Notices
Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by: KPower

Why you dont cheap out on rods on a rebuild.

Thread Tools
 
Search this Thread
 
Old Oct 24, 2009 | 01:59 PM
  #1  
y8s's Avatar
y8s
Thread Starter
DEI liberal femininity
iTrader: (8)
 
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Default Why you dont cheap out on rods on a rebuild.

So I was tearing down the spare 2001 motor I have in my shed today... (got it from fmowry who purchased the car from Robbi Laurenson who ran a haltech and water injection and maybe around 250 rwhp if I recall all that correctly) and pulling out the pistons to send across the pond and found this:








Yes that's right folks! FOUR BENT RODS. Not sure if this matters, but 1 and 4 were bent in the plane of the rod and 2 and 3 were bent out of plane.

I think the motor had less than 650,000 miles on it at this point. frank can pipe up on that though. Everything else looks great. No serious wear on any parts or surfaces.

go figure.

go get rods for your build for $300.
Old Oct 24, 2009 | 02:04 PM
  #2  
hustler's Avatar
Tour de Franzia
iTrader: (6)
 
Joined: Jun 2006
Posts: 29,085
Total Cats: 375
From: Republic of Dallas
Default

bmw:
Old Oct 24, 2009 | 02:04 PM
  #3  
hustler's Avatar
Tour de Franzia
iTrader: (6)
 
Joined: Jun 2006
Posts: 29,085
Total Cats: 375
From: Republic of Dallas
Default

yeap...aside from the block, our little motors are **** in comparison to just about any other 4-cylinder.
Old Oct 24, 2009 | 04:11 PM
  #4  
Full_Tilt_Boogie's Avatar
Elite Member
iTrader: (1)
 
Joined: May 2009
Posts: 5,155
Total Cats: 409
From: Jacksonville, FL
Default

Originally Posted by hustler
yeap...aside from the block, our little motors are **** in comparison to just about any other 4-cylinder.
I wouldnt say any other 4-cylinder, but most any modern 4-cylinder, yes...

B18C5 FTMFW!
Old Oct 24, 2009 | 04:17 PM
  #5  
tyson87's Avatar
Senior Member
iTrader: (6)
 
Joined: Aug 2008
Posts: 1,020
Total Cats: 1
From: West Palm Beach, FL
Default

Originally Posted by Full_Tilt_Boogie
I wouldnt say any other 4-cylinder, but most any modern 4-cylinder, yes...

B18C5 FTMFW!
my buddy is parting his out right now. u need rods or pistons?
Old Oct 24, 2009 | 04:24 PM
  #6  
JasonC SBB's Avatar
Elite Member
 
Joined: Jul 2005
Posts: 6,420
Total Cats: 84
Default

Would a motor run seemingly normally with rods like that ???
Old Oct 24, 2009 | 05:28 PM
  #7  
y8s's Avatar
y8s
Thread Starter
DEI liberal femininity
iTrader: (8)
 
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Default

I bet neither owner of the car had any clue that there was something wrong. There's really no way to know that the rods look like that until you tear it down.

a bent rod that's only marginally shorter will hardly show up on a compression test...
Old Oct 24, 2009 | 05:40 PM
  #8  
kotomile's Avatar
Elite Member
iTrader: (24)
 
Joined: Oct 2006
Posts: 7,537
Total Cats: 42
From: Monterey, CA
Default

Daaaamn, they did that with 250 hp?

Gulp.
Old Oct 24, 2009 | 05:43 PM
  #9  
tyson87's Avatar
Senior Member
iTrader: (6)
 
Joined: Aug 2008
Posts: 1,020
Total Cats: 1
From: West Palm Beach, FL
Default

i dont think its a matter of whp, isn't det. what kills rods?
Old Oct 24, 2009 | 05:44 PM
  #10  
Toddcod's Avatar
Elite Member
iTrader: (8)
 
Joined: Oct 2007
Posts: 1,829
Total Cats: 0
From: Dallas
Default

Originally Posted by hustler
yeap...aside from the block, our little motors are **** in comparison to just about any other 4-cylinder.
I can't agree with that. I think the 1.6L is one of the best motors ever made. And so did few magazines for a while.

