'95-'97 1.6 Rocker Arm Info & How-To

[developed]

I have a '97 S-10 with a 2.2 engine and have been searching all of the net for info on installing 1.6 rocker arms onto my engine. I found this very comprehensive info and how-to over at J-Body.org and here's the link: http://www.ny-jbodies.org/library/en...2rockerarm.htm

GM 2.8L/ 3.1L 60 degree V6 ENGINES
GM 2.2L L4 ENGINES (97 –EARLIER ONLY)

WHERE DO I FIND ROLLER ROCKERS FOR MY ENGINE?
COMPETITION CAMS offers MAGNUM Roller Tip Rocker Arms. Available in a 1.52:1 ratio. Part #1413-12 and 1.6:1ratio. #1414-12 These rocker arms are a stiffer construction rocker arm that have a roller tip that Competition Cams claims a 10-30 hp increase over stock, -due to the increased stiffness and the reduced friction of the roller tip.
CRANE CAMS offers a full roller rocker. It is their GOLD RACE Extruded Narrow Body roller rocker. (For 60* v6 and center bolt v8 engines) it is an all aluminum needle bearing roller fulcrum and roller tip rocker. $$$ Very pricey. It is available in a 1.5:1 #25750-12 and 1.6:1 ratio #25759-12 but require cranes replacement nuts #99795 and studs #99148-12.
All part numbers are for the V6 engine, the –12 behind each number indicates quantity of 12. For the four cylinders purchasing two sets (24 rocker arms total) will work out to enough to do 3 engines, (8 rockers an engine) so if three people went together and bought two sets of rockers you will save some money.

WHAT EFFECT DOES A ROLLER ROCKER/DIFFERENT RATIO ROCKER HAVE?
With 1.5:1 or 1.52:1 ratio roller rockers the benefits are around 5 hp. due to reduced friction. With the 1.6:1 ratio rockers, you’re looking at more hp gain because the higher ratio acts like a bigger camshaft by opening the valve more. Thus allowing more air into the engine. Expect around 10-20hp. Remember be conservative these are estimated horsepower gains – depending on application power increases vary. Just because you swapped in these rockers does not guarantee that you gained 20hp.

L4
The cam lift of the 95-97 cams is .288" the amount of valve lift for the different ratios are:
1.5 (stock)= 0.432" valve lift
1.52 = 0.4377" valve lift
1.6 = 0.4608" valve lift

V6
Cam specs for a 92 3.1L
Lobe lift intake .2626"
Lobe lift exhaust .2732"
1.5 (stock)= .3939"int. .4098"exh.
1.52 = .3991"int. .4152"exh.
1.6 = .420"int. .437"exh.

To find valve lift from any cam when using different rocker arms take the known valve lift example .425" and divide by the rocker ratio 1.5. .425/1.5 = .283333333333 this is the cams lobe lift, then take the new ratio example 1.6 and multiply it by the lobe lift. .283"x 1.6 = .453" valve lift.
Valve lift – the amount the valve opens due to the combined lift of the cam and mechanical advantage of the rocker arm.
Camshaft lobe lift- the amount the camshaft lobe is raised up from its base circle.

WHAT ELSE DO I NEED?
If going with the Comp Cams rockers, The first thing you need to do for this swap is get a set of M10 rocker arm studs from a 2.8 v6, gm part number for these studs is #476530. These studs were sourced from an 89 2.8L Chevy celebrity. At my dealership (in Canada), they retail for $5.55 Canadian each. V6's will need 12, four cylinders will need 8 of them. The threads on these studs are M10x1.5x9.9/M10x1x18 these are a fully adjustable stud that were used on the v6s. These studs will compensate for the different ratio rocker. The stock rocker studs are non-adjustable and are a M10x1.5x9.9/M8x1x.32 the M8 non-adjustable stud will NOT work with these rockers. The Comp Cams rockers come with new 10mm nuts.

If using the Crane full roller rockers then you need to get cranes studs 99148-12 -which have a M10x1.5x9.9/ 3/8x24 stud. In addition, cranes nuts #99795. These studs use have the metric threaded end for the cylinder head and a standard type 3/8 stud/thread for the rocker arm. Don’t forget you can always check the wrecker’s for the GM studs used for the Comp rockers. I purchased six studs for six bucks from a local wrecker.
If installing the higher lift 1.6:1 rockers or installing an aftermarket performance cam along with any of the roller rockers you will also need a set of aftermarket high performance valve springs to accommodate the higher lift.

Comp Cams #’s 980-12 (springs) 742-12 (spring retainers) and 601-12 (valve locks)
Crane Cams #’s 99848-12 (springs) 99915-12 (spring retainers) and 99041-12 (valve locks)

These part numbers are for V6 engines only. However, with a little searching around, some after market replacements could be found for the L4. The stock springs for the L4 engine WILL work with the 1.6:1 rockers. There are a few companies said that these springs will be fine for that amount of lift on the 2.2L. New pushrods are a must, as the old pushrods and rockers have worn specifically to each other and using old pushrods with new rockers can cause premature wear along with voiding the warranty of the rocker arms from the company. Factory (stock type) pushrods will work fine.

