I have heard if you Turbo your car and have an automatic tranny that most people will give it say....2 weeks before your auto will **** out on you. WHAT EXACTLY on the transmission is braking because I also noticed in the FAQ section that upgrading the valve body was a good idea....sooo would this HELP prevent the crapping of an auto?


just wondering.

 

Best thing to do to prevent your auto crapping out is doing a 5sp swap.

 

Well, one factor is heat. A tranny cooler will help a great deal. That won't magically make your auto able to withstand the increased power, though.

 

From a 125-shot nitrous user, these things will help:

1. Do DR-mod to tranny, so WOT = full internal pressure = less slippage.

2. Install healthy tranny oil cooler - I use a 16KVW B&M up front.

3. Switch to Mobil1 oil.


I have used the same automatic for two years, street and strip, and it shifts the same now as it did when I installed it. And with the Shift_Fast mod, it shifts really fast, too. Spins the M&H slicks going into 3rd gear.

 

Not 2 weeks but it will definitely shorten the life of your auto tranny. Same goes for the S/C.

 

You guys need to find out what Jime does to his autos to get them to hold up. I know alot above manual transmissions but not about autos so I can't give any real info other than upping the line pressure to prevent slippage like grey99 said, but Jime has been abusing his auto transmissions from day one and never had a failure to my knowledge. Maybe what grey99 posted is what jime did to his - but whatever it is you guys need to ask him.

 

Jime does the same thing Grey99max does and the same thing I do to my auto. Mobil 1 ATF is a MUST, tranny cooler is a must, and drop resistor is a must. Here is my theory:

The reason Jime and gray99 or myself have not blown our transmission is probably because we ofcourse use the drop resistor (the key to keeping it from dying). The thing is, jime and gray99 run at the track where there is no downshifting involved. If gray99, jime, or myself drive aroudn the city flooring it from a roll, then our tranny will probably die very very quickly. reason being is that when the car downshifts there is alot of slippage and alot of heat buildup thats why alot of poeple have broken their auto while attempting to spray while the car was downshifting. Now since dr mod is best for when you are at WOT, the other option for city driving with a boosted auto is VB mod, with VB upgraded it has the hard instant shift all the time. so even during downshifts it still shifts quick enought to lessen the slippage and heat. so the question is, will you be boosting to drive your car hard in the city/highway. or will you be boosting for the track only? if u going to do it for the track only where you wont see any downshifting, then do Drop resistor. if your going to be driving hard city/highway then do VB upgrade. although i still belive that drop resistor actually is more beneficial (at the track) than vb. but no actual proof of anything i have said, just my common sense i guess. hope this helps.

 

Couldn't have said it better.

 

Is it possible to do the DR and VB mods or are they mutually exclusive?

 

Its possible, so you can then have faster part throttle shifts utilizing the VB mod and the DR will then give you full line pressure at WOT. Probably if you got a highly modified VB then you wouldn't need the DR mod. However I like the way mine shifts at part throttle and only want full pressure at WOT. Good thing we don't all like the same things or I would have to race against all Maxima's and never get a chance to kick some Stang GT, Camaro etc butt.

Hey Neal you thinkin bout gettin an auto?

 

Has anyone used the shift kits on this page? http://www.txchange.com/sk.htm

 

Dang, I think the kid's catching on..... lol j/k .... Hey streetzlegend, have you had a chance to smoke those slicks yet?

For what it's worth, I turn on my DR-mod at the strip and leave the pressure boosted all the time - it seems to make a difference in how "crisp" the tranny shifts that way. With the Shift_Fast mod running the show, shifting is fantastic. I like it.

 

haha, well i have asked you and jime so much that iv become a master with this auto thing LOL.

havnt had the chance to test the slicks yet, I am goign to be tuning soon, have a bid for a vafc2 and also need to change motor mounts before i spray again otherwise my engine is goign to probably fly through the hood lol.

 

Good to see someone else "coming up" using an automatic tranny. Jime helped me through the early stages of DR-modding, then keeps coming up with new things - it's hard to keep up. I like it - what's life without some challenges, right? And we learn from each other... I especially like my Shift_Fast mod.

