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Title: Web 251 camshaft advance? Post by: neil68 on June 24, 2015, 19:06:42 pm I'm going to install a Web 251 camshaft that I've had for a few years. Will also bump up the CR to 11:1.
Should I install the cam straight up, or advance it 2 degrees, 4 degrees, etc? I want to try it out primarily for the drag strip. Anyone have experience with this cam? The specs are similar to an FK89, as far as I can tell. Thanks! Title: Re: Web 251 camshaft advance? Post by: LGK on June 25, 2015, 07:10:42 am I'm going to install a Web 251 camshaft that I've had for a few years. Will also bump up the CR to 11:1. Should I install the cam straight up, or advance it 2 degrees, 4 degrees, etc? I want to try it out primarily for the drag strip. Anyone have experience with this cam? The specs are similar to an FK89, as far as I can tell. Thanks! Title: Re: Web 251 camshaft advance? Post by: neil68 on June 25, 2015, 19:41:59 pm My current Raptor 06908 camshaft has more lift (10.8 mm/0.425") than the Web 251 (10.7 mm/0.420").
However the Raptor has a shorter duration (274 degrees @ 1.27 mm/0.050"). So I was looking at the advantage of having the intake valve open a bit longer with the Web 251 (285 degrees). As it turns out, I had forgotten that my Web 251 was incorrectly ground...I think they used the smaller Type 4 spec in error. I might try another Raptor with more duration, but CSP seems to be out stock at the moment. Title: Re: Web 251 camshaft advance? Post by: Erlend / bug66 on June 26, 2015, 08:06:19 am My current Raptor 06908 camshaft has more lift (10.8 mm/0.425") than the Web 251 (10.7 mm/0.420"). However the Raptor has a shorter duration (274 degrees @ 1.27 mm/0.050"). So I was looking at the advantage of having the intake valve open a bit longer with the Web 251 (285 degrees). As it turns out, I had forgotten that my Web 251 was incorrectly ground...I think they used the smaller Type 4 spec in error. I might try another Raptor with more duration, but CSP seems to be out stock at the moment. Buy one directly from Johannes? Title: Re: Web 251 camshaft advance? Post by: neil68 on June 26, 2015, 20:41:49 pm Yes, I will, however the JPM website has been off line for a few days, and CSP only lists advertised duration, so I'll have to get additional information on what cams are available from Johannes.
Title: Re: Web 251 camshaft advance? Post by: Erlend / bug66 on June 26, 2015, 22:51:15 pm Yes, I will, however the JPM website has been off line for a few days, and CSP only lists advertised duration, so I'll have to get additional information on what cams are available from Johannes. Works fine for me; http://www.jpmotorsports.se He'll do any custom cam also. Title: Re: Web 251 camshaft advance? Post by: Kiel on June 27, 2015, 15:49:08 pm I have the 251 i my 2,4 liter type 4 engine. 103mm x 71mm
comp is 11,5 and use jpm valve spring, run it to 8000 rpm. no problem with 48mm and 40mm type 4 valve. The cam are set to o degress. http://youtu.be/T0IsZAJPlgg Title: Re: Web 251 camshaft advance? Post by: Torben Alstrup on July 04, 2015, 12:50:23 pm If you decide on a 251 , and the engine is for drag mainly, I would set it up in zero (108 lc) It does not need more spring pressure than an FK89 due to a better opening and closing ramp. Power wise I couldnt say which is the better 251 versus FK89. But the 251 seems to have a cleaner idle and pulls a tad earlier. At least that is what I have noticed.
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