scrappie

Planning on converting my 71 442 conv. to a 4spd. down the road. I have been gathering all parts before hand. Is there a difference between intake manifolds for auto and MT cars?

joe_padavano

In 1971, yes there is. The MT cars used an intake with the PCV valve in the manifold behind the coolant crossover. This is the same location as the W-30 intakes, but the MT intake was cast iron, not aluminum. Casting number 407567, code letter R. These are pretty rare. Unless you care about complete correctness, you can use your current intake.

scrappie

Thanks Joe, So if I were to find the correct intake what would I do with the PCV valve inlet in the valve cover?

scrappie

Now that I think about it That is probably were the PCV valve hose connects instead of carb? right?

joe_padavano

The MT cars had two breathers, both going to the air cleaner.

scrappie

I understand the difference now. Why did Olds design it two different ways? Was it a vacuum thing or performance?