Which cam will have more radical idle?

[Rat Patrol]

Lunati Hyd Roller - 20200713 - .560"/.565" - 243/251, 294/302, 110/106

or

Comp Solid flat tappet - - 520/540 - 244/252 282/290 110/106

 

[1968FormulaS340]

My guess would be the Lunati but you better have a combo going that will support either one.

Those are not cams for a stockish engine.

 

[64physhy]

The first one probably, but either of those cams would need the gears, torque converter, heads, headers, carb, and intake for them to do any good. Probably about 4.10 gears, 32-3500 converter, a 750 or 850 cfm carb, and some decent heads with 2.02 intake valves

 

[MRL Performance]

To determine the power range of a cam you look at duration at .050". These 2 cams are just about identical.

To determine the idle quality you look at duration at advertised. The Lunati cam will have a much more noticeable idle to it. A little choppy.

 

[Rat Patrol]

Thanks - Its a 318/392 with an 800 AVS, M1, 3800 stall and 3.91 gears.

I guess I could assume the Lunati will make more unde the curve?

 

[70dart340]

The flat tappet cam will have a nastier idle than the roller. Rollers have a quicker opening and closing ramp, that's their advantage. Both will require a stiff set of springs.

 

[1970Duster]

The flat tappet cam will have a nastier idle than the roller. Rollers have a quicker opening and closing ramp, that's their advantage. Both will require a stiff set of springs.

Yes and no. Roller cams bring you into the power curve sooner and keep you there longer vs flat tappet cam. So yes, roller cam open sooner but stay open long then flat tappet cams. That said I'd go roller very time, which is why I have a full roller setup in my 340.

 

[Rat Patrol]

So Lunati 3 - Comp 1.

I guess they are fairly close - I wondered if the lift of the LUnati would effect the idle?

 

[1970Duster]

If you go with a roller cam, just make sure it has a cast iron gear on it. Otherwise you have to run/use a bronze gear with it and have to constantly rip the motor out of the car and rebuild it. I know crane has the intergrated cast iron gear on it so you can just use a hardened intermidiate shaft.

 

[mullinax95]

There is a huge price difference in the cams. Go roller no doubt.