Drag Racing Tech
Sponsored by:
Sponsored by:

Optimal Converter Stall Speed / Shift Ext.

Thread Tools
 
Search this Thread
 
Old 09-06-2009, 09:01 PM
  #1  
TECH Fanatic
Thread Starter
iTrader: (2)
 
stumprrp's Avatar
 
Join Date: Aug 2007
Location: Rhode Island
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts

Default Optimal Converter Stall Speed / Shift Ext.

Hey guys,

Im just wondering what my optimal converter stall speed would be given my cam specs and the power it made on the dyno and where. I feel that the 3600 is too small and my shift extension is too great. The car shifts at around 6500 and drops to 5100.

Let me make this clear, i dont care about drivability, i care about performance and that only. So what is the best number for a shift extension? 600-800 RPM?

My car made its peak torque at 5000 RPM and peak horsepower at 6300 RPM.

Once again, from a race car stand point, not a street car.
Old 09-07-2009, 11:16 AM
  #2  
TECH Fanatic
Thread Starter
iTrader: (2)
 
stumprrp's Avatar
 
Join Date: Aug 2007
Location: Rhode Island
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts

Default

anyone? i also would like it to flash higher then it does off the line, which is only like 33-3400
Old 09-07-2009, 04:49 PM
  #3  
Launching!
iTrader: (20)
 
night ryder's Avatar
 
Join Date: Apr 2007
Location: south dakota
Posts: 276
Likes: 0
Received 0 Likes on 0 Posts
Default

my cam peaks at 6500. i have a ati 8" 4900 stall, but i also have a th400.
Old 09-07-2009, 05:04 PM
  #4  
TECH Addict
iTrader: (2)
 
JUICED96Z's Avatar
 
Join Date: Jul 2002
Location: Indy
Posts: 2,970
Likes: 0
Received 1 Like on 1 Post

Default

My last car had a 10 inch 4000 stall, cam peaked at like 6800 or 7,000, shift light pill was a 7,000, shifted then, car flashed to about 4,000. The 4000 was for streetability (I did not build the car). Your 3600 is way to small.

I had a TH-400 and 4.10's with a 28 inch tall tire....... I can't remember RPM drop.... going into second I was doing 75mph on 7 cylinders so I did not need many gear's...

Cam was like a 276/650 in a 468 BBC....... With a few things changed I think it would have loved a 5000 stall or so.

Send the stall in and have it taken up to a 4,000 and see how you like like..... if you had more gear that would help I think. For all out performance you cam is less then great if you ask me.

I would get a different cam and match the new stall speed to that cam and get whatever gears it says to run..... also depends on compression. My cam wanted at least 12.1 and the car had 10.5
Old 09-07-2009, 07:13 PM
  #5  
TECH Fanatic
Thread Starter
iTrader: (2)
 
stumprrp's Avatar
 
Join Date: Aug 2007
Location: Rhode Island
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts

Default

i understand for "all out" my cam isnt great, but its enough for a stock 103k mile LS1 with stock heads. i rather just get a proper stall to go with my cam if you know what i mean, money is tough.
Old 09-07-2009, 07:59 PM
  #6  
TECH Addict
iTrader: (2)
 
JUICED96Z's Avatar
 
Join Date: Jul 2002
Location: Indy
Posts: 2,970
Likes: 0
Received 1 Like on 1 Post

Default

Then I would get it stalled to what the cam company recomends..

It will run a lot better I bet once you do that.

A local has a 403 with a cam that is close to a T-Rex, I don't THINK the heads are ported, FAST 92 intake and he just ran 10.9 with a 4000 stall, 10 bolt with 3.42's and N/A to give you an idea...

Here is his info

LS2 403 Stroker in it with a 4l60e, Yank ss4000 stall and 3.42's (in the stock 10 bolt.) 10.993 @ 125.61 mph, 60' was a 1.659
Old 09-07-2009, 08:23 PM
  #7  
11 Second Club
iTrader: (1)
 
ABA383's Avatar
 
Join Date: Jun 2006
Location: Southern PA
Posts: 1,507
Likes: 0
Received 7 Likes on 4 Posts

Default

The folks at PI (Vigilante) generally recommend the stall speed to be 500-900 rpm below the torque peak for a street/strip set up n/a...As yours is more race car I'd say a Vig 4400 would work very well...

--Alan
Old 09-07-2009, 08:25 PM
  #8  
11 Second Club
iTrader: (12)
 
01FbTaWs6's Avatar
 
Join Date: May 2005
Location: Cedar Rapids, IA
Posts: 1,142
Likes: 0
Received 0 Likes on 0 Posts

Default

you need to give FTI a call. Your going to pay for it, but you wont get a better converter. Ide say you need atleast a 4400 stall. The cam peaks pretty high. Give FTI a call and talk to Greg. Give him your setup and he will hook you up with the perfect stall. Wont find any better
Old 09-07-2009, 09:36 PM
  #9  
TECH Fanatic
Thread Starter
iTrader: (2)
 
stumprrp's Avatar
 
Join Date: Aug 2007
Location: Rhode Island
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts

Default

thanks for the help guys, Slowhawk reccomended at least a 4000, 4400 for the best results. i think if i can have someone help me take my converter out ill send it for a restall.

i hear vig's are very underrated, my buddy has a 4200 but it flashes to 4800 or so.
Old 09-08-2009, 08:50 AM
  #10  
LS1Tech Co-Founder
iTrader: (34)
 
Pro Stock John's Avatar
 
Join Date: Nov 2001
Location: Chicago, IL
Posts: 44,653
Received 1,099 Likes on 721 Posts

Default

I'd go 4400 for NA. I'd go 4800-5000 it was me.

