Just wondering about the long term reliability of these bolt ons, better to just get a bigger cam ?

Mark

 

There are a few guys running 1.8 rockers on the forum and so far no problems, I'm going to install a set of Harland Sharp 1.8's when I do my head/lifter swap. I am already running a mild Comp Cam and these should be a nice addition to the setup.

 

They are 1.8/1.85 rockers not lifters

I am curious about this as well

 

It was a typo! Thanks for pointing that out!

 

Katech always runs with the simple SLP 1.85 and they can run anything. My guess less moving parts, less problems, more reliability. Probably, not worth the extra 5 h.p. for the roller tip. I am researching myself. One guy has had the Crane roller 1.8's on for 30k miles, however, I am still leaning toward the SLP's. Five h.p. means nothing if you grenade a 25k+ motor.

I had two sets of very high dollar roller rockers go out me on two different motors, but this was quite a while back(Six and fourteen years ago). Each cost over 50k to build(1990's money).

917 Porsche Racecar Motor, Enderle Rockers

600 CID Port Injected Ford W/ Hemi Heads, Crower Rockers

So far on my list is Jesel, Crane and SLP. The others I found, have had problems. The new C6 Z06 apparently runs a 1.85 SLP type.

 

30k miles and three years on my CompCam Pro Magnum 1.85s.
50+ 1/4 mile runs a year, no problems here.

Good Luck!

 

What length pushrod? Do they they fit under the stock valve covers? Price? Tuning issues? TIA

 

Using CompCam hardened 7.400 pushrods (stock length). These are adjustable, so hitting exact length on the pushrods isn't as important with non adjustable rockers. If I still had non adjustable rockers I would have used a pushrod length checker after installing the heads and cam to determine the exact length needed. However for all but the monster cams and or really high compression heads, the stock length seems to work for just about everybody.
After the cam I adjusted these to zero lash (unloaded) and got her going but running rough, they needed to be readjusted after the lifters got loaded, which I didn't know. So they require just a little bit of knowledge and effort to get tuned right, not much at all, but that means you have optimized your valve train geometry, wich rocks!

Much thanks to Dennis at The Vette Doctors for the lesson in rocker adjustment. Still need to get a good remote start unit for doing that.

Hope that help some... Good Luck!

 

Running 1:8 Jesel's for 2 years with Comp Cam. total lift .566 intake & .569 ex. Had to clear valve covers in couple areas to clear, not a big amt. No probs & great power adder.
Fred

 

IFLUBYU, Did they fit under the stock covers? Also, Thanks.

 

Aye, there's the rub!

No they did not, and it's the only fault I can find with CompCams. When they came out with these they claimed they were direct bolt-on replacements with no modification necessary. Well.... They will bolt on, and the valve covers will bolt on top of them, no problem... Until you start the engine! Then they "plink" up agianst the baffles inside the valve covers and on some of the bolt nubs. See the website in my sig, pic on bottom of page shows my modified valve covers. Not really all that much work to make them fit. You can also by spacers (ThunderRacing) for about $two-fitty. You don't wanna know what a set of raised valve covers goes for, it's ludicrous.

The SLPs are reported to not need clearence work, but performance gains are reported negligible. The Crane set I have been told by two people clear and give nice gains. I have been following the rocker threads closely for the last three years, and after hearing all the this/that, am quite satisfied with my setup. I would still like to give Compcams a kick in the shins for that one, but... I am a Network Engineer, when I design something, if I say it fits it fits! I have since learned that Automotive engineering isn't quite the same, where it fits until it doesn't then you make it fit, and that's pretty much the norm.
But I was so much older then, I'm younger than that now...

Hope that helps!

 

I too have been interested in SLP's 1.85 ratio. And from the amount of research I've done, there are a few things that I found important.

If one goes with the 1.85's then it's important to also change out the stock valve springs, retainers, etc. since the stock springs will have a decreased life expectancy with the higher ratio. SLP also offers an upgraded spring kit, but you'll also need the air compressor set up and spring compression tool to accomplish this...an added cost if you don't have or know someone that already has those tools. If you forgo upgrading the springs, your car will be okay for a while, but eventually the stock springs will need to be replaced, so it's a pay now or pay later approach.

Installing the SLP rockers themselves is a peice of cake since SLP also makes the OEM 1.7 rockers. From what I understand, it's easy to get the 1.7 and 1.85 rockers mixed up if there sitting side by side, and the only thing that seperates them is a red marking dot on the 1.85's. Both versions install the same way. Just bolt them on and torque them down with no adjustments needed. (I have had my 1.7's off and put them back on and it's a snap and is really easy compared to the "adjustable" rockers I once tried out.)

Cost is the issue though. I've seen reported gains of around 18 hp from just the 1.85's, which in theory are simply nothing more than having a mild cam installed. I know a cam is cheaper, but for me, it would be better to go with the rockers since my internal engine mechanical ability is somewhat limited, and a cam swap in my garage is a little scary to think about. (I do all of my own work, not because of money but because of self-pride.)

I will eventually go with the SLP 1.85 set up basically because of the things I have found in my search. Naturally, though, what is best for me doesn't mean it's best for someone else...

Oh, and if one decides to go with a cam later on, the 1.85's will have to come back off as they do not work with most of the cams on the market, and you'll have to revert back to the stock 1.7 ratio. This rule, however, doesn't apply to ALL cams, just some of them.

 

You can have CompCams do a custom grind cam for no extra charge with lower lift to cover this. Just so happens they made an LS1 cam with 220/224 and 530/534 lift, which dovetailed just right with my 1.85 rockers, giving me around 577/581 lift total, which was just what I was looking for. But yeah, if you were dead set on getting a G5X3 then the rockers would have to revert because the lift would be too high, or you could assume it would be, seeing as they won't tell you what the lift is (still cracks me up). But other than going with a tuner shelf cam, you have no worries.

 

Would the lower lift cam and rockers yeild more power??? Or increased drivetrain reliability? Or both? I know the high lift cams bring crazy power up top but if you wanted the power to come on lower on the rev band, would rockers and a mild cam do the trick?

Thanks,

 

I don't believe there is much difference where the lift comes from, the power output would be pretty much the same. I do think a good set of roller rockers even at stock ratio is a good improvement, reducing valve train noise, smoother valve operation. Some people have claimed small hp gains just going to 1.7 Yella Terras, who knows...
I will state though commenting at this point I am making inferrence from other experience and info I have gathered on the way. I am not an expert and dont do this for a living. I would always suggest you talk to one of the better known tuners directly or CompCams help line. I can't say enough about the help line, it is damn handy.

 

I have a 98 with ls6 intake and cam.I just installed the SLP 1:85 with PRC dual springs. The spring install was more frustating then the head and cam swap I did. The spring compressor tool is the biggest problem. The one I was using was dangerous. The tool would let go and the spring would go flying.

I took the car out and it runs great. The tires break loose it third gear at 55 mph. NO valve cover clearance problems. I am going to install an ASP underdrive pulley. After that, I will do another dyno and post the results.

 

Great pictures. Did you punch the valve covers or did you remove material? Or both. The SLP 1.85's are no long available.

 

Would be nice to see a before and after dyno, any chance?

 

I will do an after dyno but It will include a ASP underdrive pulley.

I will post the results.

 

Skoggins Dickey also now has a 0.5" valve cover spacer, which I understand to be less prone to leaks as the taller ones on the market. I have been researching the Cranes myself. They look to be a good rocker, but I don't want to remove the baffles so I would go to a spacer. The 0.5" spacer will also allow you to use your current spark plug wires.