Go Back  R/C Tech Forums > General Forums > Nitro On-Road
 AFTER MARKET RODS FOR 12s anybody??? >

AFTER MARKET RODS FOR 12s anybody???

Community
Wiki Posts
Search

AFTER MARKET RODS FOR 12s anybody???

Thread Tools
 
Search this Thread
 
Old 04-25-2003, 12:33 PM
  #16  
Tech Apprentice
 
Join Date: Jan 2002
Location: Beyond Circle Talk
Posts: 80
Default

o

Last edited by DanielSon; 04-09-2007 at 06:06 PM.
DanielSon is offline  
Old 04-25-2003, 12:44 PM
  #17  
Tech Elite
 
Corse-R's Avatar
 
Join Date: Aug 2001
Location: Madrid (Spain)
Posts: 2,121
Default

Originally posted by DanielSon
Con-rods fail. They are designed that on purpose, They gotta make money somehow. You only speak of basic alloys that are well known to the public, there are way better alloys that are not widely used that exceed 7075 and other aluminum based alloys, and what condition of 7075 do you speak of?
Danielson:

I not negate that conrods fail, but there's a such high probability that you should change it due to bushing wear than a snapped unit. Engine manufacturers refrain on putting weak elements on their engines, are the faulty use that makes it break (heard some quite big freerevs on the boxes and on my internals said, blow it please, blow it please) some people thinks that doing such manouvers will show how 'powerful' and how noisy are their engines.

Changed my last conrod on an engine with more than 7 gallons thru it (a Sirio .21 AAC) who uses a 'weak conrod' said by some people who broke one.

Well, if you plan to dig on 'exotic Aluminium alloys' like 7450 and such similar, go yourself and put a quote for a billet/rod of those type of alloys (probably they force you to order a minimum weight and probably excessive for you.

The problem with blowing conrods is fixed putting a larger 2nd gear that lowers a little the rpms as told time ago popsracer not a harder conrod that probably break the crank nipple.
Corse-R is offline  
Old 04-25-2003, 01:02 PM
  #18  
Tech Apprentice
 
Join Date: Jan 2002
Location: Beyond Circle Talk
Posts: 80
Default

.

Last edited by DanielSon; 04-09-2007 at 06:06 PM.
DanielSon is offline  
Old 04-25-2003, 01:17 PM
  #19  
Tech Regular
iTrader: (2)
 
Jonathan's Avatar
 
Join Date: Jan 2002
Posts: 262
Trader Rating: 2 (100%+)
Default

Corse-R

Quit being a condescending know it all man! You are making yourself look silly. BTW... I don't think anyone is really impressed by your credentials....except yourself.

Pops.. you're right about gearing up to preserve a rod, but the downside of course is losing some aceleration. What's more important...I guess....or built a stronger rod.
Jonathan is offline  
Old 04-25-2003, 02:59 PM
  #20  
Tech Fanatic
Thread Starter
iTrader: (6)
 
kickass's Avatar
 
Join Date: May 2002
Location: Sydney
Posts: 785
Trader Rating: 6 (100%+)
Default

corse-r RELAX this thread was created to spread knowledge and to provide people with another option.
As far as gearing is concerned ive been racing for over 12 years have won 5 Australian titles, am a team sponsored driver.
7 of those twelve years have been at the same track, what im trying to say is that we think we have worked out what gearing to run but thanks all the same.
I dont know if its in your nature but try to be constructive not destructive oterwise theres plenty of other threads out there.

Danielson thanks for your reply, i am very interested, i will PM you my email, if you can email me some details thanks.

PS im off to another major meeting interstate, so ill be off air for a couple of days cheers.
kickass is offline  
Old 04-25-2003, 03:03 PM
  #21  
Tech Apprentice
 
Join Date: Jan 2002
Location: Beyond Circle Talk
Posts: 80
Default

taco bell

Last edited by DanielSon; 04-09-2007 at 06:07 PM.
DanielSon is offline  
Old 04-25-2003, 03:45 PM
  #22  
Tech Elite
iTrader: (2)
 
Francis M.'s Avatar
 
Join Date: Apr 2002
Location: Yorba Linda, CA
Posts: 4,723
Trader Rating: 2 (100%+)
Default

most rod failure is when the brass bushing
wears out. The problem with using a harder
material for the bushing would be wearing
out the crank pin. if you are snapping rods
then maybe the ti rods would be a good
idea, from my own experience most of my
rods wear out from the bushing. I usually
change the rod once after that you might
want to check out the tolarance on the
crank pin also.
Francis M. is offline  
Old 04-25-2003, 03:48 PM
  #23  
Tech Apprentice
 
