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Discussion Starter #1
Can anyone tell me off the top of their head what angle a nord engine is canted over to the left?

Or: Can someone please measure this on an engine sitting on the ground or in a car with nice healthy engine mounts?
 

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Discussion Starter #3
Thanks. I make it at about 4 degrees to the left.

Can anyone verify that?
 

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Trained (ex)Professional, , 1953-2018 RIP
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I read somewhere that it was 7 1/2 degrees. Can't verify that though. Nor for which model.
 

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Didn't the angle vary depending on the particular installation? Giulietta Veloces being more canted than Normales, TZs being an extreme?

Andrew
 

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As Andrew suggested, the cant varies with the particular model in question. I believe he is also correct in that the TZ was an extreme. I once had a nice ported intake manifold that "wouldn't fit anything" back in the early 70's. It was for a TZ. Wish I still had it today!
 

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Discussion Starter #11
Thanks a lot guys. I will take it as 5 degrees. That is as accurate as I need it to be.

Anyone curious why I wanted to know???

I am building a new set of headers for my mates historic touring car (105 GTV 2000). It has some dodgey thing that has all the exit angles all over the shop and incorrect primary lengths (for a 4-1 exhaust).

I am building a set of headers that will have a flange at 18" after the head. After the flange I am going to have a two options, a continuation of the 4 primaries for another 18" and then into a 4-1 collector, and the other option: merge the 4 primaries into 2 secondaries for 24" then merge into 1. This section will be able to be changed depending on requirements.

When I have built this system, I will dyno the car with present system, and the two different configurations. If I get good results (wouldn't want to embarrass myself, would I...), I will post charts ;)

Wanting to get it right, I thought I would measure everything up and draw it all up on CAD (have to anyway, to get the flanges laser cut). This way, I can also find out difinatively what angle the primary pipes should exit from the head....

As the exhaust port is actually tapered from the guide area out, I have used the central axis of the port for my drawings. And so by my measurements and drawings, the primary pipe should exit the head at an angle of 14 degrees down from the horizontal (the angle of the axis of exhaust port in an installed engine). Of course this is the actual exit angle at the flange face. I am not going to speculate on how far this should continue before arcing in whatever direction is necessary suffice to say that the ideal is a straight piece of pipe.... Nor would I speculate on what effect a divergance from this angle would have on the effectiveness of a set of headers.

For obvious reasons, even if the pipe was at the right angle, the full advantage of getting this right can be negated somewhat if the inside diameter of the flange is not cut to match this angle of the port. Elementery stuff, but actually not that easy to practically achieve for a few reasons that are easy to see when you draw it all up.

So, next time someone tells you their exhaust (on a nord) has the dux gutz as far as headers go, just get out your protractor and see how close this angle is...

Will post pictures of the system as I make it.
 
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