Seff

I'm trying to calculate the optimum intake for different applications, and for this I need the intake runner length and cross section of the existing intake runners.

The project car is a SBO, so any SBO intake information people might have would be wonderful. I checked the Edelbrock page and didn't really get any wiser, apart from the Performer RPM having 1.22"x1.86" port exit dimensions. Is that accounting for the 45 degree of the port or not? Hm.

Thanks.

TripDeuces

It's probably going to be pinched smaller at some point. The plenum side may be even bigger than that though so it may average out overall. I would use the info you have for the port opening as standard.
Runner length probably won't be listed anywhere so you have to rely on others with actual manifolds to measure them. Most manifolds will also have longer end runners so other than averaging the long and short ones I'm not sure how to get around that.
You'll have to compromise at some point.

80 Rocket

I have data, what do you want to know?

Seff

Trip:
An average of some kind must be expected, yes.

80 rocket:
I currently have a factory intake and a performer RPM, so an average (or enough data that I can calculate an average) runner size and length, hopefully for the normal performer as well.
I probably also need info about Iron SBO heads' intake runners - the calculation is from the intake valve to the throttle body butterflies.

This data will be used for calculations and subsequently for dyno testing on my 380 for a school project, specifically for my second semester assignment.

TripDeuces

Sounds like a cool project Seff. I assume you are in some sort of engineering program in school?

Seff

I'm studying to become an automotive technologist. Part mechanic, part project manager, part engineer, part diagnostician. Focus on performance vehicles.

80 Rocket

I have not measured any of those intakes (I hate dual planes) but have access to all 3. Did you need measurements from those? Or were you going to do that yourself?


I will check the port length on a SBO head, but generally they come in at 4.3" from the bottom of the valve seat to the intake face opening. Also, when checking runner length in the head, you measure from the intake face port opening to the inside of the plenum where the runner starts.


Are you studying harmonics in the intake pulses? If you are, the way I gave you to measure is the way you want to check it.


Sounds like a cool project, good luck.

Seff

I'd like runner lengths and dimensions of all of them, if it isn't too much trouble. I'm going to calculate all the different intakes (single planes as well if you have info), and test the ones I have on hand.

I don't know anything about impulses yet - I suppose I will?