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Discussion Starter #1
I'm not having any luck with the search engine on this.
I just bought a comp cams 268h for my 67 390GT, Not looking to race the car just want a little more low end torque and better sounding idle. Also the car has a c6 auto with power brakes, cruise control, headlight doors etc. etc. all vacuum.

Ok, my question is, in the description with the cam and lifters set it says that new valve springs are required, Is this true with the GT/428SCJ heads or are they just talking about the FE engine in general?
Just for the info, the heads were just rebuilt with new factory correct GT springs installed.
 

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Comp will recommend parts (cam, springs, retainers etc....) that work well together. Check to see what springs they suggest (looks like #940-16) and compare them to the stock GT/CJ springs. I think your cam would be ok with the stock springs you have but it's best to double check all the parts vs specs to be sure they do indeed match the suggested specs. Are they NOS springs or?? Also note comp uses the 1.73 rocker ratio spec for rockers. If your using the stock non adjustable those are fine but if using a 1.76 adjustable it'll add .03 lift to your specs.
 

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I'm trusting the local speed shop that I had rebuild the heads on the factory spec springs, I am using the original non adjustable roller rockers.
My current plan is to install the cam and then crank the engine by hand and measure the valve springs.
 
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