very cool. cant wait to see the pictures and dyno sheets.

 

Can you show the pics of the b4 and after all cog pls..

 

If I can find a pic of the stock Vortech in my car . I'll look on my puter when I post the new ones .

 

How is ur belts holding up??

 

If I run them with a 1/2 inch of play both ways . They dont last long . Running them a little tighter....no problems so far . Might go with the GTM idler pulley on the blower

 

You really think that every dyno from a mustang dyno that is posted is altered? Only your dyno jet gives real numbers and every mustang dyno is altered because the the user can change the settings for each car. JT get real, news flash there's more than 1 dyno around that can give honest numbers.

Booger sorry for the OT he spews this dyno BS all the time.

 

In for pics

 

tranny's don't break off HP.. they break off TQ

 

Are you sure it was slipping? I would love to see the dyno graph. The high stall converter eats up horsepower (put a temp gauge on your tranny line to see where all your hp is going) - have got a little R&D project going with Andre at Edge converters. Will let you know how it turns out.

 

It may be because of the upgraded TC...

 

I had thought of calling him and seeing if he can help out with increasing the holding power of the TC . Actually going away from a higher stall and just going for full out trq.

 

I think you are on the right track. Why didn't you post this earlier (like a year ago!)? I just sent in a TC from an 06 - I "think" it will fit my 04, but won't know for sure till I try.

The TC stall speed is a function of torque input and what is termed the "k factor", which is fixed at the time the TC is built/designed, K = stall_rpm/sqrt(torque). The more power you've got, the higher your stall will be without any change to the TC. The GTM TC (built by Andre at Edge Racing I believe) was spec'd at 3200 rpms, but at 12 psi, it actually stalls closer to 4.6k rpms! Spool is instantaneous when you floor it and the car is a rocket, but talk about slipping and drivetrain losses. Unlike TC for other cars, you can't buy a lighter or smaller unit to help with drivetrain loss to offset the increased slipping with a high stall converter. Most vendors will upgrade your OEM unit (correct me if I'm wrong - would love to see more choices).

So using data from a 12 psi run, the K factor for my GTM TC is 4600rpm/sqrt(420tq) = approximately 224. On a stock engine putting out say 230 tq, stall would be 224*sqrt(230), or about a 3500 rpm stall. A little higher than what I thought I was getting but not too far off. Once you know the K factor for your TC, you can calculate the stall speed for any given input torque.

For this 2nd TC, I've asked for an increased stall ratio (torque multiplication at launch is a function of the stator where stock is 2.0 but Andre can raise to 2.5 or so without any issue), lowered stall and increased coupling efficiency through tighter clearances. The goal is to have a 3500 rpm stall at 500tq. So that would represent a K factor of 156 (big difference from 1st upgraded TC). On a stock engine, the stall speed would be only 2300 rpms (stock stall is 2600-2900 rpms per FSM).

EDIT: Just so you know, I'm not really pursuing this in a quest for more power to the wheels (though that is always nice ). The 5AT quickly get very, very hot (240+ degrees F). Yes, I have a tranny cooler right in the path of airflow. I was going to upgrade this or put two in parallel, when I started thinking about where all this heat was coming from...

 

^^^^^^^Well that was way over my head . But thanks for explaining it . Sounds like a complete tranny swap would be the best way to get more whp to the ground . But dont know if it is doable cost wise .

 

Well the short version of my post is that your stock TC may be better than the upgraded one, all said and done, as it may be more efficient in putting the power to the ground. We'll see as I test the theory going to the opposite end of the spectrum with the 2nd TC...

 

Raj...does the K factor = the true stall. I really need to figure out this transmission so I can get the full potential of my motor. I'm so confused

JT has the dyno sheet so I'll see if he can post it.

 

Yes...let us know how it comes out . May look for a stock TC

 

This is a gamble for me - I honestly couldn't find a great answer for our platform so I'm going to compare the 2 converters. If the 2nd one sucks, then I'll put the first one back in, cause it sure feels fast - and deal with the heat issue.

The K factor is a constant that describes how the true stall is affected by the input torque. Show me a dyno graph and I can tell you approximately what the K factor is for your TC. Based on your old thread (the one with nitrous giving you around 460 whp), I think you have a converter with the exact same specifications as mine (also built by Andre at Edge, correct)? You thought you were getting a 3200 rpm stall, but with nitrous it was closer to 4200-4500?

With my 700bb turbos (and your almost identical APS turbos), turbo lag is not much of an issue. We don't need a high stall converter to spool up the turbos quickly. I think the converters we have would be ideal for something like the APS extreme kit or SFR turbos, where peak power and airflow isn't an issue but spool is. Ideally, I think we want the most efficient, tightest fluid coupling possible. What lag there is will be exaggerated and that may not feel good ("bogging prior to spool"), but keep in mind that torque at launch is aided by torque multiplication - and that is still increased with an upgraded converter (from 2 to 2.5 x input torque for the first 60' or so). The trade off should be more power to the ground in gears 2 and up. I won't have more data for about 3 weeks when I get my TC back from Andre and installed at the local dealer... I just hope no one mucks anything up cause the car is running great right now. But I'm curious what affect this will have, so I can't resist wasting some more money.

 

Raj....yes I did have mine done by Andre and IIRC on my old dyno sheet you are real close on the numbers. Would this make any sense based on your theory/formulas, to have the true stall set (rpm) at where you're making peak torque (rpm) at. I remember reading something about that.....

Also when you mention that your goal for the new TC is to have 500tq @ 3500rpm, is the 3500 rpm a brake stall # or a true stall#. If its a true stall # then I think the brake stall would put you back right around what the OEM TC one is (2600-2900).........help me understand

 

Yes, you are correct - I am talking only about true stall. My understanding is that the OEM TC true stall is 2600-2900 depending on input torque. Brake stall will be less, how much less depending on braking ability. And many do recommend having your true stall within 500 rpms of your peak torque. That maximizes the car's ability to move into the powerband. On the 1/4 mile the launch is so important for the ET, that I think the TC specs we have now (regardless of dropped peak power) may well be faster. Are you able to go WOT in 1st gear though? Even with sticky tires? I think it's possible with our relative small twin turbo setups to design a TC that is more efficient and doesn't hurt ET too much. For a dedicated drag car, it'd be a tough call, but I drive mine on the street every day, on street tires - so it's a no brainer to move to something that is more efficient.

 

My belts are still shredding up.. but not as fast.. Ill get a dyno again this friday.. see where im sitting... bad thing is that im doing a 1.5hr drive to get to the dyno.....