For those engineer minded folks who know of critcal loads on pistons.
Renault has said their F1 V10 this year is seeing 8500g's acceleration force on a piston at max RPM
A number of years ago I was working on V12 designs (for myself -fictious engine) @ 3.5l and I was getting a figure of 7000g @ 14797rpm and I couldn't find away for it to stay together. I would bounce this info across a F1 engine designer then at Honda and he assured me that he was seeing these figures and alittle beyond, but no one else said it could survive a lap much less 2 hours of abuse.
Just for comparison:
A 350 cheby (opps Chevy) 483hp @ 6149rpm is seeing 4350g's force.

I have no access to programs anymore, anyone with access it would be great to know what the 5.4 mod motor is seeing at different rpm's.
anyone???

 

Sounds very interesting! I'd like to know as well....

And I'm sure those who are contemplating staying with our stock pistons and just upgrading the rods would also be interested in this sort of information...

 

See if this helps

http://www.ncs-stl.com/Files/PstnVel.xls

 

Thanks awhittle
I've got to be missing something. @ 5500rpm our pistons are only seeing 1448g
6.657 rod
4.157 stroke

OK after digging I found my engine design program. One problem, it's in 5 1/4" floppy disc.







Now that you've stopped laughing..........








Now.............











Ok thats enough. I know they went out with Saturday Night Fever, but that is what it's on. Anyway to still use it?? Or is it FUBAR?

 

Get a 5.25" floppy drive and try... Wonder if windows will laugh at you for trying to use one.

 

Interesting info.........

--Joe

 

Nope, a 350 Chevy regardless of horsepower @ 6149 rpm sees an average of 1502 g's force.

 

According to my old software which was/is very reliable, according to a highly respected F1 engine designer who said my #'s were very close the #'s I generated were accurate. So I'm going with experience and saying 4350 would be a very close #.



Anyone have a 5 1/4" drive?

 

OK here is the 350 cheby info

 

I updated My sheet

http://www.ncs-stl.com/Files/PstnVel.xls

AW

 

Your calculating tension at TDC? Which is a % of max critcal, which I may never know .

I hate using my brain it hurts. There that'll fix it. The cause of the worlds problems and the solution.

 

Thanks awhittle

You be one smart cookie

So, since I'm at work until late late late today I would have to guesstimate our figures at:
2762 g's at 5500rpm and Max critical load of ~4932g's
2581 g's at 5800rpm and Max critical load of ~4608g's
2321 g's at 5500rpm and Max critical load of ~4144g's
2237 g's at 5400rpm and Max critical load of ~3994g's
2155 g's at 5300rpm and Max critical load of ~3848g's
2114 g's at 5250rpm and Max critcal load of ~3775g's

Shifting below 5400 seems like a pretty good idea huh?
If you daily drive it. If you don't...............?

 

Bleh...

Anyone else feel really dumb besides me? :o

-Mike

 

Redneck Ferrari should. He's ignoring common sense in favor of an incorrect understanding of a so-called "expert" - a computer program.

Redneck, if you look at the sheet you posted, you can even SEE that it says I'm right:

"STANDARD FOR CRITICAL LOADS: 4350g's"

That is the standard. That is not what a 350 generates.

"TENSION AT TDC: 2440 g's"
"COMPRESSION AT BDC: 1299g's"

That's what the engine is actually doing. Even the simple average, not the mean, is at about 1800g's, which is very close to my 16xx number.

If you have any more questions just ask.

 

Those F1 motors are amazing. 17K+ RPM.