A deadly subway crash a generation ago is still being felt today.

A speeding J train plowed into a stopped M train on the Williamsburg Bridge in 1995, killing its operator and injuring more than 50 riders.

To improve safety, the MTA cut the 50 mph speed limit on straight track to 40 mph and modified signal systems to automatically trigger the brakes on speeding trains, even if the track ahead is clear.

But now, with a system plagued by delays, the MTA is looking at reversing at least some of those changes.

"What has been the impact now, the rolled-up impact on subway punctuality, on subway performance of the various signal changes that were made post the 1995 Williamsburg Bridge crash," said Andy Byford, president of New York City Transit.

On Monday, Byford said officials have so far looked at 37 sites in the subway where signal timers effectively slow trains.

"What could we do to now, with the benefit of hindsight, maintain the safety benefit, but is there a way of mitigating the impact upon subway performance, capacity, and puntuality and reliability?" Byford siad.

The pledge came after a Village Voice article highlighted how the signal modifications made in the wake of the 1995 crash had slowed trains.

Even though Byford says no changes to speeds will be made without significant input from transit workers, the Transport Workers Union has already declared the idea a non-starter.

Union chief Tony Utano said he will fight any rule or procedural change that would "put track workers at greater risk of being injured or killed.

Track workers Marvin Franklin and Danny Boggs were fatally struck by trains within days of each other in 2007, leading to even more safety procedures.

Byford said keeping workers and riders safe is the MTA's top priority.

"Before anyone says, 'Oh, hang on a minute, he's putting production before safety,' no I'm not. I'm a former safety director. I would never do that," he said.

Riders NY1 spoke with said they're open to faster trains if it means speedier service.

"Helps us commute faster, you know? We get to our destination faster," said one commuter.

"If you speed it up, it's good for the people who want to get there fast, but it's always about safety," said another.

There is no timetable for when the MTA will complete its study of whether to make the signal and speed limit changes.