Issue: Stock SBC rod reliability; being able to hold forged Speed Pros above 6000 RPM - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 01-15-2006, 07:10 PM
Registered User
 
Join Date: Jan 2006
Location: Orlando, FL
Posts: 21
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Issue: Stock SBC rod reliability; being able to hold forged Speed Pros above 6000 RPM

Hi all:
In short, I'd like to get a notion of how safe I can feel revving stock Chevy rods (180,000 psi bolts) that reciprocate 610 gram forged pistons to above 6000 RPM but not higher than 6500 on occasional basis. This is because of the peak of the power curve occuring around 6 grand (check the link below for the power graph of the setup i'll be using). The heavier forged piston is what raises my concerns, although if I had cast I'd still want to check. The motor is a 355 sbc (400 - 450 hp expected) going into an automatic 1990 camaro which is not a daily driver but will be used on nights/weekends for street fun, occasional track.

I'm looking for input from any experienced person that has ACTUALLY put stock chevy rods through hell or experienced someone do it. In my opinion, you can analyze and make theories all day, but testing proves! I'd like to hear some stories. Have any of you actually experienced a stock rod failure?

I'm already aware that it would be a safer bet to use stronger rods. I'm not trying to be impatient, I'm just so far in the build that it would be very expensive & time consuming to go back, uninstall, buy new rods, rebalance the assembly and reinstall. Of course if it is too risky to use the stock rods, then I must rebuild because then I would waste much more money if the motor blows.

I am building a 355 SBC. Here's some specs:
Reconditioned 350 roller block, 30 over
NEW Scat stock replacement crank
Reconditioned stock rods w/ 180000 psi rod bolts
NEW Speed Pro pistons, forged, mass of 610 grams (heavy which is why i'm worried)
Assembly balanced and dampened w/ fluid filled dampener

Vortec heads (Engine Quest brand) modified for higher lift
Edelbrock 2204 Hyd. Roller Cam
Edelbrock RPM Pro Flo EFI kit #3507 (check it out, very sexy - http://www.edelbrock.com/automotive_...chevy_sb.shtml)
Roller rockers

Since my motor will be very similiar to Edelbrock's 440 HP EFI crate engine, I think it is safe to say that dyno results would be very similiar to Edelbrock's. Check out the power/torque graph for the EFI kit I posted the link for above.

Thanks!

    Advertisement

Last edited by BringBackTheCamaro; 01-16-2006 at 11:35 AM.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 01-15-2006, 07:28 PM
Member
 

Last journal entry: Future Plans
Last photo:
Join Date: Sep 2004
Location: Port alberni, British Columbia
Age: 28
Posts: 118
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Well in my 400 i have stock 350 rods (the heavier duty 70's style) with arp rod bolts and i spun it passed 7k once and 6k a few times and i never had any problems but that was all by accident
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 01-15-2006, 07:33 PM
Registered User
 
Join Date: Jan 2006
Location: Orlando, FL
Posts: 21
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
thanks

ok, good to hear something,
Thanks for replying.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 01-15-2006, 07:34 PM
flaming79's Avatar
Run it if you build it !!
 

Last journal entry: Almost ready to go cruzn
Last photo:
Join Date: Oct 2005
Location: Green River, WY.
Age: 38
Posts: 116
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I had Stock rods in mine and I ran it past 6500 many times. Had it when I was in High School and I rodded the crap out of it,,never had a problem with them.I don't think you have to worry unless your going to exceed 7000 rpms and 500 pounds of torque.Aslong as its been balanced and put together properly.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 01-15-2006, 08:07 PM
lowROLLERchevy's Avatar
... & Insanity Ensues .....
 
