Jump to content
SAU Community

Recommended Posts

i have been speaking to ben over the last couple of weeks, and he has told me not one circuit gtr has blown one, only dick heads who smash the limiter,

i was guna but the gears offered in the group buy, but i dont really wanna be a guinea pig,

he told me any pump will break the gears if the the moron behind the wheel smashes the limiter,

ben has advised me to get a tomei pump if i want piece of mind

even he hasnt heard of a tomei pump breaking

Still awaiting a reply in the group buy topic. Without any form of answer to the questions being asked i'm not very confident on buying considering these will be the first lot for testing.

Id feel much more confident if they were made of 4340 not that 4140 is rubbish but why not go for the best? impact and tensile tests IMO are a must on a test piece of steel that has been tempered to the specifications used in this gearset/collar.

On a side note who was it that got the standard gears tested for hardness??? Did it get done?

So, ive been following this thread with interest and have a couple of thoughts and idea's.

So far limiter bashing has been the main reason for smashed gears in the pump, what if you could back the timming right off before the limiter? One would assume that it will help the cause?

Asking this as Im building a rb30 for drift use, I dont plan on holding it on the limiter, but hitting it is something that I cant really control.

Cheers,

how can you call a person a dick head for hitting limiter when most drifters will tell you its a must

you cant just up shift when you want to extend a slide sometimes

if you want an easy fix go external pump

As good as these splined gears sound..until they are proven i wont be jumping in as a guinea pig.

Get some testing done first (like other guys have already asked for) before subjecting everyone to a product that could be an epic fail as dIrtgarage said.

I would rather the reinik gears..atleast they are proven

As good as these splined gears sound..until they are proven i wont be jumping in as a guinea pig.

Get some testing done first (like other guys have already asked for) before subjecting everyone to a product that could be an epic fail as dIrtgarage said.

I would rather the reinik gears..atleast they are proven

Nitto pumps can eat engine parts...and still live.

Ive seen one eat...it was amazing.

Their gear material is the best of any pumps/gearset's on the market...period. Parent material from Sweden...machined in Germany...no contest. The only OEM style pump i would use or recommend.

Edited by DiRTgarage
Nitto pumps can eat engine parts...and still live.

Ive seen one eat...it was amazing.

Their gear material is the best of any pumps/gearset's on the market...period. Parent material from Sweden...machined in Germany...no contest. The only OEM style pump i would use or recommend.

That is bloody insane!

We use a small VW oil pump on one of our drill heads at work, as soon as a tiny bit of metal (from a shat bearing) went through the pump, the shaft snapped instantly.

Nitto pumps can eat engine parts...and still live.

Ive seen one eat...it was amazing.

Their gear material is the best of any pumps/gearset's on the market...period. Parent material from Sweden...machined in Germany...no contest. The only OEM style pump i would use or recommend.

i can attest to the above comment, ive also witnessed this metal eating pump.

lots of drifters smash limiters without breaking pumps, i don't think you can assume that limiter bashing breaks pumps.

i am the biggest moron limiter basher you will find. so far only killed 1 x N1 and i suspect it ate turbo bearing anyway. Or it could have been just me being a moron smashing it at 9500rpm. :P

someone needs to make a crank collar with a corse 6 or 8 spline drive and a oil pump to suit. aka all toyota inlne 6.. i havent really heard much of 1 and 2j engines with oil pump problems.

it will work.

a good example is the v8 ute series engines i work on, the modular ford v8 5.4 quad cam. smashes oil pumps very easily and has the same square drive as our rb engine. we had to get custom steel gears made, but still have the oil pump problem, insted of them cracking they bend and gall up..

where as the ls1 and newer 6.0L has the multi spline drive oil pump. never seen one break in a ute with over 4 years of racing. and they are a powder metal drive with sinterd oil pump gears.

The flat drive is a bad design especially when you look at the gears and see how little the wall of material is left on the gears.

