BlackBird97

Well, I've had some valve train issues, so I think I'm going to have to pull apart the top end of my motor. *Last thing I needed now* One of my buddies suggested that since I would be doing all this work, maybe I should swap out my cam as well. I didn't think much of it at first, but then after a few days of pondering, it seemed like a good idea. I've been looking around, and I really don't know what the heck I would go to. The CC503 looks like it could be good, but I'm still not sure how well it would go with my current modifications, AND if it would be the best bet for long lasting performance. So this cam shaft would be IT, until the engine were to blow up. If anybody had any suggestions, or any experience, your input would be greatly appreciated. My mods are

-1.6 RR's
-GTP Stg 2 Heads
-Jet Hot Long Tubes
-Full exhaust
-2800 Stall
-Shift Kit
-STOCK BOTTOM END
-Port matched intake
-52mm TB *Hopefully soon to be upgraded to 58mm*
-LTCC
-Tons of other bolt ons

There is a lot of other stuff, but I this is all I can think of that may pertain to what cam to get. Thanks much!

DirtyDaveW

I used the CC 224/236 to go 12.00 on motor and 11.1 @ 121 mph with a 100 shot. It has great lope and a solid performer from an off the shelf cam.
Spec's with 1.6 rockers.
224/236 .537/.556 112 (Xtreme lobes)

What valve springs are you using?
Here's what the CC224/236 sounds like at idle when used in conjunction with long tubes and a Borla XR1 muffler(no cat).
http://www.taekwondoplus.org/z28/224Idle.mpg

JAKEJR

Dirty's is an excellent cam choice. It's basically one step up in duration from the HotCam you're now running but also has faster, more aggressive ramps and greater valve lift.

Should give you a nice mid-range and top end boost without sacrificing much, if anything down low.

Tell us about your valve train issues.
Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

slowZ

I went from the hotcam package to a cc 280xfi 230/236, i'm thinking i should have went bigger.

BlackBird97

Well, about 3 years ago I had a set of heads put on my car and I just started noticing a bad ticking sounds from my passenger side valve cover, so I pulled it off and took a look. The rockers are mushroomed on the edges, the spring retainers look like that have a grove etched into them, and the roller isn't even touching the spring. Turns out that they put in springs retainers that were meant for non self aligning rockers, and currently I have the GM 1.6's that are self aligning. SOOO, needless to say I was furious, and wanted to complain to the very very *reputable shop* that installed them, BUT it had been about 3 years since the work was done. So it would have done nothing....and on top of it, the bastards broke off the base of the studs that hold on the valve covers into my head.

So they ruined my rockers, screwed me on a set of non compatible retainers, screwed up my heads, charged me money for it, and making me do it all over again. Sorry for the rant, still a little ticked bout it.

So now I'm debating on pulling off the heads, putting on a different set of springs retainers and rockers, rods, and replacing cam. Or trying to replace the springs and rockers while heads are on the car, and just sticking with the old trusty Hotcam. I don't know what to do, I don't have a ton of money to spend, but I don't want to half *** it either.

DirtyDaveW

I feel your pain.
I had something similar but no shop did it to me. I did it to myself. I, too, used the GM LT4 1.6 Roller rockers. I had them from like 1997 and in 2007, I put in a new solid roller cam/springs. I opted to go to the titanium retainers, never suspecting that the shoulders on the retainers would be arching up higher and contacting the underside of the rockers. Like you mentioned, after hearing noise get progressively worse and worse, I pulled off the rockers and saw that they were all chewed up. The machinist told me that the initial lift of the cam was actually pressing the valve open(and sideways) with the underside of the rocker, then the tip would hit the valve stem and open the valve fully. I ended up with some busted valve springs too.

On your dilemma, you can switch the springs with the heads on, engine in the car. That's how I swapped in my first set of springs. It's tedious on our cars with their tight confines but can be done. Since you have the Hotcam, you can go to a less expensive set like the Crane 10308-1
example: http://www.summitracing.com/parts/CR...rt=CRN-10308-1. You might want to swap out the valve seals at the same time since you're in there. This spring kit is complete (Springs, locks, retainers, shims/seats) though I'd recommend (if you don't have them) the L98 spring seats over the shim like material in the kit. The kit should allow lifts of up to
.600 and costs around $160.

On the rockers, you can get some 1.7 ratio Scorpions in a Self Align. That way you could keep your Hotcam and gain a little lift.

BlackBird97

Hmm, well I'm going to keep my hotcam. I've been doing a lot of searches 1.7rr's. What exactly would I need to do this swap? Also something thats really bugging me, what stud size do I get? 7/16 or 3/8? Can I get either one and it will work on my car as long as I have the corresponding parts?