Last wiki edit: The FREE T Bucket plans Last photo:
Join Date: Jan 2004
Location: Western NY
Age: 35
Posts: 937
Wiki Edits: 22

Thanks: 0
Thanked 1 Time in 1 Post
a friend of mine from school had a 65 impala, 283 bored to 289, forged pistons (from the swap meet none the less) and the rest was all stock or stock replacement from the local autozone

the bottom end was balanced and assembeled to "reman" quality ... not to much detail, not to sloppy ... just average

now being that hes a georgia boy, and his uncles farm was used for some of the dukes of hazard episodes ....he had the perfect place to practice his back roads driving

that engine was 4 years old by the time i met him, and we put another year of back roading on it during school, and i last talked to him like 3 years after i left, and the engine was still running like it was showroom new

i saw 6 grand at LEAST 3 dozen times on the "straight away" north of laramie .... and way more times then that on the curvy roads .... and twice we accidentaly peged the 8k tach, both times because the 700r4 shifted from 4th to 3rd @120+

if the tack was accurate, the engine hit 10k .... because that needle was WAY past 8 ...

granted its a 289, so theres less piston weight .... and chances are it was one of the rare cases where the engine just for what ever reason just wont come apart ....
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 01-16-2006, 05:28 AM
Hotrodders.com Moderator
 

Last journal entry: PICTURE TEST
Last photo:
Join Date: Jan 2004
Location: york pa
Age: 52
Posts: 2,795
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
rods

The team that i used to build late model engines for had a back-up 358 that turned 4500 off the turns and 7800 plus at the end of the straight-away.. stock rods with arp bolts... zero issues...

Your results may very!!!!!

Keith
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 01-16-2006, 07:39 AM
Mighty Mouse S-10's Avatar
Cleverly disguised as grownup
 

Last journal entry: Hollman & Moody
Last photo:
Join Date: Dec 2004
Location: Huntersville, N.C.
Age: 55
Posts: 140
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Don't cheep out on the rod bolts ( I used the ARP ) and you should be OK.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 01-16-2006, 10:50 AM
johnsongrass1's Avatar
Race it, Don't rice it!
 
Last photo:
Join Date: Jul 2002
Location: Columbia, Mo
Age: 37
Posts: 4,078
Wiki Edits: 0

Thanks: 0
Thanked 9 Times in 9 Posts
I'd be worried about pulling the pin on that grenade your calling a piston.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 01-16-2006, 11:05 AM
NAIRB's Avatar
Hotrodders.com Moderator
 
Last photo:
Join Date: Sep 2002
Location: cimarron, ks
Posts: 1,658
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Stock connecting rods are fine for 6500 RPM. A stock 2 bolt, cast crank, cast pison, stock rod bolt 350 is good for 6500 RPM as far as that goes.

However, there are such things as "cycle life" and "forging flaws", which you cannot detect, so there are those times when things go "bam".

"High performance useage, no warranty, expressed or implied."
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 01-16-2006, 11:06 AM
Registered User
 
Join Date: Jan 2006
Location: Orlando, FL
Posts: 21
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by johnsongrass1
I'd be worried about pulling the pin on that grenade your calling a piston.
heh, bad experiences w/ speed pros? or are you referring to something else?
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 01-16-2006, 11:07 AM
xntrik's Avatar
Save a horse, Ride a Cowboy.
 
Last photo:
Join Date: Jul 2005
Location: Arkansas
Posts: 5,131
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
[QUOTE=lowROLLERchevy]a friend of mine from school had a 65 impala, 283 bored to 289, forged pistons (from the swap meet none the less) and the rest was all stock or stock replacement from the local autozone

we accidentaly peged the 8k tach, both times because the 700r4 shifted from 4th to 3rd @120+

if the tack was accurate, the engine hit 10k .... because that needle was WAY past 8 ...

QUOTE]

Another 1/2 inch of stroke makes a LOT more stress on the rods.

Stock stuff runs fine right up to the instant it blows. Usually unexpectedly, suddenly, and spectacularly.

I'd put a 6000 rpm rev limiter on it...
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
stroke to rod ratio jacobm99 Engine 28 12-16-2013 05:46 PM
383 vs 350 TheCiscoKid Engine 86 05-03-2008 03:10 PM
327 in 88 Truck pete379 Engine 101 01-19-2006 09:03 PM
longest rods in std deck 454 bbc?? deuce_454 Engine 11 01-30-2004 10:06 AM


All times are GMT -6. The time now is 07:25 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.