Charlie Oakwell-Boulton gave the hosts the lead, heading in the opener on 26 minutes, and an upset looked on the cards when new boy Miles Everett doubled the advantage just before the break.
The tie turned however, as Invicta, one step above Chi in the non-league pyramid, snatched two goals in three second half minutes. Both Ade Yusuff and Ian Draycott went on to bag braces with Jordan Wright adding a fifth, before Ollie Barry pulled one back for Chichester late on.
Eight players who started for Folkestone against National League Wrexham in the fourth round of the FA Trophy last time out featured in the Kent team’s strong line-up, whereas Miles Rutherford & Co opted for a much-changed side to the one that beat Three Bridges at the weekend.
U23s keeper Ollie Carroll came in for custodian Kieran Magee between the sticks, youngsters Jack Farrier and Eric-Georges Dellaud replaced Ryan Davidson and Rob Hutchings as full backs, Tyrone Madhani started in midfield alongside recent signings Everett and Stan Bridgman, who caught the eye, together with Oakwell-Boulton. Regular first-teamers Ben Pashley and Lewis Hyde were partnered in the heart of defence, and City stalwart Scott Jones was given the No9 shirt. Top scorer Callum Overton and skipper Jamie Horncastle dropped to the bench with other U23s Cam Russell, Liam Conolly and Barry.
The visitors pressed early on and forged a couple of decent opportunities, but Draycott’s first minute effort did little to trouble Carroll, and then when the Chi No1 failed to clear the ball it wouldn’t sit up for striker David Smith.
Next, Ronnie Dolan fizzed one over the frame of the goal just before Ben Mendoza was dragged down in the box following an exchange with Jones only for the ref to dismiss penalty appeals.
Jones pulled a shot narrowly wide on nine minutes after Madhani picked him out and Madhani spurned a golden chance shooting over after a lovely cross-field ping from Everett.
Folkestone then won a soft free-kick which Dolan took and a teammate looped his header onto the top of the bar.
Farrier did well to cut out Dolan’s through ball intended for Draycott just before Carroll denied the Invicta No7 on the quarter hour mark.
Madhani and Farrier hooked up down the right but Tim Roberts claimed easily enough when the delivery came in.
Alfie Paxman’s pace got the away side going on the other flank only for his cross-cum-shot to ricochet off the woodwork.
Composed defending by Farrier allowed him to control the ball on his chest and clear as Draycott combined with Smith and whipped over a cross.
And then Oakwell-Boulton broke the deadlock against the run of play with a classy header.
Invicta responded and the Chi back four had to have their wits about them to charge an effort down, clear a Wright delivery, and smuggle the ball to safety as Smith and Paxman threatened once more.
The hosts got away with one when Farrier bailed Carroll out for a mistake and then the Chi keeper was off his line sharply to challenge Yusuff.
Folkestone won a half hour corner that Dolan took and Micheal Everitt headed into the danger area. Yusuff seemingly got a final touch but an assistant referee’s flag chalked the equaliser off.
Josh Vincent then cracked a fierce attempt that somehow cannoned back off the woodwork and home side defenders got in headers and blocks to subdue a spell of sustained pressure.
Mendoza had a shot charged down at the other end and Carroll made a fine save to deny Yusuff, while an error by his counterpart moments before the half time whistle gifted Everett Chi’s second goal after good pressing.
The visitors’ Connor Collins came on for Roberts in goal at the break and Yusuff went close seconds into the restart with an attempt which curled inches over.
Carroll then got something behind Draycott’s shot, but couldn’t prevent the Invicta player scoring in the 50th minute after nice movement drew opponents in and Draycott found the back of the net.
It was all square barely three minutes later as Yusuff stabbed home Paxman’s pass.
Next, Carroll pulled off a super double save, and Jones had a shot on the turn blocked by Paxman in a rare raid.
Dolan thumped a set-piece into the wall before Carroll brought Yusuff down in the box, only to redeem himself with an impressive save from Yusuff’s resulting penalty kick.
Russell replaced Bridgman for the last 30 and Wright gave Folkestone the lead on 64 minutes.
Carroll held on to Yusuff’s next effort, but made a mistake presenting Draycott with his second, and his team’s fourth of the night.
A lovely twist and turn by Mendoza sent Chi away for a move that fizzled out before Yusuff and Paxman linked up again and Carroll got a glove on the final cross.
A simple finish from Yusuff made it 5-2 on 80 minutes with Barry, who’d replaced Oakwell-Boulton, neatly steering in Jones’ delivery from the right for a consolation one minute ahead of full time.
Next up for Chi is a visit to Whitehawk for an Isthmian south east on Saturday 22nd January (Kick Off 3pm).
Chichester – Carroll, Farrier, Dellaud, Oakwell-Boulton, Hyde. Pashley, Bridgman, Mendoza, Jones, Madhani, Everett. Subs: (Conolly, Barry, Russell, Horncastle, Overton)