undercoverz-28

i'm going to a crane cam roller rocker gold series 1.6 ratio and was just wondering what kind of hp/torque increase i should see. thanks.

Ed Wright

iTrader: (1)

Are you are putting them on a stock engine? I put a set on mine when it was stock, baselined the car with four pulls on the dyno, swapped them out while still sitting on the rollers, tested it again, at the same intake air and coolant temps, found 3.5 rwhp averaging four pulls each way. That was about $100.00 per rwhp.

If your engine is stock, and you have not bought the rockers yet, I would spend my money elsewhere. My track times did not improve at all.

good luck, Ed

undercoverz-28

i have all the basics. CAI, headers, 3" exhaust with no cat and underdrive pully. well at least that everything done under the hood. after the rockers i plan on new gears (most likely 3.90's) then cam then head work.

Compstall

iTrader: (5)

I also dyno'd mine. Gained 7 rwhp and 2 lbs of torque peak.

Ed Wright

iTrader: (1)

How long between tests? Was the car moved from the dyno between tests?

thesoundandthefury

iTrader: (3)

Are you talking stock as in the longblock is untouched but it has bolt ons, or BONE stock as in the rockers were the very first thing you did to the motor?

Compstall

iTrader: (5)

Ed, the way you did yours was probably the most accurate. I have dyno'd nearly all my power mods individually, albeit not on the same day. I'm sure the 2 lbs of torque was negligible, as you could make that up by snapping the throttle a little harder, etc. 7 rwhp was the peak gain I saw on my car. Many people on the net talk up 10-15 hp w/ a rocker swap, although I've never seen a true before/after dyno; that's why I do my own dyno testing to see the real gains. In my experience, as you've probably seen yourself, I've gained on average roughly half the hp at the wheels that all the manufacturers claim. I'm suspecting they advertise their gains based on blown stroker motors and big blocks though.

Ed Wright

iTrader: (1)

I'm talking the original 120,000 mile engine, that had never even had the valve covers off. Stock exhaust, 3.23 gears, stock converter, etc. Only PCM tuning.

Changes that small need done same day, without moving the car off the rollers. you can take a car off, and put it back and often get different numbers, due only to slight changes in alignment with the rollers. The weather stations that comes with these dynos, and weather correction software is not as great as some would like to believe. Very small changes, tested on different days may or may not be accurate. You don't really know unless you make the changes with the car on the dyno, after making three or four baseline pulls in the original configuration. Then four or so pulls with the new parts, and average the pulls both ways. Coolant temp is so critical to the LT1/LT4 (or any iron block engine) as well as intake air (with any engine) power output that those have to be the same before and after the changes also. Otherwise you don't really know where you are. I would not bother with rockers until I had it apart for the cam.

thesoundandthefury

iTrader: (3)

Thanks for the response Ed. The reason I was asking about this is because to my understanding, however well a higher ratio rocker will benefit an engine's power curve depends on how well the engine is able to breathe. In most threads I've seen where somebody was reporting dyno gains after installing a set, you can look and see that they did this after having already installed other "breathing" mods like CAI's, bigger thottle body, headers/exhaust etc. However, conventional logic (law of diminishing returns) dictates that the more bolt-ons you install, the less gains per mod you will see in relation to what they are advertised to give. So in other words, if you were to bolt a catback system onto a bone stock car, you might get 15rwhp, but if you were to bolt a catback system onto a car that already had all the other bolt-ons, you'd probably only see about 7. But with rockers, since their ability to produce more power seems to depend on the engine's ability to move more air, I'm wondering if this might be the one bolt-on mod whose ability to increase power works opposite of all other bolt-ons? (I.E.- less power with no mods, more power with more mods.)

Your thoughts?

thesoundandthefury

iTrader: (3)

LilSlo1

iTrader: (3)

Is this on a LT1 ?? cause a 1.6 ratio rocker on a LS1 would decrease lift and duration and lower power.

undercoverz-28

'97 Lt1

edlt1

Yeah I have a 96 lt1. I have a set of cranes energizer 1.6 rr sitting around. Everyone said to not bother putting them on because the power increase wasn't anything special unless you have some internal work done.

But I wonder if it would be a good idea to throw them on now since I am doing a 100 shot? Would it be a little easier on the motor?

Do I need different valve springs even though its a stock cam and everything?

undercoverz-28

easire on the motor...i would think not.
different springs...not usually.

Louvit

I hear that 1.6 rollers on stock springs may cause spring bind and go kaboom