DirtyDaveW

Just make sure you have a spring kit that will allow full lift, without 'coil stack'. You can use the BeeHive style springs..
http://www.pacracing.com/Beehive_Spr...Set_of_16.html
Or the Crane 10308-1...
http://www.jegs.com/i/Crane/270/10308-1/10002/-1#

Both will handle up to .600 lift. Your Hotcam w/1.7 RR would equate to a .558 lift.
On the stud size, your stock heads came with 3/8ths. If you switch to 7/16 studs you have to change the rockers to a 7/16ths as well. I have a set of ARP 7/16" studs, still in the package if you want to get some for half price plus the the cost of shipping. You can also get some of Jegs 7/16ths for a great price drop shipped to your house as well.

BlackBird97

Awesome! Thats some good info! Do you know what are some decent 1.7's? I've read allot about the Scorpions, some people say they are great, other people say they are cheap Chinese made junk. Also, with 1.7's would I still use factory length push rods, or would I have to get longer ones? Thanks so much for your help!

DirtyDaveW

Hahaha... That's what I hear too. You never know what to believe. I thought they were Cheap Chinese Junk when my friend said he'd bought some and then put them on his car. But.. he never had a problem with them. I wouldn't think you'd need custom pushrods but to be safe, check the valve stem pattern. Take off the rocker,put a light film of moly assembly lube on the roller, then gently and precisely place it back on the rocker stud. Adjust the rocker to the right spec...
Usually that entails

• Put the cam lobe on the base circle
• Lightly tighten the nut down to zero lash
• Tightening down 1/4 to 1/2 turn
• Set lock nut

Now turn the engine over so that the valve fully depresses then returns.
Gently pull the rocker off. Where is the little smear on the valve stem tip? It should be across the middle if the pushrod length is correct.
There are some pic's on the net if you need a visual of what I mean.

JAKEJR

Scorpions are made in the USA, says so right on the box. There's a LOT of bad information on the internet; trick is to recognize it when you see it.

I'm running two sets - NO, not on the same engine, LOL

I installed a set of 1.7s on my 388 three years ago and recently, installed a set on my son's 96 TL1 Vette. They're extremely quiet (when guys post about their noisey valve trains I just smile) and really good looking, high quality rockers.

I've lost count of all the posts I've read where guys were pulling out their hair trying to quiet down their noisely valve train. I mean they tried just about everything they could think of try to solve the noise issue. They've changed lifters (think about what's involved in doing that), pushrods, valve springs, valve covers (trying to muffle the sound) different weight oil, but their valve trains remained noisey. Most were running Pro Magnums, but a few were running Crane Golds. One guy thought it was his lifter preload setting procedure and, after re-adjusting the preload a few times with no improvement, he figured it was something he was doing wrong, so too the car to a shop to have them re-adjusted yet again. When he paid and got the car back, after a long time at the shop, noise was still there.

I've run Crane Golds and CompCams Pro Magnums and, to me, and - advertising hype aside - Scorpions look and run a lot better. Once you hold one in your hand you'll see what I mean. Those suckas look and feel like they mean business. They're less expensive too; I bought mine for $222 a set and they come really nicely packaged.

I went with NON Self-Aligning 7/16" of both engines because I'm a STRONG believer in NSA rockers, especially after reading all the posts of failures of Self-Aligning rockers, along with photos of the carnage they caused, one some Forums.

On my engine, with many thousands of miles of use since I installed them, I haven't a single issue. My son regularly pegs his tach and the Scorpions keep coming back for more. I HIGHLY recommend them.

Hope this helps.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

JAKEJR

I've read about two different issues with SA rocker arms.

First is the guide tabs on each side of the roller tip, hitting/riding on the ratainer and not allowing the roller to come in contact with the tip of the valve stem. This is a retainer issue where a differently designed retainer will free-up the clearance needed.

The second was the underside of the rocker arm hitting/riding on the retainer. This sometimes happens even on NSA rockers. The cure here is a longer pushrod which kicks up the pushrod side of the rocker creating more clearance.

I recall back in my race engine building days, and before I knew the correct fix, I use to use a high speed grinder to remove metal from the underside of the Crane Golds. Engines were running 1.625 springs and the mod worked, but wasn't the way it should have been done. Remember, the correct length pushrod is the one that estabishes the correct geometry. So don't get locked in on a specific number, specific length. What works, WORKS!

When looking at rocker arms, I like to see a nice arc on the underside of the arm, not flat or straight as many rockers have.

Hope this helps.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

JAKEJR

What's the part number of the ARP 7/16" studs you have? A friend of mine is in the market.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

DirtyDaveW

Part Number: 100-7101
http://www.jegs.com/i/ARP/070/100-7101/10002/-1

JAKEJR

Thanks for that info. However, we're zeroing in on 234-7206s.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!