External Balance - Team Camaro Tech
Engine General Engine Discussion.

 
LinkBack Thread Tools Display Modes
post #1 of 11 (permalink) Old Oct 22nd, 14, 12:51 PM Thread Starter
Gold Lifetime Member
Jon
 
Join Date: Jul 2005
Location: IN
Posts: 283
External Balance

I am looking at purchasing a crate 450hp 383. It uses an externally balanced crank, in a late model roller block. Builder says that I will need to purchase a 400 balancer and a late model 350 wighted flywheel. Should I be concerned about the balance tolerance of purchasing these parts? If I go with name brand stuff, will the balance be good enough for a 5500 rpm street engine? I understand it's best to balance the internals with the flywheel & balancer, but that's not possible with a crate motor.

Jon
JD4020 is offline  
Sponsored Links
Advertisement
 
post #2 of 11 (permalink) Old Oct 22nd, 14, 01:10 PM
Senior Tech
Al
 
Join Date: Nov 2002
Location: Vancouver, USA
Posts: 10,511
Re: External Balance

Pretty sure the factory roller blocks used a 1 piece rear main seal, although there is a kit that will allow you to install a 2 piece RMS. The flyheels/flexplates will not interchange between the two - different bolt circles. Make certain you know what you're getting. There are scads of ext balanced 383s running around. I'd have felt more comfortable had the machinist had these parts in hand when the engine was built/balanced.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
BPOS is offline  
post #3 of 11 (permalink) Old Oct 22nd, 14, 01:47 PM
Senior Tech
Wes
 
Join Date: Dec 2003
Location: Leander, TX
Posts: 2,762
Re: External Balance

Agree with BPOS,..doesn't make sense.

If you're not running her often on the dark side of 6000 RPM (you said 5500 would be tops), here's the crank you need:

http://www.summitracing.com/parts/sca-935050l

...this is:

* for 5.7" rod,
* 3.75" stroke
* one-piece rear main (for your roller-block),
* 350 mains,
* internal balance (uses neutrally balanced flywheel and balancer)
* Scat's "cast steel" 9000 series
* 51 lbs,
* $243 with free shipping (can't beat it)

Internal balancing is the way to go.

Good luck!
Straight-line-69 is offline  
 
post #4 of 11 (permalink) Old Oct 22nd, 14, 02:39 PM
Senior Tech
Brandon
 
Join Date: Apr 2009
Location: DFW/LBC
Posts: 213
Re: External Balance

All 1pc seal blocks stock were ext balance rear/internal balance front cranks. Most Scat/Eagle kits come this way, I use hundreds of them a year and there is not a problem with them.

If he is using a ext balance front & rear setup, that's just a cheaper budget kit that only Eagle does, maybe a few other sub par companies. It would be ok for what you are doing.

71 Chevelle 496 Stroker Hyd Roller 675HP, TH400 3500 Stall, 3.73 12 Bolt.

ATK HP ENGINES

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Custom Built Street-Strip-Racing Engines
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Notalent is offline  
post #5 of 11 (permalink) Old Oct 22nd, 14, 02:42 PM Thread Starter
Gold Lifetime Member
Jon
 
Join Date: Jul 2005
Location: IN
Posts: 283
Re: External Balance

I am considering a Blueprint 383. They specify an 8" 400 balancer and a late model 350 flywheel will be required. My concern is how well balanced it will be with aftermarket parts, not used during balancing. I know they build a lot of these, so maybe it should not be a concern.
JD4020 is offline  
post #6 of 11 (permalink) Old Oct 22nd, 14, 03:09 PM
Senior Tech
Brandon
 
Join Date: Apr 2009
Location: DFW/LBC
Posts: 213
Re: External Balance

Quote:
Originally Posted by JD4020 View Post
I am considering a Blueprint 383. They specify an 8" 400 balancer and a late model 350 flywheel will be required. My concern is how well balanced it will be with aftermarket parts, not used during balancing. I know they build a lot of these, so maybe it should not be a concern.
No comment on there stuff...Just do a search.

71 Chevelle 496 Stroker Hyd Roller 675HP, TH400 3500 Stall, 3.73 12 Bolt.

ATK HP ENGINES

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Custom Built Street-Strip-Racing Engines
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Notalent is offline  
post #7 of 11 (permalink) Old Oct 22nd, 14, 03:17 PM Thread Starter
Gold Lifetime Member
Jon
 
Join Date: Jul 2005
Location: IN
Posts: 283
Yeah, I'm not looking for comments regarding Blueprint itself. I've already searched plenty. I'm really just looking for comments regarding the balancing. Thanks.
JD4020 is offline  
post #8 of 11 (permalink) Old Oct 22nd, 14, 03:35 PM
Gold Lifetime Member
Don
 
Join Date: Jan 2005
Location: 2 Dog Town in West Texas
Posts: 11,154
Re: External Balance

Quote:
Originally Posted by JD4020 View Post
I am considering a Blueprint 383. They specify an 8" 400 balancer and a late model 350 flywheel will be required. My concern is how well balanced it will be with aftermarket parts, not used during balancing. I know they build a lot of these, so maybe it should not be a concern.
From Blueprint engines, request a bob weight card if possible.

