I saw a bigblock build up that had 1.7 rockers on it. I dont know much about rockers and just wanted to find out. Thanks!!

PS, I'm a dumbass

------------------
We are the future, the 21st. century dislexyic, glue sniffing, cyber *****, with homicidal minds and handguns.

 

The biggest I have seen is Harland Sharp, they make a set that is 1.65 for small block, just make sure that you have enough clearance for your heads depending on the cam in there.

 

keep in mind, everything that has to do with big blocks is... however ironic it is, bigger. i think i heard of 1.9 rockers somewhere.. even if im mistaken, i know for a fact that 1.8s are out there--also, dont get the idea that incredibly high lift rockers will give you tons of power.. yea 1.6's will help, but put your money somewhere else rather than spending it trying to see how much lift you can get out of your valvetrain

[This message has been edited by mtx28 (edited April 03, 2001).]

 

The 1.7 on a big block is factory standard like the 1.5 on a small block. When you typically go to 1.6 on a small block, the big block can go to 1.8. Other ratios are available but those are thare standard ratios.

Small block rockers are made for a 3/8 stud and big block rockers use a 7/16 stud.

Technically you could use the big block's 1.7 rockers by putting in 7/16 studs in a small block head however the small blocks springs are way to small to handle that type of lift. Also the extra ratio pushes the push rod even closer to the pedestal and the pushrod hole on many factory heads usually isn't wide enough to handle a 1.6 rocker

------------------
Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season

Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

Stephen, I don't think you could put big block rockers on small block heads, regardless of the stud size. The distance from the stud to the valve stem is much greater on the big block.

Comp also makes 1.65s, even for 3/8" studs. They're part # 1103. An enormous variety is available from Jesel for shaft-mount systems. Most of us don't have to worry about that kind of thing though.

IIRC the stock ratio in the LS1 is 1.8...

------------------
"So many Mustangs, so little time..."
ICON Motorsports

 

CompCams makes them all the way to 2.0 and maybe even bigger; some of the Pro cars run ratios like that.

On street engine, I wouldn't go bigger than 1.65. The geometryand clearances get very critical once you cross that threshold.

A lot of camshaft ramps don't take kindly to those super ratios either. You need to touch base with your cam maker to make sure your particular cam can be run with the big boys.

Jake

------------------
1986 Corvette Coupe, 415 CID, Edelbrock 6073s, ZZ9

 

Changing to a higher lifting rocker is just a poor mans cam swap anyway. The extra lift gained in a street engine can be better gained with a proper cam swap.

Other than going to a small base circle cam to get higher lifts, the rocker swap becomes an option when your current cam is at it's highest lift possible to fit through the cam bearings and you still need more lift. We're talking over .700 lift at the valve.

If I had an all out small block race engine with .600 lift with 1.5 rockers, the cam would be getting close to it's maximum grind. By switching to the 1.6 rockers I could then go to a .640 lift.

Usually if you need higher lift than that, you have to go to a roller cam since flat tappet cams start dieing off with that much lift.