Blew another SC400 transmission!!!

[jibbby]

Today my Sc400 gave up the ghost for the second time...This was a built tranny too and only one year of use...150 Nitrous shot and Lexus automatic trannies don't play well together....

Anyway, I found a 95 SC400 tranny for $350 used for a temp. swap option...Wondering if anyone knows if the 95 Sc400 tranny can be successfully and easily swapped into a 92 SC400?...Is the electrical all different?

Anyone?

 

[cribbj]

Sorry, don't have an answer to your question, but have a question for you - when you say it was a "built" tranny that you blew, do you know what the transmission rebuilder did to strengthen it? Also, have you put a transmission cooler in your setup?

Don't know if you want to spend this kind of money, but BoostLogic in Austin, TX does "built" A340E's for the Supras, and they're pretty stout. Good enough for 10-11 second quarter mile cars anyway. I have one in my black Supra, and it's pretty harsh shifting, but definitely strong - I think Ryan is using one of these in his project.

I understand that IPT who used to be site sponsor here also do built A340E's, but they're all the way on the right coast, so the freight would be a killer.

 

[Jake Breyck]

Jibby? why not a manual? or do you just not like manuals?

i dont have experance with boostlogic but if there anything like the build trans i had in my 87 auto supra they are killer, would easly handle a 1uz with a 150shot. shifting on mine was deffanatly harsh.

 

[gloverman]

It will most likely swap straight in. About the only thing that might be different is the shift switch but that can easily be swapped form your box. Cheers

 

[Lextreme II]

Jibbby,

Call me.... Today might be your lucky day.....

 

[zidaro]

Jibbby,
If your looking for another SC400 tranny in the '94 era, I got one laying around I'll sell purdy cheap. TC included.
Mammoth Lakes area and could get it to you with some arranging. PM me or call 760-914-0868 if your interested.

aaron

 

[jibbby]

Lex I will call you today....

Cribbj - Yes I am familiar with Boostlogic built trannies and I had mine built in the same fashion, clutch plates, etc... However, I did not have a tranny cooler as the builder said I wouldn't really need one with the stronger internal parts... He rated the tranny at 500whp and gave me a six month warranty... It lasted a year...

It just so happened I had blasted the car in a major way yesterday, road the nos a few times, hammered the car constantly, I guess I was just in one of those moods... Came to a stop and the tranny started slipping...Drive, reverse you name it, it would not engage.....I let it cool off and it grabbed until warm again then slipped right after... I had to tow the car home in the end... I called the builder and he blew me off because I said I upped the Nitrous shot after the tranny build... The tranny was showing signs of trouble in the past as some cold mornings start ups I did experience some slippage at times.. That was happening for a few months... So I guess this is not a total suprise to me...

I am not apposed to a manual tranny, it's just alot of work and money..I also would prefer and automatic tranny in LA traffic... Sticks get old fast in bumper to bumper traffic....

So I was thinking of a cheap temporary swap with the same year tranny... It seems when you change years the wire leads always are different like the ECU's... I am weary to get a different year tranny for my 92 SC4...I was hoping you guys know the differences between year tranny's.....

Bottom line is with over 500 torque at the wheels it's hard to keep an automatic Lex tranny, not sure boostlogic tranny's could hold up for years either...Maybe though, but I am not going to drop another 2 grand to find out...

A future manual tranny swap will be in order...R154 for V160 probably unless I get the balls to try and mate a new automatic Vette tranny or something.....

 

[cribbj]

I'm surprised your tranny builder didn't recommend or require a cooler. The two tranny builders I'm familiar with, and one torque converter builder all either recommend or require an external tranny cooler.

In fact my torque converter warranty clearly stated it would be null and void without an external cooler.

We all know that automatic trannies and torque converters lead a really tough life, and an external cooler will help them immensely.

 

[jibbby]

I hear you John....

Yes, maybe a tranny cooler would have helped matters some...I really don't know why the builder didn't recommend one as I am aware that these tranny's are definetely aided with the coolers.....I remember asking for a cooler but the builder stated that with nitrous it's just about a 5 second burst every once in a while so the tranny never gets really really hot like a boosted Lexus would. His words were a cooler isn't really necessary with my setup....That is basically what we talked about and that is why we didn't go with a cooler...

It does appear that heat caught up with my tranny as it did not break under full power but slowly gave up the ghost...So Cribbj I think you are right with your assessments..

You know these tranny's struggle to shift on time under big power, they burn out, break under 500whp, etc.. They simply just aren't made to perform over time with twice the stock power..... That's my take..

