locking a converter on the dyno
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TECH Fanatic
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From: upstate ny
locking a converter on the dyno Can this cause damage to your converter? How much more horse do you see by locking you converter? I am Dynoing on a dynojet on 6/13 and I want to lock the converter for one pull, but I dont want to damage it. thx in advance.
Launching!
Joined: May 2003
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From: Canadian West Coast
Usually you gain about 3-5% more rwhp with TC locked (and less torque).
I believe it is a little harder on the tranny, but I think it is moreso at the end of the run when you let off - and it's not like its the worst thing you can do to the tranny. Just shift into neutral at the end of the run to let the motor slow down.
If you are worried that you are going to cause serious damage, don't worry. Its not any worse stress really than just being on the dyno in the first place.
I believe it is a little harder on the tranny, but I think it is moreso at the end of the run when you let off - and it's not like its the worst thing you can do to the tranny. Just shift into neutral at the end of the run to let the motor slow down.
If you are worried that you are going to cause serious damage, don't worry. Its not any worse stress really than just being on the dyno in the first place.
I would lock the convertor the whole time you tune so that way when the convertor is unlocked, its a gaurentee it wont ping. Plus, if you tune it locked, its basicly fully loaded.
Rick
Rick
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From: upstate ny
Originally Posted by Rick@Synergy
I would lock the convertor the whole time you tune so that way when the convertor is unlocked, its a gaurentee it wont ping. Plus, if you tune it locked, its basicly fully loaded.
Rick
Rick
Originally Posted by nasty99WS6
Why is it a guarantee that the car wont ping if you tune w/the converter locked?
Thread Starter
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From: upstate ny
Originally Posted by Rick@Synergy
BEcause a locked convertor will produce more load on the car just like a 6-speed will. Its more of a direct drive, instead of a slip.
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Originally Posted by nasty99WS6
ok. thanks. 1 Last question though, is it bad for the converter?
YES. The lockup clutch in a torque converter is TINY. It's an EMISSIONS device. It is not made to carry the load of the car at WOT. There is no need to lock it up other then for Brag racing.
If that clutch comes apart, so will you transmission. Do NOT do it unless you are prepared to replace your transmission for 3-5% more HP on a Dynojet.
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TECH Junkie
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From: its fucking cold
Originally Posted by Tech
YES. The lockup clutch in a torque converter is TINY. It's an EMISSIONS device. It is not made to carry the load of the car at WOT. There is no need to lock it up other then for Brag racing.
If that clutch comes apart, so will you transmission. Do NOT do it unless you are prepared to replace your transmission for 3-5% more HP on a Dynojet.
If that clutch comes apart, so will you transmission. Do NOT do it unless you are prepared to replace your transmission for 3-5% more HP on a Dynojet.
Originally Posted by Tech
YES. The lockup clutch in a torque converter is TINY. It's an EMISSIONS device. It is not made to carry the load of the car at WOT. There is no need to lock it up other then for Brag racing.
If that clutch comes apart, so will you transmission. Do NOT do it unless you are prepared to replace your transmission for 3-5% more HP on a Dynojet.
If that clutch comes apart, so will you transmission. Do NOT do it unless you are prepared to replace your transmission for 3-5% more HP on a Dynojet.
You have to lock the convertor if you do steady state tuning. This is the only way you will be able to tune all parts of the table.
Rick
Originally Posted by nasty99WS6
what is steady state tuning?
Steady state tuning means that you are tuning the whole table. My dyno allows me to lock in at any RPM and tune everything all the way down to 400RPM's. This method is done by engine builders and car builders like GM and everyone else. Thats how they build tables for your PCM.
I dont fully agree with locking the convertor is a bad thing. Look how many people lock the convertors for drag racing. Even all the turbo guys do it.
Rick
Locking the converter under light throtte is fine. IMHO, locking a converter at WOT is bad news especially if there is a brake on the dyno. No need to get data from cells the car will never hit. Just make sure the tables are smooth. 
Teching In
Joined: Jun 2005
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From: Conover, NC
Man, there's a lot of diff. opinions on this one. I lock the converter when I'm steady state tuning on my Mustang 1100SE eddy current dyno. When I do power pulls I just lock the car in 3rd gear with the scanner and leave the converter unlocked. Most of the time locking is ok, but I have had a tranny burp fluid out (overheat) before with the coverter locked. Steady State is something most Dyno Jet owners don't know about. It's the only way to tune an EFI system, especially for street applications. If your only doing the 1/4 or the 1/8th then you can tune just for the cells that you hit by tuning your log files with a wide band. While this will get you close on the street, it will never replace a good steady state tune on a real dyno ie Mustang, Dyno Dynamics, Superflow. When in steady state you can see the hp and tq at that instant and add or subtract timing to see where your max. power is at. This allows you to not have too much timing and run the risk of detonation. There are other advantages there too.
Aaron Lail
Tru Dyno Sports LLC
1901C Conover Blvd. E.
Conover, NC 28613
www.trudynosports.com
(828) 459-0088
Aaron Lail
Tru Dyno Sports LLC
1901C Conover Blvd. E.
Conover, NC 28613
www.trudynosports.com
(828) 459-0088
Originally Posted by TruDynoSports
Man, there's a lot of diff. opinions on this one. I lock the converter when I'm steady state tuning on my Mustang 1100SE eddy current dyno. When I do power pulls I just lock the car in 3rd gear with the scanner and leave the converter unlocked. Most of the time locking is ok, but I have had a tranny burp fluid out (overheat) before with the coverter locked. Steady State is something most Dyno Jet owners don't know about. It's the only way to tune an EFI system, especially for street applications. If your only doing the 1/4 or the 1/8th then you can tune just for the cells that you hit by tuning your log files with a wide band. While this will get you close on the street, it will never replace a good steady state tune on a real dyno ie Mustang, Dyno Dynamics, Superflow. When in steady state you can see the hp and tq at that instant and add or subtract timing to see where your max. power is at. This allows you to not have too much timing and run the risk of detonation. There are other advantages there too.
Aaron Lail
Tru Dyno Sports LLC
1901C Conover Blvd. E.
Conover, NC 28613
www.trudynosports.com
(828) 459-0088
Aaron Lail
Tru Dyno Sports LLC
1901C Conover Blvd. E.
Conover, NC 28613
www.trudynosports.com
(828) 459-0088
You took the words right out of my mouth. I cant see why anyone would just settle for a WOT tune. I bought my Dynapack for that reason, Tuning. Any EFI car needs it. Thats what EFI is.
Rick
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From: upstate ny
well, I ran it on the dynojet today and he did a 2nd gear pull. resulted in 363 rwhp, and 340 rwtq. He said that 3rd gear probly would have been 3%higher. That was with the converter unlocked. I just dyno'd, no tune.
Originally Posted by nasty99WS6
well, I ran it on the dynojet today and he did a 2nd gear pull. resulted in 363 rwhp, and 340 rwtq. He said that 3rd gear probly would have been 3%higher. That was with the converter unlocked. I just dyno'd, no tune.
LOL. Yeah, WTF? Tell him you want your money back. You should have dyno'd in 3rd.
Most folks who are serious about tuning spend more time on the street/strip tuning then they do on the dyno. In this case, he was asking about WOT on a dyno. Specifically, a Dynojet.
Most folks who are serious about tuning spend more time on the street/strip tuning then they do on the dyno. In this case, he was asking about WOT on a dyno. Specifically, a Dynojet.