Boost it,

It's stuff that is totally unrelated to anything being discussed. Rick has an LT1 car that went 8.30s at 168-170 the first time he went down the track and then the next morning at Thunder the turbo was destroyed during that night? It has nothing to do with your question or anything though at all. It will go much faster when it hits the track again after PRI probably 7s. It's all LT1 stuff so it is also a stock block.

I was sure someone sent you a spreadsheet of the formulas though for finding instantaneous and peak piston speed and piston acceleration and if not I can if you would like one. The ACCELERATION of the piston is the key to the stress not it's velocity or piston speed. The formula for FORCE is F=MA so if you know the mass of the parts being accelerated you can find the forces that muct be acting on them. The rpm you are at affects the acceleration (and thus forces) of the piston as a square where as piston speed from more stroke at the same rpm is a linear increase.

Then there's the fact that most engines peter out in rpm due to the heads and valvetrain which is what really sets the upper limit on piston speed and rpm in the first place not bottom end components. Of course these bottom end components must be strong enough to take the accelerations that the final engine build dishes out to them. It's very hard to do that AND lighten everything up a lot over what is already being used with the lower rpm stuff already. Another words I can get just as light a piston for a 410 chevy as a 310 chevy. We all know which one makes much more power.

 

I agree. A good big one will beat a good little one every time!

Rich

 

please send

 

Boost it,

Will send it to you from home!

 

That applies in other areas also. To quote an OLD line from my youth, "That's what she said."

 

Damn guys..... felt like I just read a book. Feel like you just wrote one?

There always has been and always will be debates regarding engine design and what works best. The good point of all this is they keep getting better each year.

Thanks for all you're insights. You guys really should get together if you're all at a certain event. Probably enjoy it more than you realize.

 

its from my youth...and in still in it :skep:

 

OldSStroker,

Well asking all my crazy sources I get 240-270G for Aluminum F1 pistons and 215-245g for Aluminum MMC pistons so far. They have lighter versions too as does everyone in real racing but they are not run in the actual race engines but rather like a test or an older qualifying engine or on the two teams that are 100 HP down like the AsiaTech. Still that is CRAZY light. I know who makes the pistons in MMC for most of the teams including BMW. All that I know of still only run 4 valves though. I've seen lots of the 5 valve stuff but I guess it doesn't make the power at this time.

The F1 engineers are MUCH more concerned about the bottom end life in terms of RPM though rather than piston speed asking two so far as they also noted that the old "stroker" F1 engines used in some popular endurance racers usually turn as high a piston speed while lasting even 12 and 24 hour races at the lower rpms and larger strokes that they run these engines at. Some of them also have made close to the same power even with restrictors in them but at larger sizes!

Speaking of all this crazy F1 stuff were you at PRI? Did you see any of the trick bearings speaking of friction reduction at 20,000 rpm?

 

You also saw the AisaTech (1999) pistons/crank/rods also at PRI, I assume. 233 gms for one style of piston. Yeah, 4 valves and the valve reliefs are most of the combustion chambers. Mahle had some interesting stuff to say about F1 pistons, also. Unfortunately not much about current stuff. "We'd have to shoot you..." They suggested that today's F1 piston are NOT heavier than the '99 AsiaTech ones.

I believe ProStock has a piston weight rule if about 460 gms. That's about 100 gms more than pre-rule pistons according to some of the piston guys. 360 gms for a 4.6+inch bore pumping out 175+ hp/hole is pretty good. If piston weight is somewhat proportional to bore size ^2, and F1 engines have 3.8 to 3.9 bores, the math is interesting when you compare F1 and ProStock pistons.

Cosworth (Jag?) F1 engine was interesting also, as is the tech book on 2000 Ferrari F1. These had variable length inlet trumpets which cycled length as many as four times from 11000 to 18000 rev range.

I agree that piston speed isn't too much of a factor mainly because they (F1)are keeping it below 5000 fpm, which is lower than Cup. I doubt that they would increase it 15% if they were looking for 15% more rpm, however. I think we will see F1 engines continue to spin faster, and have larger bore/stroke ratios which are 2.3+ now in F1, but only 1.3 or so in Cup. With the Cup "gear rules" for 2005, we may not see much more rpm there.

Bearing speeds are very high on F1 engines compared to Cup. With rod journals around 1.45(F1) vs 1.85(Cup) and twice the revs that's got to be a challenge.

 

I know many pro stockers and with the exception of maybe GA no one I know has ever seen PS pistons that light! I can find out but I know the aluminum berylium MMC stuff for PS was almost that light and that is now banned in PS too. Apparently the Berylium and fiber based MMCs were almost unbelievable though in lightness and overall strength.

Those F1 bearings cost over 35,000 dollars an engine!

 

Any theories why Anderson has been cleaning up in Pro Stock?

 

He has it all together. If anyone knew exactly why then they would be as fast too! I know the NASCAR connection there didn't hurt Greg. Those guys see stuff all the time that they can't use but that a drag racer could due to the endurance requirements that the NASCAR stuff must meet compared to Pro-Stock. He has a great team and the cars, engines and drivers are all doing a great job. Grumpy was doing good there too for a while. It also has a great deal to do with the teams resources and budgets. WJ has been running the DRCE3 so that is where he has been this year.

 

How about any specifics as to what Anderson is doing different mechanically from the others. Perhaps he's running a small bore, long stroke?

 

Funny I picked up 2 360g Pro Stock Pistons at the CP booth. 4.600" Bore, around 1.000" Compression Height, kind of thought they were PS pistons and CP reaffirmed that. They are old news now since they can't even run them that light anymore because of the rules.

Also confirmed that Al F1 pistons from the 16,500rpm AsiaTech motor were 230-236g's by two different compaines. Guessing is good but when you see the parts in person it's much better.

Oh and asking the right cam people how fast could I turn a 358 cube motor with a pushrod, rocker arm setup like oh say a Cup motor the response I got was "You could go 11,000 if you wanted too, I can make the valvetrain turn as fast as you want it too. More RPM is just going to cut down on the aggressiveness." I would say he probably knows a few more people working on valvetrains in Cup than anyone you know, so it's a pretty good source.

Interesting show indeed.

Bret

 

The Asiatech was the weakest thing out there in F1. It was for sale to anyone. With less power and RPM you can lighten anything up. You are not seeing anything that really runs in F1 at PRI. The Vendor that really sells more F1 pistons wasn't far away and it wasn't CP either. They just made those rods and you could see how big the bolts were! For such light parts and moderate piston speed. I wonder if RPM had anything to do with that instead?

Those super light CP pistons won't make any power in a PS motor either. Anyone can lighten up a piston by machining it down on the bottom to a very low thickness but that doesn't mean that is what they really run. CP has not sold any 360g pistons to anyone I know in PS including the ones that are winning and that's from the guys that really build them everyday Bret. They are much heavier. I don't even know of anyone running CP in PS in fact.

I already told you that they can turn more rpm and you could too by laming out the valvetrain but you will lose horsepower and airflow that way. When you are racing you are trying to MAKE, not LOSE horsepower. The piston speed and this RPM where they make power is due to their valvetrain and heads. A stock valvetrain can turn 11,000 with a stiff spring and a .200 lift cam. Does that mean anything really?

NO.