question on rockers...

[rurouni20xx]

was digging around morana v6 the other day and happened to look around the other engines besides the 3.0, stumbled upon some 1.8:1 rockers for a 4.0, will these work in a 3.0? just curious since i seen them, and if it did i wonder how much more gains would be had w/ that level of lift...or would they smack the piston?

 

[betomonroy]

You have to make sure you don't end up having coil bind.
This means your valve coils compressing to less than .050 wich will cause the coils to break. Not mentioning the possibility of your pistons hiting the valves.
BUT IF THEY WORK LET US ALL KNOW IMMEDIATELY.

 

[MikeInIdaho]

Yeah, it's definitely good PM to change the valve springs, guides, retainers etc. to components that are more up to the task. Adding better pushrods and lifters may also be in order, depending on the application. You might be OK using stock springs and such with a ratio of 1.8:1, but it's still not a bad idea.

ER rockers are the hot ticket on I,II and III series GM 3800's. The stock valve train can handle ratios up to 1.9:1, but I have heard of valve guides failing with ratios as low as 1.84:1. On a motor such as the vulcan 3.0, which revs much higher and more freely than the GM 3800, it wouldn't be a bad idea to beef your valve train up. Top end is where you'll see the biggest performance increase with the modified rockers, anyways. Good luck!

 

[rurouni20xx]

its going on a turbo 3.3 beefing the valvetrain and porting were already considered, a larger set of lungs would be awesome. anybody know of any oversized valves and seats?

 

[MikeInIdaho]

Off the top of my head, no unfortunately. With a turbo, worked heads and modified rockers that thing is going to scream though. Can we say 7,000 rpm honda slayer?

 

[rurouni20xx]

thats the point, i want to leave the saleen mustang next time, not jump him to 40mph like i can already and get left w/o any top speed or power to pull the rest of the gears. if i can get a wheelstand ill love it even more. the worry on the mustang and v8 chevy owners around here after i jump the line a length ahead and stay there a few seconds is worth it, i want to leave them after i get thru w/ this engine. btw, this is just a stock 3.0 w/ a4ld and stock 3.48 gears and 4wd. shes getting an m50d and a whole lot more. what size dif is there between 5.0 valves and 3.0 valves? i know they make oversize valves for 5.0s, if the 5.0 rockers will work it wouldnt surprise me if the valves would too...ive i have to ream the guides a lil and they are the same length i can handle that, i want bigger faces and seats if i can to help it breathe some more if possible. that should reduce the boost pressure so i can crank some more boost into it. idk, maybe im getting a lil ahead of myself, but if the research shows its possible im going to try it!

 

[rurouni20xx]

okay since i dont have my engine down and im tired of digging around google to no avail, does anybody happen to know the stock length and diameter of the intake and exhaust valve stems? if i knew the those dimensions i may be able to find some close enuff to try in my trk...if i had my motor down id measure them but since the motor is still in the trk i dont have that luxury...lol. thanx for any info.