vetteman8924

hi everyone im new here and have a question to ask i have a 1989 vette stock automatic i was thinking about ordering the 1.6 stamped roller rockers from summit but was not sure about beig able to run them? any help would be great!! also if you can run then what kinda of power am i looking at?

clf93lt1

I would get full roller rockers , not stamped. 10 to 15 hp.

Corvette Kid

And upgrade your springs a bit too. If for no other reason, you're now asking older and somewhat fatiqued springs to work harder now.

vetteman8924

ok thats what i was woundering thanks a bunch

BADDUCK

If you want a full RR for a reasonable price check out www.jegs.com
Look at their house brand. You can get LT4 springs that will work on our 1989's at GMPP for under $30.

CFI-EFI

Particularly for a mild,daily driver, that you don't wind too high (with a TPI?) too often, the stamped steel rockers will do well and cost a whole bunch less. The power gain from the roller (needle) bearings is negligible; the cost isn't. If you can't get them as the self aligning rockers your 113 heads use, you will need "real" push rod guide plates and hardened push rods. The above advice on the springs is golden.

RACE ON!!!

JAKE

CompCams sells full 1.6 roller rockers that are self-aligning, but, they ARE a bit pricey. How is it I know? I just ordered a set.

Jake

65Z01

Your stock '89 rockers are self-aligning and have non-hardened guide plates that must not touch (was "tough") the non-hardened push rods.

Since I had to remove the rocker studs anyway to remove the stock guide plates, I chose the Comp Cam ProMagnum 1.6:1 non-self aligning RR, hardened push rods and hardened guide plates. Combine these with the Comp Cams 981 springs and you have a very nice RR setup.

Of course a new set of keepers is in order too.

Though it's off the topic, since you're new here, have you removed the frisbee from the front of your water pump pulley??

JAKE

Did you mean ". . . must not touch . . . instead of tough?

If so then you're recommending removal of the factory 'guide plates' when installing self-aligning roller rockers, Right?

I just ordered a set of CompCams aluminum 1.6 self-aligning roller rockers and I want to install them correctly. Also, I'm thinking of going with CompCams "BeeHive" springs. What's your opinion of them?

Working on my new LT1 involves a whole new learning curve.

Thanks for your help on this.

Jake

BADDUCK

I don't want to put words in his mouth but I think he is saying he converted to non self aligning RR's on his '88. You should be able to just install the aluminum SA RR's. It would be a good idea to install new springs. You can get 16 new LT4 springs from GMPP for under $30. With a stock cam you can use your stock push rods.

CFI-EFI

The '88 uses the 128 heads, doesn't it? Those heads should have non-self aligning rockers with "real" guide plates and hardened push rods, stock. All they should require is the new, non-self aligning replacement rockers. All the 1989, 113, heads would need is a set of self aligning rockers or, if changing over, the plates and rods as I outlined above.

RACE ON!!!

BADDUCK

Yes, all the 1989 needs is SA RR's and springs are a good idea. I think we are getting several different setups involved in a thread about a 1989. This just tends confuse the issue.

BTW, I think the 1988 uses the D port heads so my impression was 65Z01 was converting but maybe I misread what be said.

Randy93

For a person just getting into RR's, what is the difference in self aligning and non-aligning RR's?
Is it, that you do not have to adjust self aligning?

Sorry, not trying to hijack, just understand.

TIA

Aardwolf

The 113 head started in '88 from what I remember. With non self aligning you need to install guide plates etc if your heads don't have them.

65Z01

Sorry for the typo; yes my '88 has the #113 D-port Al heads. If the stock guide plates contact the push rods when going to 1.6:1 ratio with self-aligning RRs there could be excessive wear and/or binding. Since I felt it was necessary to eliminate that risk by removing the stock guide plates, it was easier to simply go with non self aligning RRs.

You may be able to remove the stock guide plates and machine them open to clear the push rods. Though I installed 7/16" ARP rocker studs I wanted the guide plate thickness under them to avoid any potential stud height issues upon installation of the new RRs.

Since I didn't pull the VC till all the parts were in my hand I never actually measured clearance between the stock guide plates and the push rods to see if there would have actually been a problem with using self aligning RRs. I simply avoided the potential issue.

Though I have no experience with them, I think the beehive springs should be fine so long as the specs meet the requirements of your application, i.e. on a LT1. Read the spring specs and do the math to see if you can get the installed height to achieve the desired seat force and check out the over the nose force with your setup.

You will of course need new retainers and keepers with those springs.

The push rod slots in or Al heads are wide and so do not keep the push rods from moving from side to side. Should the PRs move in such a way the rocker arm might pivot around the rocker arm stud enough that the rocker tip could slip off the valve tip. You can likely imagine what kind of disaster this could bring.

So there are several options
1) use narrow slots in the head to keep the push rods from moving laterally, this is done in the early L98 iron heads
2) put little tabs on either side of the rocker arm where it contacts the valve tip to keep the rocker tip over the valve tip, this is the self-aligning rocker used on the Al head L98s
3) use guide plates that have narrow slots that keep the push rods from wobbling from side to side, here you must use non self aligning rocker arms as I did on my installation.

Our #113 heads on '88-'91 L98 (and I believe the earlier, late '86-'87 #128 Al heads) used non hardened guide plates to roughly hold the push rods in place during engine assembly. These guide plates are not hardened nor are the push rods so there must be no contact between guide plate and push rod during normal engine operaton.

CFI-EFI

Apparently I was wrong in what year the aluminum heads changed. I didn't mean to introduce another factor into the subject, 1989 thread. I meant to be clarifying, not adding confusion to the topic. That is why I included the casting number with what was needed. In review, the 128 heads (1986L-1987?) have true push rod guide plates with hardened push rods. They use non-self aligning rocker arms. The 113 heads (1988-1991?) have non-functional, assembly line aid, guide plates. Therefore the push rods are not hardened and the 113 heads use self aligning rocker arms.

As 65Z01 points out, there must be a restraint, somewhere, to keep the tip of the rocker arm aligned over the top of the valve stem. Chevy has used each of the three methods he lists. It is important not to use any more than one of the three methods in any one engine.

RACE ON!!!

vetteman8924

no it is still on their should i take it off? and also i ordered comp cams stamped roller rocker setup with new pushrods hope that is all i need other than springs..

JAKE

What are stamped roller rockers?

Can you post the part number so I can check them out?

Jake

vetteman8924

they are a rocker arm that just has a roller tip. i got mine from summit comp makes the ones i got
http://store.summitracing.com/egnsea...115+4294863040

65Z01

If you remove it you will free up about 10chp and it's free. The story is on my site.

IMO, though cheaper, the roller tip rockers are not as effective a power adder as full rollers due to the remaining drag at the fulcrum.

So long as you are "in there" I suggest you drop another ~$50 at your local Chevy dealer and pick up a new set of valve seals. The top O-rings will likely shatter when you remove them anyway.