[Fot] Racing rod design

[MadMarx]

Hi Bob,

from engineer basis x-beam are the worst you can get. I'll never get a clue how someone could imagine this design.

Cheers
Chris

-----Ursprüngliche Nachricht-----
Von: rkramer3 at austin.rr.com [mailto:rkramer3 at austin.rr.com] 
Gesendet: Dienstag, 21. Juli 2015 21:31
An: 'FOT'; MadMarx
Betreff: Re: [Fot] Racing rod design


Chris,http://webmail.roadrunner.com/do/mail/message/reply?msgId=INBOXDELIM68586&replyAll=on&referrer=msg#

Look at Pauter Rods. they advertise their design as an x-beam. I can't say that they are any better based on long term use but a lot of us switched over due to the increase cost of Carillo's over time.

http://pauter.com/parts/rods/

It just occured to me that you are probably running a custom crank, Chevy rods with custom pistons to match. They may make comparable models to fit that too since I believe that setup was designed around the rods.

http://webmail.roadrunner.com/do/mail/message/reply?msgId=INBOXDELIM68586&replyAll=on&referrer=msg#
Bob Kramer
rkramer3 at austin.rr.com

---- MadMarx <tr4racing at googlemail.com> wrote: 
> Hi Guys,
> 
>  
> 
> After my engine blow at the last race and a rod in two pieces I investigated about rod design.
> 
>  
> 
> In US forums I found an interesting opinion:
> 
>  
> 
> H-beam rods are for low rev high torque engine (turbo, compressor)
> 
> I-beam are for medium torque engines with high revs
> 
>  
> 
> As engineer I agree with this statement. On high revs the rod shaft gets bended back and forth by the inertia caused by the rotation.
> 
> I could imagine that the sharp sides of the H-beam rod will create a crack after a while because the stiffness for bending along the rotation axis smaller than with an I-beam rod.
> 
> That means to me that the fatigue resistance is smaller on an H-beam rod at high revs.
> 
> With high revs on a long stroke engine I mean 6000+.
> 
>  
> 
> The manufacturer of the broken H-beam rod was Scat.
> 
>  
> 
> I think next time I order an I-beam rod from Scat.
> 
>  
> 
> What do you think?
> 
>  
> 
> Cheers
> 
> Chris
>