What is Toji's "accent"?

Question

I was reading a scanlation of the Evangelion manga and noticed that Toji consistently uses a lot of informal-sounding speech. I chalked this up to poor translation quality — I tend to find this sort of thing distracting — but when I read a licensed translation to English, I encountered a similar form of speech; for example, from ch. 20:

Ikari! Yer not allowed ta look!

Later, Asuka accidentally provokes someone at the arcade. Someone, possibly Suzuhara, tells Toji to talk to the angered man because both have the same "accent". Thus, it seems unlikely that Toji's language is similar to, for example, Shinji's, when he asks Toji "Whadda mean?" after being asked about his exchange with Rei in the same chapter. In other words, it does not sound like Toji's habits fall within the "normal" bounds of variation in how people are supposed to talk.

What is this "accent"? What is Toji's language supposed to correspond to in the Japanese original?

Answer 1

According to this quite old Ask John column, Touji's accent in Japanese is Osaka-ben.

Ask John: What’s the Significance of the Osaka Accent?

Question:
Looking at several anime series, and translated Tokyo TV broadcasts, I am puzzled over the references to the Osaka region. In Cardcaptor Sakura, Kerberos speaks with an “Osaka” accent, and in Battle Athletes Victory, Itchan speaks an Osaka dialect. What makes the Osaka region unique, and how does the rest of Japan view the region? Is it like how California (the land of fruits and nuts) is viewed by the rest of the US?

Answer:
Beside the examples you’ve mentioned, a few other anime characters that speak with an Osaka inflection include Li Kouran of Sakura Taisen, “Kitsune” Konno and Koala Suu of Love Hina, Tasuki of Fushigi Yuugi, Kiiro Iijima of Iczerion, Nicholas Wolfwood of Trigun, Tarta and Tatra of Rayearth, Matsuko and Shige of Tonari no Yamada-kun, Touji Suzuhara of Evangelion, Ten from Urusei Yatsura, Tomoko Hoshina of To Heart, Momiji of Yamamoto Yohko, and Aiko of Ojamajo Doremi.

You can see in the second paragraph that Touji is listed as a character who speaks with an Osaka accent.

Eva wiki and TV Tropes corroborate this. According to the wiki, the accent Touji speaks with in the English manga was supposed to be a New York/Brooklyn accent, which was also used to translate Osaka's accent in the Azumanga Daioh manga. In Abenobashi Mahou Shoutengai and many other shows, a Texas or Southern accent was used.

Answer 2

It's Kansai dialect (Kansei-ben), also called Osaka dialect (Osaka-ben). Everything is a bit different, but you can generally grasp what they are saying, so there isn't really any need to have him talk to the guy. In the first place, people with this dialect always speak like that anyway, so if it was like that nobody would be able to understand Touji.

It's like American and British English. With American being the Kansai one. So it's like a British guy asking an American friend to talk to the angry American.