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Hello world!
I'm new here so please don't get mad at me for asking.
What i need, and i hope some of you know this is the  CAM timing for the RB26DETT engine.
More specific i need:

the angle at witch the intake valve opens

the angle at witch the intake valve closes

the angle at witch the exhaust valve opens

the angle at witch the exhaust valve closes

Lobe Separation Angle

and the advance.

All i know by now is: camshaft duration 240°in, 236°ex lift: 8.58mm in, 8.28mm ex

I can't find anywhere the data that i need and i can't determine it either.
I've attached a photo with the stock camshaft.
All of this is for a school project, i currently study Automotive Engineering and i would like to simulate the RB26DETT engine.
Thank you very much!

 

valve timing.PNG

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4 minutes ago, Ben C34 said:

From the above info you can calculate it.

But..... At what valve opening are those figures?

It is probably going to be heaps easier to get the specs of aftermarket cams.

Hello Ben!

After posting I found a topic in this forum and I got the data I needed. I just want to confirm it.

Stock cams

Intake 240 degrees 7 BTDC 53 ABDC 113 degrees

Exhaust 236 degrees 63 BBDC 7 BTDC 118 degrees

Sounds like an interesting project.

I don't have the figures to confirm, but in our production car racing we have the cams measured before being sealed into the engine. The measuring is done by Camtech in Sydney, so they must have the data you are after for the stock cams.

The full details for RB26 cams have been listed on the 'net about 60000000173746454 times over the last 30 years. It just takes 10 minutes of googling to get a consistent set, cutting out the clearly wrongheaded ones.

But as Ben said, you can get all of what you need from the data in your first post. If you are doing "Automotive Engineering" to the level that you are going to run an engine in a simulator, I find it very hard to believe that you do now know the relationships between seat to seat duration, advertised duration, lobe centre angles and the timing of specific events. All of these are simply obtained with arithmetic from each other. You only need ~half of them to get the other half. The one caveat there is that the finest details are somewhat affected by the valve clearances.

I would suggest that in the context of running it in an engine simulator, precise details are only going to have a small effect on the quality of the simulation anyway. People put far too much faith in the output of computer simulations.

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