F7R Port geometry

[Lanky]

Just curious for my own interests and calculations....does anybody have the inlet port length for F7Rs?

Port length in definition being from the inlet valve back up to the manifold face of the head. Not with a straight rule either!....

What's much more difficult to measure is also the runner length of the manifold (that coil of a beauty of a thing..)....if anyone has this from a renault tech sheet or something it'd be a great help.

Also if anyone knows of the port size and where its minimum is (ideally for each separate valve port and the geometry before they split). Don't want to be pulling off the plenum if I don't have to.

Cheers all.

 

[Chris H]

only issue with that is the renault heads manifolds compensate of the runner length difference on the floor of the port

as for the lengths dunno, I just work the heads never measure as its obvious what you need to do with them.

 

[Lanky]

Only curious to fix some boredom while at work really.

I suppose i could look at the manifold in a little more detail but with the shape and design of it i'd have thought they'd have managed to match the runner lengths quite well. Would be interesting knowing the length so can then see what order they aimed for at the peak torque speed.

When i've truly ran out of things to do one day i'll probably whip the mani off and get some thick solder wire out and gauge it. For port length for time being i bet 80-90mm is a safe guess?

 

[Chris H]

maybe a bit more than that.

The runners are quite long when you think how they curl round to the plenum

 

[Lanky]

maybe a bit more than that.

The runners are quite long when you think how they curl round to the plenum

No, port length i.e. valve up to the machined manifold face of the head. As if the mani wasn't there.

yeah with the curl i estimate an average 175mm diamater, gives you about 550mm runner length. Then total id add that to port length.

 

[Chris H]

yes i said a bit longer than that went onto the separate topic of the manifold runner length which is quite lengthy

 

[Lanky]

I did a search for previous topics, didn't see anything immediate come up...?