hey guys ive just removed a 304 and turbo 700 from a donor car but as i was removing the engine ive forgot to remove a plug from the tranny and its broken the plug on the tranny its a square 4 pin plug. what is this for cheers Allan

Inhibitor switch and I think from memory the lockup converter signal is there too, I just thought I'd mention if you ever plan on running any reasonable amount of power through thje combo get rid of the th700 now before you spend any money on it. ---------- Post added 08-04-12 at 18:10 ---------- Sorry I should have asked is it a VN/VP Th700/4l60 or the later 4L60E electric controlled unit?

afew years back you'd ditch them, these days they can be done just as strong for the same kind of money.

its from a vq stato. so if ive broken the switch am i best to get it repaired or just buy another box was thinking maybe a turbo 350/400

Well mine started off like yours VN 304 and TH700, all it had was a VS S3 airbox and full exhaust and memcal, took a month and the T700 started to slip on 2 to 3 change, then the 1 to 2 change as well and a few weeks after it started slipping in first and second whenever it was over 4000rpm. Now I couldn't guess how many kays it had done or the life it lived before so I started some online research to see what's possible in terms of building it strong enough to handle the GT35/40 I was setting up for it. Now I remember back when I still worked as a mechanic these boxes used to cook fairly easily if driven hard especially if TV cable adjustment was wrong. Well after a couple of weeks of reading I found that 50% of people said you can build them tough as nails including one guy who claims he runs constant low 11s with one with no problem ever. And 50% of people said they were a piece of **** (my experience agrees) and no matter what aftermarket gear you use they will fry with any amount of reasonable power. So I got on the phone and rang 5 melbourne based performance auto builders and asked for a turbo charged 304 making around 300rwkw what they would recommend for reliability...4 said th350, 1 said Trimatic ($5500 quote) not one thought it was possible to make the t700 reliable at that power limit with any amount of money. So I did some more reading and found that the TH400 uses about 4 more horespower than the TH350 to run it...but cost next to nothing to build in comparison to the 350 or trimatic because it starts of as a fairly chunky box. The factory conservatively rates them safe for 450ft pound of torque. My car is just a weekender with a rare track run so the extra 4 or 5 hp lost to run it didn't worry me, also with the 400 I'm able to retain full auto shift and should take the abuse...I guess we will know soon as the parts for the auto are being shipped as we speak.

problem is, alot of auto places wont touch the 700s cos of the cost and headaches and the age old story. just go across 'the pond' and its a different story, alot of aftermarket and stronger bits and options for them. trimatic are a good racing box, not good for abuse. th350 cant handle much without a lot of coin on them but still got sprag issues. dont forget, the more heat/abuse an auto cops, the shorter the life they have. th400 all the way got one behind my turbo ls1. Some original photos have not been recovered yet.

From my understanding even if you throw all the best yank bits in them they still struggle especially without a full manual valve body. I assume the pathetic TV cable system is the biggest issue especially behind a forced induction car because with boost you often make a lot of torque low in the rev range and at low throttle positions especially in 3rd and 4th where there's plenty of load. Of course when your cruising in 3rd or 4th at low throttle the TV cable is only slightly pulled telling the trans to supply only moderate line pressure, problem is at low throttle high load in those gears a street setup tubo will be making lots of boost and torque and as a result burnt clutches. I spoke to a few US builders and was still steered in the TH400 direction as I didn't really need or care about the lack of overdrive. I'm curious to know if a manual valve bodied t700 is much better, personally I don't like them the most for no other reason than the stupidly short first gear and massive drop to second, in theory the 200r box could be a good unit if you spend several thousands and ran a full manual valve body, but still never as tough as the 400. I'm no auto expert by any means but that's my understanding and what made me choose my option.

what does the lock up converter do is it a needed item

It provides fuel economy. There is a guy on street commodores with a VS Manta (lol hsvtaxi) who has a tough 383 making 600hp. he is using a TH700. It can be done, but as has been mentioned, the auto's old reputation is what scares a lot of people off.

