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Discussion Starter #1
Since I just bought a nicer condition head (P79) for my 83 n/a, I was thinking about beefing it up a bit by shaving .080" and shimming the cam towers and valves springs (about 10:1 CR , right???). But then I was searching the archives and found a post by Wangsman that said I will get detonation problems if I run that high of CR and that little of a cam (stock). So if I went to a bigger cam, I should be OK, right? Even if it is one of those MSA stage 1 with 260/260 (I/E) or would bigger than that be a better choice? And just to ask, how much am I looking to gain by this expensive endevour? I was thinking only like 10 or 15 RWHP. Or more??

Thanks
 

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Just for comparison here is my setup:

F-54 w/Flat Tops
N-42 Shaved .013 (that I know of)
1mm Nissan MotorSports Head Gasket
Schneider cam .424/.430 lift ~226/230 Duration @ .050
93 Octane pump gas @ 40 PSI

NO PING.....at all

Note that is with the older style combustion chamber that is suppose to be prone to detonation. The P79 has the high swirl design that is suppose to be more resistant to detonation.
 

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I'm running that head setup with a 276/.480 cam and no detonation problems with premium fuel. It is "close" to detonation at 36 deg total so I'd think with a stock cam you might have some problems. Unless you're going to do some fairly major EFI mods, I wouldn't go past the MSA "stage 2" cam and the 260-260 should work OK. I wish they sold schneiders 260-270 cam but they don't. I asked if they could get this cam twice and never got a meaningful responce?
 

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If you want something from Schneider, call them direct.

<http://www.schneidercams.com/>

Telephone: (619) 297-0227
Fax: (619) 297-0577
E-mail: [email protected]
Street Address: 1235 Cushman Ave. San Diego, CA. 92110


They ground my cam custom, for $15 extra. They were very willing to help.

Here is their line up for the Z motor:

<http://www.schneidercams.com/cams/50.htm>



Post Edited (Oct 19, 4:33am)
 

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Discussion Starter #5
I've heard alot of good things about Schneider Cams in the last two days, but how come they are more expensive than MSA's when Schneider is the one who supplies them? It is the whole "buy in bulk" deal or does Schneider do discounts?
 

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Since you are in California, drive on down to San Diego and speak to them direct. In my book, I'd rather speak directly to the guy that grinds the cam, than talk to some rep that is only repeating what he has been told. That in itself is worth any extra coin it may cost.

Schneider was extremely helpful when I was dealing with them.
 

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Your CR will be 9.6:1. Stock cam should be fine w/ premium pump fuel. You shouldn't be choosing the cam based on the CR, though, you should be choosing your CR based on the cam you want for the desired powerband.
 

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Discussion Starter #8
Thanks everyone! To those who posted, or anyone else, have any of you had problems with vacuum for the timing after you set up a bigger cam? Also, how do you determine overall timing on these cars?
 

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well my buddy has only 5 hg at idle, you need to look up sweething2_5 posts to find out what size cam he is running, its huge. His brakes work fine though. Its a 77. I havent checked my vac yet but will soon. Vac should be around 15hg at idle.

Overal timing should be done with timing light with advance. My car is set up that the cam plate notch and V is right in the middle at 10 degrees btdc. So you could set your engine for that and it runs very well.
 

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You actually need to "power time" the engine which is setiing it at a high enough RPM so that all the mechanical advance is in with the vacuum advance unpluged. 35 deg is a good starting point.
 
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