So with the next tranny I just won't hit the nitrous until I find a suitable swap option or I may just elect to strip down the car of it's mods and sell it after this feasco...Maybe I'll get a Supra TT like You John....Find one with some wasted turbo's selling for cheap and drop a 1uz-fe and boost... Sound familiar?

 

[SC400TT]

Jibby:

I am using the tranny in my project- BL built with the Billet forward clutch. I am definitely adding an external tranny cooler...Needed to protect it from excessive heat. I, too, am surprised your builder told you that no external cooler was needed...I wholeheartedly DISAGREE. Even short bursts from nitrous put tremendous stress on the tranny, and can create heat very, very quickly. IMHO, never run a modded engine (increased power and torque) on a stock tranny, or a built tranny with no cooler. Plus, even though your builder "built" your tranny, we have no way of knowing how similar his build was to BL...

The harshness of the shift was a concern to me. That is why I added the PCS controller...to help control shift harshness at different load levels and boost levels.

The project is not running yet, but I expect it to be so by End of 2007 or the beginning of 2008.

If you want to do a V160 swap, talk to Scott marshall. Now that he is into the swap, he has learned of a lot of potential issues with the swap...It is most certainly not anywhere near a "Bolt On".

Ryan

 

[Blizzy]

A trans cooler is vital for a performance car with an a/t to prevent the trans oil from getting hot enough to break down.

If you are going to reuse another stock trans, you MUST get a trans cooler, and I would strongly suggest a trans oil temp gauge as well.

The BL trans is the cheapest alternative to getting a functional transmission that will bolt up easily and hold every bit of torque that you are making. Although, even in this case, a trans cooler is a must.

I have acquired damn near every forseeable part for my R154 swap. I am in the hole ~$2200 with a lot of work and some custom fabrication ahead of me. To have found a clutch to holds 500wtq, I would be in the hole $3-400 in excess of what I am now (my clutch holds 460 crank torque). Once I am up on stands for the surgery, I expect the car to be disabled for at least a month. Regardless, I think the BL trans is a much more cost effective option to my R154 swap.

Getting a Supra TT is neither easy nor cheap, but an automatic TT is definitely going to run you less money up front. It is very difficult to find a TT for under $15k in any semblance of good condition, regardless of mileage. Swapping a 1UZ into the Supra is no small task either...especially when the money to swap in a 250hp motor could make the stock 2JZ do over 400 to the wheels.

I would hate to see you part out your SC400, since you are such a vital member of the Lextreme community. In reality, a couple grand for a BL tranny is a small price to pay to keep your SC on the road since you have put so many parts on the car as is. I definitely think you would get more value from the car by swapping a BL tranny than parting it out.

 

[1UZPWR]

Today my Sc400 gave up the ghost for the second time...This was a built tranny too and only one year of use...150 Nitrous shot and Lexus automatic trannies don't play well together....

Anyway, I found a 95 SC400 tranny for $350 used for a temp. swap option...Wondering if anyone knows if the 95 Sc400 tranny can be successfully and easily swapped into a 92 SC400?...Is the electrical all different?

Anyone?

I think where you might run into trouble, is the throttle cable for the transmission. The 92 should have one, and I think the 95 might not. If this is the case, the ECU will definitely not know what to do, and I doubt a 95 ECU would work in a 92. Check the 95 for a throttle cable.

 

[Lambo]

Hi jibbby, I guess you are not running the factory computer, because i remember reading that the factory computer retards the spark to reduce the output and so the jarring effect on the trans, it uses the kickdown switch to detect that you want to change gear and momentarly retards the spark.Maybe if you are running an aftermarket you can programe it to do something similar.

Regards
Lambo

 

[cribbj]

Maybe I'll get a Supra TT like You John....Find one with some wasted turbo's selling for cheap and drop a 1uz-fe and boost... Sound familiar?

Jibbby, have I ever got a deal for you M8. My '94 black TT Supra is for sale, and already has the BL tranny. Unfortunately (for you) the turbos are still fine, and overall it's in great condition so it ain't cheap, but contact me if you're interested.

 

[jibbby]

Jibby:

I am using the tranny in my project- BL built with the Billet forward clutch. I am definitely adding an external tranny cooler...Needed to protect it from excessive heat. I, too, am surprised your builder told you that no external cooler was needed...I wholeheartedly DISAGREE. Even short bursts from nitrous put tremendous stress on the tranny, and can create heat very, very quickly. IMHO, never run a modded engine (increased power and torque) on a stock tranny, or a built tranny with no cooler. Plus, even though your builder "built" your tranny, we have no way of knowing how similar his build was to BL...

The harshness of the shift was a concern to me. That is why I added the PCS controller...to help control shift harshness at different load levels and boost levels.

