Yesterday was my first real day driving with the 1.6 mags on. It is idling at like 650rpm and has a little to surge to it? is this normal? I have a PCM4LESS tune in it right now--not tuned for 1.6's. Should I get it tuned or is it pretty much not neccessary. I still think that I have a problem up top though--this couldn't be because of tuning could it?

If i don't get it figured out soon I'm doing to the dyno.

 

make sure you didnt over tighten them ...... you dont really need to mess with the tune after roller rockers

 

I set them with 1/4 past 0 lash.

 

Sounds tight though if the idle is down. How did you find 0 lash?

 

can you spin the pushrod with your finger tips when the rocker is on?

 

I used method IOEC method on shoebox's site it's method 3. I went till i coldn't spin the pushrod with a light tough of my fingers then 1/4 more? I have a pop noise up top too, which was starting me lean twards it's too tight.


I got to thinking later though, would just cranking the pully over by hand that small amount pump up the lifters good enough??

 

When? After it has just ran or after the lifters bleed down?
I am starting to think that I might just redo them.

I have a very loud pop on the left bank somewhere @ near 5600 rpms. Could this also be indicating that they are too tight? and maybe the exhaust valve isn't quite shut all the way.

 

part throttle is bad, more like a stumbling/vibration also---I have a miss for sure, but too tight of rockers could cause a bad part throttle acceleration?

I think you guys might be right, it must be too tight. If no one else has ever seen a decrease in rpm at idle with these i would say it's too tight.


I am usine autolite 103's in it right now. 2 stages colder than stock for nitrous. I wounder if these plugs are causing some of the problem too.

 

Set them running. Easiest way to me, I could never get it even close with the car off.

 

Are you using the stock springs? If so, your probably experiencing coil bind. The stock springs are kinda iffy with 1.6 rockers.

Re'

 

I didn't see any of the issues you mention when I switched to 1.6RR's. I also swapped out to LT4 springs. Drove as smooth as ever. The exhaust note changed ever so slightly to a thumpier sound, but barely noticable.

Dan

 

Dan,
What RR's are you running?
Do they have poly-locks?
Are youe torqued to 1/2 turn past zero lash?

Thanks

 

I have Non Self Aligning 1.6 RR Pro Mags
7/16" studs
GM Guideplate
LT4 Springs
Hardened Pushrods.

Lash was set to 3/8 turn, but if you use the stock 3/8 studs, you should lash them to 1/2 turn. I don't set lash by trying to spin the pushrod. I just tighten the rocker until any free up/down movement is removed from the pushrod. That is zero lash, and it's pretty obvious where zero lash is. It's that points where you just barely take up all the slack in the pushrod.

Dan

 

I am using brand new LT4 springs, hand checked each one and the exact same set-up as steroman has mentioned. I will re-adjust them soon and see what happens.

 

Has anyone ever had the idle go down after 1.6RR install from the increased lift? If not, I am going to loosen these up some.