If the rain holds off in Kansas City on Friday, I'm going back out again with a 150-shot combo spray. I was having problems when engaging the second stage of nitrous - car would stumble, drop power - and it turned out to be the old battery! It couldn't deliver enough current to power the second pair of solenoids while running the bottle heater and the first-stage pair. A new 800-amp battery cured that problem.

I've also been using a 10-15 volts-in DC-DC voltage converter to boost my ignition coils from battery voltage to a switchable voltage (15-16-18-19-20-21-22-24 volt out). They're cheap - about $50 - and can be connected at one wire on a connector to run all six coils. I've been driving - and spraying on the street - at 16 volts with no problems. I'm determined to open my spark gap back up from .030 to .040 or higher. Something new for Friday.... Maintain.

Power supply (PST-P90W):
http://www.powerstream.com/dc6.htm

 

goodluck when u go back.

are you using the converter so that you can try and control or keep engine from hitting rev limiter?

 

My version of the Shift_Fast mod is controlled by a 8969 MSD RPM switch, so I set the MSD to whatever and my version will then shift the 1-2 and 2-3 shifts at the programmed RPM - so yes, I use it to keep under the fuel-cut point. The highest I've set it to shift was 6300, which worked fine, but I was having those problems with the nitrous second stage, so never went higher. Maybe Friday - with a 75-shot + 75-shot, and the Shift_Fast, it should be interesting....

 

Just remember that under more power, the tranny always slips a lil more. so try not to get too close to the cut when shifting. You dont want it to slip into the fuel cut and hurt something. Maybe you can some how rig up the msd switch you have to not only make it shift but also stop the nitrous or get a seperate switch to stop nitrous at like 6400 or right before the cut. that way you dont have to worry about ever touching the cut with nitrous still sprayin. with my MSD I have a 6100 pill so that it stops spraying right before the shift. You would think that not spraying inbetween shift would slow you down, but at the track i tested with the nitrous cut at 6100, and also with nitrous spraying while shifting, and i had nooo gain wats so ever. in fact i ran the exact same time, in trap speed, 1/4 time, and 60'.

 

Actually - I have found that if I leave the DR-mod switched on all the time, I don't have slippage on either the 1-2 or 2-3 shifts. The slicks just scream when the tranny shifts with a bang. You would think it was a manual tranny.

I did the window-switch thing years ago - part of the reason I have four 8969 MSDs, but I didn't see the point. Now I can program my Shift_Fast to shift where I want it to, so I feel comfortable with that right now. Interlocking the two might be an additional safety factor, but........

Did you find that what you did gave you a better 1-2 shift? And have you tried leaving the DR-mod switch open while at the track?? Not just at WOT, but all the time. I would never drive on the street like that, but at the track, it seems to work OK.

 

I am planning to leave it open when i go back to the track, i wonder if jime has it open all the time as well or just wot. I havent tested it yet on the street either, so i shall give it a try. lately on n/a runs i have been chrippin tire a lil bit on my 1-2shift, don kno why. i THINK so far the times that is has done is is when the temperature of tranny was at around 150ish degree so that means it shifts harder(or quicker i think) when cooler, i just dont kno if its safe. when its at 180degree's (how it usually is) it dosnt chirp.

Jime if u read this, do you think runnin a larger cooler might cause some problems. i dont think i will be overcoolin it here in miami (uber hot). and my gauge reads after the cooler so its actually hotter than wat i see. maybe i can somehow rig u a fan to it.

 

So far I just have it on the WOT switch but I really don't think it does anything with the shift fast mod. I don't think you can overcool it for racing, I leave my rad and trans fans on all the time at full speed at the track. Also 180 is pretty safe, the v8 guys I know run 220+ with their hi stall converters and they aren't using synthetic fluid either.

I run my fans after each run when I shut the car off to cool everything down. I am running a 5/8 orifice vs a thermostat in the rad so it circulates naturally without having a pump. The atf does not circulate though so I start it occasionally to circulate it and help in cooling the trans.

 

From reading all this it sounds like I'm pretty much on the right track. I have my tranny cooler just havent installed it yet and I have my dr mod working but I dont have the mobil 1. I'm at 140000+ miles so its to late to switch from what i've read. I turn my dr mod off and switch my fans on at the end of each run. I try to leave my fans on as long as possible but I'm afraid they will drain the battery so i turn my car on and let it run for maybe a minute or so. I'll be going to the track again soon hopefully i'll have my tranny cooler on by then.