The project is not running yet, but I expect it to be so by End of 2007 or the beginning of 2008.

If you want to do a V160 swap, talk to Scott marshall. Now that he is into the swap, he has learned of a lot of potential issues with the swap...It is most certainly not anywhere near a "Bolt On".

Ryan

Ryan, Well I guess the lack of an additional transmission cooler was infact my down fall... I just called the builder to let him have it with in non cooler recommendations... He again told me the stock transimission cooling system should have been adequate for small nitrous bursts... I think even my torque converter change stall rate in my car has caused addition transmission heat too if I am not mistaken.. Hmmmm?

Just so you guys know when I built this tranny I submitted the part builds from BL as a guide line for this builder to folllow..So I think it is safe to say it was identical to a Boost logic built tranny minus the cooler... I remember the names Coleen steel and blue asbestos something or other as the main components in the upgrade... I am not a tranny expert and can't even remember the name of the parts involved...

Oh, and also the PCS controller equiped with your boost logic transmission is a very good idea.. Anything to help with the shifts is a good idea on these trannies..

 

[jibbby]

A trans cooler is vital for a performance car with an a/t to prevent the trans oil from getting hot enough to break down.

If you are going to reuse another stock trans, you MUST get a trans cooler, and I would strongly suggest a trans oil temp gauge as well.

The BL trans is the cheapest alternative to getting a functional transmission that will bolt up easily and hold every bit of torque that you are making. Although, even in this case, a trans cooler is a must.

I have acquired damn near every forseeable part for my R154 swap. I am in the hole ~$2200 with a lot of work and some custom fabrication ahead of me. To have found a clutch to holds 500wtq, I would be in the hole $3-400 in excess of what I am now (my clutch holds 460 crank torque). Once I am up on stands for the surgery, I expect the car to be disabled for at least a month. Regardless, I think the BL trans is a much more cost effective option to my R154 swap.

Getting a Supra TT is neither easy nor cheap, but an automatic TT is definitely going to run you less money up front. It is very difficult to find a TT for under $15k in any semblance of good condition, regardless of mileage. Swapping a 1UZ into the Supra is no small task either...especially when the money to swap in a 250hp motor could make the stock 2JZ do over 400 to the wheels.

I would hate to see you part out your SC400, since you are such a vital member of the Lextreme community. In reality, a couple grand for a BL tranny is a small price to pay to keep your SC on the road since you have put so many parts on the car as is. I definitely think you would get more value from the car by swapping a BL tranny than parting it out.

Blizzy, I am fully aware of "ALL" the work involved in these SC400 manual tranny swaps... That is why I haven't done it yet, too much money and too much work.... The V160 swap can run you as much as 10 grand when it is all said and done... Ouch!!!

Also thanks for considering me as a vital member of the Lexus Community..I never thought of me in that light, I just like all this crap and posting on the forum with you guys...

 

[jibbby]

I think where you might run into trouble, is the throttle cable for the transmission. The 92 should have one, and I think the 95 might not. If this is the case, the ECU will definitely not know what to do, and I doubt a 95 ECU would work in a 92. Check the 95 for a throttle cable.

The 95 does have the throttle cable like the 92.. I will stick with the same year tranny for swap thanks... And yes the ECU from every different year model SC will not work, I have tried... The electric pins change from year to year... I bought a 94 and 95 ECU years back and neither would fit correctly on my 92 SC.... Trannies I would venture to guess may pose the same problem...

 

[jibbby]

Hi jibbby, I guess you are not running the factory computer, because i remember reading that the factory computer retards the spark to reduce the output and so the jarring effect on the trans, it uses the kickdown switch to detect that you want to change gear and momentarly retards the spark.Maybe if you are running an aftermarket you can programe it to do something similar.

Regards
Lambo

Hey Lambo... I am currently using one of those Apexi SAFC-II piggyback ecu's... I can tweak the fuel mix but not the timing...

With both my trannies it was case about half the time when running the nitrous the shifts were late or not at all.. Second gear especially.. Sometimes third... I would have to lay off the throttle at times just for a split second to allow the tranny to shift down....Most disturbing during a race situation to say the least...This only occured under the nitrous runs... Both trannies built and non built...

 

[jibbby]

Jibbby, have I ever got a deal for you M8. My '94 black TT Supra is for sale, and already has the BL tranny. Unfortunately (for you) the turbos are still fine, and overall it's in great condition so it ain't cheap, but contact me if you're interested.

Thanks Cribbj, but I said a beat up TT supra with wasted turbo's for cheap, not a clean black one that probably looks and runs perfect for bank....

Curious, why must you sell?

 

[Lextreme II]

Jibbby has money... he is single.....LOL.....