Roller Cams in Stock Eliminator?

[james schaechter]

Sorry, I took your question literally. I think I understand now.

Originally Posted by GarysZ24

The last time I asked about headers from a place in Arizona, that place was in Kingman, and the guy told me that if I could leave my car with him for 2wks, and pay him $1,000 he could make a set for my car. $1,000???? That's an entry fee for two national events, and two divisionals! I also had this chat back in either 2007, or 2008, thus I'm sure they'd cost even more nowadays. Sorry James, but I can't justify spending that much for headers for a V6, when the "big box store" sells them for less than $300 for a V8! As long as my car is competitive against the index, so I can race with you guys, I'll keep my stock exhaust manifolds, unless or until I get a much better deal for headers. Moreover, I don't have the smarts or the tools (or even the facilities), to make headers myself. I'm .2-.3 under the index for DF/S everywhere I race, and that's plenty good for me. I have no desire to be number one qualifier anywhere I go, and am plenty good with not being one of the bottom three qualifiers either (or in the middle of the pack where those qualifiers have to race against one of the bottom three qualifiers too), since they have to be the first three pair out in first round.

Lol to the "Slacker" comment too Dan...I'd shake your hand for that one!!!!

[Bernie Cunningham]

Dang, Nascar CUP cars, the big boys, have just recently switched to roller cams and lifters, imagine the beatings that the old flat tappet set up took and yet it stayed together.

Yeah, they also dropped the max RPM as well but before that you had an engine running non stop for hours at WOT at around 9K plus RPM. Very impressive indeed.

[Dan Fahey]

Going to Roller Cams.
The racers will have new geometry to play with.
More Spring, Duration and new level of breakage.

Roller Cams will yield higher rpm.
Leading to more and impressive dramatic catastrophic failure!

Need a spring limit rule to back off from limits of material science.

D

[Bernie Cunningham]

Originally Posted by Bernie Cunningham

Dang, Nascar CUP cars, the big boys, have just recently switched to roller cams and lifters, imagine the beatings that the old flat tappet set up took and yet it stayed together for decades.

Yeah, they also dropped the max RPM as well but before that you had an engine running non stop for hours at WOT at around 9K+ RPM. Very impressive indeed.

I would like to bring this back up as it's got to be relevant.
Does anybody know what the, before roller, spring pressures were on a Nascar CUP car?

[Bill Diehl]

Originally Posted by Bernie Cunningham

I would like to bring this back up as it's got to be relevant.
Does anybody know what the, before roller, spring pressures were on a Nascar CUP car?

Its irrelevant....they have 6 and 7mm valve stems in the 60 to 70 gram range with a spintron designed valve train with the proper geometry, they use less spring pressure than you would think.

there is a thought ..lower the pressure so you can spend thousands of dollars on spintron testing.......what a concept

[Rick Leininger Jr.]

Originally Posted by Bernie Cunningham

I would like to bring this back up as it's got to be relevant.
Does anybody know what the, before roller, spring pressures were on a Nascar CUP car?

100 lbs. on the seat, 500 lbs. over the nose, loft enabled valve motion and hp similar to what a roller profile would provide.

Not all the 396 375 guys are blowing up
their stuff. Sounds like the ones that are having problems should go see the engine builders of the ones that are not. Or back
The rpm down below 8300 or whatever they are trying to turn them too. Changing cam profile will help valvetrain failure.

I've heard of places that will run a cam and lifters on a special machine that breaks in the lifters to a new cam. Maybe that's an option, even before you run it in an expensive engine. Just a thought. If the parts are broken in properly the tool steel lifters are supposedly very reliable.

I keep beating a dead horse with this suggestion, but go and test some valvetrain parts on a Spintron.

Instead of lobbying for parts to cover up for a lack of understanding of what is going on in your engines valvetrain wise, try to do some research and talk to people that figure things out.

If you live close to Pa go see Ray and Dave Barton. They have a Spintron machine and have worked on all kinds of engine combos. I'm sure they would be able to fix the problems you are having.

Or

Lane Line, Brian Tilburg, Steve Ficcaci, and Darrel Weikle are some guys that build
Very fast and reliable 396 engines that last and win races. Save your money and go see any of the above people.