C-6 torque converter problem? - 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> Transmission - Rearend
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 12-15-2010, 01:05 PM
Registered User
 
Last photo:
Join Date: Jan 2010
Location: Buffalo
Posts: 221
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
C-6 torque converter problem?

Hi i have an 86 fullsize bronco with a rebuilt 351w engine. performer manifold, 600cfm edelbrock carb, comp xtreme 4x4 cam (1,000-5,000rpm) headman elite headers and true dual 2 1/2" exhaust. I advanced the timing until the starter started kicking back, then i backed it off just enough where it would start normally. Truck has 33x9.50 tires with 4.11 gears and stock/rv converter. The problem that i'm having is the truck has zero power. The truck is horrendous, literally. I know its a big heavy truck, but my 100% stock 90,000 mile automatic civic absolutely destroys it in acceleration. There has to be something wrong somewhere, it starts fine, idles smooth. So while trying to figure out the problem i remembered installing the torque converter without filling it with fluid, would this maybe damage the converter and be a possible cause for my problem? Trans shifts fine and doesn't shutter, fluid is bright red. Engine was put together by a reputable shop who knew the engine would be in a truck, so i don't think they put the cam in retarded? Im confused? would the torque converter be a possible culprit? Thanks.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 12-15-2010, 01:41 PM
Mertz's Avatar
Member
 
Join Date: Jun 2002
Location: Reardan, WA
Posts: 665
Wiki Edits: 0

Thanks: 1
Thanked 3 Times in 3 Posts
Been there done that. Going to smaller tires will help. If your tires are bigger than stock it will change the rear gear ratio.

Check this site out
http://www.wallaceracing.com/gearcalc1.php

And this
http://www.wallaceracing.com/gearcalc1.php

http://www.f-body.org/gears/

You also need to check the stall on your converter.

I have two threads on here now that deal with this subject.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 12-15-2010, 02:14 PM
Registered User
 
Last photo:
Join Date: Jan 2010
Location: Buffalo
Posts: 221
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks for the reply Mertz, i understand about the gears. The stock gears were 3.50 with 29" tall tires, when i had the engine and trans rebuilt i switched to the 4.11 gears to compensate for the larger tires. I would like to keep the 4.11's if i could to keep my rpms down on the highway, that is why i didn't go with 4.56's. With the 4.11 and 33" tires my effective gear ratio is 3.61. So with the engine rebuilt with cam, headers, manifold, four barrell i would think it should be able to get out of its own way. I mean this truck moved around better stock. Still confused.

Last edited by turchiac; 12-15-2010 at 02:21 PM. Reason: Forgot to add info
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 12-15-2010, 04:33 PM
Mertz's Avatar
Member
 
Join Date: Jun 2002
Location: Reardan, WA
Posts: 665
Wiki Edits: 0

Thanks: 1
Thanked 3 Times in 3 Posts
I am out of my element here but I think you also need to match the cam to the converter. If the cam makes power at very high rpms and the converter stall is low there would be a problem.

I will watch this thread and see what the experts have to say. Keep us informed if you figure this out.

I would think that with my exceptionally tuned 350 with 4.10 gears I would burn rubber anytime I want but it just doesn't. I am going to smaller tires in the rear and see what happens. I have an 1800 stall.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 12-15-2010, 05:07 PM
Registered User
 
Last photo:
Join Date: Jan 2010
Location: Buffalo
Posts: 221
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
The cam is a comp X4250H 4x4 cam, duration @50 is 206/214 advertised duration of 250/258 valve lift 448/483 lobe separation is 111. I figured i could use a rv converter with this, i wonder if a slight stall might help? but it is a pretty small cam.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 02-09-2011, 02:34 PM
Registered User
 
Last photo:
Join Date: Jan 2010
Location: Buffalo
Posts: 221
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I recently had the gears swapped to 5.14 in the rear and 5.13 in the front. This helped somewhat but the truck still seems to lugg around. Would a 2,500 stall be too much for this setup? Truck is used only in winter to go to work (about 6 miles each way) so deep snow is the terrain it will see mostly, no rock climbing or trails. The current converter is an RV unit seems to stall around 1300rpm. Thanks
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 02-09-2011, 04:27 PM
tnsmith10's Avatar
when will it rain???
 
Last photo:
Join Date: Jul 2003
Location: where its very dry and dusty
Age: 43
Posts: 1,297
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
if the cam you have is rated from 1000-5000 rpm, the problem is not the converter, as a stock stall c-6 converter is roughly around 1400 rpm as it is.
as far as the engine is concerned, is this the origional engine thats been rebuilt? or a whole different engine?
what the compression ratio of the engine?
as far as the converter not being prefilled, its not necassary to prefill the converter as its the 1st thing that gets fluid once the engine is running. c-6 converters, even though they do fail, they rarely do.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 02-09-2011, 04:37 PM
Registered User
 
Last photo:
Join Date: Jan 2010
Location: Buffalo
Posts: 221
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Engine was the original motor, 351w HO originally rated at 210hp 305 ft lbs, it has 8:5 compression. Runs smooth and starts right up. Just feels really weak, especially with the steep gears.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 02-09-2011, 08:49 PM
Registered User
 
Join Date: Jan 2005
Location: Brookfield, WI
Age: 53
Posts: 499
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Your converter is too tight. Get a street/strip or street stall converter so that you can let the engine breathe.
Check it out this way: Get the truck up to or over 40 MPH. Mash the accelerator to the floor. You must get kickdown or the test will fail. Assuming kickdown, if the truck jets and moves like you expected, your converter is too tight for the cam. With 5.14s in the truck the engine should be well past the converter stall effective range.
If it doesn't go like a scared dog, you have engine problems.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 02-09-2011, 09:25 PM
Registered User
 
Last photo:
Join Date: Jan 2010
Location: Buffalo
Posts: 221
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
With the 5.14 when the truck is moving along at 30-40mph and i kick it down, it moves pretty good. Its when i hit it from a dead stop that it doesn't feel strong or when using normal part throttle acceleration, this is when it seems as though i have to push the pedal harder than needed to get the truck moving. TCI recommended there breakaway converter 441001. I already have a trans cooler, would this help that much with initial take off and part throttle acceleration?
Reply With Quote Quick reply to this message

Recent Transmission - Rearend 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
Torque converter problem??? blacklabzeke Transmission - Rearend 2 12-31-2008 03:55 PM
Help tuning 383 for street use strokey Engine 34 04-11-2008 05:51 PM
Torque Converter Question newbielike Transmission - Rearend 2 12-17-2007 05:53 PM
torque converter IDENTIFICATION 327amc Transmission - Rearend 5 03-26-2005 06:23 PM
Is my jeg's brand torque converter a dud? elukas Transmission - Rearend 5 10-07-2004 11:08 AM


All times are GMT -6. The time now is 05:35 PM.


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.