*NOTE V6 owners. -Some of the earlier v6’s came with the adjustable M10 studs, some didn’t it depends on year. Check if your engine already is equipped with them before you go and buy a set to find out you didn’t need them.

OTHER MODIFICATIONS?
If installing a set of 1.6 ratio rockers modifications to the pushrod guide plates will have to be made. As the pushrod angle is now altered and will sit closer to the guide plate. An angle grinder with a carbide bit is the easiest and quickest way to do this.


VALVE ADJUSTMENT:
You must find top dead center (TDC) for piston number one. You can do this by removing the spark plug and by hand turning the engine over at the crank pulley until number one is at the top of the cylinder, use a screwdriver in the plug hole to feel the piston. While cranking the engine over pay attention to the rocker arms, if when the piston is moving up towards TDC and both rocker arms are not moving then the engine is on number one firing position if one of the rockers moves while coming up to TDC then the engine is on number four firing position, and needs to be cranked over one complete revolution.

ADJUSTMENT PROCEDURE FOR L4 ENGINES:
With number one piston on the firing position at TDC install the rockers on the studs, adjust the valves for number one cylinder only. Tighten in the adjusting nuts until all lash is removed. This can be determined by rotating the pushrod while turning in the adjusting nut. Once the play has been removed, turn in the adjusting nut one-half turn to center the lifter plunger. Repeat procedure for each cylinder one at a time while on the firing stroke only.

ADJUSTMENT PROCEDURE FOR V6 ENGINES:
With number one piston on the firing position at TDC install the rockers on the studs, the valves that can be adjusted are:
EXHAUST: 1, 2, 3
INTAKE: 1, 5, 6

Tighten in the adjusting nuts until all lash is removed. This can be determined by rotating the pushrod while turning in the adjusting nut. Once the play has been removed, turn in the adjusting nut one-half turn to center the lifter plunger. Now crank the engine over one complete revolution to number four firing position. These valves can now be adjusted:

EXHAUST: 4, 5, 6
INTAKE: 2, 3, 4

continued

[developed]

1.6 Rocker Arm Install For 2.2L

Tools and Parts Needed:

-18mm, 15mm, 13mm deep sockets
-15mm wrench
-A long Phillips or star screwdriver
-8mm and whatnot for to take off valve cover
-New Valve Cover Gasket
-8 studs GM part # 476530
-8 New GM Stock 2.2l pushrods GM part #10198813
-8 Comp. Cam 1.6 roller tipped Rocker arms w/8 Fulcrum washers & 8 nuts
-Comp. Cam red lubricant
-Small grinder (4” disc is all I used) of some sort or good drill bits to elongate pushrod guide plate.
-1 Liter of Motor Oil
-Some medium strength Thread Locker
Installation:

-Disconnect Battery
-Remove Air intake/alternator /plug wire (tape #’s to them so you know where they go back too!)/part of throttle body cover (plastic piece) and finally valve cover.
-Caution: DO NOT DROP ANYTHING DOWN INTO THE BLOCK----BE CAREFUL!!!
-Now remove all four spark plugs.
-Now starting with cylinder #1, use 15mm wrench, turn the crank pulley (by the 3 little bolts, which are 15mm) till you get Top Dead Center (TDC) of the compression stroke. U will know when u get there, b/c just hold your finger over the spark plug hole and you will get Pssssssst of air blowing by.
-Use a screwdriver by sticking it in the spark plug hole to feel the top of the piston. You will see how when you rotate the pulley, it will get to the top of the stroke and start to come back down again. You want it at the exact TDC. It will take a few times going back and forth, to see that you’ve got it TDC. It’s not that hard, don’t worry.
-Now, that you’ve got the valve in the right position, take off the Stover nut (rocker arm nut) and stud for b both the intake & exhaust. However, make sure you do one at a time and place them in Ziploc Baggies so you know exactly where they go if you ever install them again! Same with pushrods!! Know exactly where each one goes, and which end is up. Very Important!
- When taking off stud, it will be a little tuff, but its ok.
- Once both studs are off pull the pushrod guide plate off.
- Use grinder or drill to elongate it about 1/8” (I did and it was more than enough).
- Before installing new stud, clean out the stud holes with a paper towel as best you can.
- Now reinstall, plate with new studs. Using a little bit of thread locker on the stud.
- Torque down to 37lb/ft or just free hand it with about 70/lb on the 6” ratchet, I did
- Lube up both ends of the new pushrod with motor oil and stick in hole.
- Now lube up the fulcrum washer (the edges and bottom) with red lube and put it on the inside of the rocker arm with the nut on top.
- Tighten nut down until the play on the pushrod starts to get hard to turn with your fingers. Now turn it an additional ½ turn and Viola! You’re done one of 8!
- Add some motor oil to the top of the rocker arm where the little hole is.
- Once you’re done all 8, apply liberally the comp cam lube to the roller tipped part. Also, add some more oil to the top of the rocker arm.
- Then reinstall the valve cover and all other parts.

