standard 5 speed strengthening?

[bluewagon88]

i'm gonna replace my auto sludge box with a manual 5 speed box and i'm wondering if there is a way i can strengthen the standard 5 speed to handle 500+ HP? or should i get an mx7 turbo gearbox, then renew everything in that? where would i get replacement internals from? i wanna build up a gearbox that will handle extra power but still be a bolt on job. any help would be appreciated
thanks

[Bax]

500hp? What the hell.

I'd be looking at an rb25det box, something out of an r33 skyline, these boxes are strong.

Apart from that if you want to go stronger still you can go an insanely strong manual or get a strong auto made up.

500hp just an imaginary figure?

[bluewagon88]

so where do i start looking for the parts i'd need? like motor traders or something? would you need the rb25det manual gearboxs' computer? or is that not important? and why would 500 hp be an imaginary figure? i just don't wanna spend a bucket load of money on a hypo motor and not have the drivetrain to match it.

[rb26dett]

I dont think a manual gearbox has a computer.

[Bax]

By imaginary figure I want you to be realistic. What would your motor be, what kind of power would you be expecting, and go from there?

I think alot of people over estimate on the values that they are going to have.

For 500hp I don't think much expense would be spared. So you should have no worries getting a top quality gearbox.

Try japwreckers for r33 boxes, they go for around 1200-1800, then you need a few little things like a clutch master/slave brackets or mounts, pedal box, tailshaft you can adapt i believe. a good clutch is another handful of 100's.

[slo_firo]

umm for some1 that thinks a manual needs a computer he is probably just dreaming about 500, thats alot of grunt, a 25det box should take it.... for a little while anyway

[bluewagon88]

dude i ain't dreaming, and i know that an rb30 head will flow over 600 hp without much work plus the bottom end, according to sources on this site, reckon the bottom end can handle up to 1000 hp! i've got 3 VLs sitting in my yard, 2 of which are daily drivers and the other one is my project car. before you start slagging people off for asking questions you should find out more about the person!!
anyway, what i wanna do is use the rb30 that's already in my project car (makes it easier to get roadworthy certificate, plus if you get pulled over the engine no matches your rego). i've budgetted for about $15k on the motor over a 2 year period, obviously looking at turboing it. i've got a series 2 so the block should be the same as the turbo block. before i start forking out big dollars on the motor i wanna make sure i can get a drivetrain that can handle a bit of lead footing. it'll be a weekend driver, so if i do blow something up, i don't have to worry about not having a car to get to work.
with the rb25 box is it a staight out bolt on? or are there other things that i'll need to change? and for the figures you quoted is that a reconditioned one?

[Bax]

Figures I quoted are second hand boxes + New clutch. Will bolt straight up to the engine, joys of having things from the RB series.

Apart from that little things need to be changed.

15k is that engine and driveline and body?

Engine - Good rebuild your looking at 3+
Decent turbo- say a GT35/40ish.. 2k
Stock inlet or Aftermarket, stock 40 dollars - aftermarket 600-1000
Exhaust 3" around 1k
Gearbox sorted 2.5k
Diff sorted 1k
Injectors - Fuel Pump - Reg 1k+
Management 1k+ + Tuning expenses
Intercooler and Plumbing ~ 1k
Brake upgrade.

Theres around 13k.

[rb26dett]

I wish you all the best with it.

If I can offer any advice, it would be to always purchase top quality parts. You can buy cheaper things, but they tend to break and you end up buying the better stuff in the end.

[bluewagon88]

thanks for that. apologies if i was a bit abrupt in my last reply. i had budgetted for $15k on the motor alone! but if i can do it all for that, my missus will be way pleased!! haha! at the moment i'm in the process of sourcing the interior, i figured it'd be harder to find a quality series 2 calais interior than it would be to get parts for engine and drivetrain etc. i'm sure that something like this would be an absolute pig to drive on the street, but i've always wanted a phat drag strip car, and i'm so in love with the VLs and their nissan motor that i figure you only live once!!
thanks again for your advice

[Holdfast]

Mate if you are going to do the box up where do you reckon you'll get the parts from? I recently did my MF5 up but I'd like to get a spare transmission and redo all the synchros etc.

Or can you buy a brand new box? Spose you are looking at an MX7 for your project car.

Anyway, just curious as I had problems finding parts especially C clips and roll pins for the rebuild and now being the wiser would have liked to replace a few gears etc.

Cheers

[Stewart1000]

why did you replace the roll pins?

just a tip when rebuilding a manual gearbox, if you ever loose any of the balls, chances are some balls out of your old bearings will fit perfectly... i did that with mine.

yeah get a later model skyline box, like r33, i god quoted $600 from somewhere, cant remember that was straight out of a wreck, no work done on it.

i wouldnt stick with the MF5, it wont handle 200 let alone 500!! thats an amazing figure btw!

there is not much you can do to a manual gearbox to make it stronger, use good oilm fill it to the correct level... not much you can do to the internals.

good luck with with it

[bluewagon88]

thanks for the advice guys. and yes i know 500 hp is an absolute f**k load of horse power, but i'm on a mission to destroy my mates rebuilt zj fairlne with a beefed up 351!! i can't wait for the first time we line up at the drag strip!! i'm sick of his constant bashing of anything other than a v8!! i'll definately go for the r33 box , i'm sure parts are easier to get than the vl turbo box. like i said, it's a 2 year project and i need to gather as much info as i can before i fork out wads of cash! i've now resigned to the fact that this car will probably get driven on the occasional cruise and trailered to some drag events and car shows.

[Holdfast]

why did you replace the roll pins?

Unfortunately I didn't, they were in good shape.
I wanted to put new roll pins in but I couldn't get any unless I ordered a box. Couldn't get the Circlips either except for a few thin ones, the thick ones I just couldn't get them.

[rb26dett]

Are you after 500hp at the motor or wheels?

My car has 440hp at the motor, on 15psi.

[bluewagon88]

at the motor. i know i'd be pushing it to get that at the wheels. i'd be interested to know what you did to get 440 hp. that'd probably give me a better platform to aim for

[rb26dett]

at the motor. i know i'd be pushing it to get that at the wheels. i'd be interested to know what you did to get 440 hp. that'd probably give me a better platform to aim for

T60-1 Turbo
Tial Wastegate
JPC cam ( They make about 5 different ones, this one is about 3rd on the list )
Autronic ECU
Autronic CDI
Custom exhaust manifold
Custom Plenum
Rebuilt Turbo spec bottom end
3.5" dump to cat, then 3" from cat back, it is fairly quiet because I run 2 mufflers on it.


I could have it running alot more, but im not 100% sure on what has been done to the auto, so until then I wont have it above 15psi.

If I changed the turbo to say a GT35/40 im sure it would have more power on the same boost.


With yours being manual, if you had the same set up as me, yours would make more power.

[bluewagon88]

thanks man. thats a pretty darn good output dude, did you go for larger injectors? i've heard that the rx7 series 4 & upwards are bigger but u have to make a custom fuel rail to fit it to the head. i'm sure it wouldn't be too hard if you took it to the right mechanic. did you do much to your diff and tail shaft to get it to handle your output?? or do you try to refrain from pushing your accelerator pedal thru the firewall?

[rb26dett]

Sorry, I forgot to mention that.

65lb injectors ( or about 660cc )
custom fuel rail
044 pump
4 litre surge tank.

Turbo diff will handle the power no worries at all.

You really need to treat the car with alot of respect when it has that type of power. Be prepared for anything.