cam choice

[justramit]

Last season we could only run cams that would pull 15 in vaccum at 1000 rpm. This year we can either pull 15 in vaccum or run any can as long as lift isn't over 480. I have been running cam that is 244/244 and .510 lift on 112 to pull vaccum. Would I be better of with cam that is 248/248 and .475 lift on 106? Which is better more duration or lift. Running 4412 carb and max rpm about 7000 rpm

[perfconn]

Depends on how good your heads are but duration @ .050 on intake is more important than lift.

[justramit]

They are out of the box eq 72 cc heads with 180cc runners. We can't port or polish, run 2701 intake 4412 carb and can only run 1.5 ratio rockers. Compression 10:1

[perfconn]

I would try a 244-250-106 lobe seperation.Degree the intake lobe in at 102* and order a pretty aggressive lobe with the 1.50 rockers

[justramit]

This is lunati cam I was thinking about trying
In. Dur @.050" Ex. Dur @.050" In. Lift/Ex. Lift Lobe Sep. Adv. In. Dur. Adv. Ex. Dur. Valve Lash

248 248 .475"/.475" 106 274 274 .014/.014


This Is bullet cam I have been running


In. Dur @.050" Ex. Dur @.050" In. Lift/Ex. Lift Lobe Sep. Adv. In. Dur. Adv. Ex. Dur. Valve Lash

244 244 .518"/.518" 112 274 274 .024/.024

[let-r-eat]

I probably wouldn't chose either of those but out of those 2 cam1 but neither is going to make much of a noticeable difference IMO> I don't like the 112 LSA and prefer the 106 but .020 or .030 thou lift is about the same difference as dropping 1/2 pound on the chassis.

[justramit]

What would you suggest? how about 242/242 with .500 lift on a 109. This is what cam grinder suggested.

[dontpanic]

That cam is close to what you are currently running, I couldnt imaine a noticable differance between the 2 on the track

Cheers

[justramit]

Major intensity on one I have now is 30 his would be 24. Dunno how much difference aggressive ramps would make

[perfconn]

You don't want a 109 lobe seperation on dirt.Aggressive lobes will make much more power.Order the cam you need they aren't more expensive than something that won't work.

[justramit]

Cam craft is suggesting cam that is 242/242. .500 lift on. 111 lobe. Major intensity 24

Lunati cam is 248/248. .475 lift. 106 lobe. Major intensity 26


I am not worried about cost I just want to run what will run best in 10:1 355 180cc eq heads. 4412 carb. Max rpm 7000 maybe a lil more. 1/4 - 5/16 track. We either have to pull 15 vaccum @ 1000 rpm. Or we don't have to worry about vacuum if we run 480 lift or less. The first can is about best can do and still meet vacuum rule. The cam all front runners are running now is 244/244. 518 lift on 112. Major intensity 30.

[sj valley dave]

I'd call Mike Jones at Jones Cams. He is really good to work with...704-489-2449

[stockcar5]

go with the camcraft cam. his stuff makes great power with very flat torque curves.

[DANNY]

Two things:

1- What rocker ratios can you run?

2- Correct me if I am wrong, Im not a cam guy. I barely know enough to get by and then its not enough. BUT wouldnt it be best to go with a custom ground cam with a 106 LS and make it say for 1.7/1.6 ratio rockers to get that .480 lift at the valve that you can run for the motor and rpm range?

[justramit]

Can only run 1.5 ratio

[DANNY]

Bummer I missed that above sorry... I still believe a custom grind is the way though lift is not end all be all in a cam, the profile is the key though.

The cam I have (though rules are open to whatever as long as no roller) varies from a buddy of mine in such a way as he describes his motor as "SNAPPY" they may make close power in the end however how they get there is way diff mine is smooth and never really gets that quantum like "jump surge" that can cause driveability issues... Instead it just PULLS!!!

I know Im not really helping much rather then just giving an opinion but a cam company is where I would start...