BluelionZ28

I have a '97 Z28. The Lt1 is pretty much completly after market but the Rocker arms. I recently broke a Valve spring and bent a valve, that problem is fixed. Now I am trying to figure out what is the most cost effective way of topping it off. I was gonna use the rocker arms it has but the guy that i bought the car from said that they dont seem to be tightening down right and may slip off. What is the best way to solve this problem. Also the current set up is for the 3/8" and 1.5, Are the chances of them Breaking as high as i am guessing. Please help I need to get this car back on the road and reliable. Ty

RamAir95TA

iTrader: (2)

Your post is missing lots of information. When you say "completly after market", what do you mean? You should be specific on what mods are done to the car so we can help identify any weak links, if any.

What do you mean by "cost effective way of topping it off"? If I were you, I would replace the stock studs with 7/16" ARPs and 1.6 rockers (be it Pro Magnums, Crane, etc.), assuming your valve springs can take it (what springs are you running?). Also sounds like your guy just doesn't know how to set the valve lash.

Lots of questions to be answered here. Be specific.

BluelionZ28

I am gonna get the rest of the information and post ASAP

BluelionZ28

Ok this is just some of what the car has done to it.

Engine
LT1, Bored 30 over, Comp 306 Cam, Titanium Valves, Trick Flow Push rods. Forged Pistons, Port and Polished Heads, Intake Bored 2", Exhaust 1.55", Holley Throttle Body, Hooker Headers, Excel Opti spark

Trans.
T56, Steel Shift Forks, Carbon Fiber Sync, 2.97gear set, B&M Short Throw, SLP clutch, SLP 3.73 Rearend

Susp.
Edel. Torque Arm, J&M Control Arms

So that is Pretty much it beside an electric water pump, better fans, Oh and a Edelbrock Performance Intake, I am sure there is more, Larger fuel injecters.

So will just a set of good rocker arms hold all that engine stuff togeather, where is the weak link if you see one?

BlackBird87

iTrader: (6)

Very weird that it would still have the stock rockers in there, but i would switch to 7/16 arp studs and 1.6 roller rockers

SoxXpupPeT

iTrader: (34)

Agreed! 3/8" rocker studs can "flex" at high RPM. causing the rocker to change the pushing position on the valve, and causing it to bend like it did in your case. 7/16" studs would prevent the "flexing" by keep it more rigid at might RPM.. And because youll be seeing high RPM's its a good rule of thumb to run non self aligning rockers. That would require hardened push rods and guide plates. That way theirs less chance of the pushrod going through your valve cover lol

For springs alot of people suggest the patriot gold extreme's.. myself included, because i too am running them. Along with 7/16" rocker studs.

old93camaro

iTrader: (8)

so what set of springs are you running again and not to be rude but looked like you just opened a catalog and started ordering parts that cost money instead of building something that makes power??? Do you have a tune with this setup

BluelionZ28

Well I have always wanted a car with real horsepower, dad really didnt show me a whole lot and even if i dont know what combinations work I do know how to wrench and want to do it all myself for the most part.

The way the car is right now is the I bought it, about a month after I bought it a valve spring broke which has lead me on this adventure. I am trying to learn more but don't know who the real experts are just yet. But I plan on moving out to Cali and when I get settled in plan on going to school to know what the hell I am talking about.

Oh and the reason that is does sound like a manual is i purchased a Haynes manual as soon as I bought the car and told him to tell me everything he has done to it and i wrote it down in the haynes so i wouldnt forget it.

letsrun97z

iTrader: (7)

If your moving out here plain on making it smog legal

BluelionZ28

Ok Here is what I got to solve my problem for the time being. Hi-Tech™ Race Rocker Studs; 3/8” Stud Diameter, Part # 12495490
Rocker arm kit 1.5 ratio3/8 stud , but wanted Ultra Pro Magnum™: Chevy V8 265-400; 3/8 Stud, 1.52 Ratio.

Ok whatcha think?

BluelionZ28

Oh and i am keeping it registerd in a dif state

jaycenk

iTrader: (1)

Go 1.6 if you can

Low N Slow

iTrader: (4)

If you are buying all new parts why stay with the 3/8 studs and rockers? There was some pretty good explanations a few posts up as to why to go with 7/16 studs.

BluelionZ28

Because right now I hardly have any money to throw around and moving up to the bigger size will cost a little more than i can spend i am getting it drivable and then going to save up for the good stuff.

RamAir95TA

iTrader: (2)

If you can't do it right, don't do it at all. You're buying all new pushrods, studs, and rockers - the 7/16" rockers and studs are the SAME PRICE. The only extra cost is the guideplates, and they're like $40. You'd be foolish to stick with the 3/8", IMO.

BluelionZ28

Correct me if I am wrong but wouldn't going from 3/8 to 7/16 mean that I would have to have the heads tapped, then buy guide plates and roller rockers oh and modify the valve covers or buy new ones. All costs a good amout more than the hardend 3/8 and performance rocker arms.

RamAir95TA

iTrader: (2)

No. The stud threads that engage the heads do not change. The stud itself that the rocker rides on is what is larger. No tapping or drilling necessary.

You do have to buy guide plates, but they're like $40. If you can't afford $40 guideplates which drastically increase high RPM stability, you're in the wrong hobby.

Modifying the valve covers to fit takes all of 10 minutes with a pair of tin snips. Not to mention MOST rockers require trimming of the valve cover supports ANYWAY, regardless of whether they are NSA or SA.

But you've done your homework and made up your mind anyway, so good luck.

BluelionZ28

Now why in the hell hasn't anyone I have been around here where I am said that ****, if its common knowledge its news to me. Great I get so send more parts back lol. Hey I may be a noob to hp and American Muscle but I will never give up what I love doing and thats working on my car always making it better.