I buy nothing but 90-93 to turbo. Bone stock motors, as old as they are. I never work on them. They Run great and hold up well to boost. psi for psi, I would tear up the honda's.

Yea the new motors are startig to carry more power. But will they have the legacy that these have had. I doubt it.

For the dated technology on these motors, they still hold their own. And if clean, N/A and under 190,000 miles are usually still very dependable.
Old Oct 24, 2009 | 05:44 PM
  #11  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,541
Total Cats: 4,364
From: Chantilly, VA
Default

Originally Posted by tyson87
i dont think its a matter of whp, isn't det. what kills rods?
torque pushes down on the pistons, too much and they squish the rods.
Old Oct 24, 2009 | 06:07 PM
  #12  
y8s's Avatar
y8s
Thread Starter
DEI liberal femininity
iTrader: (8)
 
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Default

Originally Posted by tyson87
i dont think its a matter of whp, isn't det. what kills rods?
that's just it, the pistons look pristine



There's no broken lands or pitting or any obvious signs of repeat offending detonation. plus as I mentioned, there was a water injection system hooked up.

I think the rods were just designed for no boost.
Old Oct 24, 2009 | 06:15 PM
  #13  
tyson87's Avatar
Senior Member
iTrader: (6)
 
Joined: Aug 2008
Posts: 1,020
Total Cats: 1
From: West Palm Beach, FL
Default

with the rods bent did it F up the cyl walls?
Old Oct 24, 2009 | 06:16 PM
  #14  
ZX-Tex's Avatar
Elite Member
iTrader: (15)
 
Joined: Dec 2007
Posts: 4,847
Total Cats: 27
From: San Antonio, Texas
Default

Bent two (killed one) of the four stock rods in my stock engine last year (as some of you may remember). Everyone was quick to blame detonation, but I do not think that is what did it. I think it was 16 psi with a GT2560 on a cold morning

Too much power = too much cylinder pressure = too much compression load on the stock rods = Euler column bucking (a.k.a. bent rods).

225 < Too much power < 300 WHP (based on anecdotal evidence, assuming stock redline).
Old Oct 24, 2009 | 06:17 PM
  #15  
kotomile's Avatar
Elite Member
iTrader: (24)
 
Joined: Oct 2006
Posts: 7,537
Total Cats: 42
From: Monterey, CA
Default

Look at the positive side, it was a DIY variable-compression engine!
Old Oct 24, 2009 | 07:45 PM
  #16  
rrjwilson's Avatar
Junior Member
 
Joined: Aug 2008
Posts: 390
Total Cats: 1
Default

Originally Posted by kotomile
Look at the positive side, it was a DIY variable-compression engine!
Differential compression surely
Old Oct 25, 2009 | 12:11 AM
  #17  
NoMiEzMX-5's Avatar
Junior Member
 
Joined: Oct 2008
Posts: 88
Total Cats: 0
Default

The award for the best 4 banger has to go to the mighty 4G63..hands down..
Old Oct 25, 2009 | 12:18 AM
  #18  
kotomile's Avatar
Elite Member
iTrader: (24)
 
Joined: Oct 2006
Posts: 7,537
Total Cats: 42
From: Monterey, CA
Default

Best 4-banger?



Billet block, 55 psi, 4,000hp. I win.

Norwood Racing's 4,000 hp Max-4 Integra - Tech Review - Turbo Magazine
Old Oct 25, 2009 | 12:32 AM
  #19  
magnamx-5's Avatar
:(
iTrader: (7)
 
Joined: Jul 2006
Posts: 8,255
Total Cats: 4
From: nowhere
Default

yeah this is all the more reason for me to put in my mtuned rods that ive had for th epast 2 yrs almost and nvr installed.
Old Oct 25, 2009 | 12:58 AM
  #20  
NA6C-Guy's Avatar
Elite Member
iTrader: (1)
 
Joined: Feb 2008
Posts: 7,930
Total Cats: 44
From: Birmingham Alabama
Default

More the reason I have completely decided against any boost on my stock rods. My $1000 and 3 month long rebuild was completely useless because I cheaped on the rods. Go me!



All times are GMT -4. The time now is 02:27 AM.