[developed]

wayfastwhitey went in with me and we split a set of Comp Roller Rockers for a V8. He actually got everything, including the studs and pushrods from a local supplier for a good price. He put them on almost immediately and I'm still procrastinating

Here are some things to note: the upper part of the 2.8 V6 rocker stud is 10mm with 1.0 (fine) thread. The pivot and nut that comes with the V8 rocker arms are 3/8 inch (a hair smaller diameter than 10mm).

He found that double-nutting 10mm nuts worked good. Don't use a single nut as they will back out (even with stud loctite)!!! He also said that he needed to drill out the pivot, I believe 25/64" but you need to verify the actual size - I'm just letting you know in advance that they will need to be drilled out.

[wayfastwhitey]

Quote: Originally Posted by developed

wayfastwhitey went in with me and we split a set of Comp Roller Rockers for a V8. He actually got everything, including the studs and pushrods from a local supplier for a good price. He put them on almost immediately and I'm still procrastinating

Here are some things to note: the upper part of the 2.8 V6 rocker stud is 10mm with 1.0 (fine) thread. The pivot and nut that comes with the V8 rocker arms are 3/8 inch (a hair smaller diameter than 10mm).

He found that double-nutting 10mm nuts worked good. Don't use a single nut as they will back out (even with stud loctite)!!! He also said that he needed to drill out the pivot, I believe 25/64" but you need to verify the actual size - I'm just letting you know in advance that they will need to be drilled out.

Be very careful double-nutting the rockers. You can get carried away and open the valve...Don't ask me how I know!....an alternative would be to spike the stud on top of the single nut. That is, take a punch, lay it on top of the nut, and burr one to two threads on the stud. Do this in two to 3 places. You'll still be able to take the nuts off later if you choose, but it will prevent them from backing out. Of course the best solution is to find some locking rocker nuts for the M10x1.0 threads.

[developed]

We have a large auto/industial parts house with a good sized machine shop. I went into there (to the parts counter) and asked for the locking/crimped rocker arm nuts 10mm 1.0 fine thread - had a rocker stud with me. They said they didn't have anything and told me to see the machine shop service writer. He looked for a while on his computer, went to the "parts" (not his inventory) bin, and brought back just what I was looking for . But - he only had 3?!?! He ordered some and they came in the next day - $0.88 each!

[MadJack]

I posted this in another thread, but here's my thread from J-Body.Org concering the 2.2L/2200 rocker arms: http://www.j-body.org/forums/read.ph...=348365#348960.

Another how to for adjusting the rockers can be found at Howell Automotive, here: http://www.howellautomotive.com/inde...PROD&ProdID=15.

And another from JBO here: http://www.j-body.org/forums/read.ph...33542&t=333542.

Hope these help!

[xtrememeasures10]

Quote: Originally Posted by wayfastwhitey

Be very careful double-nutting the rockers. You can get carried away and open the valve...Don't ask me how I know!....an alternative would be to spike the stud on top of the single nut. That is, take a punch, lay it on top of the nut, and burr one to two threads on the stud. Do this in two to 3 places. You'll still be able to take the nuts off later if you choose, but it will prevent them from backing out. Of course the best solution is to find some locking rocker nuts for the M10x1.0 threads.

Or you could saftey wire them!
I work on planes. They use saftey wire and cotter pins everywhere. wish the automotive world would bring saftey wire in.

[dropped94]

will the 1.6's clear the stock valve cover

[developed]

Quote: Originally Posted by dropped94

will the 1.6's clear the stock valve cover

They will on the '95-'97's. The '98+ will need to be relieved.

[dropped94]

do you have to replace the springs

[developed]

No - but as article states, you should replace pushrods.

[dropped94]

stock size

[n8rsk8r]

what did you notice after these were installed? A TRUE increase in power? Was GasMileage up? LOL probably not due to the new found power :P

[Chris0nllyn]

wow way to bring back an old thread....lol...mand yes it makes a big difference, youll get moe power with roller rockers than you will with simple bolt ons

[TubbD]

hmmmm...... I kinda want to do this.

[Chris0nllyn]

i have a set w/ ARP studs i have yet to put on, im debating on selling them......but i dunno

[n8rsk8r]

Quote: Originally Posted by Chris0nllyn

i have a set w/ ARP studs i have yet to put on, im debating on selling them......but i dunno

well if you do, throw them up on here. Depending on money I may scoop em up.

