After a cameo appearance from SSR the Nurburgring last year, Porsche made its full DTM debut last weekend with a trio of 911 GT3 Rs fielded between Schlund's outfit and Team Bernhard 75.
But the German manufacturer's weekend started poorly in Saturday qualifying, with Dennis Olsen the fastest Porsche in a lowly 19th spot - seven tenths off the pace of polesitter Mirko Bortolotti's Grasser Lamborghini.
DTM's Balance of Performance partner AVL RACETECH quickly intervened after qualifying to hand Porsche a 20kg weight reduction, which aided Olsen's rise to fifth in the race, while team-mate Laurens Vanthoor took eighth from 26th.
The best Porsche in qualifying for race two was Vanthoor in 11th place with a time that was 0.416s down on Audi driver Nico Muller's pole lap, while in the race itself he finished seventh.
However, Schlund still wasn't completely satisfied with the BoP, calling for more changes to be made in the run-up to the second round at the Lausitzring later this month.
"We traveled to Portimao full of anticipation," said Schlund.
"Unfortunately, we weren't ranked correctly in terms of BoP, which took away our chance of a podium. I see a need for action here for the next races.
"Nevertheless, I am satisfied. The team got along well and did a good job. We keep working and do our best to be perfectly positioned for the next rounds."
The Porsche 911 GT3 is the least powerful car on the DTM grid, with its flat six-cylinder motor only capable of delivering 520bhp. It also appears that Porsche bluffed the least of any manufacturer during the BoP classification test, meaning others were able to find more time as the weekend progressed.
While the Porsche did gain time over its rivals in corners, it was still lagging behind in terms of top speeds, which particularly hurt drivers while battling for positions.
Vanthoor admitted that he had to give Sheldon van der Linde "a quick nudge in the back" entering Turn 1 to pass the BMW driver for seventh in the second race of the weekend.
Van der Linde topped the speed trap at Portimao after clocking 272km/h on the start/finish straight, while Vanthoor could only reach 261.5km/h on the same section of the track.
"That was the only way to get past him," Vanthoor told Autosport's German language sister site Motorsport-Total.com.
"We were on better tyres after Saturday. Even if you made up a lot [of time] coming out of the corners, he just drove away from you every time.
"We were better on the brakes, but not that much better now. We had to try that the hard way.
"He thought it was okay. It was going back and forth a bit before that.
"I said to Sheldon, 'Sorry, but without touching you lightly, I would never have passed in my life'. He just laughed then too.
"It's very frustrating when you're trailing and there's nothing you can do.
"You try everything, but against engine power, it is the way it is. We are strong on the brakes."
Vanthoor refused to comment about the BoP situation at Portimao, but was confident that Porsche will soon be able to contend for its maiden victory in the DTM.
"The bottom line is that we're new to the DTM and we're learning every time we go out on track," the Belgian said.
"We're also improving a lot. I expect us to be fighting for victory in a couple of weekends.
"As long as we don't get everything 1000 percent right, we don't need to grumble about anything else."
