Time attack gearbox options

[VS15]

Hi all ,

Would like to get your feedback to build a s15 gearbox that can withstand 500hp and 550 Nm (tq) . I recently blew up my stock 6 speed and would not want to change back to that so my option is either go with the 5speed s14 or rb25 route .

Am searching for the most cost effective manner for time attack on a fairly highspeed track in sepang malaysia.

Thanks

 

[S15_SAM]

Would defo be RB box or Z33 box which are primarily the same. Best cost effective way with that power. S14 box would die in 2 seconds!

 

[VS15]

Thanks for the information... is S14 box really that weak?

I can only see powertune selling adapters for SR mated to RB gearbox..... what about the z33 you speak about?

and are the gearbox ratio for RB box good for time attack high speed track application?

 

[S15_SAM]

Sorry I'm getting confused. The z33 is the 6 speed 350z box, I ment the 300zx 5 speed box is the same as an rb25 speed.

The z33 6 speed conversion has been done before but tbh I'm not sure how strong it is. The RB box is proven to be reliable at 500bhp where as I'm not sure the Z33 box has. Here's a link to what you need and they say the Z33 box is tough but pricey! http://zilvia.net/f/drivetrain/370705-z33-sr20-adapters-back-limited-quantities.html

As for high speed events I couldn't tell you! It will have good ratios for top speed you just may need to swap out your diff for something with alittle higher final drive ratio. How fast are you expecting to be going?

 

[ichigo-300]

There are some issues also with early versions of the Z33 box, the later versions are ok.

Apparently the ratios using the Z33 6sp box in the S15 isn't ideal, but.....

Mazworx have made a prototype adaptor kit which is working (they posted a You Tube vid of there S15 running this Z33 kit just before Christmas).

I'm looking at this kit as well, as 500bhp should be fine in it.

The traditional route as S15_SAM has said is the RB25/Z32 5sp route, if the standard box isn't enough PPG do a 1000bhp gear set for it, so no worries there.

or VQ30 transmission with an adapter plate from Mazworx

If you must go 6sp and if you looking at Time Attack you might also want to go sequential box, then the following are the options I know about:-

- Quaife 6sp sequential
- Holinger sequential (as used by the Scorch Racing 700bhp SR22VET Time Attack car)
- HKS sequential (27003-AN011)

All mega money, the Quaife and the HKS are the cheapest at around £6k, the Holinger runs at more than double that. Expensive game Time Attack.

Your best bet for reliable gearbox running is the RB25/Z32 conversion to 5sp and if this isn't enough then add the PPG dog set upgrade, it's helical as well so not so noisy, if you what to go straight cut is another $2k.
(http://www.mazworx.com/product/driv...3r34z32/ppg-14th-helical-dog-set-r32r33r34z32).

I'm hoping to run 650hp in my build and i'm currently leaning towards the Z33 conversion with modified internals, or the Quaife sequential. Some Time Attack rules forbid sequential transmission unless they were OEM, so depending on which division i'm entering will dictate what transmission option I have.

Good luck...

 

[VS15]

thanks for the feedback . will look into it =)

 

[lvaleiron]

The Z33 appears to be a good option to keep a 6 speed box and the good reliability of the z32 one, of course, you'll need to get the latest models of them (07 ~ ) and several stuff like adapter plate, custom drive shaft, modify the bell housing, make a new trans. mount, modify shifter bracket, modify slave thingy and i think that's about it. Also Ichigo, why you say the ratio won't be ideal??? They are very similar to those found on the S15 6 speed, even the final drive is a bit close:

Transmission	SR20DET (S15)	VQ35DE (350Z)
6-speed manual
1st gear ratio	3.626	3.794
2nd gear ratio	2.200	2.324
3rd gear ratio	1.541	1.624
4th gear ratio	1.213	1.271
5th gear ratio	1.000	1.000
6th gear ratio	0.767	0.794
reverse ratio	3.437	3.446
final drive (diff)	3.692	3.538

After much thought, this is the route I'm planning to go, so hopefully by April i can have this tranny mounted on the s15 , need to sort a latest model (before HR) in good condition and price tho. I have read a lot on this, so if you need any additional information please let me know. Cheers bud!

 

[VS15]

For the z33 6 speed conversion , its not as straight forward as the rb25 conversion is it ?

Retaining a 6 speed for time attack will be nice but am looking for an easy conversion

 

[gunner93]

Hi JK, my heart goes out for you with the 6 speeder under a high horse power driver.

One S15 owner in our group Alvin has fixed a dog-box in his S15. He has tracked his car in Sepang before. If you are keen to get his feedback or drive his car <slurp slurp>, let me know when you are back so as we can hook up with him.

 

[VS15]

Lol its ok bro , part of motorsport .

