Lines claimed the 30-lap final from Veal, Californian Kyle Hirst and local drivers Brad Maiolo and Daniel Harding.
The championship went down to the final between Veal and defending champion Brooke Tatnell who finished eighth.
Polesitter Luke Dillon was out of the race before it started, pulling infield with an ill-sounding engine, promoting Harding to the front row with Lines.
Harding took advantage of this to be the early leader until he was passed by Lines on lap 15.
James McFadden forced a restart only four laps in after he pulled up on the main straight, before resuming from the rear.
Jason Kendrick, who started from P4, was running third until he withdrew to the infield on lap 10.
After Harding surrendered the lead he was under immense pressure from Veal, then Hirst and then Brad Maiolo as they ran deep into lapped traffic.
Maiolo finished fourth after starting from P8, putting in another solid drive and banking some serious points in the AHG Sprintcar Championship that has one round to run.
Dave Murcott finished sixth (after starting fifth), ahead of national champion Kerry Madsen (who charged through from 15th), Tatnell, Shaun Bradford (from ninth), Ryan Farrell (from P16), Jamie Maiolo (from P12), Lee Nash, Ryan Jones, McFadden, Carl Dowling, Kye Scroop and Lynton Jeffery.
Earlier in the night heat race wins went to Dillon, Kendrick, Lines, McFadden, Milling and David Priolo.
Madsen recovered some ground after his Friday night crash by winning the B Main and getting the transfer to the final, along with Farrell, Scroop, Jones, Jeffery and Milling.
David Priolo suffered heartbreak after his motor let go with one lap remaining in the B Final when he was in a transfer spot.
Saturday night results:
Hot Laps 1: Luke Dillon 14.886, Jamie Veal 14.942, Carl Dowling 14.981, Steven Lines 15.102, Dave Murcott 15.144, Brooke Tatnell 15.186, Shaun Bradford 15.274, Jason Kendrick 15.318, Daniel Harding 15.494, Bradley Maiolo 15.509, Kyle Hirst 15.588.
Hot laps 2: Kerry Madsen 14.205 14.203, Lynton Jeffrey 14.318, Ryan Farrell 14.453, Ryan Jones 14.463, Ben Ellement 14.491, James McFadden 14.500, Troy Lawson 14.787, Jamie Maiolo 14.801, Lee Nash 14.839, Jake Beard Miller 15.087. NTT James Inglis and Kye Scroop.
Hot laps 3: David Priolo 13.838, Ryan Lancaster 14.289, Daryl Clayden 14.479, Jason Pryde 14.687, Andrew Priolo 14.705, Taylor Milling 14.712, Scott Chatwin 14.764, Aldo De Paoli 14.982, Mitchell Wormall 15.299.
Heat 1: 1st Luke Dillon, 2nd Daniel Harding, 3rd Dave Murcott, 4th James McFadden, 5th Kerry Madsen, 6th Kye Scroop, 7th Carl Dowling, 8th Taylor Milling, 9th Mitchell Wormall, 10th Jason Pryde. DNS: Ryan Jones.
Heat 2: 1st Jason Kendrick, 2nd Jamie Veal, 3rd Kyle Hirst, 4th Lee Nash, 5th Jamie Maiolo, 6th David Priolo, 7th Ryan Farrell, 8th James Inglis, 9th Andrew Priolo, 10th Scott Chatwin, 11th Lynton Jeffrey.
Heat 3: 1st Steven Lines, 2nd Bradley Maiolo, 3rd Jake Beard-Miller, 4th Shaun Bradford, 5th Troy Lawson, 6th Brooke Tatnell, 7th Daryl Clayden, 8th Ben Ellement, 9th Aldo De Paoli, 10th Ryan Lancaster.4
Heat 4: 1st James McFadden, 2nd Andrew Priolo, 3rd Luke Dillon, 4th Jamie Veal, 5th Mitchell Wormall, 6th Jamie Maiolo, 7th Daniel Harding, 8th James Inglis, 9th Jason Pryde. DNF: Ryan Farrell.
Heat 5: 1st Taylor Milling, 2nd Daryl Clayden, 3rd Kye Scroop, 4th Kerry Madsen, 5th Troy Lawson, 6th Dave Murcot, 7th Shaun Bradford, 8th Steven Lines, 9th Carl Dowling, 10th Jake Beard-Miller.
Heat 6: 1st David Priolo, 2nd Brooke Tatnell, 3rd Ryan Lancaster, 4th Lee Nash, 5th Bradley Maiolo, 6th Jason Kendrick, 7th Kyle Hirst, 8th Lynton Jeffery, 9th Aldo De Paoli, 10th Scott Chatwin.
Bronze Dash: Luke Dillon 13.233, Kyle Hirst 13.244, Jamie Veal 13.337 and Bradley Maiolo 13.342.
Silver Dash: Luke Dillon 13.171, Steven Lines 13.294, Dave Murcott 13.340 and Kyle Hirst 13.353.
Gold Dash: Luke Dillon 13.157, Steven Lines 13.219, Daniel Harding 13.350 and Jason Kendrick 13.363.
B Main: 1st Kerry Madsen, 2nd Ryan Farrell, 3rd Kye Scroop, 4th Ryan Jones, 5th Lynton Jeffery, 6th Taylor Milling, 7th Troy Lawson, 8th Daryl Clayden, 9th James Inglis, 10th Andrew Priolo, 11th Mitchell Wormall, 12th Aldo De Paoli. DNF: David Priolo, Jake Beard-Miller, Jason Pryde, Ryan Lancaster and Scott Chatwin.
A Main: 1st Steven Lines, 2nd Jamie Veal, 3rd Kyle Hirst, 4th Bradley Maiolo, 5th Daniel Harding, 6th Dave Murcott, 7th Kerry Madsen, 8th Brooke Tatnell, 9th Shaun Bradford, 10th Ryan Farrell, 11th Jamie Maiolo, 12th Lee Nash, 13th Ryan Jones, 14th James McFadden, 15th Carl Dowling, 16th Kye Scroop, 17th Lynton Jeffery: DNF: Taylor Milling, Jason Kendrick. DNS: Luke Dillon.