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I was giving you a windup Sean.
Of course its best to have stronger parts if you can afford to.
Agreed, most people will break a box before they run a 10, I was mearly saying, if driven smooth mid to high 10's can actually be quite reliable on a stock box.

Yanks are savage on gear so sell em heaps of the good stuff Sean :thumbsup:
 

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Yanks are savage on gear so sell em heaps of the good stuff Sean :thumbsup:
So then how about the Poms ? Since we are both a couple of sheep shaggers anyway right ?

You can go 10's, but you can break it also. I like to prepare people that they will break it. That way they think when they pull 3rd gear.

How many 4th gear synchros do people f-up ? Tons of them, they think they are Mario Andretti, and have to try and drive that straight back 3-4 shift as fast as they can..
 

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rob, do you run the stock 4.3 final drive in the gts-4 still ? that makes things last longer as it puts less stress on the gearbox
 

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1 week ago a friend of mine destroyed his box shifting into third.
bnr32
nismo twin
stock box

absolutely destroyed the box with 330awhp(mustang)
 

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Bringing this back up.

If its usualy 3rd that is stripped, OS sell a drag 1,2,3 gear set. I no alot of people who have or do run this set.
How much better is the OS gear set and does it solve the failure problem with out having to go for a super expensive dog/seq box?

Somethink else Im looking at is to be able to make a 200mph pass in my R32 when I manage to get the engine sorted. Is it possible to make it to 200mph on standard gearing without taking the rev limiter over 8500rpm?

Im thinking of going with the OS drag 1,2,3 gear set and using R34 diffs to balance the acc with top end. Would this be an OK set up?

Thanks Baz
 

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assuming rear end is 4.111
5th is .752

you would need a tire with a diameter of at least 24.44 inches to reach 200 mph at 8500 rpm
 

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The OS Gearset is stronger, but does not address all the issues of 3rd gear. I was fine with it in a car at 600 whp. 600 whp for quiet a few dragstrip passes and road racing. Then we had a customer that has a 2.6 with a GT42R on it. He had an OS box and broke third. He put this other OS gearset in his car, and broke 3rd again in about a month.

All depends on how you drive. If you drive it like you stole it, you are going to break it. First gear is not usually an issue. 2nd gear really doesn't break much. Third gear goes a lot. Don't pound third. Don't harshly engage the clutch in third. Its at the center of the stack, and the shafts bow a little, and the teeth move further outwards and they snap off.
 

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Right Im getting it now, basically if you force any of the boxes they will break.

Now I think another option was the input shaft. Dont no all details about this but if I opt'd for this upgrade does this up the strengh?

Ive been told the R32 standard will max out around 185mph.

Is it correct that the R34 6 speed box has the same ratio in 6 as the R32 does in 5th?
Differnce with the diffs is that the R34 is longer and there for gives you the high top end speed!

If I go for the R34 diffs with standard ratio R32 gear box then will it be possible for the 200mph?
Where the OS drag 1,2,3 comes into play would be the acceleration, I would lose out otherwise because of the longer ratio R34 diffs.

Will this be a good combo?

For info I will be building a RB30/26 with upto 600bhp at the wheels max. Main use will be track but drag and sprit will come into it quite a bit.

What are the prices of the seq boxes at the mo?

I no Im looking around £2000 to go for the set up Im talking about.
 

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look up at my calculations
that is using standard r32/33 gtr ratios
if you look on the site hugh posted you can find the calculator to figure it out yourself too.
 

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OK, I have had a play with the calculator....

Those are the top speeds possible and it says I will be looking at 240mph using a r32 box with r34 diff and taking it to 8500rpm.

Now can anyone tell me what or how to correct the speed when drag is involved etc etc....
 

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Right Im getting it now, basically if you force any of the boxes they will break.
If you change gear by pre-loading the gearlever, you will not in my experience break an OS Giken sequential.


If I go for the R34 diffs with standard ratio R32 gear box then will it be possible for the 200mph?
I can do 200 MPH from a standing start, as done at TOTB, in a mile on my car with R33 / R32 diffs, so there is no reason to change to R34 diffs if 200 MPH is your goal

Cheers

Hugh
 

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I guess what I will do then is find out how far I will go with the standard R32/33 set up.
I no I wont have the cash this year to go for somethink like a sequential box.

Hugh, what box were you using for TOTB?

The calculator says its poss with the standard set up, 207mph at 8500rpm and 219mph at 9000rpm.
 

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I guess what I will do then is find out how far I will go with the standard R32/33 set up.
I no I wont have the cash this year to go for somethink like a sequential box.

Hugh, what box were you using for TOTB?

The calculator says its poss with the standard set up, 207mph at 8500rpm and 219mph at 9000rpm.
I have used an OS Giken sequential for the last 4 years which includes all runs at TOTB.

I came 10th overall in TOTB6 last year so you can see the car featured in the TOTB DVD if you have a copy.

I use 9000 RPM on my engine, so a true 200MPH is well within reach.

Remember to set your tyre and wheel size when using the spreadsheets.

You will also have to check you are using the correct ratios although I just remembered I put R33 and R34 standard gearbox spreadsheets on my site which should make it easier to look at.

Cheers

Hugh
 

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Ive been a marshall helping out Chris and the others for 3 years now, I do have the dvd and will watch it when I get 30 mins spare.
Hopefully Ill find out this year what the car is capable of, just hope I get the engine sorted and built without fuss unlike my cosmetic change for it!

Yes, I did put in my tyre size (265/35/18), standard R32/33 box (0.752 in 5th) and diff (4.111) and hopefully they are correct. Thats what Icydude quoted.

Would be good to no about drag effecting those speeds!
 

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To assist with road ECU mapping, I did a spreadsheet a few years ago to look at drag and the forces required to accelerate the car, that took the logged output from my ECU to calculate the BHP between logged events in RPM or Speed.

The biggest problem is determining the coefficient of drag.

I think it may be possible to establish the drag coefficient by doing coast down tests from a known speed, but there are still issues with transmission losses to determine engine BHP rather than car BHP.

Cheers

Hugh
 

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R32 Nissan Skyline GT-R - Specs / Specifications

This gives you the drag coefficient, 0.40cd (R32 GTR)

Surely by using the standard cd you will be able to work it out.

I do have another problem! Speaking to my mate about the RB30/26, it is advisable not to rev past 8000rpm. So that takes out the 8500rpm or there abouts I was hoping for.

Guess it will be just a case of getting hold of some R34 diffs and swaping them over for a day of high speed runs sometime.
I want to see 200mph, an Im sure I will get there LOL
 
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