The more splines the better because as the number of splines increases the surface area increases and the size of the tooth decreases which means the overall minimum thickness of the gear has increased (stronger). Even the smallest amounts can make all the difference.

here is a quick example i did for work:

'x' shear pin with a 15mm diameter produced a UTS shear loading capacity of 4.3 metric tons

the revised sheer pin is 19mm in diameter and made of the same material which holds a max of 6.9 metric tons

Now if you look at these gears (posted earlier) you can see how thick the gear teeth are but how small the minium thickness of the gear is. And where did it shear? in between each tooth. If that had lots of small teeth the minimum thickness could be doubled or tripled easily.

post-41232-1252544380_thumb.jpg

The next problem is of course heat. You will all have seen the tiny splines (like on a three piece crank of a cycle) they are very small, maybe 1mm at the base of the tooth max but teeth like these would be no good in an engine as the smaller the teeth the smaller the components tolerances must be. That's why the toyota design is a win because they have done all the work for us and we just need to copy it! perfect. Not sure how many teeth they have but the 2jz has allot more than 8.

The last problem is getting the material correct, and that's it. which is why i insist we go through the testing process! If they have readily access to 4140 and 4340 then go the 4340 it makes all the sense as 4340 is better at withstanding shock (like that of limiter bashing)

didn't get time to proof read this i gotta run. hope it makes sense.

Edited by GT-RZ
someone needs to make a crank collar with a corse 6 or 8 spline drive and a oil pump to suit. aka all toyota inlne 6.. i havent really heard much of 1 and 2j engines with oil pump problems.

it will work.

It's already happening, I guess I'm going to be one of the guinea cops!

Still awaiting a reply in the group buy topic. Without any form of answer to the questions being asked i'm not very confident on buying considering these will be the first lot for testing.

Id feel much more confident if they were made of 4340 not that 4140 is rubbish but why not go for the best? impact and tensile tests IMO are a must on a test piece of steel that has been tempered to the specifications used in this gearset/collar.

On a side note who was it that got the standard gears tested for hardness??? Did it get done?

4140 is a good material for the gears. I spoke to the heat treaters who recommended it over 4340 because although the 4140 doesn't end up as hard, it will not be as brittle. Hardness isn't as critical as toughness for the gears as they are very well lubricated and wear isn't a big issue. Cost wise there's very little difference. If you weren't going to harden the gears you'd use en26 or similar.

Both can be treated to the same tensile strength. then it's the impact resistance that sets them apart. good info below:

There is a huge difference between these two alloys chemically, namely the nickel content: 4140 nominally has no Ni and 4340 contains between 1.65 and 2.00 % Ni. This contributes to substantial differences in hardenability and fracture toughness, and also has a positive effect on distortion during quenching and corrosion resistance. As a surrogate for K1c values, I'll use Izod impact energy as a comparison of the relative toughness of these two alloys:

-------------------------------------------------4140 / 4340

tensile strength in MPa ----------------------impact energy in Joules

~1965 MPa (tempered @205C) ---------------------15 / 20

~1720 MPa (tempered @315C)---------------------- 9 / 14

~1020 MPa (tempered @595/650)------------------ 93 / 100

This data is for room temperature. 4340 will be MUCH tougher at lower temperatures. 2% Ni shifts the ductile to brittle transition temperature appreciably-- for low carbon steels it would be a delta of ~ 100 degrees F, for medium carbon steels it is less.

Having said all of this, these alloys can be used for many of the same applications. If the application does not require the higher level of fracture toughness (especially at low temperatures) that 4340 offers, then 4140 can be used as a direct replacement, with the caveat that distortion during heat treatment will be higher and thicker sections will not quench to the same hardness. I would caution you against ever saying that an alloy is suitable or unsuitable for a generic application without fully understanding the operating environment (forces, temperature, corrosion, etc.). You may want to provide some additional details about the types of components you manufacture, their operating environments, etc. so that we can better answer your question.

