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Rocker Arm Problem - Do they make better ones?

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KMag

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Discussion starter · #1 ·
New to the forum and new to the 240 sx. I'm looking for some information about Rocker Arms. To make a long story short, I'm building a SR20 and upgrading the bottom end for more boost, but my question is about the rocker arms.

It appears that they have a problem with breaking. I see that they make rocker arm stoppers to help with the problem, but is anyone aware of an aftermarket rocker arm that is stronger?

I searched, but I couldn't find any reference to them. Any info would be appreciated.

KMag
 
#3 ·
the reason people use rocker arm stoppers on the sr is because they are hydraulic lifters. this means that there is not a solid connection and at high rpm there is a chance that they can slip out of place. the rocker arm stoppers prevent that from happening

like the last post asked where did you see/read/hear that they have a problem breaking?

i think you might just be confused about the purpose of the rockr arm stoppers or took someones post/s out of context.
 
Discussion starter · #5 ·
Well this shows my inexperience with this particular engine. When the car was bought it had a broken piston. I don't know how it was broken, was just that way. So we bought a used sr20 and installed it. We are building the broken piston engine to a stonger one.

Last week, the son was driving the car, missed a shift and over revved it ( at least that's how he described it, you know how these kids are today) and broke two rocker arms, and didn't do the cam much good either.

So, if I'm building a more bullet proof engine, is there a better rocker arm out there? Or is the concensus that the proper way to prevent the breakage the installation of the stoppers?

dsmart, what is the purpose of the stoppers?

Thanks for the help

KMag
 
#7 ·
all this talk about the SR rocker arms flying off makes me wanna spend extra cash and get stoppers and not race my car untill i do. Ill be buying a set within the next 2 paychecks. How high do you need to rev the SR untill it becomes Rocker Arm Throwin territory? I only take mine to 7000 and my friend takes his to 7500 without stoppers.
 
#8 ·
once installed they are supposed to prevent the rocker arms from jumping or slipping out of place at high rpm. if your rocker arms broke then it most likely happened after they were out of position. you should check your piston domes and valves on the cylinders where the rockers broke/came out of place. your probably gonna be looking at more damage

because they are hydraulic low oil pressure does not help as it allows more freeplay in they system.

if you have good oil pressure and rocker arm stoppers installed then you shouldnt have this happen again.
 
Discussion starter · #9 ·
So, I am then assuming by everyone's reply's that there are not any aftermarket high performance rocker arms made? And that the stoppers are the only solution to the problem?

The rockers arms were broken in engine #2 that's still in the car. I'm working on engine #1 that does not have any damage. I am looking to prevent this same type of problem in the engine I am building.

I have built many performance engines, this is the first SR20. I have not seen this happen in other motors, and also want to know if what I heard, that rocker arm breakage is not uncommon?

Thanks so much for your posts!

KMag
 
#10 ·
tough break for your friend touge... makes the $70 bucks for the stoppers look pretty cheap.

i sold my dirtbike to some asshole who had a 4stroke one that was the same colour as the 2stroke one i sold him. the day he bought it from me he loaded into the back of his truck beside the other one and drove to the gas station. he filled up both bikes with straight gas and when he rode it for the first time he cooked the brand new engine i put in it. i told him many times that he needed to mix the gas for it but he said because they were the same colour he forgot they were different bikes. pretty much a pointless random story but the moral is

oil is cheaper than pistons - rocker arm stoppers are cheaper than motors
 
#11 ·
KMag said:
So, I am then assuming by everyone's reply's that there are not any aftermarket high performance rocker arms made? And that the stoppers are the only solution to the problem?

The rockers arms were broken in engine #2 that's still in the car. I'm working on engine #1 that does not have any damage. I am looking to prevent this same type of problem in the engine I am building.

I have built many performance engines, this is the first SR20. I have not seen this happen in other motors, and also want to know if what I heard, that rocker arm breakage is not uncommon?

Thanks so much for your posts!

KMag
Click to expand...

the rocker arms broke because they were not in position and probably got thrashed. they are not weak and i would bet that if you ask people with high hp sr's they are running stock rocker arms.

there may be aftermarket pieces or you could have something made but it would be like having your head ported...its just not needed till you are looking at over 500hp
 
Discussion starter · #12 ·
Thanks dsmart,

That's the info I'm looking for. If OEM rocker arms are regularly used for high HP SR20's, that's all I need to know.

I'm expecting to put down 400-450 HP. At least, that's the goal. Still lot's of planning ahead. Now onto valves, springs and cams.

Thanks for the info.

KMag
 
#13 ·
The comments about good oil pressure and RAS's are correct. The design of the OE rocker arms doesn't allow for easy breakage IMO. If you absolutely have to do something with the arms themselves, pay for some new ones and have them cryo-treated. But this is a waste of money that could be spent elsewhere, like on a new oil pump/front cover and RAS's.

Good luck,
Andy
 
#16 ·
i just got some rocker arm stoppers off ebay for half that much from some guy in texas that makes them and they look great. i was wondering how hard these things are to install though, ive read some faqs on how to install them and how to grind some stuff off the valve cover for the s14 sr's but i was kinda wondering if your in danger of really messing something up if u dont do it perfect? i guess i'll find out soon enough, but any tips from anyone that has installed them would be nice.
 
#17 ·
Generally the fingers and flanges point downwards towards the rocker arms, you line the holes in the RAS up with the holes for the screws that go onto your camshaft bearing / bracket things, and the hole for the oil tube as well. So order is camshaft, cam bearings on camshaft, then the RAS on top of cam bearings, then the oil tube. Then your cam bearing bolts go all the way through the bearing ras and tube.

Tighten it down and your good to go, you would have to try pretty hard to do it wrong. you should be fine :)

sr240dett3 said:
Yea maybe you are having problems with them breaking because of installations...

Are you using Specs to install them (tightening etc) like a FMS …
Click to expand...

You do realize there is nothing to tighten down right ? Ever looked at them ?
 
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