[Toadz]

Quote: Originally Posted by n8rsk8r

what did you notice after these were installed? A TRUE increase in power? Was GasMileage up? LOL probably not due to the new found power :P

I'm also wondering this. Would it be worth it to go with the 1.5 or 1.52 instead of the 1.6 to avoid modification?

[Chris0nllyn]

if you have a 94-97 you dont need to modify anything with 1.6

[n8rsk8r]

Quote: Originally Posted by MadJack

I posted this in another thread, but here's my thread from J-Body.Org concering the 2.2L/2200 rocker arms: http://www.j-body.org/forums/read.ph...=348365#348960.

Another how to for adjusting the rockers can be found at Howell Automotive, here: http://www.howellautomotive.com/inde...PROD&ProdID=15.

And another from JBO here: http://www.j-body.org/forums/read.ph...33542&t=333542.

Hope these help!

Okay, so this set is a whopping $299.99/set!!! Wooohoow

What is the difference between an ecotec and a regular run of the mill engine? Ecotec the flex fuel engine? If so what is the difference between the two?

[Acrophobia1]

what about a 94' everyone leaves out the 94. Will it work.

[Chris0nllyn]

yep

[n8rsk8r]

Quote: Originally Posted by Chris0nllyn

yep

So besides the fuel side of the engine (filter regulator, special filter, rails and injectors (all of which can be swapped out at once with an older intake- if you are set up with the older --non ectotec fuel delivery system--) what is different? Is this why the add says that it is for non ecotec engines? Is there a difference in the head it's self?

Also, I plan on doing a P/P to the head, bigger valve job and installing these roller-rockers, think I could squeeze 30 horses outta this? I am searching for a suitable TB replacement and will do a tweecar RT and wideband O2 once finished. I want to be sitting close to 200hp with this engine. I am going with a mandrel bent dual off of some sort of high flow muff.

Also, what is the most our beloved lil engines have done? 400hp?

The reason I ask I have a 4banger mustang, and with the right set of mods you can be sitting at 225hp N/A. It is a 2.3L, part of the build is stroking it to a 2.5. Is there stroker cranks out there for our engines?

LOL sorry this is a LITTLE off topic. Any help would be great

[Chris0nllyn]

the ecotec motors are completely different from our motors and nothing can be swapped over, 400hp i think could be possible on a built motor....no stroker cranks....

[yo_wasup182]

ya, the ecotech is a 2.2l DOHC moter, and the S series have the 2.2l push rod.

[truckinjeff]

Hey I know I'm diggin up an old thread and I'm not going to start a new one for the same topic, but did anyone know that STS performance has 1.6 roller rockers? I want to know if anybody has them in their tu tu and are they satisfied with them? I'm thinking about doing some work to my motor real soon.

http://www.stsperformance.com/22performance.htm

[Chris0nllyn]

people have been having problems with sts

[truckinjeff]

Quote: Originally Posted by Chris0nllyn

people have been having problems with sts

What happen? Did they break or lock up?

[Chris0nllyn]

who knows....some guys have made payments and havent got the stuff they ordered....ive got some 1.6 comp cams roller rockers in the garage....i used them for 3000 miles then took them off

[cherrybomb_420]

why, what happened?

[AVTekk]

search for STS on the site, there are a lot of unsatisifed customers.

[Acrophobia1]

Anybody ever looked into getting stiffer valve springs or double springs after they did this? If you do that you might need to upgrade your pushrods and spring retainers and basicaly the whole valve train. The reason why I ask this is because our lifters have a spring inside of them. That's how hydrolic roller lifters work. I'll call comp cams and ask them what they think. It's sad i'm asking them when they don't have a p/n for any roller rocker for the 2.2L.

[mattdudley77]

Does anyone know if a rocker arm upgrade will work in a 98 2.2 and if its just a simple swap.

[NevurMind85]

not sure if it will work with the 98+ or not. im trying to find out the same thing.

[Chris0nllyn]

98+ already have 1.6 rockers, they just arent roller tip

you wont see any power increase....just less friction

[cs xtreme]

Quote: Originally Posted by Chris0nllyn

98+ already have 1.6 rockers, they just arent roller tip

you wont see any power increase....just less friction

You sure?

[andyswmr714]

I thought i read on one of the other threads that the rockers are 1.56 not a true 1.6.

[cs xtreme]

Quote: Originally Posted by andyswmr714

I thought i read on one of the other threads that the rockers are 1.56 not a true 1.6.

1.56 seems to be the true ratio

[DMP]

Yeah one of the "gurus" over on j-body.org said the 98+ has 1.56 rockers. GM or I think maybe even the Haynes manual lists them as 1.6 rockers.

[daniel6718]

what about installing some stock 1.7 ratio rockers off a ls1 onto a 98-2000?