rocker arms

[speedsters9]

Anyone out there know of a good set of rocker arms that would improve the preformance of my f22A? I've heard that a good set of rocker arms will improve performance as much as changing the cam without the added work. I'm not looking for a radical change, mostly over the 2000-6500 rpm range and on a daily street vehicle.

thanks

[blazinmiller]

Maybe I should shut my mouth cause I'm new to working on honda's but I personally haven't seen a overhead cam engine that has rocker arms.

What's there to rock? The cam is above the valves eliminates the need for lifters, pushrods and rocker arms.

Cam to bucket to valve.

IF you had a pushrod engine, a higher ratio rocker arm would in fact increase your valve duration, just like a higher duration cam.

In my "other" ride, going from 1.5 to 1.6 ratio rockers is one of the popular tricks to add HP/TQ without doing much work or spending much.
Pushrod engines are so easy to work on, especially when the valvetrain is all roller.

[speedsters9]

The rocker arms are on shafts which ride above the camshaft. The one end of the arm rides on the lobes of the camshaft and the other against the top of the valve stem. I'm checking with a speed shop to see what they have... seems like allot of stuff is for Civic's, ludes, or integras.

I would think if the shape of the rocker arm is altered from stock it would change the duration of the opening and closing of the valves. I'll let you know what I find out from the speed shop.

[blazinmiller]

Your talking about your bucket/shim setup.
Once again, new to honda's but the last OHC engine I worked on, you couldn't do what you explained. The shim is what controlled the tolerences in the valve.

The end result was when you do a "valve job" you are actually measuring the tolerence and either adding a thinner or thicker shim to get the valve back in spec.

SO putting that into your "rocker arm" theory ,you'd be adding thickness to your shim, thus putting your valve out of spec.

Not the same as adjusting the ratios on a rocker arm to keep the duration open longer.

I can't wait for someone to chime in to correct me, I'd really like to know if these honda engines are similar to other OHC engines I've worked on.

Now if I can just find that damn manual I have.

[HONDA_99]

honda doesn't make OHC engines, only SOHC and DOHC
Here is picture of SOHC, it may be small but you can see camshaft on top and rocker arms on both sides of camshaft going to exhaust and intake valves.

[blazinmiller]

OHC means overheadcam, if you have single, double, or quad that's your deal. OHC still means OHC.

Thanks for the pic. I thought about this more last night and your pic explains what I was thinking last night.

A SOHC engine would have to have rocker arms, the whole time I've been thinking of a DOHC setup.

DO you have a pic of a DOHC setup? I bet the DOHC setups have the bucket/shim setup.

[HONDA_99]

cut out picture of S2000 engine



X-RAY picture of RSX typeS engine



here is article with great pictures about adjustment of valve lashes on RSX typeS engine, you might have to sign up to view article.
http://www.vtec.net/articles/view-ar...&page_number=1

[blazinmiller]

Look at that.
From these pictures even on the DOHC engines they use rocker arms.

Honda offsets their valves even on a DOHC setup.
THe last DOHC engine I owned, each cam was directly above each row of valves. Don't see how more moving parts is better but honda knows what there doing obvisously.
I bet it has something to do with the machanics for the VTEC engines. Or maybe through R & D, this is the best way to do a OHC setup.

Thanks for the pics and proving me wrong.

That article was pretty good. Looks like honda valves are ajdusted without the use of shims. There's a simple adjustment screw.

I'll be adjusting the valves on my 90 EX real quick like.

[JoeK]

I have a question for you blazinmiller. Maybe you can answer this after you adjust the valves.

I adjusted the valves on my 92 Accord and checked them several times. At first, I followed the spec. Then, after running the car, I left them on the tight side. Both ways, I can hear them ticking - not loud, but I can hear them. I put them back to spec since they tick lightly anyway.

I know that some lifters always tick a little but I'm not familar with how the Honda should sound. Is this normal?

Thanks.

Originally Posted by blazinmiller

Look at that.
From these pictures even on the DOHC engines they use rocker arms.

Honda offsets their valves even on a DOHC setup.
THe last DOHC engine I owned, each cam was directly above each row of valves. Don't see how more moving parts is better but honda knows what there doing obvisously.
I bet it has something to do with the machanics for the VTEC engines. Or maybe through R & D, this is the best way to do a OHC setup.

Thanks for the pics and proving me wrong.

That article was pretty good. Looks like honda valves are ajdusted without the use of shims. There's a simple adjustment screw.

I'll be adjusting the valves on my 90 EX real quick like.

[HONDA_99]

you might hear fuel injectors, fuel injectors are make slight ticking sound.

[blazinmiller]

I'm not too familiar with honda's yet either but I wouldn't worry about it if your valves are in spec and you maintain it.
Generally speaking, these engines seem to be able to take neglect better then almost any other engine out there. I don't know how many stories I've heard of women (And even some men) missing oil change intervals, no tune ups, all the while running the piss out of them. This seems to be true for all generations as well.

I figure if I change the oil every 3K, tune her up, and adjust the vavles even 50K let alone 30K there should be no reason I can't get 200K-250K miles out of her.

Maybe this will make you feel even better.
I bought a S-10 blazer at 96K miles for a good price that had a bunk 4.3 in it, it spun a piston bearing at around 30K miles. It wasn't until 112K the engine finally died and it didn't even die from the spun bearing, well sorta.
The head finally cracked from being under so much compression from 30K to 112K. The piston bearing was still fine, very worn but still functioning.
My point of this story was to say that if you start with a good base, they can last forever if you take care of it and follow the manufactures rules, even being somewhat damaged.