 

where can I get the vb upgrade??

 

Woops - I just re-read your message - I missed this part.

No, the DC to DC converter is used to Raise the nominal 12 volts from the battery to a switchable higher voltage that goes to all six coils. This Raises the spark voltage at each coil. Rumor is that you lose - or gain - 10,000 volts at the plug for every volt changed at the ignition coil.

In our 4th gen Maxes, all the coils have a common power wire that come to a single connector as one wire. I can easily insert the DC to DC converter at that point, and select the voltage going to all the coils from 15 volts to 24 volts.

Supposedly, the spark voltage will go up when the coil voltage goes up. I have to gap my plugs down to .030 to keep pulling through the traps, and with today's 150-shot testing, I bet that .030 would be a problem, so I'm raising the coil voltage from 14 volts to 16 volts. So far, so good on the street....

Today's trip to KCIR should be exciting. I'll be running a 75-shot + 75-shot combination, M&H slicks, the MSD-controlled Shift_Fast shifter, and 16 volts on the coils. Something's gotta go wrong, but I'm hoping for good ETs.

If everythings keeps working, maybe I can try a 100-shot + 75-shot combination as the grand finale! Maybe...

 

and what is this msd shift fast mod?

 

x2, it's the only thing holding me back from picking up a max to turbocharge................

 

This is going to sound crazy, but unless you LOVE Maximas, go for something else if you have plans to turbo right off the bat. There are way better platforms for it.

DISCLAIMER: I would turbo my Max in a heartbeat, but it's only because I LOVE them and already have one.

 

I am running 2 B&M tranny coolers to take advandage of as much colling as possible.


Close up of both coolers



with the bumper cover on it.

 

Nice, but remember, over cooling it is not a good thing either.

 

Rob from HRH was the one that told me to do it that way. With the higher stall converter and the posi gear box he said it would be best... it was cheaper thatn getting a custom tranny cooler.

 

posi gear box. can u tell me lil more about this? or u refering to LSD?

 

Not only is that a fantastic-looking Max, but you have a resident daemon in the center of your radiators!!!

Sorry - it jumped out at me when I read your post. Do you track that monster, and if so, how does it perform????

 

I remember some using a Line Pressure Controller for the TT 300ZXs some years back, kindof like an adjustable VB (all had a high stall TC but no idea if they used a beefed up VB)...

Has anyone ever checked into one of those? I'd considered using one on my old '93 Altima auto when I was working on adding FI to it...

Just a thought...

For street use, I'd get the upgraded tranny cooler, VB job and then perhaps the higher stall TC if you're going to track it possibly...

Jeremy

 

http://www.conceptzperformance.com/C...5967.163.67.66

^ That thing? Why bother when we understand how ours work and already know how to control it with parts from Radio Shack?

 

No, not LSD. The gear box on my tranny is larger because Rob makes new gears so that it is an actual posi def. Hell the drive shat is even re-machined for the setup. Very nice for traction

Is the resident daemon the FMIC? I am sorry that I have no idea what that is... explain

 

Nope, he's referring to that bracket right in the very middle that your horn is bolted to. Look in the VERY center of the picture he quoted. Personally, I think it kind of looks like one of the Transformers symbols

 

Oh, I get it know... long day at work. I am a little brain dead hehehe


Have not been to the track, since the latest setup, but I am hoping to make it in the next month before thing close down over here.

 

Ok Tatanko, enlighten me please....is it nothing more than a $300 DR mod or something? Is it only good for drag strip, WOT (like DR) shifts or all around driving, like full throttle downshifting,etc...?

I'm going to be doing a VB upgrade in the near future (not sure what brand) and had wondered if the line pressure controller was even worth it if I could find it used on ebay or something..

Thanks!

Jeremy

 

it IS a $300 DR mod.

 

^ What he said.

It IS more than our DR mod, as this is supposedly variable, and ours is pretty much on/off. But, why would you want anything other than comfort/race? What use would you have for anything in between?

 

Well, since the DR mod is really only best used when racing I was just wondering if the Line Pressure Controller was a decent alternative to a VB job, basically, if it was an electronic equivalent...I'm pretty hard on my auto which includes a lot of full throttle kickdowns so I want something that will firm up the shifts where up or downshifting...

Thanks guys

Jeremy