This has always been my understanding too -- the torque converter is where the majority of the heat is generated. And it makes sense if you've ever studied how they work. I can't see how a non-lockup would generate LESS heat. And everything I've ever read about automatics will describe heat as Enemy #1.
When you're in Drive or O/D, it's easy to be going a constant speed, and hit the gas pedal mometarily, and see the revs rise without a corresponding increase in vehicle speed. The engine just spun faster, consuming more fuel, generating more energy, but we didn't see the vehicle increase in speed. Where did that energy go? You just heated up the fluid in the trans to some degree via a pumping/shearing action inside the converter. It's entirely possible that some of these trans guys don't have much faith in the strength/durability of the clutch or locking mechanism inside the lock-up converters (esp. behind a strong engine), thus their non-lockup recommendation, but a non-lockup WILL generate more heat. You need to make sure you have appropriate trans cooler for such a situation. -Dave -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mike Holleman Sent: Thursday, February 03, 2005 9:00 AM To: The Chevelle Mailing List Subject: Re: [Chevelle-list] th700R4 As in many cases we have to depend on the "experts" to guide us through the technical aspects of building our rides. And the experts seem to have differences of opinion. What I'm not sure I understand is that I have always been lead to believe that an unlocked converter builds more heat than one that is locked. My personal experience seems to bare this out as my 700R4 runs as much as 15 degrees hotter in third gear when driven over a period than it does in OD and locked. Heat only seems to be a factor when I am driving mostly in town and not getting up to enough speed to go OD. These observations are with a constant engine temp of 180, which is where the 421 seems to stay. A 38 Coupe huh? Sounds like a nice project. Mike ----- Original Message ----- From: "Wayne" <[EMAIL PROTECTED]> To: "The Chevelle Mailing List" <[email protected]> Sent: Thursday, February 03, 2005 8:04 AM Subject: Re: [Chevelle-list] th700R4 > Mike. That's what he was trying to explain to me. About the Fluid/oil > circuit in lock up and none lock up. and how with the manufacturing of new > aftermarket parts > Your better off in the none lock build... I was looking over some of my > Overdrive stuff when I went down this road a few years ago. and at that > time > Spoke to Art Car , he had just opened his new shop, and he was firm in > his beliefs to use None Lock up. But the cost in 2000 added 400 extra to > the build...he laso opted for the th200r4 but stressed a long list of > upgrades...to mke it survive from it's lowly low hp stock build. > > The extra Heat is from the converter in 4th Gear/ Over Drive. in it's LOCK > UP mode. It shuts off the oil circulation as part of the Lock Up > process. > This is one reason my builder says.. keep it loose, keep it cool and , keep > it unlocked.. > > > > Thanks for the input guys.. > .If I did not Drive the wheel off my cars. I would opt for a built TH-400.. > but I am sooooo spoiled with my Elky and it's over drive > > Wayne > > > > > ----- Original Message ----- > From: "Mike Holleman" <[EMAIL PROTECTED]> > To: "The Chevelle Mailing List" <[email protected]> > Sent: Wednesday, February 02, 2005 6:28 PM > Subject: Re: [Chevelle-list] th700R4 > > > > Wayne, I have a 700R4 behind a built 421 tripower in my 64 Tempest. I am > > using a lockup converter w/manual switch because it was highly recommended > > by Bowtie Overdrives, which is where the trans came from. Their reasoning > > was because of heat created by converter slippage in overdrive. My > > converter > > only locks in overdrive and I do see a substantial difference in trans > > temp > > when I drive alot in third versus in OD. BTO says the trans temp should > > not > > be much above 150 for extended periods. The only time I see higher temps > > is > > on hot days when I am not getting into OD/lockup mode. Hope this helps. > > Mike Holleman > > > > > > ----- Original Message ----- > > From: "Wayne" <[EMAIL PROTECTED]> > > To: "The Chevelle Mailing List" <[email protected]> > > Sent: Wednesday, February 02, 2005 1:01 PM > > Subject: [Chevelle-list] th700R4 > > > > > >> I am gathering parts from my up coming street rod Project. 38 chevy > >> coupe. > > I > >> have a 700 R4 in my 65 Elky and like it . > >> I stoped at the local HP trans builder. and we talked about what I > >> wanted...He suggested a 89 later with all the transgo stuff HD sun > >> shell > >> 39 sprag and 13 vane pump.. ect But also said " In his opnion" He > >> would > >> prefer I use a NONE lock up converter with the none lock up valve and > > none > >> lock up converter... > >> 2000-2300 RPM none lock up converter and modified to run full fluid/oil > >> flow in 4th gear. > >> This will go behind a ZZ4 350 with the LT1 hot Cam (395 HP and 425 ftlb > >> tourque) 9" ford .370 rear and 3300 LB aprox. > >> > >> Any feedback on the None lockup VS Lock up ? > >> > >> Wayne > >> ACES 1556 > >> TC 186 > >> > >> Ps I use the TCI scheme lock up with a vacumn switch on the elky.. > >> > >> > >> > > > > > > >
