Thread: 1.9 Modified Rocker Install

It isn't normal...rocker play isn't supposed to be there.

They might have been high mileage rockers too...I think that was my issue as well.

Originally Posted by bluegtp91

The different number means the ratio.

Modded are just stock rockers that are re-welded to have a higher ratio

Rollers are lightweight rockers that are way easier on valvetrain parts...but you pay out the ying yang for them.

i like the idea of roller rockers and the numbered ones with the higher ratio but im pretty sure u have to modify something to use the higher numbered ones probably. but quick question. what made u choose the ones u have?

Choose the ones I have? I have my factory 1.60:1 rockers with #130 springs/titanium retainers. And you only have to get stronger springs/retainers when you get any rocker ratio above 1.84:1.

Sorry for the late reply, telephone line issues. I spoke with Steven at ZZP, after we played phone tag for a while and he said it may be a lazy lifter. He said the rockers aren't usually a problem and any bad ones would be replaced. I added some seafoam to the oil, to loosen any carbon build up and free any lifters that are sticking. The noise did go away, I've put about 500 miles on the rockers and will change the oil at 1000 miles. Hopefully I won't find any metal particles stuck to the magnetic drain plug. The power is crazy, the only problem is I can't keep my foot off the gas. This is my final engine related performance mod, I'm going to do a few appearance mods and install a system. Now I'll just enjoy the ride and do routine maintenance/repairs. I must say even with the few problems I had, this mod was worth it. I also went to the meet Naioa had in NJ over the weekend and was told my car was to quiet. That statement made my day, had me grinning from ear to ear and made me an official member of the sleeper club. Wanna race? to Steven at ZZP, your an asset to the company.

Glad to hear you got all the bugs worked out man. Get it re-tuned for those 1.9's though as your final mod

Originally Posted by bluegtp91

Glad to hear you got all the bugs worked out man. Get it re-tuned for those 1.9's though as your final mod

This is a response from Will I got last year in contemplating the rocker and Tb install.

On Sat, Jan 24, 2009 at 7:31 AM, <Kissmyss> wrote:

Hi Will, will I need a retune to install a 72mm throttlebody and 1.9 modded rockers.


willoverkill@gmail.com writes:
The rockers shouldn't need retuning, install and enjoy. The throttle body depends on what you'd be installing; the Stage 1 ZZP for example would be fine as it does not modify the area where the MAF sensor is located, however the Stage 2 unit would need retuning as it modifies that area and throws off the MAF calibration. I would recommend the Stage 1, or if you want to do a real upgrade go right for the Northstar kit or a billet 78mm.

The Northstar, 78mm billet and Stage 2 72mm throttle bodies all require retuning. The Stage 1 72mm does not, however it isn't enough of an upgrade that I would recommend it. Go for the Northstar unit and don't worry about the TAC, just a standard TPS adapter is required and all changes required for the Northstar will be retuned into the PCM.

you dont NEED a retune, but with them youll either be able to run more timing or more boost depending upon if you were knocking previously or not.

I just changed the oil and the magnet was clean. The car remains quiet, I still haven't got used to the extra power and my gas mileage increased a little. If only I could drive normal, I'd be able to appreciate the increase. The last and final performance mod has been completed.

see when i installed my 1.95 roller rockers it felt like my car is slower making me think i need a re-tune

I added 1.8 rollers and noticed absolutely O difference. The tune was the same as well. Same boost, same knock tendancies. Not sure about the 1.9's though.

My zzp 1.9s have clicked ever since I've had em. Almost 20k now. And the pair I had on my 97 clicked as well for 50k+

They only make a noise at initial start up, for about 3 seconds or so and the factory rockers did the same. If I remove the oil cap and listen through there I can here them clicking.

im pretty sure its not the rockers that you are hearing but the added pressure of the valve springs closing. doing any sort of upgrading on an ls1 like larger valve springs (higher pounds) or higher ratio rockers make that clicking sound. its really nothing to be worried about and to be totally honest, you will have less side load of the rockers plus the correct valvetrain geometry with the stock moddified rockers and are much stronger then any roller rocker setup. the problem with roller rockers is that as the roller tip "rolls" across the tip of the valve when it starts to open it actually starts to roll from the center of the valve tip to the outside of it causing side load and premature failure of the valve guide. with stock rockers, the rocker tip stays put on the center of the valve stem. on a ls, the norm for hp gains with roller rockers is so minimul that it doesnt warrant the cost and by minimul i mean about 5 whp or less. alot of guys go with the slp 1.85 ratio rockers which are like these stock modified ones but modified from 1.7 to 1.85.

more then likely not. there is alot more to setting up proper valve train then just bolting it on and go. the whole myth about roller rockers are better is most time of the time false unless you are buying high end rockers made for race engines like Jesel or such. if you dont have the valvetrain geometry setup correctly, you'll more then likely hurt performance then gain any. ive never heard of stock rockers breaking in half or cracking unlike after market pieces. a good way to test your geometry is get a pushrod length checker and make sure that the higher ratio rockers are allowing the valve's to close and get a valve spring test which is a very light spring which can be compressed by hand to check the rocker's motion as it wipes across the tip of the valve with some sort of paint that can be easy seen and cleaned.