The 358 sprints made their season debut at the track on Friday night and Glenndon Forsythe picked up the victory worth $1,500.
A rain delay of more than an hour hampered the event but it also made for scorching speeds as the night wore on.
Dewease started fourth in the 25-lap sprint car field but fell back a spot on the first lap thanks to Robbie Kendall.
Meanwhile polesitter Chad Trout streaked away with the lead over Anthony Macri and Freddie Rahmer.
However Rahmer was racing wounded thanks to a missing inside front wing panel stemming from an opening lap mishap on the initial start that also would end up claiming Danny Dietrich.
The only caution flag of the race unfurled for Dietrich on the third lap thanks to a collapsed front end, likely due to the initial start mishap.
Rahmer began slipping as the laps strung together and Dewease was able to get around him for fourth on the seventh tour before taking third with nine away.
But the pace was quick on the soft, moistened clay and it took all that Dewease had to run down the front duo of Macri and Trout.
But steadily, he honed in on Macri for the second spot and using surges of speed at the end of the backstretch to blast across turns three and four, he overtook Macri with seven to go before going to work on Macri.
Upon taking second spot, Dewease trailed the leader by 1.5 seconds and it would take him another five laps to catch Trout and get command before then pulling out to a 1.2 second victory.
Track conditions forced Dewease to use all the muscle in his car and in the cockpit to get the victory as he stated in victory lane, seemingly worn thin from the grueling speed just endured.
The win was the 94th of his illustrious career at the Williams Grove oval.
Trout rode home second followed by Macri, Kendall and Rahmer.
Sixth through 10th went to Lucas Wolfe, Brian Montieth, Cory Haas, Rick Lafferty and TJ Stutts.
Heats went to Dewease and Dietrich with the dash going to Trout.
Dewease set fast time with a lap of 16.634 seconds.
Forsythe wired the field for the 20-lap win in the 358 sprint feature checkers.
He raced ahead of Matt Findley the entire way but while holding a healthy lead most of the race, his advantage slipped away during the final five laps as his mount struggled to get off of the corners with speed.
Troy Wagaman Jr. rode home third followed by Doug Hammaker and Kevin Nouse.
Sixth through 10th went to Rodney Westhafer, Jeff Halligan, Rich Eichelberger, Kyle Denmyer and Todd Rittenhouse Jr.
Heats went to Denmyer and Westhafer.
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410 sprints, 25 laps: 1. Lance Dewease, 2. Chad Trout, 3. Anthony Macri, 4. Robbie Kendall, 5. Freddie Rahmer, 6. Lucas Wolfe, 7. Brian Montieth, 8. Cory Haas, 9. Rick Lafferty, 10. TJ Stutts, 11. Kyle Moody, 12. Steve Buckwalter, 13. Adrian Shaffer, 14. Dylan Cisney, 15. Troy Fraker, 16. Ryan Smith, 17. Danny Dietrich, 18. Mark Smith
DNS: Kody Lehman
358 sprints, 25 laps: 1. Glenndon Forsythe, 2. Matt Findley, 3. Troy Wagaman Jr., 4. Doug Hammaker, 5. Kevin Nouse, 6. Rodney Westhafer, 7. Jeff Halligan, 8. Rich Eichelberger, 9. Kyle Denmyer, 10. Todd Rittenhouse Jr., 11. Chris Frank, 12. Dwight Leppo, 13. Gregg Foster, 14. Jacob Galloway, 15. Troy Rhome, 16. Scott Fisher, 17. Brett Wanner
DNS: DJ Montgomery