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Roller cam suggestion

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Cliff Ruggles:
For the 455's, cam selection once again is base on the static compression ratio, use of the vehicle, gearing, converter stall, etc.

I like cams around 230 @ .050" on a wide LSA for 9.5 to about 10 to 1 compression.  We have a custom hydraulic roller grind that we use here that specs out at 230/242/112, with .361" lobes.  We've used it with several sets of KRE aluminum heads in 455 builds around 10 to 10.4 to 1 compression with excellent results.

Another very good choice is the "Old Faithful" grind from SD Performance, specs out at 236/245/112.  It like a tad more compression and a bit more stall speed, but still a very mild cam in a 455 build.  I use this cam in my own 455 that pushes my Ventura nearly into the 10's in full street trim....Cliff

I'll be using iron heads, so I think I'll be shooting for 9.0-9.5 on the CR.  Is that too low for either of those cams? 

Cliff Ruggles:
Running more compression allows for more camshaft, all else being equal.  The compression ratio (effective) is determined as much by the cam as anything else.

The problem I've seen in recent years when it comes to this topic, is that folks believe there is a perverbial "brick wall" at 9.5 to 1 SCR with these engines.

My old 455 managed 10 to 1 for years on 87-89 octane pump gas with iron heads.  That same engine wen on to run a few more years with aluminum heads at 10.5 to 1. When pulled down for inspection, the bearings and pistons were in perfect shape.

My new engine is 11 to 1 on a steady diet of 89 octane fuel, and pushes my car nearly into the 10's in full street trim.  It would be a "turd" at 9 to 9.5 to 1 compression with the cam I'm using......Cliff

I know that you've succesfully managed higher compression ratios than most.  I also know that it doesn't happen by accident.  If I recall correctly, there is a list of 20 or so things that you do (that many people don't do) that enables you to move up the compression ladder.   I certainly plan to zero deck, but beyond that, what types of "mods" make sense for a nice torquey street motor?  CVMS will probably build the motor, so Jim's philosophy will come into play at some point, but I really like your approach to Pontiac builds am curious to hear what cam you would use given the relatively modest goals.   

That will be an interesting decision regarding the cam.  Especially if you are building a higher compression motor.

I too would like to hear Cliffs key factors in building a 10.0 -1 engine that runs well on 89 octane.

Cliffs build is proven to work. Whats the recipe buddy?
I know on my build I did at least 2 or 3 things he has described.


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