But then i guess if they are doing the tempering it's what they say goes. i'm not a metallurgist. tougher the better imo for a high toleranced gear, maybe not so important if it was a push fit or alike (driveshaft etc)

keep us informed with more details, i'm keen but would like more info!

Edited by GT-RZ

Sorry for not replying earlier guys, had shoulder surgery on wednesday.

Generally things must be surface ground after nitriding due to the surface expanding unevenly. That is the gas can be absorbed at different rates in the material. However given that these are gears and not a bearing surface (like a crank) it should not matter as much.

Cryogenic treatment is excellent in making material stronger. So you have a good mix. Nitriding does nothing for strength but makes the surface very tough and cryogenics does nothing for toughness but adds strength (re-aligns the grains correctly i believe)

potentially Allows obviously a more plyable material to be used which IMO is a good thing when it comes to gears.

GTR standard pumps would be the go imo! Looking forward to these, hopefully a cheaper cure to this problem.

PS: How many splines are there going to be (sorry if this was mentioned earlier also) As obviously the more splines (think 10 splines per 25mm) the larger the surface area but with that comes smaller splines which requires smaller tolerances which may not be suited for the heat expansion that these gears will come under during the operation of an engine. Looking at the Supra design posted earlier in this thread would be a good way to go, not very many splines but it's clearly a tried and proven logic.

PS: If possible 4340 is the superior material compared to 4140 but obviously it does come down to the manufacturing processes s available.

Expansion from nitriding will be based on how long the material is left in the 'oven'. Seeing as we are only after a 4-6thou penetration depth, expansion will be minimal and this tolerance will be built into the original machining. Also the isotropic finish we are going to use will give us back some of that extra clearance, as this finish microscopically removes the 'peaks and valleys' on the material.

We are going to use 24 splines. The more splines used the greater the machining cost as cost is based on per mm of cutting. 24 will be ample for the size of these gears.

As greg posted below, 4140 is the material of choice as we feel its properties are optimimal for the application.