I'm up in the air on the motor side of my new (to me) 2000 Z/28, if I got NA only I'll go 4800-5000 stall.
Old 09-08-2009, 09:24 AM
  #11  
TECH Fanatic
Thread Starter
iTrader: (2)
 
stumprrp's Avatar
 
Join Date: Aug 2007
Location: Rhode Island
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts

Default

what are the plans for your car john? 5000 is serious
Old 09-08-2009, 01:05 PM
  #12  
TECH Addict
iTrader: (2)
 
JUICED96Z's Avatar
 
Join Date: Jul 2002
Location: Indy
Posts: 2,970
Likes: 0
Received 1 Like on 1 Post

Default

Originally Posted by 01FbTaWs6
you need to give FTI a call. Your going to pay for it, but you wont get a better converter. Ide say you need atleast a 4400 stall. The cam peaks pretty high. Give FTI a call and talk to Greg. Give him your setup and he will hook you up with the perfect stall. Wont find any better
Never heard of them???

90% of the people out there will tell you the best out there are Neil Chance and ATI. I don't think he need's one of them honestly... at least not one of their top of the line stall's..

Originally Posted by Pro Stock John
I'd go 4400 for NA. I'd go 4800-5000 it was me.

I'm up in the air on the motor side of my new (to me) 2000 Z/28, if I got NA only I'll go 4800-5000 stall.
Good point on the N/A, my last car had a 300 shot on it.


With the mods he has though I think a 4000-4400 would be about right.... 4800-5000 I think would be a little much. It is pretty much a moderate cam only car. I would think he would need more gear and cam to really make a 5000 work.... just my opinion...
Old 09-08-2009, 01:18 PM
  #13  
9 Second Club
iTrader: (5)
 
ATVracr's Avatar
 
Join Date: Mar 2004
Location: GB
Posts: 5,297
Received 1 Like on 1 Post

Default

Glide should fall back 1200rpm.... TH400-350 1,000rpm
that will get you in the ball park.

That is different than flash rpm(stall), both can be changed/adjusted by converter makers.
Old 09-08-2009, 01:31 PM
  #14  
LS1Tech Co-Founder
iTrader: (34)
 
Pro Stock John's Avatar
 
Join Date: Nov 2001
Location: Chicago, IL
Posts: 44,653
Received 1,099 Likes on 721 Posts

Default

What does your dyno graph look like? Other factors to consider include how much power you make at a given rpm.

I'm not 100% decided on the combo in front of the firewall, what you like to see me do?
Old 09-08-2009, 01:55 PM
  #15  
TECH Fanatic
Thread Starter
iTrader: (2)
 
stumprrp's Avatar
 
Join Date: Aug 2007
Location: Rhode Island
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts

Default

something nasty thats for sure!

the graph is relitively flat, but the good stuff doesnt come on after 5000 RPM, which is my peak torque, i mean, flooring the car from a dead stop you can actually feel the cam "kick in" also look for a video of my cars 11.96 run, you can hear it there too.
Old 09-08-2009, 02:24 PM
  #16  
LS1Tech Co-Founder
iTrader: (34)
 
Pro Stock John's Avatar
 
Join Date: Nov 2001
Location: Chicago, IL
Posts: 44,653
Received 1,099 Likes on 721 Posts

Default

What is your raceweight?
Rear tire size?
Post your best time slip...

If you shift at 6500 you don't want to go lower than 4500 stall for the quickest ET, that's a given. But you need to hook a big stall too.
Old 09-08-2009, 07:18 PM
  #17  
TECH Fanatic
Thread Starter
iTrader: (2)
 
stumprrp's Avatar
 
Join Date: Aug 2007
Location: Rhode Island
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts

Default

race weight is 3430 with me in it but i hope to get it to around 3350
tire size is 26 inch
best time was a 1.69 60 foot, 7.61 at 91 mph in the eigth, and 11.90 at 115 in the quarter
Old 09-09-2009, 09:21 AM
  #18  
LS1Tech Co-Founder
iTrader: (34)
 
Pro Stock John's Avatar
 
Join Date: Nov 2001
Location: Chicago, IL
Posts: 44,653
Received 1,099 Likes on 721 Posts

Default

I ran a similar combo to that, as did some friends, back around 2000. Getting into the high 1.4's and running some 11.4-11.5's should be doable before you start looking for ways to make the car quicker (like changing intakes, electric water pumps, more gear). We mostly ran the Yank TP4400. I would run something like that at a minimum if you really want max ET.

I had a Fuddle 8" 4800 (TH400) in the 2000 white Camaro, went 1.48 NA and 1.38 150 shot. This was at 3300 raceweight. That converter was still very streetable. Was going 123mph with an unported LS2 intake, and stock water pump. Car has since gone 10.7@126mph with 5500 converter and ported FAST 90 intake, though probably not launched at full rpms.
Old 09-09-2009, 09:50 AM
  #19  
TECH Fanatic
Thread Starter
iTrader: (2)
 
stumprrp's Avatar
 
Join Date: Aug 2007
Location: Rhode Island
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts

Default

thanks for the great info John, i have a PP 96mm intake and 90mm throttle body waiting to go on, but i think ill scrap it for a restall and some tires man.
Old 09-09-2009, 10:25 AM
  #20  
11 Second Club
iTrader: (14)
 
Camaro396's Avatar
 
Join Date: Oct 2005
Location: Toledo, Oh
Posts: 5,091
Likes: 0
Received 7 Likes on 7 Posts

Default

I used a 239/242 .649"/.609" 111LSA camshaft with a stock bottom end/stock heads setup, and use an Ultimate Converter Concepts 5000 stall, and switching to 4.56 gears. I loved the setup, before my trans broke.


Quick Reply: Optimal Converter Stall Speed / Shift Ext.



All times are GMT -5. The time now is 11:05 AM.