Aftermarket gear set failures???

V

velly4

Member
Ok guys I curios to know exact details of who, what, why and where those with aftermarket gear sets have failed or split gearbox cases.
I've also posted this on the Oz forum.

I want to know what you were doing, drags, motorsport event, the type of surface you were on, what clutch, how much RPM when launched, boost when launched and any other detail that may have contributed.

I currently have my car set up to launch at about 4200rpm with about 7-8psi boost.


Here's a template


Type of event/on the street:
Surface:
Clutch/flywheel:
What tyres:
Type & Brand of gear set:
RPM at launch:
Boost:
How did you launch it: Side step the clutch or slip it?
Who built the gear box:
Year model of the gearbox casing if known:
How long you had been running the aftermarket gear set:
What exactly failed:
 
Fast Guy

Fast Guy

Moderators
Staff member
I take it you have launch control. 4200rpm is quite low for launching, does the rpm drop much below that when you let the clutch out?. Do you have any traction problems off the line or does it bog down?
I normally launch at much higher rpm, but will be surprised if I'm making that amount of boost. (what turbo are you on)

I am still on my standard gear box, but I filled your template in just for a comparison for you.
velly4 said:
I currently have my car set up to launch at about 4200rpm with about 7-8psi boost.




Type of event/on the street: rwyb
Surface: tarmac/concrete
Clutch/flywheel:cyn-r-gy/rps max street
What tyres:dunlop sp sport 9000s 215/35/16
Type & Brand of gear set: standard
RPM at launch:5500-6000+
Boost:standard
How did you launch it: Side step the clutch or slip it? neither let it up quickly whilst planting the throttle
Who built the gear box: Nissan
Year model of the gearbox casing if known: standard RB
How long you had been running the aftermarket gear set: I'm not, still standard after 8.5years
What exactly failed:Nothing
Click to expand...
 
V

velly4

Member
I have only launched my car in anger before I done the rebuild and the rest of the work. I only ever launch my car during a timed event.
I found around 5000 was a good launch point for my car at the time, but it wasn't building 8psi at launch then.

Yes I have launch control now, I'm running a Vipec ECU. It was set at that amount due to a fellow Oz owner running an Autronic ECU had his set around the same and found it lunched fine. I haven't tested mine at that value yet as the anti lag is causing a few issues.

To me it seems most (in Oz anyway) aftermarket failures have been cars used on the drag strip with a high grip surface.

There are a few of us atm playing with ideas on which is the best approach to take with gear sets hence this thread.
So if it turns out its mainly those doing drags that are having problems I'm going to run an aftermarket set and not worry about it too much as dragging doesn't interest me it to
 
N

nismoboy

New Member
If your not going to launch the car and keep the power under 320hp the stock box will be fine if it in gd condition and u shift sympatheticly. If going above this power (still dont launch) i`d` suggest a quaiffe gear set and some extra bracing/welding to the case job done.

If drag racing is your thing and u want big power and full bore launching, You`ll need dog box a with straight cut final drive and extreme welding and bracing in the right areas or even better a custom casing.
 
red reading

red reading

Active Member
nismoboy said:
If your not going to launch the car and keep the power under 320hp the stock box will be fine if it in gd condition and u shift sympatheticly. If going above this power (still dont launch) i`d` suggest a quaiffe gear set and some extra bracing/welding to the case job done.

If drag racing is your thing and u want big power and full bore launching, You`ll need dog box a with straight cut final drive and extreme welding and bracing in the right areas or even better a custom casing.
Click to expand...
It's not quite as simple as welding a few plates in the right places............
 
PobodY

PobodY

Moderators
Staff member
nismoboy said:
Ii`d` suggest a quaiffe gear set and some extra bracing/welding to the case job done.
Click to expand...
Given he's already in Australia, I'd suggest that PAR might be a more sensible choice. - I'm pretty sure they make a straight-cut set which would help.
 
V

velly4

Member
I well aware of my options for gear sets. The idea of this thread is to try and get a bit of info together in one place regarding what failures have happened with what gear set and see what kind of common causes there are.

In Oz I only know of PAR sets splitting cases, haven't seen or heard of a PPG set doing the same.
 
N

nismoboy

New Member
They have split open with just about every gear set in them, its just a major weak spot on the pulsar. Ive seen broken cases with quaife, ppg,par and even one with a standard gearset.
 
red reading

red reading

Active Member
velly4 said:
I well aware of my options for gear sets. The idea of this thread is to try and get a bit of info together in one place regarding what failures have happened with what gear set and see what kind of common causes there are.

In Oz I only know of PAR sets splitting cases, haven't seen or heard of a PPG set doing the same.
Click to expand...
The coomon causes are,launching the car,twin plate clutch,helical final drive,slick/semi slick tyres, i have looked at these very in depth............. after a certain point it becomes very expensive to build a bullet proof box prices below (rough uk prices)

ppg gearset 1-4th £5500
ppg final drive £1300
Billet selector forks £300
cuff to replace 5th gear £300
brace'd cases £1000
cryo everything £250
shotpeen everything £250
Bearing conversion £200
Sudries and build cost £500

£10,000 to build a proper gearbox, yikes..................and guess what i'm building...lol
 
Fast Guy

Fast Guy

Moderators
Staff member
Will it still hold though? Sometimes I wonder if a new gearcase would make more sense. Have you done any more on that?


Was there much damage to Simons ppg geaset when the case went?
 
red reading

red reading

Active Member
It'll hold, this is the gearcases i have have been doing carl and as for simons ppg...............every gear is broken or damaged.

To get new gear box cases designed and cast would cost about £10,000 per set for 10 sets or about £100k, you could go billet cnc and just thicken them up in the right places but just for half of the pair of gear cases you would be looking at £5k, my way off basically re-manufacture is about the cheapest to date...........

Time has been my biggest problem of late tbh, but i will be back on track with it all soon


Fast Guy said:
Will it still hold though? Sometimes I wonder if a new gearcase would make more sense. Have you done any more on that?


Was there much damage to Simons ppg geaset when the case went?
Click to expand...
 
STU666V

STU666V

Active Member
Would it not be easier and cheaper to convert a decent box to fit the pulsar? Evo?

Standard evo boxes are good. Well a lot better than the pulsar.

10K for a gear box!! Thats a lot of cash.
 
red reading

red reading

Active Member
STU666V said:
Would it not be easier and cheaper to convert a decent box to fit the pulsar? Evo?

Standard evo boxes are good. Well a lot better than the pulsar.

10K for a gear box!! Thats a lot of cash.
Click to expand...
It's not really alot for a gearbox at all, specially not a aftermarket one, and only a certain evo gearbox is better than a pulsar,they also have weak transfer boxes and weak ayc rear diff's............but they just spend the money and get better aftermarket ones, where as most pulsar owners won't spend the money.
 
red reading

red reading

Active Member
Also forgot i have a nismo diff to go in mine too........ how do you price that i reckon it must be £1400, all the prices i put up are for new parts too in my previous post, and remember you only need something as heavily modified as that if you want to run alot of power and drag race it.
 
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