Join Date: Jan 2002
Location: Beyond Circle Talk
Posts: 80
Default

soft taco no cheese

Last edited by DanielSon; 04-14-2007 at 11:14 AM.
DanielSon is offline  
Old 04-25-2003, 04:22 PM
  #24  
Tech Elite
 
AMGRacer's Avatar
 
Join Date: Oct 2001
Location: Brisbane, Australia
Posts: 3,939
Default

9/10 rod failures (excepting the picco ones) are due to the brass bushing not getting enough oil or the brass bushing to pin gap becoming too large.

Titanium rods will not prevent the bushing detonating and showering your piston/sleeve with brass shards. Also most titanium will stretch more than aluminium under higher loads reducing head/piston crown clearance.

To answer the question from kickass I have tested a MT12 aftermarket rod from Carlsen Tuning and it was great. However I have never done a rod in a Nova anyways.
AMGRacer is offline  
Old 04-25-2003, 05:45 PM
  #25  
Tech Regular
 
rrgt_kid's Avatar
 
Join Date: Apr 2003
Location: Brisbane Australia
Posts: 310
Default

with novarossi 12 engiens the conrod it self doesnt stretch at all its only the bushing that lets go. 21 size engiens are a different story thought but if a 12 size if racing once a fortnight the rod should be replaced once every 6 months or before a major race event!
if your local hobby shops tell you it should be replaced every couple of race meets ,that bull and they want to make money out of you all, unless if you abuse the motor!

ive never ever done a rod but ive worn out a jp crank on the big end journal.

jeremy
rrgt_kid is offline  
Old 04-25-2003, 07:53 PM
  #26  
Tech Champion
 
Manticore's Avatar
 
Join Date: Aug 2001
Location: Heaven
Posts: 9,999
Default

Ti rod? i wanna laugh !! it if does "work", it only degrade the performance of your engine. what is the density of Ti alloy compare to Al alloy? Not to mentioned about the heat characteristic of Ti. If Ti is the right material, you would not be the first person to name it for this purpose. Brass is used for the bushing because brass is soft enough to protect the crank pin from wearing. high grade brass is expensive. do you really understand engine design?

many ideas were bought up such as ball race bushing but the engine manfactorers always go back to alloy rod with brass bushing. Piston ring design but no one use it now. boost bottle and who wants it anymore? Those are "constructive" but not practical. Race engine is high wear engine.

I remember there are aftermarket rods from paris racing as well as Asso R&D (long times ago) and they do use alloy rod with brass busing but with beefed design.
Manticore is offline  
Old 04-25-2003, 09:05 PM
  #27  
Tech Elite
 
AMGRacer's Avatar
 
Join Date: Oct 2001
Location: Brisbane, Australia
Posts: 3,939
Default

Originally posted by rrgt_kid
with novarossi 12 engiens the conrod it self doesnt stretch at all its only the bushing that lets go.

jeremy
Trust me the do stretch if you rev them hard enough.
AMGRacer is offline  
Old 04-25-2003, 09:15 PM
  #28  
Tech Regular
 
Old Skool's Avatar
 
Join Date: Nov 2001
Location: SF Bay Area
Posts: 342
Default

Who said that the rod end itself doesn't go?
Attached Thumbnails  AFTER MARKET RODS FOR 12s anybody???-dsc01542.jpg  
Old Skool is offline  
Old 04-25-2003, 09:24 PM
  #29  
Tech Elite
 
AMGRacer's Avatar
 
Join Date: Oct 2001
Location: Brisbane, Australia
Posts: 3,939
Default

Originally posted by Old Skool
Who said that the rod end itself doesn't go?
Thats the exception to the rule for sure. I assume you had a runaway?
AMGRacer is offline  
Old 04-25-2003, 09:50 PM
  #30  
Tech Regular
 
rrgt_kid's Avatar
 
Join Date: Apr 2003
Location: Brisbane Australia
Posts: 310
Default

well that pic doesent look like you ran your motor at normal temp and under normal running coditions. or it was a runaway! by the way is that from a 3.5 motor???

jeremy
rrgt_kid is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.