Great Teams Produce Great Results
Back with the fantastic crew at BES Racing Engines today, where we had hopes we had further improved Brian Bednar’s, Dr. OldsMopar himself, carbureted 420 G3 Hemi (I think I mistakenly wrote it was a 426 last time we tested it). Master class builder Ben did another fine job building it and Michael getting it on the dyno and testing / tuning with us.
Brian has been a killer with the car in the 9.50 index class in the Modern Street Hemi Shootout races, but when the air got bad, he struggled to run, the preferable, slightly below 9.50 in his 3,100 lb car. He also noted that it seemed to be performing about like our Race Spec 700+ (about 715 HP) engine in Mark Dudley, Jr., the Bracket Assassin’s Duster.
He asked if we could take a look at it on the dyno, which we did and the baseline runs showed it was indeed making right about 715ish. With some tune up changes we got it to 744 but studying the data and a run up higher with an airflow meter confirmed, it was going into valve float. The culprit a combination of very good parts that don’t work well together, heavy adjustable rockers with a hydraulic cam and lifters.
The two ways to address it were go back to lighter stock rockers or stay adjustable, change the valve springs, make solid his lifters, and go with a cam that is essentially our solid Mach 4 grind, we chose the later. Along with that, the heads were freshened and we told him our testing indicated a bigger CFM 4500 would help.
Great teams produce great results and today on its first baby pull, it was clear the changes made would work as it hit 801 HP. Some tuning and timing and we were able to safely get it to 830-840 HP.
Brian and his unique and beautiful Cutlass now have about 120 more HP to play with, and who knows, the next race he might have to double enter in the 9.00 index and 9.50 index class.
Another great day working with the Band of Hemi Brothers / Sisters, helping make G3 Hemi dreams come true.
Onto the big Mopar event in Norwalk, OH tomorrow at that fantastic facility, to do more of the same AND eat ice cream, lots of it.
