looking forward to you guys testing my little 4180, a highly
> underated little carb. I'm sure it will be fine on a bone stock
> Cleveland offering reasonable perfomance down stairs and great mileage.

I think it would work very well on a stock 351C. I was hoping to test
it on the relatively stock 351C in my white Pantera but didn't get a
chance to try it before the snow started falling. It will be interesting
to see what the dyno says. Given the HP difference between the dyno carb
and the 4180, I should be able to predict where the carb will start to
be a restriction.

> Do we worry about that in a DT?

Not too much, though I recently took a 900 mile trip in the Pantera.
Fuel economy was right around 20 MPG, IIRC. Luckily, fuel cost had
dropped to $1.37 per gallon. The recent drop in prices is very
welcome as the dyno is a 200 mile round trip.

Dan Jones