4140 is a good material for the gears. I spoke to the heat treaters who recommended it over 4340 because although the 4140 doesn't end up as hard, it will not be as brittle. Hardness isn't as critical as toughness for the gears as they are very well lubricated and wear isn't a big issue. Cost wise there's very little difference. If you weren't going to harden the gears you'd use en26 or similar.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Next on the to-do list was an oil and filter change. Nothing exciting to add here except the oil filter is in a really stupid place (facing the engine mount/subframe/steering rack). GReddy do a relocation kit which puts it towards the gearbox, I would have preferred towards the front but there's obviously a lot more stuff there. Something I'll have to look at for the next service perhaps. First time using Valvoline oil, although I can't see it being any different to most other brands Nice... The oil filter location... At least the subframe wont rust any time soon I picked up a genuine fuel filter, this is part of the fuel pump assembly inside the fuel tank. Access can be found underneath the rear seat, you'll see this triangular cover Remove the 3x plastic 10mm nuts and lift the cover up, pushing the rubber grommet through The yellow fuel line clips push out in opposite directions, remove these completely. The two moulded fuel lines can now pull upwards to disconnect, along with the wire electrical plug. There's 8x 8mm bolts that secure the black retaining ring. The fuel pump assembly is now ready to lift out. Be mindful of the fuel hose on the side, the hose clamp on mine was catching the hose preventing it from lifting up The fuel pump/filter has an upper and lower section held on by 4 pressure clips. These did take a little bit of force, it sounded like the plastic tabs were going to break but they didn't (don't worry!) The lower section helps mount the fuel pump, there's a circular rubber gasket/grommet/seal thing on the bottom where the sock is. Undo the hose clip on the short fuel hose on the side to disconnect it from the 3 way distribution pipe to be able to lift the upper half away. Don't forget to unplug the fuel pump too! There's a few rubber O rings that will need transferring to the new filter housing, I show these in the video at the bottom of this write up. Reassembly is the reverse Here's a photo of the new filter installed, you'll be able to see where the tabs are more clearing against the yellow OEM plastic Once the assembly is re-installed, I turned the engine over a few times to help build up fuel pressure. I did panic when the car stopped turning over but I could hear the fuel pump making a noise. It eventually started and has been fine since. Found my 'lucky' coin underneath the rear seat too The Youtube video can be seen here: https://www.youtube.com/watch?v=uLJ65pmQt44&t=6s
    • It was picked up on the MOT/Inspection that the offside front wheel bearing had excessive play along with the ball joint. It made sense to do both sides so I sourced a pair of spare IS200 hubs to do the swap. Unfortunately I don't have any photos of the strip down but here's a quick run down. On the back of the hub is a large circular dust cover, using a flat head screw driver and a mallet I prised it off. Underneath will reveal a 32mm hub nut (impact gun recommended). With the hub nut removed the ABS ring can be removed (I ended up using a magnetic pick up tool to help). Next up is to remove the stub axle, this was a little trickier due to limited tools. I tried a 3 leg puller but the gap between the hub and stub axle wasn't enough for the legs to get in and under. Next option was a lump hammer and someone pulling the stub axle at the same time. After a few heavy hits it released. The lower bearing race had seized itself onto the stub axle, which was fine because I was replacing them anyway. With the upper bearing race removed and the grease cleaned off they looked like this The left one looked pristine inside but gave us the most trouble. The right one had some surface rust but came apart in a single hit, figure that out?! I got a local garage to press the new wheel bearings in, reassemble was the opposite and didn't take long at all. Removing the hub itself was simple. Starting with removing the brake caliper, 2x 14mm bolts for the caliper slider and 2x 19mm? for the carrier > hub bolts. I used a cable tie to secure the caliper to the upper arm so it was out of the way, there's a 10mm bolt securing the ABS sensor on. With the brake disc removed from the hub next are the three castle nuts for the upper and lower ball joints and track rod end. Two of these had their own R clip and one split pin. A few hits with the hammer and they're released (I left the castle nuts on by a couple of turns), the track rod ends gave me the most grief and I may have nipped the boots (oops). Fitting is the reversal and is very quick and easy to do. The lower ball joints are held onto the hub by 2x 17mm bolts. The castle nut did increase in socket size to 22mm from memory (this may vary from supplier) The two front tyres weren't in great condition, so I had those replaced with some budget tyres for the time being. I'll be replacing the wheels and tyres in the future, this was to get me on the road without the worry of the police hassling me.
    • Yep, the closest base tune available was for the GTT, I went with that and made all the logical changes I could find to convert it to Naturally Aspirated. It will rev fine in Neutral to redline but it will be cutting nearly 50% fuel the whole way.  If I let it tune the fuel map to start with that much less fuel it wont run right and has a hard time applying corrections.  These 50% cuts are with a fuel map already about half of what the GTT tune had.  I was having a whole lot of bogging when applying any throttle but seem to have fixed that for no load situations with very aggressive transient throttle settings. I made the corrections to my injectors with data I found for them online, FBCJC100 flowing 306cc.  I'll have to look to see if I can find the Cam section. I have the Bosch 4.9 from Haltech. My manifold pressure when watching it live is always in -5.9 psi/inHg
    • Hi My Tokico BM50 Brake master cylinder has a leak from the hole between the two outlets (M10x1) for brake pipes, I have attached a photo. Can anyone tell me what that hole is and what has failed to allow brake fluid to escape from it, I have looked on line and asked questions on UK forums but can not find the answer, if anyone can enlighten me I would be most grateful.
    • It will be a software setting. I don't believe many on here ever used AEM. And they're now a discontinued product,that's really hard to find any easy answers on. If it were Link or Haltech, someone would be able to just send you a ECU file though.
×
×
  • Create New...