Any Problems Associated with Torque Converter Upgrade?
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Driver School Candidate
Joined: Nov 2001
Posts: 22
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From: Alameda
Any Problems Associated with Torque Converter Upgrade?
Hello everyone out there. I was considering a torque converter upgrade with a 2800 rpm stall but after talking to someone at Vic Hubbards Speed & Marine, I am having 2nd thoughts. He told me that it will be fine for local driving and you will notice a big improvement in acceleration but if you were to take the car on long drives on the freeway, the torque converter will boil over your tranny fluid regardless of sythetic or not and will eventually lead to premature transmission failure. I want the performance but am not willing to trade off with reliability. Has anyone out there had any transmission problems after installing a high stall torque converter? If so, how long before you noticed any problems. Thanks for your replies.
Lexus Test Driver
Joined: Feb 2001
Posts: 1,199
Likes: 1
From: Alabama
BS!
Lite - Whatever U do, DON'T let that shop install your convertor because they're idiots!!
I averaged 92 mph coming back from Orlando in June for 700+ miles & the car never came close to overheating not did the fluid smell burned when I checked things over back at the house. I've had it for almost 2 years with no tranny related problems although I do have a tranny cooler as well. Mine is also the 2800 rpm stall Dragon convertor made by Precision Industries. All U can look forward to beside improved acceleration is a slight ( 1 mpg ) loss of fuel economy on the highway due to the excess slippage of the T/C. Yes, this is the same slippage that will cause additional heat in the tranny but it won't be enough to boil over the fluid so go ahead with the mod!!
I averaged 92 mph coming back from Orlando in June for 700+ miles & the car never came close to overheating not did the fluid smell burned when I checked things over back at the house. I've had it for almost 2 years with no tranny related problems although I do have a tranny cooler as well. Mine is also the 2800 rpm stall Dragon convertor made by Precision Industries. All U can look forward to beside improved acceleration is a slight ( 1 mpg ) loss of fuel economy on the highway due to the excess slippage of the T/C. Yes, this is the same slippage that will cause additional heat in the tranny but it won't be enough to boil over the fluid so go ahead with the mod!!
Pole Position
Joined: May 2001
Posts: 2,465
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From: Illinois
Extra slippage?
I sure hope you are wrong Gene. Most of the aftermarket converters (unless for serious drag use) have a lock-up feature. On the expressway you should be locked up and not have any slippage. Do you know for a fact that the PI converter doesn't lock up? Perhaps the 1 MPG difference is associated with a slightly heavier foot after the install?!?
Peter
Peter
Lexus Champion
Joined: Jul 2001
Posts: 3,861
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From: North Carolina
Re: Any Problems Associated with Torque Converter Upgrade?
Originally posted by Litespeeds
He told me that it will be fine for local driving and you will notice a big improvement in acceleration but if you were to take the car on long drives on the freeway, the torque converter will boil over your tranny fluid.......
He told me that it will be fine for local driving and you will notice a big improvement in acceleration but if you were to take the car on long drives on the freeway, the torque converter will boil over your tranny fluid.......
I had mine installed about 2 weeks ago, and drove for 5 hours straight on my return trip with out any issues. I do HWY driving everyday since then with no issues.
I am getting my PermaCool cooler installed this weekend. In fact, the local dealer will be doing it after I (just a minute ago) convinced the shop foreman it was preally straight forward install.
Sounds like the shop just doesn't want to do the work because they are incapable, or just lazy.
I'd give SRT a call, and speak to Mo. He is most knowledgeable when it comes to GSs, esp about installing these TCs.
Keep us posted.
Driver
Joined: Sep 2001
Posts: 190
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Make SURE that you have the converter bolts ground down per the special instructions, or you will risk a seal, a pump and the main shaft bearing for the tranny/convertor.
I didn't have the bolts ground when I put my purple dragon in my SC400 and it caused a lot of problems. Prescision Industries repaired my convertor, but I had to cough up the extra money for the removal/and re-install. Otherwise, everything is just fine, no boil over even at 120 mph for 5-10 minute runs.
FOLLOW THE INSTRUCTIONS TO THE LETTER!!!
I didn't have the bolts ground when I put my purple dragon in my SC400 and it caused a lot of problems. Prescision Industries repaired my convertor, but I had to cough up the extra money for the removal/and re-install. Otherwise, everything is just fine, no boil over even at 120 mph for 5-10 minute runs.
FOLLOW THE INSTRUCTIONS TO THE LETTER!!!
Lexus Champion
Joined: Jul 2001
Posts: 3,861
Likes: 4
From: North Carolina
Re: converter
Originally posted by FD143
Are you guys running the converters notice higher rpms while cruising than with the factory converter????
Are you guys running the converters notice higher rpms while cruising than with the factory converter????
Highway cruising? No; none at all. Once the gear is set, the TC doesn't affect the cruising RPM. The TC slips more at the low end to allow the transmission to reach higher RPMS (higher torque) beofre it locks up.
In the most simplieifed terms, its like holding your foot on the brake for a second while pushing the on the gas, then letting off the brake.
HTH
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Lexus Test Driver
Joined: Feb 2001
Posts: 1,199
Likes: 1
From: Alabama
Right!
Peter - Actually, the Dragon IS a lockup convertor but isn't that feature rpm dependent?
Not that up on lockup T/C's but I thought that the Dragon wouldn't completely lock up until the engine exceeded the 2800 stall speed. Kinda figured that was part of the reason that I averaged only 1 mpg less on that Florida cruise plus the 3.76 gears kept the rpms around 3400-3500 & right in the powerband. Or does the lock-up feature take effect when the engine rpms settle on a steady cruise rpm? Seems like my GS still slips a little if I'm cruising at 2200 & give a little extra throttle pressure. But there's NO DOUBT about your last statement of the "heavier foot" being correct!! It's true; it's true!!!
Not that up on lockup T/C's but I thought that the Dragon wouldn't completely lock up until the engine exceeded the 2800 stall speed. Kinda figured that was part of the reason that I averaged only 1 mpg less on that Florida cruise plus the 3.76 gears kept the rpms around 3400-3500 & right in the powerband. Or does the lock-up feature take effect when the engine rpms settle on a steady cruise rpm? Seems like my GS still slips a little if I'm cruising at 2200 & give a little extra throttle pressure. But there's NO DOUBT about your last statement of the "heavier foot" being correct!! It's true; it's true!!!
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