Solid Roller camshaft selection those of you running a 408 race application - lobe seperation

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rslscobra

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Looking to install a new camshaft in my 408. Trickflow heads cnc ported, molnar crank/rods/icon pistons 12.25 to 1. Current cam 287/301 660/660 lift with a 108 lobe seperation at .050 254/268 and .440/.440
3350lbs Duster with 430gear and 29” tall tire.

Curious what everyone is running and which lobe seperation they find or found works best.

Thank you
 
By the math, it works out to be a 105.02 LSA.
This will produce maximum low end torque and earliest high rpm hp.
 
rslscobra said:
Looking to install a new camshaft in my 408. Trickflow heads cnc ported, molnar crank/rods/icon pistons 12.25 to 1. Current cam 287/301 660/660 lift with a 108 lobe seperation at .050 254/268 and .440/.440
3350lbs Duster with 430gear and 29” tall tire.

Curious what everyone is running and which lobe seperation they find or found works best.

Thank you
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What did it make for power? Carb? headers? fuel?
 
Just curious, what is your shift and trap RPM? Do you have a camshaft selected that you're going to have the LSA set on?
 
Garrett Ellison said:
Just curious, what is your shift and trap RPM? Do you have a camshaft selected that you're going to have the LSA set on?
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I do not have a cam shaft selected. Still researching that. Curious what others have found to work. Current cam shift at 6800 and traps around 7000

I’ve been told with a stroker 408 you want a 110 LSA but others say 104/106. This is why I am curious what others have found to work with a similar combo.
 
rslscobra said:
I do not have a cam shaft selected. Still researching that. Curious what others have found to work. Current cam shift at 6800 and traps around 7000

I’ve been told with a stroker 408 you want a 110 LSA but others say 104/106. This is why I am curious what others have found to work with a similar combo.
Click to expand...
Well, it’s a mathematical equation based on dyno tests.
There is a relationship between the CID & valve size diameter.
A 408 w/a 2.02 valve works best with a 105.02 LSA form max low end torque and best overall HP throughout the curve.

I have also noticed that the power peaks earlier (and more often than not, still better/higher) vs a wider LSA.
This would could be better since you’ll change gears earlier all else being equal.
 
rumblefish360 said:
Well, it’s a mathematical equation based on dyno tests.
There is a relationship between the CID & valve size diameter.
A 408 w/a 2.02 valve works best with a 105.02 LSA form max low end torque and best overall HP throughout the curve.

I have also noticed that the power peaks earlier (and more often than not, still better/higher) vs a wider LSA.
This would could be better since you’ll change gears earlier all else being equal.
Click to expand...
Sorry forgot to add the heads have a 2.08 exhaust cable
 
rslscobra said:
I do not have a cam shaft selected. Still researching that. Curious what others have found to work. Current cam shift at 6800 and traps around 7000

I’ve been told with a stroker 408 you want a 110 LSA but others say 104/106. This is why I am curious what others have found to work with a similar combo.
Click to expand...
With a 5400 rpm stall and 6800/7000 rpm shift and traps don't think you have to worry about bottom end too much :)

What/where is lacking (powerband) with the cam you're running now ?
 
I can see needing more camshaft if the goal is for the engine to rpm higher. Did you have the heads flowed after installing the 2.08 intake valves and how much lift will your valve springs support?
 
Garrett Ellison said:
I can see needing more camshaft if the goal is for the engine to rpm higher. Did you have the heads flowed after installing the 2.08 intake valves and how much lift will your valve springs support?
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Yes heads were flowed and springs good to 700 lift per Trickflow. I am having the heads reworked and will check spring pressure.

Attachment.jpeg
 
Nice work! I’ve been curious what a set of TFS heads could do with larger valves and corresponding seat and throat cuts.
 
PRH said:
You’re having the heads from that flow sheet reworked more?
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No, sorry did a leak down test and 4 of the exhaust valves leaked causing lower pressure in the cylinder. So, going to fix the heads, pick out a new cam, verify spring pressure and replace valve springs if needed. Card off to paint, so looking to continue what Bill started! Going to get a different converter too.
 
I’ve had a couple of conversations with Billet Cams and they seem to be verify knowledgeable. They recommended a camshaft that I think will make a difference.
 
rslscobra said:
I’ve had a couple of conversations with Bullet Cams and they seem to be verify knowledgeable. They recommended a camshaft that I think will make a difference.
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You're right on target talking to Bullet on cam selection. I was considering suggesting the old lunati pro comp drag race that they still have the master profile for, but I think they can recommend better than that if you're staying with 4.30 gears and 29 inch tires. I'm thinking that will require a little more lobe intensity than the pro comp grind, but I think the duration and overlap will be pretty close.
 
What do you want to gain from a camshaft change? More rpm? More power? More torque? Lower powerband? Those are the questions that need answers. There is no one size fits all camshaft that will be the “best” at everything.
 
TT5.9mag said:
What do you want to gain from a camshaft change? More rpm? More power? More torque? Lower powerband? Those are the questions that need answers. There is no one size fits all camshaft that will be the “best” at everything.
Click to expand...
More torque, more power. You are correct that’s why I went with Billet Specialty, so I can move on. Every cam company has their opinion, but Billet has a great reputation.
 
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