Guest Mike Posted February 7, 2007 Share Posted February 7, 2007 I searched but didn't find anything specific to my question... Please... no advice on my choice of power-plant or which transmission to use. I've made my decision and my little pee-sized brain is too sore for any further thought on that subject. I need transmission advice only as follows... INFORMATION 1: I'm looking for a 4L80 with or without full auto shifting. The latter is preferable but not mandatory. I do want the OD lock-up too. This will bolt up to either a SBC 434 stroker w/ NO2 or a BBC 572 N/A. Whichever motor I choose will have ~700/700 HP/TQ. This is a daily driver and will seldom see the strip. I won't be racing auto-x, etc. I'll have a 3.15 diff with a Power Brute CLSD. Frame mods are in the plans to handle the torque. INFORMATION 2: I may have found a decent deal on a 4L80E with factory ECU and stock converter. I'm sinking a lot of cash into the new motor so I need to TRY to keep my costs down on the transmission. QUESTION 1: Will the stock 4L80E stay together with my motor... NOTE: The car only weighs 2350-2450 lbs empty/dry (depending on engine choice). QUESTION 2: Will the factory ECU work on my old Z with a Gen1 motor? QUESTION 3: Will the stock converter suffice (for now) given the weight of the vehicle? NOTE: I do intend to run this through the 1/4 occasionally with drag slicks. So I might upgrade to a stall converter later if I can get the drag slicks to hook up, that is. APOLOGY 1: For my ignorance Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 7, 2007 Share Posted February 7, 2007 I believe that mecanicaly, the tranny and convertor would hold together, as long as you don't beat the car to death evry time you drive.. Me and a buddy rebuilt/rodded his truck last winter (91 gm 1 ton dually) and the stock 4L80E has held up fine behind the mild 454 (Close to 400hp, maybe.. 600lbs torque?) which is just over half the power you want to run.. BUT; this is a 6000lb truck with a 3:73 rear end, and it gets DRIVEN if you know what I mean. Thing is.. I *think* the tranny needs the input from an FI motor to properly shift/lock up/ect... and a speed signal as well. (stock GMs ussualy send from the back of the spedo to the ECU) Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted February 8, 2007 Share Posted February 8, 2007 Thanks for sharing that info. Yeah I know these are tough trannies. I had several old 400 and 455 CID Firebirds with TH400's and I couldn't kill any of them. I just wasn't quite sure how the newer 4L80E would react to 700HP. What input is needed from the FI motor? Is this something I can work around? I've been planning on replacing my gauges soon... so I might as well do that now. Autometer (I think) has some really nice electronic/programmable speedos in their ?Vintage Gold? line. I assume the output from this will work. Quote Link to comment Share on other sites More sharing options...
Dudeboy Posted February 8, 2007 Share Posted February 8, 2007 Give Bowtie overdrives a call, they can steer you in the right direction.They have the transmission controller that can work with a carburated motor. http://www.bowtieoverdrives.com/catalog/catalog_inc/viewitem.php?ITEMID=372 Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted February 8, 2007 Share Posted February 8, 2007 Hey Glenn... Thanks for the link. BTO units are really nice but I'm trying to do the transmission swap as cheaply as possible (for now). The BTO control unit is a whopping $1100:shock: Is there a work-around to make the factory ECU work with a carb? Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted February 8, 2007 Share Posted February 8, 2007 The stock 4L80 will need to have the direct clutches dual fed and a 34 element sprag added to reliably handle 700 HP/TQ. I am building one right now for similar power levels but it is a full manual setup. Other than that it is a pretty solid trans as is. If you get much higher a billet input shaft and forward hub ($100 or so) become a wise upgrade. TCi has the lowest cost controller on the market at about $650. The Compushift is quite a bit more expensive at over $1000. PCS also makes a controller for ~$800 IIRC. The stock GM stand alone controller was for diesel engines and I haven't ever seen anybody successfully use it. I've heard rumors... In any case by the time you buy it, a harness, and the equipment to reburn the chips, you could have an easily programmed TCi unit. Sometimes there just isn't a cheap way out. The stock converter would also fail doing WOT lockup at 700 lb/ft but would be fine if driven "normal". However a stock converter is heavy and a low stall speed (truck applications). My suggestion is to buy a transmission built to handle the power level you ultimately intend, either go with a full manual setup, or buy the controller, and then buy a quality converter. If you plan to use lockup under WOT, buy a multi-disc unit. ~$1000 for the converter. If you want a quality single disc converter you are looking at ~$700. Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted February 8, 2007 Share Posted February 8, 2007 Thanks jakeshoe. I found a 4L80E for $600 shipped that's claimed to be "working very well" and it includes the factory torque converter and ECU. I found another one for $450 shipped that is a supposed "recent rebuild". This one has the factory converter and the guy thinks he can find the ECU which he'll include... "if" he finds it. As a side note, the first seller says he knows a guy who works for one of the companies that makes aftermarket controllers. He thinks he can get one for me pretty cheap. I don't know what company nor do I know the price. So... assuming I get a working ECU for free... is there a work-around to make it work with a carbed engine? OR... am I better off re-selling the factory ECU and buying a purpose-built unit? NOTE: I can always upgrade later:mrgreen: Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted February 8, 2007 Share Posted February 8, 2007 The factory "stand-alone" TCM was used only on diesels. Unless you want WOT shift points at 2500 rpm, it would need to be re-programmed. I haven't heard of anybody having success with that approach. Not to say it can't be done, but you would be on the learning curve. If you burn up the trans learning, its about $500 in parts to rebuild it (stock), plus labor, converter that will be contaminated, etc. You could probably find a good working wrecking yard 4L80E for $600-1000. But it still needs to be broken into for a 34 element sprag, dual feeding the direct clutches, new filter, pan gasket, etc. That's ~$200 worth of parts alone and about 1/2 of the rebuild price for labor. Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted February 8, 2007 Share Posted February 8, 2007 Ahh... now my thick little skull has absorbed what you're saying. I found another L480E for $450 shipped with stock converter but no ECU. The seller tells me that he was told it was "recently rebuilt" just before he bought the truck. He's parting out the truck because he only wanted the motor. He said he pulled the pan and it's completely clean and the fluid is bright cherry red. So it's probably "recently rebuilt" but who knows what that really means? Hopefully this one will stay together long enough for me to raise the cash for a decent rebuild. The price is right at least. Is a factory ECU worth anything? How much can I expect to get for one? Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 10, 2007 Share Posted February 10, 2007 I just had a thought... it would be a bit of messing around, but I'll bet it could be done.. If you were to somehow 'fake' the proper signals to the ecu, the factory ecu would work the tranny for you.. I'm thinking in terms of a throttle body injected motor here... What I mean is; Somehow attach a tps to your carb along with the tv cable, use... led's (or something?) in place of the injectors, pull a signal off the dizzy (ecu needs to see it to adjust timing) and install an 02 sensor.. (this would help with tuning anyway, or if you wanted an A/F guage) Basicaly tell the ecu that your motor is running/under throttle and it SHOULD shift the tranny... I'm not sure if you'd need ALL the sensors hooked up, maybe just the tps/tv cable.. My truck (91 tbi 454) ran and drove fine with the 02 wire broken off, knock sensor hanging by it's wire, and a bad temp sensor! Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted February 10, 2007 Share Posted February 10, 2007 DATSUNLOVER... Thanks for the great ideas. As per JAKESHOE's post and advice from some others, I'd still have to somehow reprogram the factor ECU to change the shift points. This can probably be done via replacement of a few components and/or reprogramming any EPROM(s) which may be present. I just don't know. And... I'm not smart enough to do that anyway. I like your idea of mounting a TPS to the carb. I would think that all the ECU needs to properly shift the tranny is a TV cable, TPS, vaccum sensor, and RPM input. But... I dunno. I would guess that the aftermarket ECU's don't need the TPS. And of course they shift at higher RPM's than the factory diesel ECU's. Sitting here... drumbing my fingers... frustrated... Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 11, 2007 Share Posted February 11, 2007 ACTually.. I can't find the link now, but there IS an adaptor bracket you can buy to run a tps on a carb.. As for re-programing, I'll ask my buddy tomorrow where he got his program.. (he has the 2wd 454 dually we built last year) Somewhere online I believe he found a windows based program that is compatable with this programable eprom unit he bought (I'll try to get the name brand) He was showing it to me last week.. really cool set up; it gives you fuel maps based on tps/rpm, you can change shift points, ect. It is basicaly a piggyback unit that you plug into the ecu in place of the stock prom, and you simply download your setup to it, and plug it into the ecu. I believe it also allows you to make changes on the fly, IE while the vehicle is running. Edit; http://www.twistmachine.com/products/shrifter.html I was on that site, and one of the links shows the bracket.. http://www.jegs.com/webapp/wcs/stores/servlet/product2_10001_10002_747891_-1 Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted February 11, 2007 Share Posted February 11, 2007 There is no TV cable on a 4L80E or 4L60E, etc. The line pressure is controlled by the EPC (Electronic Pressure controller). You still need a TPS with an aftermarket controller. You can fabricate something or use the TCI setup. TCI controller is ~$650 from Jegs, etc. TPS setup is another $200. I am working on a deal to become a dealer for the TCI stuff so I can incorporate it into my transmission packages. Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted February 11, 2007 Share Posted February 11, 2007 Thanks Jake. This car customizing $#IT is expensive... Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 11, 2007 Share Posted February 11, 2007 There is no TV cable on a 4L80E or 4L60E, etc.. Really? I'm gona have a look under my hood tomorrow.. I swear there is another cable attached under the throttle cable at the throttle body... (91 gmc 454 4x4 1 ton truck) Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted February 11, 2007 Share Posted February 11, 2007 I assure you, there is no TV cable on a 4L60-E or 4L80-E. You are probably seeing a cruise control cable. Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 11, 2007 Share Posted February 11, 2007 Well it's midnight here right now, and freaking cold+snowing... so I'll take your word for it. I'll probly be under the hood tomorrow anyway, beating on the wiper motor to make it work.. Quote Link to comment Share on other sites More sharing options...
jakeshoe Posted February 11, 2007 Share Posted February 11, 2007 You need to put a new circuit board in the wiper motor, common failure on those trucks. I think parts stores carry them now. Quote Link to comment Share on other sites More sharing options...
bschiltz Posted February 12, 2007 Share Posted February 12, 2007 TV cables are on the 700r4 (or 4l60... no "e") which look mostly the same as the 4l60-e. The "e" stands for electric controlled. Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 12, 2007 Share Posted February 12, 2007 Heh.. funny thing... turns out the wiper motor problem was a GROUND issue! Temporary fix is a piece of wire under one of the mounting bolts and running around to the back of the casing, sandwiched to the firewall. I know, hack.. Anyway, my buddy says the piggyback unit he has runs about $150 and you can find the software online.. each motor/prom has a diffrent program (specific to the year/model) and costs around $40-$60. Tunnercat is the name I think.. (sorry, don't have the links, he said he'll email them to me) Quote Link to comment Share on other sites More sharing options...
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