Some report pinning, which usually due to low octane or incorrect timing/ advence.
. A 351 cubic inch motor with flat top pistons will achieve 10:1 compression ratio with quench chamber heads having 63cc combustion chambers and standard 0.035" deck clearance. However 10:1 compression ratio can...
You might be right on him having CJ cam. Acording to Autolite publication from 70s, CJ cam (Or ford performance can as it was named before CJ existed)
gain 65 hp on M code.
This guy dynoed 70 M spec 351c, claming just a refreshed engine - but who knows about cam. But peak power is at 5,100rpm, which ineicates milder cam then CJ. 650 carb.
He said they put those pistons to get to factory spec of 11:1 compression. He must not know that compression as advertised was not true. Also he was in route to make it boss spec ... and he did later on ( he tested all high ho small blocks at factory soec - 351c won, boss spec)
I see that all years mustangs had inconsistent heads volume and the true measurement will vary by car. They are all lower in compression then advertised by roughly same amount.
CJ heads varies (76.9cc - 79.9cc)
End of the day, throw CJ/ford performance cam (as it was referd to in 1970) and...
Make sensce, M does not have a cam to rev. and will feel maxed out.
As far as 4 bolts, drag races saw no need for them, maybe road racing abow 8k they wiuld be of a benefit.
Because of misleading Ford advertising - they slapped CJ on detuned engine just to sell cars.
71 Q is rare, so i can see it bring more money justlike 72 HO R code.
They all can make similar power once you throw equivalent pistons and heads in the detuned engines.
Performance wise (stock or...
OK, after some more search i found information in atomobile-catalog. Hopefully its correct
Horsepower gross:
212.5 kW / 289 PS / 285 hp (SAE gross)
/ 5400
Torque gross:
502 Nm / 370 ft-lb
/ 3400...
71 M code being overshadowed by other models and i cant seem to find factory power rating for, for torque.
70 M is 380 ft.lb and since 71 ratings been degraded abit for HP (posibly due to insurance) i would guess around 360 ft. lb. for torque.
Curious to see how much more torque it has...