A Collection of 4 Stroke Valve Event / Cam Timing Data

[RReid]

Where to Find Stuff:
> This page - Full size, normally aspirated engines
                      Data Spreadsheet (attachment)

> Reply #1 - Full size, supercharged engines
https://www.modelenginemaker.com/index.php?topic=10726.msg247119#msg247119

> Reply #2 - Model engines
https://www.modelenginemaker.com/index.php?topic=10726.msg247120#msg247120

> Reply #10 - 2-Stroke data (for comparison)
https://www.modelenginemaker.com/index.php?topic=10726.msg247563#msg247563

> Sample diagrams and templates may be found here:
https://www.modelenginemaker.com/index.php/topic,10721.0.html

> Additional relevant information and diagrams may be found here, starting with Reply #62:
https://www.modelenginemaker.com/index.php/topic,10708.60.html



Data for normally aspirated, full size engines will be found below.
Sleeve valve engine data will be differentiated by green formatting and a slightly elliptical diagram.



https://i.postimg.cc/BnGwgjfS/350cc-Matchless-Single-Motorcycle-mild-street.jpg[/img]

[RReid]

Data for supercharged engines will go onto this page.
Sleeve valve engine data will be differentiated by green formatting and a slightly elliptical diagram.

[RReid]

Model engine data will go onto this page.
Sleeve valve engine data will be differentiated by green formatting and a slightly elliptical diagram.

[RReid]

I've opened this topic to serve as a repository for valve event timing data that forum users would like to submit. There is also a section for diagram templates and the like.

I've kicked it off by placing two diagrams, one for a VW type 1 (bug/beetle) engine with stock cam, and one for the same engine with an aftermarket Engle W110 "Sport" cam.

Anyone who wants to add data may send it to me via PM and I will add it to the appropriate section above.

This part of the topic begins the "discussion" section. Hopefully this will work out alright.

[Vixen]

Ron,

Thanks for taking on the task of assembling and maintaining this collection of 4 stroke valve event data.

Perhaps the most important section would be one relating to our model engine valve event timings. That's the reason the MEM forum exists and one where there is surprisingly little data available.

I kicked this all off with my work on Sleeve Valve engine port timing. A model engine will never have an effective supercharger unless it runs at jet engine speeds, so I was attempting to identify more suitable port timings for a normally aspirated model sleeve valve engine.

Although it may be a minority sport, I believe you need an additional section for Sleeve Valve engines which would include both supercharged and N/A engine data. You are more than welcome to add the data I have presented in Reply#62 of the Hercules saga. But note, the timing diagram relates to the sleeve crank angles rather than cam shaft angles. The 'angular scale' is shown as an eclipse because that is the path taken by the sleeve drive ball, whereas a cam shaft is best represented by a full circle. 

You are also welcome to use any of the other poppet valve data in reply #62. Or to occasionally refer your readers back to it

Cheers

Mike

[RReid]

Thanks Mike, for your support and your suggestions. It's all a bit catch as catch can this week, as I'm busy with a bunch of grandkiddos.

I've converted the third section, originally meant for storing templates, to one specifically for model engine data. AVTUR's Matchless motorcycle engine data has been added to the first section. Vixen's sleeve valve data will also be added as time allows.

[RReid]

I've added at least minimal date to each of the three categories (found at the opening of this topic). On the first page I've added a simple index, which may become more important if the category list, and the topic itself, grows longer. Finally, I am entering the raw data into a spreadsheet as I go, which I will also post as it becomes more developed.

[Vixen]

Hello Ron,

You can easily overwrite your reply#3 to make an additional category. Or you could ask one of the forum's 'mods' to add a few blank replies at the start, for you.

Mike

[RReid]

Several more diagrams have been added. Most recently is Achim (fumopuc)'s Bruce Macbeth Engine, added to the Model Engines category. Thanks Achim!

Many Thanks also to Mike (Vixen) and AVTUR.

Feel free to submit any valve event data you may have, even if it is only IO-IC-EO-EC numbers, preferable with a note whether relative to crank or to cam rotation (most published data seems to be relative to crank rotation).

If anyone has any data for an engine with atmospheric intake valves I'd be interested in that as well. I could make a guess about the intake timing for these, and that may be all the engineers back in the day had as well, but...

[RReid]

I've added a few more diagrams recently. Also I've switched from inserting the diagrams as attachments to posting them as hosted images. This change avoids the 8 attachment per page limit. I added links to the "Where to Find Stuff" list on the first page; clicking those will open the linked page in a new window.

[RReid]

This Topic is about 4-stroke engines, and I don't intend to expand the scope. However, Rick Doane graciously sent me some nice, very carefully measured data for a pair of high performance, high RPM 2-stroke model engines.  I think they are worth posting here for the sake of interest and comparison.

I will add a link to this page in the "Where to Find Stuff" list at the top.

[RReid]

I just added two new diagrams to the first page of this thread, the Normally Aspirated category.

The Curtiss OX-5 was the most widely used American aero engine of WW1, most notably powering the Curtiss JN-1 "Jenny" trainers and continuing in common use into the '20s. It was the product of a design evolution tracing back to the Curtiss V-twin motorcyle and dirigible engines of the decade prior to WW1.

The Hispano-Suiza was more or less contemporary in usage but, as a somewhat later design, was more "modern" and more powerful, benefiting from the rapid technology development of the war years. The early U.S. Airmail flew Jennies, but specified that they be powered by Hisso engines.

[RReid]

Hello all. I have added Achim's (fumopuc) valve timing data for his recently completed Snow engine to the Model Engines category.
Thank you, Achim!

https://www.modelenginemaker.com/index.php?topic=10726.msg247120#msg247120