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Discussion Starter #1
I always thought a solid roller cam would make more power is this always true? I just had a new sbf 8.2 352 ci blower motor built running a ysi and 25 lbs boost and went to a larger solid roller cam and after porting the heads( old hiports) larger cam 670 lift ,it made less power.
I wanted to know where to start to find out what might be wrong?
motor is also down on boost a little but its not intercooled so I don't think this cold be the problem??
Thanks for any help
 

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`Larger cam not always better with a blower/turbo setup.. The cam must be custom to the combo/// off the shelf cams will work but will not preform as well as a custom grind... Solid cam = higher RPM with less problems... I would say the cam is your issue
 

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motor is down on boost - Found your problem

Larger heads, bigger cam that bleeds off boost, lots of variables in the combo.

If you lost 5lbs with the new cam/heads then you could be down 100-150hp or more in some cases.
 

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Discussion Starter #4
motor is down on boost - Found your problem

Larger heads, bigger cam that bleeds off boost, lots of variables in the combo.

If you lost 5lbs with the new cam/heads then you could be down 100-150hp or more in some cases.
I'm still using the same heads with a little porting ,could the cam not be degreed properly?
Thanks
 

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Discussion Starter #7
how much overlap? new vs. old
The new cam valve overlap is 45.4 crank deg.
lobe seperation= 112.2 cam degree
The old cam is one of those secret squirrel ones I got from Larocca years ago. I know its alot smaller. I will try to look it up...

Thanks for your help!
 

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I have one of Jimmy Larocca,s cams in my old combo and i know he liked 115 lobe center.Are you sure with the 112 you are not blowning the boost pasted the valves? 112 is more of a NOS cam i thought? Im no ex on this but just a thought.Are the valve springs good or maybe a little weak if used? Good luck.
 

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I'm sure the blower is putting out the same amount of air,so you can't really say loss of boost is the problem,as boost is just a measure of restriction/backpressure,and since you ported the heads,should maybe be less? I would say the cam is not as efficient.???
 

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Discussion Starter #11
I'm sure the blower is putting out the same amount of air,so you can't really say loss of boost is the problem,as boost is just a measure of restriction/backpressure,and since you ported the heads,should maybe be less? I would say the cam is not as efficient.???
I think its the cam also.
Thanks
 

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If its a Larocca cam, its pretty good. All of my stuff is still being done and designed by him. My good friend is his best friend. PM me if you want, I will put you intouch with my buddy. He is very very good on cams.
 

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Discussion Starter #13
If its a Larocca cam, its pretty good. All of my stuff is still being done and designed by him. My good friend is his best friend. PM me if you want, I will put you intouch with my buddy. He is very very good on cams.
OK Thanks
 
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