Re: Lifter rule in Stock
 

This new rule is smart for us Racers that have lost good motors to those JUNK Ceramic Lifters!!!! and for NHRA to check cams.

Re: Lifter rule in Stock
 

Could have a Max Spring Rule instead!
Simpler..
D

Re: Lifter rule in Stock
 

X2 on that Larry!!

By the way, since lift will be checked at zero lash but you wouldn't run a solid at zero lash, I assume you have to give up some lift if you change over.

Re: Lifter rule in Stock
 

Yes, but I don't think you need .006. A lot of older motorcycle exhausts were around .003.
Somebody try and let us know ....

Re: Lifter rule in Stock
 

Please excuse my ignorance. But does this mean we can now run a solid lifter type cam in a hydraulic cam engine. IE a 396 350hp. Or just solid lifters on the hydraulic cam.

Bruce Cameron
1969 Nova E/S
1968 Camaro SS/I

Re: Lifter rule in Stock
 

Since any duration is allowed I don't see why someone couldn't grind slight clearance ramps (just a couple thou) into them, but it doesn't seem worth bothering with.

Re: Lifter rule in Stock
 

If that is the case, then a lot of stockers are about to gain a lot of RPM, and spend a lot of money. This could get really interesting. Or really stupid. Maybe both.

Re: Lifter rule in Stock
 

Alan, that usually goes hand in hand. It's like the chicken and egg thing.

Re: Lifter rule in Stock
 

Mark, this has been done for decades on high perf street engines. ;)

You can be down around .002 (hot) with a solid lifter on a 'hydraulic' cam lobe. Basically, as close to '0' as you can without hanging the valves open. A good rule of thumb.... on a typical iron head/iron block setup, you need around .003 more lash 'cold' than what you want it at 'hot' to allow for expansion. ie: .006 cold will get you .003 hot.

Iron block/alum. heads & alum. block/alum. heads expand differently than iron block/iron head, of course.

Re: Lifter rule in Stock
 

Here we go. Why do the hyd cam combos get an "up grade" and not the solid cam combinations?? IF ( I am not advocating for this) everyone had been up graded to rollers would that not have leveled the playing field? Am I missing something here? Are not the lifter concerns "wiping out a motor" shared with solid and hyd cams?

Re: Lifter rule in Stock
 

Hi Phil.

In a way, a hydraulic cam switched to solids actually loses lift when checked the NHRA way. Since the NHRA checking clearance is .000 (zero), a solid cam loses the lift from the lash when it's running.

A hydraulic lifter is theoretically always at .000 (zero) when it's running.

Re: Lifter rule in Stock
 

So in a sense, all the folks using a hyd lifter, as they were supposed to, can change to solid lifter grind, at the same specs, and gain, what maybe 25 to 30 hp ? Is that idea still correct ?


Im only out of class racing, for a little while...

Re: Lifter rule in Stock
 

Seems like a lot of concern about someone getting an edge by using solids making them faster. If they run heads up, maybe, other than that it's a bracket race. Take away the heads up, run on your number, problem solved with Daddy WarBucks mega dollar engine getting a free ride.

Re: Lifter rule in Stock
 

Good Morning Al.

I understand that. Why the rule change then? Higher RPM capability?

Re: Lifter rule in Stock
 

One less thing for Tech to check, would be my guess?

Re: Lifter rule in Stock
 

My guess would be for ease of tech, the performance
Will change very little , not gonna turn a 6500
Rpm engine into a 8500 or gain a bunch of power.
I would think at very best .03-.05 the current generation
Of limited travel "hydraulic" lifters are solids already!
Just my .02$$ lol!!!!

Re: Lifter rule in Stock
 

Does this mean that Hydrualic rollers can be replaced with Solid Rollers?

Re: Lifter rule in Stock
 

Not sure in the roller stuff, but that is where
You would see the largest gain not flat tappets.

Re: Lifter rule in Stock
 

x2

Re: Lifter rule in Stock
 

Great question!

Re: Lifter rule in Stock
 

I seriously doubt if there is much advantage for people who are maxed out on camshaft technology on their hydraulic lifters. The ramp profiles on those cams are taking assuming that after .015" lifter rise, the lifters are solid anyway. You might be able to speed up the first 6-10 degrees of the ramp a bit with a solid lifter and drop it a bit quicker. One thing for sure, there will be a lot of camshafts sold next year!

Re: Lifter rule in Stock
 

Hi,

I don't see a performance improvement with solid flat tappet lifters to replace hydraulic flat tappet lifters.............

A solid lifter would still have to modified to work with the spring pressures that a run now.....

The ramps are so fast that they almost hit the edge of the lifter now.....

If you ran tool steel, shoeboxes or whatever hydraulic lifters you would still need the same type of treatment or design to make it live......

The main advantages that I can see are a lower price for solids over hydraulics and if you wished, an EDM hole could be used for addition oil supply....

That said.............

How about allowing the front battery in stock to be relocated to the trunk so that you haven't a hot battery lead that is 12' long going from the battery disconnect to the front battery. Even with the disconnect off the 12' long battery cable that is capable of carrying more than 500 amps straight to ground if the cable is damaged is hot...If something bad happened and the fuel system were damaged and leaking the battery and cable are still in the engine compartment and hot..........

Just my thoughts because it would make the cars safer, easier to wire and lighter....

