Cyclerama 575

[Baja555]

Does anyone have any thoughts or experience on trying 1.7 rockers on the intake side of the cr575 cams?

[Don D]

Maybe, intake only. No guarantees it will help hp or torque and the springs and other valve train have to be capable of going there.

[kd]

Does anyone have any thoughts or experience on trying 1.7 rockers on the intake side of the cr575 cams?

What style heads are you using?  Have you considered an up-sized intake valve instead?

[Baja555]

Standard 103 head castings street ported. No didn't think of bigger valve. Was kinda thinking maybe worth a try with rockers on intakes. Would be fairly easy

[kd]

Less stress on the valve train if you can accomplish what you need by valve size instead.  IMO  If you are getting max fill effect with the valve size then it's not too likely the rocker ratio change will be a significant gain.  Same air, less wear.

[Baja555]

Thank you

[jsachs1]

Other things to look at if you go with the 1.725 arms.
Push rod hole diameter in the head to push rod clearance, and push rod to push rod tube clearance. The extra length of the rocker arm is toward the push rod end.
John

[Baja555]

Ok thanks , may be more trouble than it's worth

[Ohio HD]

Drill the upper tubes to 5/8" about 1.5" deep from the top. That helps a lot with clearance.

[thirdgear]

How do you drill them and not crush them? In a lathe?

[Ohio HD]

Yes, chuck them up and use a stationary drill bit.

[thirdgear]

Thanks I can do that.

[Don D]

Or this

[jls 64]

Thanks I can do that.
[/quote
That is the way] p

[thirdgear]

That collet set up is sweet. I do have a three jaw chuck on my grand fathers old atlas lathe.

[spdrcr]

Standard 103 head castings street ported. No didn't think of bigger valve. Was kinda thinking maybe worth a try with rockers on intakes. Would be fairly easy

What are you getting out of your current set up?

[Baja555]

117 hp and 130 tq

[Tail Ridr]

This on a 110?

[Baja555]

113

[N456SK]

How much compression?

[Baja555]

10.5