Over a short but significant period in US Top Fuel drag racing history, the Surfers Team set record level performance. The Surfers Team was made up of owners/builders/tuners, Bob Skinner & Tom Jobe with driver/crew member, Mike Sorokin. Their nitro Chrysler (early) Hemi dragster quickly became one the sport’s best performers. Highlights of their setup along with tuning secrets were reported by author, Dave Scott in the June, 1966 issue of Popular Hot Rodding magazine.
Dave reported the following: engine size @ 392 ci; CR @ 7.5 to 1 (higher than most); nitro mixture @ 97% nitro (higher than most) + 2% benzol + 1% secret anti-detonate; 6-71 Roots blower @ 22% OD; magneto advance @ 36 deg.; fuel pump, Hilborn PG 175; hat nozzles recommended to start out with @ 0.062 inch dia.; port nozzles @ 0.085 inch dia.
Nitro Tuning Secrets
One of the tuning tips was a secret anti-detonate. Another was a fuel injection trick. That was the fuel split between the blower hat and manifold nozzles. The nozzle sizes recommended by the team to start out with were shown above. This results in a 34-66% fuel split between the hat and manifold nozzles. The feature article suggests that the team actually ran a lot more fuel going above the blower. The trick was moving more fuel to the hat nozzles for blower sealing & intake manifold cooling. That trick was accomplished from an unnamed combination of larger hat nozzles feeding the blower and smaller manifold nozzles below the blower. The actual jet size combination that was run was secret. The author, Dave Scott, speculated a 75-25% fuel split from an analytical discussion with the Surfers team in the article.
ProCalc Nitro Nozzle Analysis
Using Pro-Calc, we calculated a hat nozzle size of 0.091 inch dia and a manifold nozzle size of 0.052 inch dia. That combination provides about the same air to fuel ratio and fuel pressure as the nozzles previously suggested. Both combinations were compared to what other teams were doing at the time and produced similar air to fuel ratio and fuel pressure values. Fuel split with this latter combination is 75-25%. So that may be the secret or at least close to it.
Surfers Nitro Racing Success
Best performance for this national event winning dragster was reported at 7.34 Sec. ET at 210.76 MPH in 1966 that was close to the best all time performance up to that time on 11 inch wide racing tires. During the short era of competition, the team was noted for a dramatic nitro R&D effort that yielded a most consistent level of performance. They achieved winning performance with little parts breakage. Dave Scott’s article reported that the secret anti-detonate made it possible to run very high percentages of nitro with compression ratios that were higher than most. Both of those were with little damage that was considered a significant achievement by the team.
Similar Fuel Split Success in Blown Methanol Racing Records
We presented information in our methanol racing fuels manual about performance gains from fuel split. Steve Woods who ran winning performance levels in nostalgia AA/GS with a record setting blown alcohol combination is pictured in both our fuel injection manual & methanol manual. Fuel split in Steve’s combination was similar to the speculated values for the Surfers. Steve reported better performance with more fuel above the blower.