Is a 3-step bad?

[JP1738]

I've used a 3-step in my Super Street car and now my stocker since I started racing. I'm not necessarily reliant on it, but I like having it to keep me from zinging the motor in the water box. I feel confident after this many years racing I don't need one, but again, it's just there in case it tries to get away from me.

Something I've noticed over the years: I frag valve train components once a year. Every year, without fail, I will break a rocker stand, rocker arm, or push-rod. Sometimes all three depending on what gives up first. I've never had a catastrophic failure, just something that puts a cylinder down and ruins my race day. And every single time this has happened (I think 5 times now) it happened during the burnout early on in the race. Usually first or second time run of the race, it will frag something in the valve train and that's my day, over. Is the three-step causing this? I'm not exactly beating the 3-step up, honestly. It might nick it a touch while holding the line lock, but it's not hammering it the whole time. Or is it just a coincidence? If I remember correctly, it rarely frags mid-burnout on the three step, normally its just after I release the Line Lock and begin to pull out of the burnout when RPMs may climb higher than the 3-step and get close to the high side.

For reference, my high-side is usually set around 7500 and my 3-step is 6500 with a converter flash of 6000.

[Steve Stasko]

I don't think this is the place to admit to using a three-step in a Stocker...but if you're breaking valvetrain parts in the other car...it's not from the three step. You've got some unhappy geometry or your maintenance intervals need changed.

[JP1738]

Originally Posted by Steve Stasko

I don't think this is the place to admit to using a three-step in a Stocker...but if you're breaking valvetrain parts in the other car...it's not from the three step. You've got some unhappy geometry or your maintenance intervals need changed.

I have a 3-step on my stocker but it's set way low, around 5200. I was warned to keep rpms down during the burnout as free revving my 305 near 7000 could frag a stock rocker arm or send a push rod through it. It is in an abundance of caution, not necessarily inexperience.

As for my other car, I lash valves every oil change (40-50 runs) but rarely see much change. I might have one or two that need adjusted but typically even when I check them, they were ok anyway. I would be surprised if it was a geometry issue, Scott Duggins at PAR put it together for me and has freshened it multiple times in the last 5 years. I trust his engine building prowess. I should note that I get these rocker stud breakages despite running a stud girdle.

Is a three step bad/illegal in a stocker? Or just frowned upon? Honestly don't know, I'm still new here.

[Lenny5160_v2]

I don't use a burnout limiter in my dragster anymore. Never have in the door car.

Not sure if that is causing your issues, but there seems to be enough info out there about limiters not being great for valve train health.

[JP1738]

Originally Posted by Lenny5160_v2

I don't use a burnout limiter in my dragster anymore. Never have in the door car.

Not sure if that is causing your issues, but there seems to be enough info out there about limiters not being great for valve train health.

That's what I'm getting at here. I like having it, but if it's gonna keep breaking stuff, I'm not sure I need it enough to justify it.

[Steve Stasko]

Originally Posted by JP1738

Is a three step bad/illegal in a stocker? Or just frowned upon? Honestly don't know, I'm still new here.

I've always taken the rulebook for it's literal value. It says two-steps are permitted, but there is no verbage on three-steps...which I've always assumed to mean they are not permitted.

If you're constantly going out and banging the limiter, then yeah, it's going to break stuff. The only time I ever put my car on the limiter is on the launch. I still believe something else is going on though with the valvetrain.

[MR DERBY CITY]

I use a limiter in the water for protection . I have never had an issue in over 30 years . On the other hand Buddy Morrison swears that they are NOT a good idea to use in the water…..I have a feeling that your limiter is wired in with the line loc …That is a VERY bad idea …. When you release the line loc button you have no protection coming out of the water …..perhaps this is when you damage your parts ????

[pmrphil]

I'd mention to Scott about breaking studs when still using a girdle - something is NOT correct. I have only seen that happen when using an incorrect (wrong) girdle for the stud spacing or, as was said, a geometry issue. Scott's a smart guy, give him a yell. Tell him I said "Hi".

[JP1738]

Originally Posted by pmrphil

I'd mention to Scott about breaking studs when still using a girdle - something is NOT correct. I have only seen that happen when using an incorrect (wrong) girdle for the stud spacing or, as was said, a geometry issue. Scott's a smart guy, give him a yell. Tell him I said "Hi".

He's well aware of the issue, I show up at his shop to buy whatever needs replacing when it happens. He has said I should really consider going to a shaft rocker as the hp I'm making and rpms I turn are not really friendly to a conventional headed 383 with Brodix Trac 1 heads. I think I'm going to save that money for now and spend it when I can get my hands on a decent set of 18 degree stuff. I'd like to go full shaft at that point.

[dragracerray]

Originally Posted by JP1738

If I remember correctly, it rarely frags mid-burnout on the three step, normally its just after I release the Line Lock and begin to pull out of the burnout when RPMs may climb higher than the 3-step and get close to the high side.

For reference, my high-side is usually set around 7500 and my 3-step is 6500 with a converter flash of 6000.

JP1738,
If you are talking about hitting 7500 in the burnout with a Stocker I would say you are over revving. I would question why you want to go that high in the burnout,. I have a 6000 limit in the burnout for my Stocker. It is on a toggle switch so that even when I release the LineLoc the rev limiter is still active. Finish burnout and flip toggle switch to race mode. Ray