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Which Cams ?

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Old Apr 20, 2006 | 03:46 PM
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Default Which Cams ?

Hi,

I will be building my engine and upping the boost on my ATI SC to 14psi.

I currently have JWT spec. cams (260 duration 10.9mm lift) but with the new heads I'm getting (valves 1mm over) I'm also receiving Tomei 268 Cams (268 duration, 10.5 lift)

Question, which cams will work better in my car/setup and why?

Danny
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Old Apr 20, 2006 | 09:13 PM
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Anyone ? Lift vs Duration advantages/disadvantages ?

Danny
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Old Apr 20, 2006 | 10:32 PM
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Rule of thumb: "Ten extra degrees of cam duration will raise the peak power point by 500 rpm."

So I would be making peak power like 400 rpms higher than I am now. Since my SC makes max power just before redline, I would need to shift at 7K with the Tomeis to take advantage of all power...

Danny
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Old Apr 21, 2006 | 07:59 AM
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off topic, but please let me know if you decide to sell your JWT cams
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Old Apr 21, 2006 | 12:01 PM
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Originally Posted by William@Altered
I wonder why you want the extra duration - your car is not reving very high - if it was and you were taking advatage of say9k rpms - then yes - but your shifting at or below 7k -
With the UTEC, I would raise the REV limiter. Since I'm getting a build motor, heads job + valves & springs abd a VB & TC upgrade, I should be able to run higher revs safely.

It's not that I really want the extra duration, the set of heads & vales I bough come with those cams. I now need to decide if I want to stay with my JWT spec cams or go with the Tomei 268s. That is actually the original question...

Thanks

Danny
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Old Apr 21, 2006 | 12:05 PM
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Originally Posted by mdacko
off topic, but please let me know if you decide to sell your JWT cams
Just the JWTs or also if I decide the Tomeis have to go ?
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Old Apr 21, 2006 | 02:20 PM
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I'd choose Tomei anyday over JWT.
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Old Apr 21, 2006 | 02:21 PM
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Looks like it will be the Tomeis and the JWT specs will have to go ...
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Old Apr 22, 2006 | 11:22 AM
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:P stock cams
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Old Apr 22, 2006 | 05:46 PM
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Scott's cams. 242 duration, 10.5mm of lift, minimal overlap. perfect for forced induction.
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Old Apr 23, 2006 | 12:34 PM
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Are you sure their duration is only 242?
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Old Apr 23, 2006 | 03:06 PM
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Originally Posted by Bullitproof
Scott's cams. 242 duration, 10.5mm of lift, minimal overlap. perfect for forced induction.
Where did you get this info?
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Old Apr 23, 2006 | 03:59 PM
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Originally Posted by G352NV
Where did you get this info?
He has the same cams as I had...which are different than yours Steve....I think your duration is different right??
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Old Apr 23, 2006 | 04:41 PM
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Originally Posted by Sharif@Forged
Are you sure their duration is only 242?
Tomei cams come in:

Tomei Cam 256 /EX: 10.2 / IN: 10.2
Tomei Cam 264 /EX: 10.2 / IN: 10.2
Tomei Cam 268 /EX: 10.5 / IN: 10.5

JWT spec'ed ones are:

260 DEG DUR. / .428"(10.9MM) LIFT, INT. ADVANCED 2 DEGREES.

Nismo:

262 degree duration and .426" (10.8mm) lift. Cold lash is set at .010" to .013".
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Old Apr 23, 2006 | 04:57 PM
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Originally Posted by bigbri
He has the same cams as I had...which are different than yours Steve....I think your duration is different right??
Naw I was told mines are the same as yours. Scott only makes one FI cam.
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Old Apr 23, 2006 | 07:04 PM
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Everything I read about cams says "keep overlap as small as possible for FI". Does anyone happen to know how much overlap the JWT and/or the Tomei have ?

Thanks

Danny
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Old Apr 23, 2006 | 07:24 PM
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Originally Posted by G352NV
Naw I was told mines are the same as yours. Scott only makes one FI cam.
Scott makes more than 1 FI cam bro...there are 3....
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Old Apr 23, 2006 | 07:52 PM
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i got that number from the box.... and i i'm fairly sure my installer got that number from Ted also. these are true f/i cams. the other ones are n/a cams that work well with f/i cars. scotts performance kept the duration down, the overlap to a minimum.....here's your choice. i'm not sure if you have to shim the jwt's but i'm pretty sure you have to with the tomei 268's. scott's cams a hollow too!!! i'll let you guys know what kind of numbers i get with these cams after tuning.
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