Quote: Originally Posted by mulkers [View Post] It provides fuel economy. There is a guy on street commodores with a VS Manta (lol hsvtaxi) who has a tough 383 making 600hp. he is using a TH700. It can be done, but as has been mentioned, the auto's old reputation is what scares a lot of people off. A lock up converter has a friction plate inside the converter that can lock the drive solid like a manual is, this is usually done by the computer in 3rd and 4th once the car is at a constant cruise, if you listen carefully in most cars once its in the higher gears and you stop accelerating you will almost hear like a small gear change where the revs drop a couple hundred rpm, that's the converter locking and taking any slip out from the converter. Keep in mind a converter is fluid driven and has no mechanical link usually, exception is boxes with lock up function. Its not just a economy function as on a stock low stall converter it only gains a couple hundred rpm (on a highstall especially if you have numerically low diff gears it would help more for example running a 4000 stall on a car with 3.46 diff gears in 4th would mean approx 2200 rpm at 100km/h that means the big stally would be slipping a bit as its way under stall and the oil will start to cook. If it has a lock up it goes solid and no slip means no heat. ) The t700s old rep doesn't scare me, it was 5 well known builders who said it wouldn't last as long as a 400 regardless, and it would cost more than double to build a 700 and all said it would fail behind my pissy combo and driving style and to make my choice easier that ratio difference 1st to 2nd ****s me. .

Quote: Originally Posted by mulkers [View Post] It provides fuel economy. There is a guy on street commodores with a VS Manta (lol hsvtaxi) who has a tough 383 making 600hp. he is using a TH700. It can be done, but as has been mentioned, the auto's old reputation is what scares a lot of people off. Manta 185i off there (a good mate of mine) has a vs manta with plates THRILR with a 600hp 383 aswell, using a 4l60e with 4l65e gearset and a heap of other mods. been holding up no dramas for 3yrs. Some original photos have not been recovered yet.

Quote: Originally Posted by DA HOON [View Post] Manta 185i off there (a good mate of mine) has a vs manta with plates THRILR with a 600hp 383 aswell, using a 4l60e with 4l65e gearset and a heap of other mods. been holding up no dramas for 3yrs. The E box is a completely different idea because it is controlled by the pcm it can still be set to provide reasonable road manners but also provide firm fast shifts under load, with a pre Electronic box you can either have a reasonable street box that slips and burns behind a reasonable combo or a full line pressure spine buster, I've also read of hundreds of guys in the states who say the box is fine but I say again find someone here who will back their work on a T700 and I reckon they'd have a few more customers as a lot of people actually care about economy (I'm not one). Some original photos have not been recovered yet.

Quote: Originally Posted by Nutter [View Post] A lock up converter has a friction plate inside the converter that can lock the drive solid like a manual is, this is usually done by the computer in 3rd and 4th once the car is at a constant cruise, if you listen carefully in most cars once its in the higher gears and you stop accelerating you will almost hear like a small gear change where the revs drop a couple hundred rpm, that's the converter locking and taking any slip out from the converter. Keep in mind a converter is fluid driven and has no mechanical link usually, exception is boxes with lock up function. Its not just a economy function as on a stock low stall converter it only gains a couple hundred rpm (on a highstall especially if you have numerically low diff gears it would help more for example running a 4000 stall on a car with 3.46 diff gears in 4th would mean approx 2200 rpm at 100km/h that means the big stally would be slipping a bit as its way under stall and the oil will start to cook. If it has a lock up it goes solid and no slip means no heat. ) The t700s old rep doesn't scare me, it was 5 well known builders who said it wouldn't last as long as a 400 regardless, and it would cost more than double to build a 700 and all said it would fail behind my pissy combo and driving style and to make my choice easier that ratio difference 1st to 2nd ****s me. . Are you trying to explain that to me? Where did you get this information from?

Quote: Originally Posted by mulkers [View Post] Are you trying to explain that to me? Where did you get this information from? The explanation was for the guy who asked what it does more than anyone, the info comes as I was the on the road sales rep for a melb based torque converter builder back in 2001/2002 so I spent quite a bit of time in the factory and with the transmissions shops who used us, one particular auto builder out yarra valley way was considered a jatco specialist back then and I supplied converters for quite a few vls back in those days as well as the first BA turbo factory cars for a bayswater based turbo specialist, which most people didn't know where actually C10 3 speeds with a very half assed method of extending the bolt risers amongst a few other things on that ute the general public didn't see when it started to bust in to the 10's, I also dealt with a certain wrx wagon running an svx auto holding a few records as well. I'm no expert and have been out of the converter game 10 years and out of the mechanics business for 5 years, but I still member what a lockup plate looks like and how it engages so I figured I could answer the question fairly accurately for the original poster Wkd_VL.