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View Full Version : Adv Camshaft Duration?



cheezoto(OU-FSAE)
02-25-2003, 06:03 PM
Wow i can beleive this has been so hard to find, but does anyone know what the Advertised Intake Camshaft duration is for a Honda CBR600F4i?

I found the duration numbers at

.020in lift = 268deg
and
.050in lift = 242deg

but what the heck is the total Adv duration from open to close.

Thanks guys

University of Oklahoma
FSAE Vice President
FSAE Engine Systems Leader

cheezoto(OU-FSAE)
02-25-2003, 06:03 PM
Wow i can beleive this has been so hard to find, but does anyone know what the Advertised Intake Camshaft duration is for a Honda CBR600F4i?

I found the duration numbers at

.020in lift = 268deg
and
.050in lift = 242deg

but what the heck is the total Adv duration from open to close.

Thanks guys

University of Oklahoma
FSAE Vice President
FSAE Engine Systems Leader

Kevin Hall
02-25-2003, 08:29 PM
We are currently in the process of having our F4 cams profiled, and possibly reground. When we get the data (Colt Cams is doing it), I'll be sure to post all the relevant data that I get. Till then, good luck!

Kevin

tommy
02-26-2003, 05:25 PM
here ya go

everything is at 1mm (0.04 in) lift

INTAKE
opens 22 deg BTDC
closes 43 deg ABDC

EXHAUST
opens 38 deg BBDC
closes 7 deg ATDC

thats straight from the service manual...ill leave the math for you im busy http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

Charlie
02-26-2003, 06:40 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by cheezoto(OU-FSAE):
Wow i can beleive this has been so hard to find, <HR></BLOCKQUOTE>

Like he said, service manual. No engine guy should be without one. http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

-Charlie Ping
Auburn University FSAE 1999-present

Alfonso Ochoa
02-26-2003, 11:06 PM
As cheezoto said, from open to close, not at 1mm. The manual is useless at all for this data, it just gives you data to calibrate your valves.

Does anybody has this exact data?

I've calculated it at 310?(not sure) for intake and 314? for exhaust. This came out from the lift curves against crankshaft degrees I got from Virtual Engine using the cam profiles they give me.

We haven't opened our engine so it would be cool to hear from someone that had done this.

Thanks,

Alfonso Ochoa Vega
cabezota311@hotmail.com
F-SAE USB Team, Venezuela

Charlie
02-26-2003, 11:14 PM
I guess, I didn't read his question closely enough, however he asked for advertised duration in the first line, and generally advertised is at 1mm or .050, not total.

-Charlie Ping
Auburn University FSAE 1999-present

tommy
02-27-2003, 10:20 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Alfonso Ochoa:
As cheezoto said, from open to close, not at 1mm.
<HR></BLOCKQUOTE>

As far as I know there is no way to compare duration numbers without a standardized open value (like 1mm), right?

what if you consider open to be 0.1mm, and another guy considers it to be 0.5mm, you both will get different duration values.

It's my understanding that cam events are measured at a standard lift to eliminate such errors, so everyone is on the same page.

I'm also not sure what the benefit of knowing complete duration (however you define it) is over duration at 1mm lift. If you are timing injector pulses I don't know if that extra 1mm of travel til close will make a signficant difference.

any opinions?

cheezoto(OU-FSAE)
03-01-2003, 03:14 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> I guess, I didn't read his question closely enough, however he asked for advertised duration in the first line, and generally advertised is at 1mm or .050, not total.
<HR></BLOCKQUOTE>

Ok thats what i needed to know, the formula i am using asks for Adv Duration. And if Adv duration is usually measured at .050" then i am set, because i have the duration values at .020 and .050"

Thanks guys, i can cut my runners to length now.

University of Oklahoma
FSAE Vice President
FSAE Engine Systems Leader

Adam Berman
03-07-2003, 08:26 AM
Our Stock 2001 Suzuki GSXR 600 has 244 degrees on the intake with .337 max lift and 224 degrees on the exhaust with .286 max lift. That being said we had our cams hard-welded and regrounded for more lift and duration to deal with the restrictor, even though we want to lower our torque peak. You are talking about advancing the cams meaning that your exhaust timings begin and end sooner and so does your intake.

Adam Berman
03-07-2003, 08:34 AM
either that or advertised duration...in that case its either at 1mm lift (0.040") or 0.050". Most cam shops can work with either value.