Bigger Pushrods & Guideplates Legal in Stock now

[Dwight Southerland]

A cheaper alternative for all this would be to go back to old time stocker specs of OEM duration, overlap and valve springs specs. The problem, and thus the explanation, was always that the tech people were not trained well enough to measure all that intricate stuff. Well, I dare say that we have all spent way more money than it would cost to have developed a management, education and certification system for NHRA tech people to do their job. I would easily agree to addition fees for setting records or tear-downs to fund better administration in the tech department for Stock and Super Stock.

[SSDiv6]

Originally Posted by Dwight Southerland

A cheaper alternative for all this would be to go back to old time stocker specs of OEM duration, overlap and valve springs specs. The problem, and thus the explanation, was always that the tech people were not trained well enough to measure all that intricate stuff. Well, I dare say that we have all spent way more money than it would cost to have developed a management, education and certification system for NHRA tech people to do their job. I would easily agree to addition fees for setting records or tear-downs to fund better administration in the tech department for Stock and Super Stock.

I totally agree with Dwight, and it would require a lot of the specs issued by the OEM to be realistic!!! If can recall correctly,I remember the Chrysler 440 and 340 cam specs having something like 240 degrees of overlap and unreal durations specs. The same applied for other makes.

[Jeff Lee]

I totally agree with Dwight, and it would require a lot of the specs issued by the OEM to be realistic!!! If can recall correctly,I remember the Chrysler 440 and 340 cam specs having something like 240 degrees of overlap and unreal durations specs. The same applied for other makes

If you built an engine with the old Pontiac duration numbers (in the area of 324 degrees duration), I doubt you could even get the engine to start!

[SSDiv6]

Originally Posted by Jeff Lee

I totally agree with Dwight, and it would require a lot of the specs issued by the OEM to be realistic!!! If can recall correctly,I remember the Chrysler 440 and 340 cam specs having something like 240 degrees of overlap and unreal durations specs. The same applied for other makes

If you built an engine with the old Pontiac duration numbers (in the area of 324 degrees duration), I doubt you could even get the engine to start!

I agree...like I said, if the old rules are implemented...and enforced properly...there would be a lot of cars out.

[james schaechter]

I think the rule changing should stop during the racing season unless some immediate safety need arises. Think about the HP factor requests. They come in 2 times a year I think. Maybe there should be a specific time for requests and a process that is more transparent to the reps and the racers. It could mean that NHRA tech gets all requests and then the committee should then review then with reps once a year. After all that, the requests along with explainations get posted prior to giving a thumbs up or down. That way there is input from all to help with the committee decision.

The problem with the committee and system now is that it seems that the unintended consequences are not considered.In the current state of the rules, if you are afraid or unwilling to accept breakage, turn the rpm down, lower the pressure, etc. I have also seen many times even on this forum, the racer opinions of slow cars that are just thinking that if only they had this part or that part, then they would move up on the qualifying sheet or perhaps win class. The problem is that they don't often consider that everyone else faster will also benefit from the rule changes.
The rocker arm deal is one I understand, but is still is a limiting factor in engine design and cost. It should have been allowed and the spring pressure could have been limited, but it wasnt' so...We push our stuff as far as we think it will go. If we want to go quicker, we push it a little farther. That increases our risk of breakage. That is a decision each one of us makes and one that each one of us is responsible for. If roller rockers are made legal, It won't be that I just bolt them on, I will order cams and guidelplates and pushrods too. You think that the cam is square now, wait until the rocker arms are legal. The 396 cars will really put the sprng pressure on too.Someone mentioned that then Jesel rocker shafts are next $$$. Many others will push it. I guess the point is that there is no need for a mid season rule change in most cases. Maybe our reps should be part of a redesign of the rule change process. That really is the issue. Some of the committee members in NHRA tech could benefit from modern racer input too. This could be an opportunity to help everyone overall.

BTW, who was pushing for the guideplate pushrod deal? Curious on that one? Jim.

[Dwight Southerland]

Originally Posted by james schaechter

BTW, who was pushing for the guideplate pushrod deal? Curious on that one? Jim.

Whiney butts, that's who. Due to an unwritten policy-procedure that should have been addressed correctly many years ago, the BBC cars can use the Mk VI 9/16" studs and over-the-GM-counter 7/16" pushrods that were developed for the CanAm racers in the 60s and 70s. So, with poor logic as a weapon, the tech department gets assailed with "if they can do it then why shouldn't I be able to" until they cave.

An effective use of the committees would be to only allow rules changes that are authored within the committee (except human safety considerations). Then do everything we can to make the "voter turnout" be a higher statistical number than what happens during elections that determine the future of our nation.

[Jeff Lee]

I wouldn't be opposed to our committee members not only drafting proposals (based on racer requests) but voting on them. Similar to your state legislatures in concept. I think if you vote somebody into office you should suffer or benifit from their position. I personally think throwing everything onto a ballot is rediculous (sp?).

And Dwight, I'm curious as to why GM felt it neccessary to add 9/16" rocker studs on the late model 8.1L BBC. I just can't imagine there was enough strain on the previous design to warrant the engineering and tooling?

[Alan Roehrich]

The 8.1 doesn't really have 9/16" studs. It has a 3/8" stud on the bottom and a shouldered nut that goes through the rocker to create what GM called a "net lash" system, which in plain terms means "non adjustable".

The limit to how "square" a flat tappet cam can be is lifter diameter. A Ford with an 0.875" lifter, a Chrysler with a 0.904" lifter, or an Olds with a 0.921" lifter can generate more tappet velocity (what makes a cam lobe "square") than any Chevy with an 0.842" lifter, regardless of spring pressure. It does not matter how much spring, or how good a rocker you put on it, the lifter diameter is the limit.

I saw 0 HP increase with the bigger stuff on the dyno. If your engine turns above 7500 it might work but did nothing for me. I only see about 6400. I ended up putting back the 5/16 stuff so I could use the factory guide plates.

[james schaechter]

Look, the real issue isn't what is being duscussed now, it is that there is no formal process from NHRA. We don't need any mid year changes for non-safety items period.

Remember when Top Stock took off in IHRA. Those guys were as hard core as it comes and even they got worn out on their own rules changes.

This is not Comp Eliminator. I agree that we have what we have now and going back is not going to happen, but there are too many doors to slip these rule changes under. It appears that there is not careful consideration or control by NHRA.

Any Division reps care to take this on? I think there needs to be a defined process for any rule change proposals. I don't see it now and that is a concern. There are guys boring the cam journals and running roller cam bearings, wait until someone decides we should all have the mopar diameter lifters or who knows what.