This palindrome by Joyce Johnson won a competition in the New Statesman in 1967. It has 126 words and 467 letters:

 

Headmaster's palindromic list on his memo pad

Test on Erasmus

Deliver slap

Royal: phone no.?

Ref. Football

Is sofa sitable on?

XI – Staff over

Sub‑edit Nurse's order

Caning is on test (snub slip‑up)

Birch (Sid) to help Miss Eve

Repaper den

Use it

Put inkspot on stopper

Prof. – no space

Caretaker (wall etc.)

Too many d––  pots

Wal for duo (I'd name Dr O)

See few owe fees (or demand IOU)

Dr of Law

Stop dynamo (OTC)

Tel: Law re Kate Race

Caps on for prep

Pots – no tops

Knit up ties ('U')

Ned (re paper)

Eve's simple hot dish (crib)

Pupil's buns

T-set: no sign in a/c

Red roses

Run Tide Bus

Rev off at six

Noel Bat is a fossil

Lab to offer one 'Noh' play – or 'Pals Reviled'?

Sums are not set