I have searched through all the forums pertaining to rocker arms, and all i see is info about 1.5:1 and 1.6:1 ratios that will work on the 2.2 ohv. My question is will rocker arms with a ratio of 1.75:1 work with little modification? Will valve clearance be an issue? im am new to engines using rocker arm setups. Here is what im looking at: http://www.summitracing.com/parts/cca-1261-8/overview/make/chevrolet
looks practical to me, same as the stock ones but a better ratio. and cheap!!!
.Nobody I know is running those.they would probably work.but why go through all the fitting issues. I say go with what has been proven on our motors.
well that is what forums like JBP are for. One discovers something and shares it with others so they can reap the benefits also. If no one tries nothing new, no grounds are being broken and you dont have much after market support. Im trying this for the gain i may "possibly" get from a dramatic change in rocker ratio. Hopefully an improvement in the powerband somewhere like installing a performance camshaft. It could be a successful mod with the low cost and ease of installation. Everything from the rockers in the link i posted are the same except the ratio from what i can see. So im just concerned the valves may contact the piston from the extra .25 inches of lift. Before i try this can anyone tell me what the stock valve clearance is?
If no one tries nothing new, no grounds are being broken and you dont have much after market support
So what you're saying is that you expect more aftermarket support for an engine that had barely any to start with. And now that both that engine, and the car it came in is out of production. Is that right?
i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
No need to be a wise guy man, Clearly, you misunderstood. What i said is, if no one tries to get performance out of a specific engine or car, no experimentation will be done, not many parts made, and no information how to improve it. Its up to consumers to create demand for it. For instance a buick park avenue, no one really likes that car and its not worth trying to do anything with, You can look all day long and not find @!#$ for it. The same would go for the drive train if it was exclusively for the park avenue but its not. understand now?
Back to the topic, does anyone have any "helpful" information for me? once i complete the mod, if its successful i will share how to do it and the gains if any.
I say go for it. Install a set on one cylinder and spin it by hand and see if it contacts at all. If not, then install all 8 and fire it up. I cant remember anyone else having tried this size rocker before, but I would search before you buy, just to be sure it hasnt already been tried.
I *think* you will need a self guided version for that motor, I know thats what I have on the 1.6's that I run. (Crane 1.6 full rollers).
I dont know if the older 2.2 motor has roller rockers or not, but you would do well to get rollers. Something like This...
I wouldnt run stamped steel ones, and for not much more money you can get rollers.
I Know that with the crane 1.6s that I have, you need to clearance the valve cover for them, or they rub. This is a 2200 though.
I think experimenting is a great idea no matter what the platform or motor. I wouldnt expect it to open the doorway for aftermarket just as I wouldnt expect much help from a lot of people. Not many are willing to do something different when there are easier and "proven" methods already in existence. I would estimate that my LN2 is making upwards of 300hp right now and its not even done yet; theres plenty of things on it that are already "proven" and a few that are different. (example, its been running e85 for about 800 miles now and there are only 2 others on this site that run it, and only ONE of them runs the stock PCM for fuel; only 2 that I know of anyway)
Whatever you decide to do, I would port/polish the head as well, the ports are itty bitty on these motors (exhaust is like the size of a quarter lol).
"A car just isn't a car without a little blood, sweat, and beers." -- Shadowfire
I could swear I heard of someone running 1.7:1's before; it may have been on the s10 forums. Definitely keep us updated. Like Matt said depending on which ln2 you have you'll need self guided rockers. Also, port and polish is KEY.
"In Oldskool we trust"
Thanks guys for the info, much appreciated. Im going to start rebuilding a separate head pretty much maxed out in the performance area. So i wouldnt be able to test one cylinder first like you mentioned until i pull my head and swap it. but thats a good idea. 43 a rocker?? lol no thanks, the set of 8 im looking at is cheaper then one of those. Im new to rocker arms so i dont know much about them. My LN2 is a 96 motor that has steel stamped rockers from the factory. Why couldn't i replace steel stamped ones with steel stamped ones? And do you mean self aligning? I don't know what that means when it comes to rockers if you wouldn't mind explaining. I dont plan to rev the engine past 6500 rpms so im not going to convert to roller rockers unless i have to. YEAH, the head needs major port modification and i plan to do that also.
The point of rollers it to free up lost horsepower due to frictional loss. Full rollers are they way to go if you are rebuilding. There was talk about 1.75 rockers on the ls forums for sbc engines and 1.71 for 4 cylinders. Never seen 1.75 on any engine yet.
On the inside my car looks like a fighter jet.