Am just going through the options with pitworks so that it can last longer for most events this year lol

Need to balance cost n parts availability , dogbox is definitely nice but will burm a hole in my pocket hahhaah

 

[VS15]

Lol its ok bro , part of motorsport .

Am just going through the options with pitworks so that it can last longer for most events this year lol

Need to balance cost n parts availability , dogbox is definitely nice but will burm a hole in my pocket hahhaah

I will be back this friday heheheh

 

[gunner93]

In our market, RB25 RWD 5-speed is more readily available than the Z33 ones. I'm sure Mun Lee will have a few sets and Lau can do the swap.

If you like, come and yam cha with us this friday nite. Aman Suria Kayu Restaurant. I havent told you in heat 1, this green 280Z lost control in turn 14 and almost cut in front of my car?

 

[VS15]

I will be there at kayu , yea asking lau if he can do it since he never did it before .

Thought I can have the car back by cny to cruise around lol but guess not .

 

[lvaleiron]

For the z33 6 speed conversion , its not as straight forward as the rb25 conversion is it ?

Retaining a 6 speed for time attack will be nice but am looking for an easy conversion

I don't know everything that is needed for the RB25, but should be very similar "conversions". The only down point i can see to the z33 6 speed is the availability of it in some places, that's all, oh and the bell housing that needs to be modified, which you need to locate a good shop that can do it. But from what i've heard and read, this box can easily handle 500hp or so, of course, torque is what kill trannys but gives you an idea of what it can hold.

 

[Fruitbooter]

Dont bother with RB25 this would get destroyed with that much power, they are still only a 250-300bhp rated box!

Your best bet is to go Z32/33, theres a few guys with big power on nissansilvia.com running them I think.

 

[VS15]

z33/z32 gearbox are not as straight forward are they? cause not much info i can find online

 

[lvaleiron]

z33/z32 gearbox are not as straight forward are they? cause not much info i can find online

To get any of these boxes into your car you"ll need:
0 - The transmission obviously...
1 - Adapter Plate: to mount the transmission to the engine, this can be bought from madzwork and some other companies that are in the business, or make it your self.
2 - Modified Transmission Mount: This goes without saying...need to make a new custom or modify your transmission mount.
3 - Custom drive shaft: The one you have won't work, maybe you can do only one half as the standard is two driveshaft jointed in the middle or make a one piece complete one.
4 - Custom shifter bracket: As stock the shifter bracket won't align properly to the shifter hole in your car.
5 - Connect and modify all connections as needed: the two switches (reverse and neutral) have different connectors i think and maybe modify the clutch slave cylinder lines (z33 definitely need to modify the clutch slave line).
6 - (Z33 only) Need to grind down the bell housing a bit as the adapter plate adds some space and the transmission shaft won't engage properly into the engine.

All the other stuff should work OK, even the engine starter fits great as i have heard, but someone here can confirm that.

 

[drifter]

Dont bother with RB25 this would get destroyed with that much power, they are still only a 250-300bhp rated box!

Your best bet is to go Z32/33, theres a few guys with big power on nissansilvia.com running them I think.

VG and RB boxes use pretty much the same gear set, synchros are a bit different though

I've just fitted my VG gearbox into the S15, easy enough. Need to bash the trans tunnel to make room, plus if the engine is in the car it helps to drop the subframe abit. especially if you use a multiplate clutch

Mazworx still do the VG kit, and have nearly finished the VQ kit as well

 

[Fruitbooter]

Dont suppose you fancy doing a guide how to fit a vg box?

I.E What do you need? Adaptor for bell housing? Custom Prop? Mounts? Modify transmition tunnel? Shifter location?

I just know later down the line I will need a new box so would like to learn as much as I can now and decide what box to go for case a cheap one comes up

Might just save and whack a 2jz engine complete with box in there...that would be fun and also strong!

 

[ichigo-300]

+1 for the VG guide...

The PPG gear set is available for both the Z32 and RB32 boxes (via Mazworx and others) which makes the box good for up to 1000hp, so if you need to upgrade the box as you power increases this is the option.

[h=1]PPG 1-4th Helical Dog Set R32/R33/R34/Z32
[/h]
$5,550.00


[h=1]PPG 1-5th Straight Cut Dog Set R32/R33/R34/Z32
[/h] $7,500.00


Mazworx info

Able to withstand over 1000 engine horsepower, this set has endured punishing abuse in all corners of the globe and has an unrivalled reputation as a near bulletproof drivetrain solution for those not wanting to fit a costly and sometimes less reliable sequential gearbox to their GTR, GTST or Z32 300ZX.

A direct fitment product that comes complete with 1-2 and 3-4 billet selector forks.

PPG manufactures a solid billet mainshaft product for use in GTR applications that is recommended for vehicles exceeding 900hp.