cam selection help

[Hightower1]

Hi all,

I have been searching the interweb for ideas on my engine rebuild. Found this forum to have a lot of knowledgeable and helpful people.

My engine is a gen 6 454. I got the engine about 4 years ago and it is my first BBC so I am still in the learning phase. The engine was in an 80's truck when I bought it and I was told that it had been rebuilt somewhat recently. It ran great! I wanted to do a few upgrades and use the engine in my 4x4 for mud bog competitions. I didn't know it was a gen 6 or that there was different gens until after much frustration in matching parts. It has ran awesome the last 4 years but I am getting some low compression readings on a couple of cylinders so I am going to pull it and have it checked out. I also suspect due to my recent research that I am running the wrong intake on it. But my main concern is the cam. The cam I used works great but I think after researching that there may be some better options out there. Supposedly this motor should have came with a roller cam but it did not have one when I got it. I just assumed it was stock and replaced it with a Lunati flat tappet "10110703" 268/276 227/233@.050 .542/.554. Also converted it to adjustable rockers.

So while I have the engine out I am wondering if I could find a roller cam that will give me better performance. The heads are 10114156 which should be "peanut" port small valve heads. I don't plan on replacing them because they work great for my application. Lots of low to mid range torque. I am thinking my compression ratio is probably 9:1. My intake is an Eldebrock rpm performer but I suspect that it is made for large oval ports rather than the small ovals so I plan on replacing it with a performer for the small ports. I also have headers, MSD ignition and a Holley 750. I run it with the transfer case in low range giving me a final drive of 6:16 with 38" tires and a 2500 stall.

The class I race in requires full exhaust and the engine must pulll 15" of vacuum at 1000 rpm. I have to advance the timing at idle a lot to get the 15". As I said the engine runs like a beast so I have no problem leaving it as is other than the intake but am open to ideas for a roller cam that might give me better performance and better vacuum.

Thank you!!!

[techinspector1]

Replacing a Performer RPM with a Performer is taking a step backward, regardless of the port fit.

I don't think it will be possible to choose a catalog cam for the motor, you need to call one of the grinders and explain your vacuum rule to them, then have them cut a shaft for you. In my experience, Howards would be the least expensive and still have excellent quality for the money.
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[Hightower1]

Thanks for the reply! Since my original post I have found that my current rpm intake is the correct port size. I will give Howards a call and see what they say.