ZL1modified

well, can you... thats what i am running now because i can't afford springs yet...
is this going to damage my valvetrain or hurt my performance?

i have comp pro mag NSA 3/8" stud roller rockers and 47000 miles on the engine...



thanks

2000GTP

I wouldn't. I would use LT4 springs at least. You can get a set for 40 or 50 bucks, not very expensive at all.

ZL1modified

would that still be enough to consider it a stock motor...
tring to leave it stock... heard that rr's keep you stock...

2000GTP

I would consider a roller rocker upgrade a deviation from the stock setup.

ZL1modified

so would headers and EWP then... i read somewhere that they were just a bolt on upgrade and that anything lower on the valve train would take you away from stock...

who knows the rules though...

OBE1 95Z28

You're mixing 2 issues, first you ask if it will hurt your engine, then you want to know if it will still be stock. As far as hurt your engine, you run the risk of coil bind that can hurt your engine. My friend broke 2 push rods after 10K miles of running 1.6 RR's without changing the springs. I understand that a lot of guys don't have issues so it's up to you, do you feel lucky? As far as still be considered as stock, it would depend on the rules of the class you're trying to compete in.

shoebox

There aren't any rules.

...but 1.6 rockers are not stock. IMHO, stock is pure stock. With anything changed, it is no longer stock.

Dave89IROC

I say anything inside/below the valve covers is more then bolt-on

EWP, Headers, ect. would all be bolt-ons

wdtiger

I guess the real question would be, "stock according to what rules?" If you've got all the mods listed in your sig, i'd say you're far from stock according to most racing bodies.

2000GTP

Exactly. So I don't see why it would matter if you were to run stiffer valve springs.

T/A-Bob

You can run the stock springs. With a completely stock set-up... Installed height = 1.78". Coil bind height = 1.26" This leaves 0.52" of total (theoretical) lift. The stock cam has 0.46" of lift at the valve. This leaves 0.06" of clearance for the spring (before coil bind). Most sources will tell you that 0.06 (or greater) is a "safe" amount of clearance.

When you go to 1.6 rocker arms, the lift increases to 0.49". This leaves 0.03" of clearance on the springs (before coil bind), which is less than the 0.06" that is the generally accepted minimum.

Can you get by with 0.03" of clearance? Maybe, probably, but there must be a reason why the 0.06" minimum is so widely considered the standard...

I'm running my engine with 1.6rr's and stock springs. I just turned 51K on the clock. I'm not recommending you do it, but I decided to.

The LT4 springs seem to be very good & very inexpensive for this type of application. If the work of changing out your springs is not an issue, then I would definitely change out the stock ones.

marshall93z

I had them on mine with stock springs for probably 30,000 miles and never hurt anything.

BUT, I am NOT saying you should do it!

Rob1997ta

I was told from a guy at crane cams that I would be fine with factory springs.

SnakeSkinner28

You should be fine to run 1:6 rockers. I have had them for well over 40K on stock springs. One thing I did was get hardend pushrods, they were cheap and easy just incase the stock ones were weakend over time. And unless your running professional class racing who cares if you call the motor stock or not. But like most people I would say once the valve covers are off its not stock anymore.

Rob1997ta

I got chrome molly pushrods also.