Exhaust Ports

[Zero_12]

hey everyone,

I am working on setting up an engine model using GT-Power. I am away from campus for the summer, so I don't have access to the tools to find all the dimensions for the exhaust ports.

Our engine is a F4i.

I have the diameter for the ports from the valves at 22 mm and the port to the exhaust at 30.5 mm. Would anyone be willing to share the lengths for each of these sections?

One last thing:

I have seen people talking about the Cam Plus Pro tool to measure lift vs. angle for the cams. Is this something a local bike shop might have, or is this tool more for racing shops?

Thanks

[Zero_12]

hey everyone,

I am working on setting up an engine model using GT-Power. I am away from campus for the summer, so I don't have access to the tools to find all the dimensions for the exhaust ports.

Our engine is a F4i.

I have the diameter for the ports from the valves at 22 mm and the port to the exhaust at 30.5 mm. Would anyone be willing to share the lengths for each of these sections?

One last thing:

I have seen people talking about the Cam Plus Pro tool to measure lift vs. angle for the cams. Is this something a local bike shop might have, or is this tool more for racing shops?

Thanks

[Wesley]

Or you could just get a degree wheel and a dial indicator.

[Zero_12]

Wesley,

Have you had any success using a degree wheel and dial indicator? From reading some of other posts, it seemed like people were getting inaccurate results using other methods besides the Cam Plus Pro tool.

[Krautsalat]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Have you had any success using a degree wheel and dial indicator? From reading some of other posts, it seemed like people were getting inaccurate results using other methods besides the Cam Plus Pro tool. </div></BLOCKQUOTE>

What do you intend to do with the data? Only for a 1D simulation or valve train dynamics? For GT-Power this will be accurate enough, done it several times.

Krautsalat

[Zero_12]

For now, just planning 1D simulation, but if time allows, then we may consider doing some cam modifications.

[Wesley]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Zero_12:
Wesley,

Have you had any success using a degree wheel and dial indicator? From reading some of other posts, it seemed like people were getting inaccurate results using other methods besides the Cam Plus Pro tool. </div></BLOCKQUOTE>

Well you can't just drop the indicator probe on the cam, you'll have to duplicate the cam follower in a bucket so you get the real values, as the contact location of the cam/follower varies as it rotates.

[BeaverGuy]

An easy way to measure the valvelift profile is to remove the head from the engine, change out the valve springs for something lighter. Now mount a degree and dial indicator to measure the movement of the valve. I had no problems getting acurate measurements doing this as long as I kept the dial indicator travel parallel to the valve travel.

[fart can]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BeaverGuy:
An easy way to measure the valvelift profile is to remove the head from the engine. </div></BLOCKQUOTE>

Head gaskets cost about $80, wouldn't it just be cheaper to have a shop like WebCams profile the cam?