what's the max bhp the autobox can support?

 

is it around 350 - 400 before having to alter?

The autobox is the 300zx achillies heel. Enough of them die on a regular basis with stock power.

Edited April 14, 200916 yr by Yowser

ok . so what am i looking at for a decent replacement that can handle 400-450bhp? i would go manual but the mrs drives and loves the auto when poodling

so more answers to this? sorry to bring an old thread but i would like to see what "AUTO" gearbox i would need (or what i could do to mine) to get it to handle up to 500bhp?

 

would i need to buy a different auto box or get away with just rebuilding mine?

The autobox is the 300zx achillies heel. Enough of them die on a regular basis with stock power.

 

Sticking point that, there are people on here who think the Manual is weeker than the Auto in regards to power handling capabilities. :duffer:

If you have a sound box and big power then the least mod that should be done is a decent cooler for the fluid. On normalish power at least from the experience of my car - 140K was done before the box eventually expired and that was only with the water pipe in the rad type cooler. If you are going to do repeated full bore standing 1/4 miles then all boxes will eventually give in.

cool. thanks for the info. i may only go to 400 - 450bhp because it will be a daily driver

 

I will look into the oil cooler for my box anyway though :-)

People have had autoboxes rebuilt to handle more power in the past. They fit stronger bands for improved reliability and increase the line pressure for quicker changes (there may be other changes too).

 

Sticking point that, there are people on here who think the Manual is weeker than the Auto in regards to power handling capabilities. :duffer:

 

:rofl: Nobody surely thinks that about a stock autobox, cant say I've ever seen anything that ridiculous said by another member before !?

Edited May 22, 200916 yr by Yowser

:rofl: Nobody surely thinks that about a stock autobox, cant say I've ever seen anything that ridiculous said by another member before !?

 

Who said stock? Same as no one is saying stock clutches for the manual box ;)

Who said stock? Same as no one is saying stock clutches for the manual box ;)

 

erm....your reply was to my comments about the weak stock autobox.

 

You cant argue with my comments about the Nissan autobox and then claim your not even talking about the Nissan autobox anyway LOL

 

..and a Manual Clutch is entirely different thing to an entire gearbox

Edited May 23, 200916 yr by Yowser

erm....your reply was to my comments about the weak stock autobox.

 

You cant argue with my comments about the Nissan autobox and then claim your not even talking about the Nissan autobox anyway LOL

 

..and a Manual Clutch is entirely different thing to an entire gearbox

 

:headvswal

 

The guy was asking about capabilities, not about the factory stock. And it is an agument point that the auto box is CAPABLE of holding more power than the manual (where is macca when you need him).

 

BOTH will need to be uprated if your running more than stock boost so why would I be refering to a stock box when talking about uprated power?

:headvswal

 

The guy was asking about capabilities, not about the factory stock. And it is an agument point that the auto box is CAPABLE of holding more power than the manual (where is macca when you need him).

 

BOTH will need to be uprated if your running more than stock boost so why would I be refering to a stock box when talking about uprated power?

LOL You can bang you head against a wall and then back pedal as much as you like but I quite clearly said the Autobox is the 300zx weak point, you argued its not, and then later claimed it must be uprated first :rofl:

 

The Manual box does not need to be uprated to handle more power than stock, the Autobox does, they die regularly enough on stock power.

 

As to how much power an updated fastroad box can handle, no idea, there had only ever been a couple in the UK and none of them have been particularity high power.

 

Rebuilding an Autobox to make it handle more power is not the same as replacing a clutch. :rolleyes: Replacing the Torque convertor would be a comparative.

 

Plus rebuilding the Autobox into a Fastroad box to handle more power still isn't going to allow it handle serious power like all the manual boxes out there, the only high powered Auto's out there are ones running dedicated 3-speed drag boxes that you wouldn't actually use on the road.

 

I have removed and scrapped enough Z autoboxes over the years to be able to comfortably say they are most definatly the weakest point of a 300zx.

Edited May 23, 200916 yr by Yowser

Please mines an auto so stop keep upsetting me. I love the auto box :hyper:

You can uprate the valve body (big flat plate thing) in the bottom of the box and they can take aaround the 500 mark..

thats very handy to know :-) i will look into doing that when fitting my uprated oil cooler

LOL You can bang you head against a wall and then back pedal as much as you like but I quite clearly said the Autobox is the 300zx weak point, you argued its not, and then later claimed it must be uprated first :rofl:

 

I have not argued once about it being a week point???? I have argued from the start that there are people who think the auto is capable of higher BHP than a manual, Which it is! I have not back peaddled once I have completely stayed with exactly what I first stated

there are people on here who think the Manual is weeker than the Auto in regards to power handling capabilities. :duffer:

 

 

The Manual box does not need to be uprated to handle more power than stock,

 

Well thats complete shit, no none with upped boost lasts more than 1000 miles untill the stock clutch needs upgrading (remember YOU are refering to stock here). And please dont say a clutch is not part of a manual box again :rofl:

 

 

The Autobox does, they die regularly enough on stock power.

 

Yes they do, at no point have I said they dont. Again and I will say this slowly so you can grasp it

there are people on here who think the Manual is weeker than the Auto in regards to power handling capabilities. :duffer:

 

 

Rebuilding an Autobox to make it handle more power is not the same as replacing a clutch.

 

Replacing the drivetrain internals to uprated ones to handle bigger power??? Sounds exactly the same to me! :duffer:

 

 

Plus rebuilding the Autobox into a Fastroad box to handle more power still isn't going to allow it handle serious power like all the manual boxes out there, the only high powered Auto's out there are ones running dedicated 3-speed drag boxes that you wouldn't actually use on the road.

 

Again I'd like to see Ian's (MAC 1) comments on that as he is always saying how shite the manual is and cant handle the power and wishes he had the fast road auto box back. Hence my original coment, are we ready???

there are people on here who think the Manual is weeker than the Auto in regards to power handling capabilities. :duffer:

 

I have removed and scrapped enough Z autoboxes over the years to be able to comfortably say they are most definatly the weakest point of a 300zx.

 

See again your having trouble stying on topic and not going off on your own funny little tangent. Let me say it one more time in the vain effort of you maybe grasping what I'm saying. And this is the same as ever, there is no back peddling its the same statement

there are people on here who think the Manual is weeker than the Auto in regards to power handling capabilities. :duffer:

 

I think we have argued this one to death now, and I've enjoyed every second of it. Mostly because you dont seam to read my posts and reply with stuff about nothing to do with what I've written :rofl:

If you think that rebuilding an Autobox to make it into a fastroad box (which still has unknown power handing capablities) is the same as replacing a clutch then fine. :rolleyes:

 

Maybe your not familiar with Drivetrain mechanics, but a clutch is not Drivetrain internals. It is external to the box, just like a torque convertor. it sits in the Open ended Bellhousing of the gearbox.

 

You get uprated torque convertors too with higher stall limits, replacing either a TQ or a Clutch is not the same as rebuilding a gearbox.

Edited May 24, 200916 yr by Yowser

There aint many Z's around that need to uprate the manual box for power, except the clutch.

You can uprate the valve body (big flat plate thing) in the bottom of the box and they can take aaround the 500 mark..

 

That's very interesting ...is it easy/expensive to do?