TEAM COTTON'S PERFORMANCE TURBO BUICK ONLINE FORUMS  

Go Back   TEAM COTTON'S PERFORMANCE TURBO BUICK ONLINE FORUMS > Technical Forums > Transmissions and Torque Converters

Transmissions and Torque Converters Tranny and torque converter tech support

Reply
 
Thread Tools Display Modes
  #1  
Old 12-05-2008, 01:03 PM
trbochrgd1's Avatar
trbochrgd1 trbochrgd1 is offline
I can't drive 55!
 
Join Date: Nov 2007
Location: North Jersey
Posts: 518
Default RPM Drop and Converter slip%

So I was looking over my files of that 9.56 run. My RPM drop was 400 rpm's between 1-2 (6200-5750) and 550 rpm's 2-3 (6300-5750). Is that around the norm? Or should it be a steeper drop?

Also I plugged all the #'s in on the TCI website and it came up with 6.71% of slip.

6450 rpm's, tire height 29, rear end ratio 3.42, trans ratio 1.1, mph 138.67.

I think that is pretty much right on. For the tire height I even put in 29 to compensate for tire growth. I checked M/T's website for slick growth and they stated @ 150 mph that the tires grow up to an inch to an inch and a half. My slicks are at the end of there cycle so I that's why I plugged in 29.
__________________
87 GN, RPE built 109 stroked, RJC girdle, billet main caps, custom comp roller cam, Champion ported aluminum heads, Champion aluminum intake, T&D 1.65 rockers, 96 lb injectors, Accufab 70mm throttle body RJC pullies, RJC A/C bracket,GTK-850, ATR headers,Deeds electronic boost controller, Cotton’s 4 inch down pipe w/ Turbonetics RG 45 gate, XFI, Cotton’s front mount, Level 10 built 400 trans w/brake, Converter? ,33 spline Moser axles, Spool, HR bar.

New best 9.44 @ 143!
Reply With Quote
  #2  
Old 12-07-2008, 12:50 AM
PaceCarTA's Avatar
PaceCarTA PaceCarTA is offline
Da Big Cheese
 
Join Date: Dec 2007
Location: central NJ
Posts: 50
Default

5750 is your converter , if you were to carry the shift higher it would still drop back to 5750 . with my 3600 AC9" it was at 5500 on the drops
idealy you want the converter to put you into your cams sweet spot ,

6% isnt too bad , ptc converters seems to be tigher than 5%, i was near 20% on the AC
__________________
Paul... NJ rep MAGNABUICK.com
the 86 3450lbs ...1.44 6.19@112 9.72@138 ,
109 234cu stock mains and bolts , irons,
the 87 ttop ,1.37 6.0@ 114 9.45 @ 141.9 25 psi !!
109 235cu .gn1 alum, certified roll cage .
the 87gnx'd FAST B2B TA49 ..back to all stock original #s 109 and trans hipro w stagerite
the 87 GN ttop ..all stock with vac brakes
86 WH1 mini tubbed roll caged 109, extreme 2004r
all on pump 93 and alkycontrol
Reply With Quote
  #3  
Old 12-07-2008, 05:00 PM
trbochrgd1's Avatar
trbochrgd1 trbochrgd1 is offline
I can't drive 55!
 
Join Date: Nov 2007
Location: North Jersey
Posts: 518
Default

Thanks for the reply Paul. I have heard alot of good things about those converters. They seemed to be dialed in for our cars. I have a ton of money into my converter tho. I'd hate to start over again with another brand. It does seem like I am pretty close to being on the money with the Chance converter. Maybe I'll give Marty a call over there on Monday and run the #'s past him and see what he says. If what he tells me, money wise, is more than the PTC converter than I would consider switching.
__________________
87 GN, RPE built 109 stroked, RJC girdle, billet main caps, custom comp roller cam, Champion ported aluminum heads, Champion aluminum intake, T&D 1.65 rockers, 96 lb injectors, Accufab 70mm throttle body RJC pullies, RJC A/C bracket,GTK-850, ATR headers,Deeds electronic boost controller, Cotton’s 4 inch down pipe w/ Turbonetics RG 45 gate, XFI, Cotton’s front mount, Level 10 built 400 trans w/brake, Converter? ,33 spline Moser axles, Spool, HR bar.

New best 9.44 @ 143!
Reply With Quote
  #4  
Old 12-09-2008, 11:03 AM
JCotton1's Avatar
JCotton1 JCotton1 is offline
Married Man
 
Join Date: Nov 2007
Location: Paradise
Posts: 1,434
Default

Quote:
Originally Posted by trbochrgd1 View Post
Thanks for the reply Paul. I have heard alot of good things about those converters. They seemed to be dialed in for our cars. I have a ton of money into my converter tho. I'd hate to start over again with another brand. It does seem like I am pretty close to being on the money with the Chance converter. Maybe I'll give Marty a call over there on Monday and run the #'s past him and see what he says. If what he tells me, money wise, is more than the PTC converter than I would consider switching.
Mike, looks ok for the numbers you ran, the RPM drop was consistent. Considering your shift point was 6200-6300, a 4-500rpm drop for your motor may not be bad. If you consider your motor could be shifted at 6500-6700rpm, your drop would be 7-800rpm, but then when you condider you are only running 22lbs, at 30lbs you may drive through the converter like I did when I turned the boost up 2 weeks ago. I'll be trying one of the PTC converters in my car next time out, maybe next weekend, weather permitting.. but I doubt it. More likely next spring. I'm carrying the PTC converters now, so we'll be working on data with our customers. It looks like the PTC converters are very good converters, but like any converter, sometimes a stall change may be needed. Getting them right the 1st time may not always workout..
__________________
Jack Cotton
Cottons Performance
413-789-0531
Reply With Quote
  #5  
Old 04-30-2010, 07:33 PM
vacuum 6's Avatar
vacuum 6 vacuum 6 is offline
Junior Member
 
Join Date: May 2009
Posts: 24
Default

Quote:
Originally Posted by JCotton1 View Post
I'll be trying one of the PTC converters in my car next time out, maybe next weekend, weather permitting.. but I doubt it. More likely next spring. I'm carrying the PTC converters now, so we'll be working on data with our customers. It looks like the PTC converters are very good converters, but like any converter, sometimes a stall change may be needed. Getting them right the 1st time may not always workout..
How did it work our for ya?
__________________
11.531 @ 122.73 23# of boost & 24°/22° on 93 and alky
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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

Forum Jump


All times are GMT. The time now is 12:12 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.