Thanks,
Bob

Re: Lifter rule in Stock
 

I thought a battery disconnect was not necessary for a single front mounted battery?

Re: Lifter rule in Stock
 

NHRA tech department clarifies recent lifter rule change

The change is to allow the use of a solid lifter in place of a hydraulic; you may not replace a flat tappet with a roller.

So what effect if any would there be on a 1993 build chrysler hydraulic lifter on a 383 big block. I assume new valve springs would be needed. Didn't change the rockers, still original as delivered.

Thanks

Eric

Re: Lifter rule in Stock
 

Can't see why new springs would be needed, better have adjustable rockers though. I thinking solids are lighter than hyd. anyway. Also a lot cheaper.

Re: Lifter rule in Stock
 

I am glad I run Pure Stock!
Old Stock without any of today's issues!:D
D

Re: Lifter rule in Stock
 

No, not for a single front. But with a front mounted and a rear mounted batteries, the disconnect has to kill a running engine.

Re: Lifter rule in Stock
 

Probably 95% of hydraulic cam stockers have solid lifters already and have had for many years,they just have .015'' travel in the pushrod seat and are considered hydraulic by the rules,it is a solid lifter with the pushrod seat cut for .015'' travel,nothing hydraulic about it and .010-.012'' of that travel is taken out when the valve is set depending on lash the lifter is compressing .003-.005'' the only difference is the lash is between the pushrod seat and lifter body rather than between the cam and lifter.
This rule doesn't change the need for ceramic,tool steel or whatever kind of special lifter is being used,it doesn't change the cam profiles they are already solid lifter profiles.
Only thing it changes is a hyd. roller that has a true hyd. roller lifter which has probably been modified to only have .015'' travel will now be able to take them out and replace with a much lighter solid roller lifter,which won't make any difference because they are already running a spring strong enough to handle the extra lifter weight,so maybe they get a few more runs out of their springs.
Nothing to get excited about.
Mike Taylor 3601

Re: Lifter rule in Stock
 

I wire a car the "correct" way so there is no "hot wire" from front to back when the switch is off in the back with a front-mounted battery also. PITA, a lot of extra time and $$$, but it is legal, it works, and kills the engine when the switch is pushed in.

Re: Lifter rule in Stock
 

I agree ^^
All my cars with rear mounted batteries are wired this way. That big fat welding cable running up the side of car is only hot when the starter is kicking over.

Years ago I wired a rear mounted battery the way NHRA shows and that fat wire shorted out and caught on fire. Bad idea.

Ever since then I have wired it this way in the diagram... the correct and safest way...( note that the switch still kills every functioning item on the car when switched off )

http://i148.photobucket.com/albums/s...ocation3-1.jpg

Re: Lifter rule in Stock
 

Looking at this diagram it's the way I have wired mine. But it still has a constant hot wire running to the alternator. Could you run this wire to the main switch and then to the battery ?? And if so how big of a switch (amp wise) should we use?

Re: Lifter rule in Stock
 

Only if you run it to the source side of the switch.

If you kill the main switch, you kill engine power.
You kill engine power, you kill the alt.

If I wire the alt. to the switched side of the main ( that feeds the fuse box), the engine will still run if the main disconnect is off because the alt. is still feeding 12v to the fuse box while the engine is still running.


Thus the location of the alt. wire on the source side of the main switch, not the fuse box side.


edit: Sorry Jeff if I de-railed your thread

Re: Lifter rule in Stock
 

Exactly, and well said Mike!!!

Re: Lifter rule in Stock
 

I might be looking at the diagram wrong but it looks like the battery is not killed by the switch, hot wire still on post along with the ground??
The alt and big red wire to sol. would have to be on the other side of main switch to completely shut off current from the bat, pourpse of main disconnect. That alt wire is still hot according to that drawing.

Re: Lifter rule in Stock
 

I've been trying to figure out for years why NHRA requires the master switch to be on the positive cable. It should be on the negative cable. It would be much safer and easier. No battery ground and everything will be killed. Somebody please explain to me why I'm wrong.

Re: Lifter rule in Stock
 

Hi
If there is an accident and the positive and negative crushed would still have a short and you have not addressed the issue of protecting both the front and rear batteries............
If wanted you could control the front battery with a constant duty rely.......
Sorry I hijacked thisthread....

Bob

Re: Lifter rule in Stock
 

That is correct Bob. For safety reasons I don't think a front and rear battery should be allowed. Also why is a cut off switch only required for rear mounted batteries?

Re: Lifter rule in Stock
 

Hi,

They should allow a maximum of 2 batteries and allow them to be located in the trunk for safety reasons, much the same that was done to allow..............

Front disc brakes......
Aluminum seats..........
Roller rocker arms....
Solid rear axles in IRS cars.......
Aftermarket rods, pistons and valve train.....
Full cages that extend through the firewall.........
I am still trying to figure out the safety advantage of an aluminum radiator...

I could go on and on about the STOCK rule changes for safety, but I will stop now..........

Bob

Re: Lifter rule in Stock
 

Sorry on hijacking this thread but when did NHRA allow aluminum radiators as replacement? I have been out of racing for a while!

Re: Lifter rule in Stock
 

The Safety people at the track would know that all door cars have their battterys in the back and controlled by the master cutoff switch.