I have a #'s matching 1973 454 4 spd m21 Chevelle SS very rare only 600 made, have build sheet original colors.Older resto still take to shows. Just about 400 miles since resto done around 2000, all stock down to hose clamps, need to sell, $21000 obo Leave # i will call you back thanks Ken.
I wonder why it would have a M21 behind a smogger motor?
Ray?
M21 optional until 1975. Only 8 454 M21 made there way out of Oshawa plant in 1973. I have documents at home. Although most people forget 1972 was the first year for lower compressions and Net HP ratings and in addition to being the intended first year for the colonades the drive trains were carried over pretty much intact until 1974. With onslaught of catalytic Converters in 1975 the HP really dropped.
The thing is, while the horsepower dropped, you still had a swept volume of 454 cubic inches and that delivered torque. As I recall it was 345 lbs/ft (net). Since the LS4 by then with its lazy ignition advance curve (done for smog control) and mild camming & valve spring pressures, the motor did not like to rev. With all that torque, a 3.42:1 gearset out back, the close ratio trans meant less rpm drop between shifts.
The M22 was the 4-speed used with the 454 through 72, then they switched to the M21 when horspower slipped downward (the M22 was also dropped due to noise standards).
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67 Chevelle Malibu Sport Coupe, Oshawa-built 250 PG never disturbed.
In garage, 296 cid inline six & TH350...
Cam, Toronto.
I don't judge a man by how far he's fallen, but by how far back he bounces - Patton
Cam I have the torque at 360 in everything in 1973 except Corvette which was 380. Regardless of the actual number that kind of torque can not be denied. Net HP ratings started in 72 and is due to GM changing to 85 degree factor versus 60 degree used prior. Mathematically that 1973 454 had 245 NET Hp which is 330 Gross HP.
'64 Parisienne CS "barn find" - last on the road in '86 ... Owner Protection Plan booklet, original paint, original near-mint aqua interior, original aqua GM floor mats, original 283, factory posi, and original rust.
only car that ever beat him, was a 454 lemans from Ontario
Funny, that must be slow as I remember beating a 454 LeMans a while back with my 351 Mustang....
Huh You must have been dreaming.
I had a dream about a 351 Mustang that entered the highway 20 car lengths ahead of a 454 LeMans, then the Mustang Driver dropped the hammer. By the time the LeMans driver entered the highway the Mustang was 30 cars ahead but the LeMans reeled him in AND he didn't have the correct length throttle cable so the carb couldn't open fully.
-- Edited by 73SC on Sunday 6th of May 2012 12:15:03 AM
May have reeled him in, but did he ever pass the Mustang? Perhaps the Mustang was so far ahead he thought to slow down so the LeMans could catch up.....
The thing is, while the horsepower dropped, you still had a swept volume of 454 cubic inches and that delivered torque. As I recall it was 345 lbs/ft (net). Since the LS4 by then with its lazy ignition advance curve (done for smog control) and mild camming & valve spring pressures, the motor did not like to rev. With all that torque, a 3.42:1 gearset out back, the close ratio trans meant less rpm drop between shifts.
The M22 was the 4-speed used with the 454 through 72, then they switched to the M21 when horspower slipped downward (the M22 was also dropped due to noise standards).
I believe some M-22's made their way into 73 model year cars
couldn't hear it for the whine of the wife...
You must have been dreaming.