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Discussion Starter #1
I have a 1969 Chevelle with a 454 that I feel should be faster or at least has the potential to be faster. My specific question is in regards to the current camshaft/rocker ratio. I'm running a Comp 288A-R10 solid roller with Crower 1.6 roller rockers. Specs for the cam are 246/246 @ .050 with .3666/.3666 lift and a 110LSA. With my 1.6 rockers that's only a .586 lift.

The engine is a 4.250 bore/4.000 cast crank, 12:1, Edelbrock 6055 heads with mild cleanup on exhaust by me (picked up .20 and 1 MPH), Comp valve spring 929-16 as recommended with the cam, Victor Jr and an 850 Holley.

The car weighs 3530lbs with me in it, has TCI TH400 w/brake, B&M 3000 Holeshot, 3.73 and 28x10.5 MT slicks. Best run is below and was at Fontana Dragstrip in CA.


60ft - 1.545
1/8 - 6.979 @ 98.850
1/4 - 10.993 @ 121.630


So given the rest of this combo would I benefit from upping the rocker ratio to a 1.7 or 1.8 or from a different cam with more lift and duration? What are your thoughts?
 

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Sounds like a pretty fair combo for a street/strip car with that small a cam, but I think a bigger cam will pick it up some. My pick would be a custom roller from Bullet Cams
 

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I have a 1969 Chevelle with a 454 that I feel should be faster or at least has the potential to be faster. My specific question is in regards to the current camshaft/rocker ratio. I'm running a Comp 288A-R10 solid roller with Crower 1.6 roller rockers. Specs for the cam are 246/246 @ .050 with .3666/.3666 lift and a 110LSA. With my 1.6 rockers that's only a .586 lift.

The engine is a 4.250 bore/4.000 cast crank, 12:1, Edelbrock 6055 heads with mild cleanup on exhaust by me (picked up .20 and 1 MPH), Comp valve spring 929-16 as recommended with the cam, Victor Jr and an 850 Holley.

The car weighs 3530lbs with me in it, has TCI TH400 w/brake, B&M 3000 Holeshot, 3.73 and 28x10.5 MT slicks. Best run is below and was at Fontana Dragstrip in CA.


60ft - 1.545
1/8 - 6.979 @ 98.850
1/4 - 10.993 @ 121.630


So given the rest of this combo would I benefit from upping the rocker ratio to a 1.7 or 1.8 or from a different cam with more lift and duration? What are your thoughts?
Looks like it runs pretty good for the combo and weight...What is your compression ratio and what type of fuel are you willing to run?

I'm sure there is a better torque converter out there also.
 

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Discussion Starter #5
It has 12:1 compression and I run it on VP110. I do have a new Freakshow converter as well but I'm still putting the trans together so I haven't run it yet. Given the rectangular port heads that are supposed to flow well up to .700 lift do you guys think switching from the 1.6 rockers to a 1.7 or 1.8 would be worth anything?
 

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I would go in this order:


  1. pick a target RPM to cross the finish line at
  2. do your heads, intake, carb and bottom end support that RPM?
  3. pick a cam and springs that support the target RPM
  4. pick a tire size
  5. pick a gear size
  6. pick a converter that will be between 1200-1500 RPM below your shift point
  7. Run the crap out of it!


Good luck,
Cole
 
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