Quick measurement?

[djb25]

Hi everyone,

I'm converting my 2.7 to EFI, and I'm currently in the process of building a new intake for the car. I'm trying to keep the existing CIS system intact (and also on the car until the EFI is ready to install).

Anyway, if someone has a 911 engine sitting around without the intake on it, I need two quick measurements:

1) From cylinder to cylinder, across the engine (say from #3 to #6) and

2) Either a triangulation of the intake studs, or a measurement of the angle from one stud to another.

I know my descriptions are terrible, I wish I could find a drawing showing... exactly what I'm looking for.

If I find one, I'll post it.

One other question - would the exhaust ports/studs be the same as the intake? If they are, I could just take the measurements myself...

- Damion

[Duane V]

Hi Damion
I believe the stud angle is 65 degrees.
What are you planning for an intake and ECU?

Cheers
Duane

[2.7RACER]

Damion,
The center to center dimension of the intakes is 118.4 mm.

edited for wrong numbers. 118.4 mm as measured.

[djb25]

Thanks guys, much appreciated.

I'm using megasquirt (I've had the ecu for about two years now, I can't remember what version it is) and for the intake I'm just going to use CIS runners and a fabricated aluminum center with a throttle body from a 944.

[2.7RACER]

Damion,
The above numbers are wrong. Sorry, I just measured the center to center of my 2.7 intake and got 118.4 mm. I'll get you the angle once I have it figured out.

118.4 mm is center to center of adjacent cylinders.
You asked about center to center across the motor.

It pays to read the question and understand it. My bad.

I measured across studs at cylinder 2 to cylinder 5 and got 19-5/16". The case vent interfered with a 3-6 measurement.
1-4 measured the same 19-5/16". This is an angle since these cylinders are offset from each other.

19-5/16" is a center to center dimension of the intake ports.

Measuring 90 degrees from the case centerline to the nearest stud was 8-1/4"
This is not center to center, it is case centerline to the inside stud edge.
To get the center from the case centerline add 1/2 the stud dia. plus 1/2 the height of the triangle formed by the stud angle. S/B (1/2 (7.3mm + 59.6mm))=33.45mm.
33.45mm = 1-5/16" plus 8-1/4"= 9-9/16" from case centerline to intake center.

Bottom line the relationships are all angles due to the offset of the cylinders to each other.

My calculations checked two ways for the angle of the intake studs was 64.6 degrees from the case centerline.

I would lay all this out carefully and then build to fit the layout.
Too many angles and conversions.

[djb25]

Thanks Doug - this will be a huge help!

Hopefully once I lay this all out I can either scan my drawing or draw something on the computer and post it on here for future reference (for the masses).

Once again, thanks a million - you have no idea how much of a help these measurements are to me!

- Damion