Mild SBC 383 help. - Hot Rod Forum : Hotrodders Bulletin Board -- 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
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 01-23-2013, 11:18 PM
Join Date: Nov 2001
Posts: 447
Wiki Edits: 0

Thanks: 0
Thanked 11 Times in 10 Posts
Mild SBC 383 help.

Anyone out there have a desktop dyno to run my new build combo?. This is an inexpensive SBC short rod 383 that a built but have not yet put in a vehicle. I built it out of parts I had on the shelf in the shop. It's a 350 4 bolt roller block .030 overbore, One Peice rear seal. (think it was from a boat). New ext balance Eagle 3.75 stroke crank, SBC 400 balancer, SBC 400 5.56 rods, Mahle brand hyperutectic short skirt (so they clear the crank counterweights) flat top 1.56 comp hgt pistons. Cam is reground marine hyd roller vortec, 428 lift, 196 dur and it appears to have a 109 LSA, Heads are 062 vortecs, chambers are 62 CC, pushrod holes enlarged, screw in studs and guideplates, new springs with steel retainers designed to take 490 lift, 1.5 rockers. Dual plane low rise vortec carb intake with holley #3310 750-CFM carb, Stock HEI with bronze dist gear. Felpro composite head gasket. I am concerned about the compression ratio, appears it would be over 11:1 area and the cam may be too small, I really want a torque monster for occasional street use with a few trips to the drag strip. it has a turbo 350 with 3800 stall converter and rear end is a ford 9 inch, 4.86 gears. Again this was assembled from parts laying around in the shop for years and I don't have a ton of money in it, (however the machine shop charged me more to balance it than I paid for the crank and pistons, ouch). Can anyone run this on a desktop dyno for me and have any constructive advice?. I imagine it would have good torque but severe detonation with pump gas. Thanks in advance for any help.


Last edited by Studebaker; 01-23-2013 at 11:43 PM.
Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 01-23-2013, 11:43 PM
techinspector1's Avatar
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Zephyrhills, Florida, USA
Age: 75
Posts: 15,448
Wiki Edits: 326

Thanks: 1,544
Thanked 2,073 Times in 1,602 Posts
Yeah, that's what I see too, 11:1 with iron heads.
76cc heads would bring it down to around 9.7:1, which I would still consider too high to build a plain old street torque motor.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 01-24-2013, 07:41 AM
vinniekq2's Avatar
Registered User
Join Date: Jun 2012
Location: BC,Canada
Age: 59
Posts: 11,637
Wiki Edits: 0

Thanks: 693
Thanked 1,340 Times in 1,243 Posts
4.86 gears will limit your top speed to just over 90 mph.Dont waste your time going to the drag strip unless its 1/8 mile.After you fix the CR I see over 360 horses.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


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
Mild 383 SBC - Critique, Please. Painstain Hotrodding Basics 10 04-15-2011 06:21 AM
Stock TPI system on mild 383 Drewnashty Engine 38 03-12-2008 01:25 PM
Mild 350 SBC buildup 79 Malibu327 Engine 6 09-21-2004 08:56 PM
question about this TPI on a mild 383 solowookie Engine 7 12-02-2002 08:18 PM
TPI on a mild 383??? solowookie Engine 3 11-26-2002 06:37 AM

All times are GMT -6. The time now is 08:43 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.