Which TBI for vortec-head 383 in '89 c1500 - 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 06-21-2010, 12:01 PM
Registered User
 
Join Date: Nov 2009
Location: Brandon FL
Age: 56
Posts: 12
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Which TBI for vortec-head 383 in '89 c1500

Hey guys I need more pointers. I'm preparing to replace my old tired 305 with a vortec-headed 383 I just finished building. Although I'll start with a quadrajet I already have, my guess is that I'll eventually want a 454 TBI to feed the 383. Assuming I get the 454 TBI and 454 injectors, what other different parts will I need to get?
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 06-23-2010, 05:41 PM
355iroc's Avatar
Registered User
 
Join Date: Jun 2010
Location: sc
Posts: 5
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
tbi sucks leave the carb on
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 06-23-2010, 06:28 PM
Registered User
 
Last photo:
Join Date: Apr 2007
Location: Seattle, Wa
Posts: 6,438
Wiki Edits: 0

Thanks: 3
Thanked 331 Times in 288 Posts
Quote:
Originally Posted by darefugee
Hey guys I need more pointers. I'm preparing to replace my old tired 305 with a vortec-headed 383 I just finished building. Although I'll start with a quadrajet I already have, my guess is that I'll eventually want a 454 TBI to feed the 383. Assuming I get the 454 TBI and 454 injectors, what other different parts will I need to get?
The computer chip needs to know what size engine and injectors are under the TBI. Injectors are limited by duty cycle (time on as a percent of total time) which is about 80% max otherwise they overheat. The factory is usually very conservative with this, so 350 injectors can be stretched to feed a 383 but not a 454. 454 injectors would have excess flow capacity so when mounted on a 383 they wouldn't be on much at all, though TBI cycles twice per crank revolution but it's on time against off time we're measuring for injectors of differing volumetric capacities.

The cam comes into play, but with TBI cam's over 215 degrees of duration get to be a sensor sensitivity problem as the manifold vacuum falls with a bigger cam. So you end up with big flow changes for smaller and smaller vacuum changes till the sensors just can't discriminate the subtle vacuum changes that result in big mixture changes any more.

You will need a custom chip in the computer, check out these places that specialize in them.

http://www.fastchip.com/

http://www.tbichips.com/

http://www.hypertech-inc.com/

Bogie
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
Vortec TBI & Head CC's DScott9160 Engine 1 10-10-2003 11:20 PM
need help to turn a 350 tbi into a rollerized 383 tbi Bradless Engine 2 01-03-2003 10:13 PM
383 tbi 85 regal Engine 0 12-11-2002 03:33 PM
89 Chevy P.U. TBI ????? catdad2u Engine 1 11-12-2002 02:52 PM
85 chevy 305 heads on an 89 TBI chevy 350? jazzguitar Engine 4 11-03-2002 04:11 AM


All times are GMT -6. The time now is 10:25 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.