Don Terrill’s Speed-Talk

Gregory wrote: ↑Fri Jun 19, 2020 3:01 pm Here's the pop quiz for the week:
The School Of Automotive Machinist (SAM) came in a close second at the 2012 EMC with their 402 cu in SB2 in the Xtreme Street class.
The same engine was entered in the Race Engine Challenge (REC) in 2019 with only the following differences:
* The 2012 EMC engine had 15:1 compression, .800 lift (net I assume since there was no lift rule) and a tub oil pan.
* The 2019 REC engine had 11:9 compression, .775 zero lash cam lift rule and a stepped oil pan.
Yes they were on a different dyno, but we are confident they were both calibrated correctly.
Question: How much power did it lose in 2019 and how much average power did in lose between 4,000 and 7,500 RPM's.
What's your guess? The answers may surprise you and will be posted in a couple of days.
www.RaceEngineChallenge.com

David Vizard wrote: ↑Tue Jun 23, 2020 5:22 pm I think some might question my eligibility to guess at this since I have experience with both dyno's. I know the UNO dyno read slightly high for the 2012 shootout as we had an engine on it for another project for my BBC book - all to do with ex pipe lengths.

I am sort of hoping some of my critics may make a guese here to see if they show me up. Lets see. Anyway my guess here is about 30 Hp on peak with, over the test range involved, about 12 hp average. Now lets see if 500,000 plus dyno pull experience earns me any credits.

DV

CGT wrote: ↑Wed Jun 24, 2020 9:15 am The EMC dyno calibration has been all over the place through the years....

Walter R. Malik wrote: ↑Tue Jun 23, 2020 8:02 pm
David, I don't know about dyno compatibility and the differences you found but, these were the numbers posted.

At the 2011 EMC Contest
... 813.1 H.P @ 7,100 RPM
... 660.0 lb/ft Torque @ 5,900 RPM

At the 2019 REC Contest
...780.8 H.P. @ 7,000 RPM
...644.1 lb/ft Torque @ 5,900 RPM

David Vizard wrote: ↑Tue Jun 23, 2020 5:22 pm I think some might question my eligibility to guess at this since I have experience with both dyno's. I know the UNO dyno read slightly high for the 2012 shootout as we had an engine on it for another project for my BBC book - all to do with ex pipe lengths.

I am sort of hoping some of my critics may make a guese here to see if they show me up. Lets see. Anyway my guess here is about 30 Hp on peak with, over the test range involved, about 12 hp average. Now lets see if 500,000 plus dyno pull experience earns me any credits.

DV

Warp Speed wrote: ↑Thu Jun 25, 2020 5:00 am 500,000+ dyno pulls = 27+ pulls per day, 7 days a week, 365 days a year for 50 years.
Impressive!