As for the balancer and flywheel, purchase good stuff, not the china brand.

Sounds like you already purchased this motor? I would get it running asap as I have heard of many complaints that were let go and the warranty went out.

Even better, round up the parts you need and take them to a shop that does engine balancing. That way you know what is happening.

As for the 9000 series cast crank, I have heard good stuff behind it. Its not a forged crank but it will be good for under 7k rpm.
You need to mock this stuff up before you go the balance shop. Make sure your piston bottom balance pads clear the crank throw.
Remember, the 400 balancer is what keeps this motor in balance.
What was said about the flywheel interchange is correct. Late model one piece cranks and early model cranks hubs have a different id.

As mentioned , do a search on the company, issues are out there on this site.
https://www.camaros.net/forums/showthread.php?t=191597

Don
TC # 349
Zdld17:69 Z/RS,306, NOR141111, 9N554XXX, 12A, X3G, 59/59,723, AFR 195,CCC282/290HR, TKO 600, BU1122B1E Owner since Dec 1968

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
zdld17 is offline  
post #9 of 11 (permalink) Old Oct 22nd, 14, 04:08 PM Thread Starter
Gold Lifetime Member
Jon
 
Join Date: Jul 2005
Location: IN
Posts: 283
Thanks for the info. No, I haven't purchased yet, just trying to get in front of any issues, or talk myself out of it. I've researched a lot, and feel comfortable with BP, in general.
I've got a 509 2 bolt 400 ready to be built, but all the shops I've taken it to, want $6500+ to build me a 450/450 engine. Kind of hard to justify the $$ for a weekend cruiser, when I can by a BP crate for $3700.
JD4020 is offline  
post #10 of 11 (permalink) Old Oct 22nd, 14, 04:49 PM
Gold Lifetime Member
Fred
 
Join Date: Nov 2006
Location: Seabeck WA
Posts: 8,375
Re: External Balance

Quote:
Originally Posted by JD4020 View Post
Thanks for the info. No, I haven't purchased yet, just trying to get in front of any issues, or talk myself out of it. I've researched a lot, and feel comfortable with BP, in general.
I've got a 509 2 bolt 400 ready to be built, but all the shops I've taken it to, want $6500+ to build me a 450/450 engine. Kind of hard to justify the $$ for a weekend cruiser, when I can by a BP crate for $3700.
Doesn't that raise a red flag with you? Are you asking us to tell you that your rationalization is OK?

One owner 69 Camaro,(yep, bought it new
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
)
RS SS Hugger Orange, L88, 4:10's tru-tack posi, ducted hood, Endura, spoilers.
TH400 (CX) with Coan 8" converter, GV-OD, 8 track still on console and best et 10.495,
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
128.79mph 1.428 60'
All with 1960's stuff. (except tires and converter)
+ MT Super Scavenger headers & 3" full exhaust with X pipe. 3700 lbs. with me in it.
1000cfm AED and HD Harold-Lunati SR, 725 lift with shaft rockers too.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Fred Ficarra is offline  
post #11 of 11 (permalink) Old Oct 22nd, 14, 04:57 PM
Gold Lifetime Member
Don
 
Join Date: Jan 2005
Location: 2 Dog Town in West Texas
Posts: 11,154
Re: External Balance

Quote:
Originally Posted by JD4020 View Post
Thanks for the info. No, I haven't purchased yet, just trying to get in front of any issues, or talk myself out of it. I've researched a lot, and feel comfortable with BP, in general.
I've got a 509 2 bolt 400 ready to be built, but all the shops I've taken it to, want $6500+ to build me a 450/450 engine. Kind of hard to justify the $$ for a weekend cruiser, when I can by a BP crate for $3700.
Consider a crate motor with a factory warranty, for a few $$ more. Takes all the worry and guess work out of the picture.
https://sdparts.com/details/gm-perfo...parts/12498772

I think $6500 for a cast motor is too high, I built my own 383 with forged parts for under 6k. Course I spec'd the motor to what I wanted to do, Cruise long distances.

Don
TC # 349
Zdld17:69 Z/RS,306, NOR141111, 9N554XXX, 12A, X3G, 59/59,723, AFR 195,CCC282/290HR, TKO 600, BU1122B1E Owner since Dec 1968

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
zdld17 is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
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.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.



Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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

 
For the best viewing experience please update your browser to Google Chrome