what to do with this

Matt - USA data not readily applied to UK cars. We never had a 4 speed or a 3.364 ratio.
The 280ZX data has even less relevance to what might easily be found in a UK car...we had 3.7 and 3.9 R200s and 3.545 R180 in the autos.
 
I realize that Mike.
The point I'm trying to make is that all 3.5s in this country will be R180's NOT R200's.
 
Wyn said:
Sure its a 3.54

What's the trick for working it out without pulling it apart
Spinning the prop and counting the shaft turns or something along them lines ?
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I doubt its a 3.54 wyn
chalk a line on the tyre at 6 oclock get daughter to look at mark until wheel turns 1 whole revolution as your turning the prop firstly marking a point and count revolutions untill daughter shouts OK then you have it ie prop turns 3.7 times for 1 turn of the wheel
 
Not too much work to open the cover and check the marking.

Is yours still a stock final drive as far as you know Wyn? If so its likely a 3.54, just checked my old one and that's what it was.
 
I'm running a 3.7 and my shift light(set for 7100rpm) comes on just after I cross the line in my 1:1 gear. My next mod should see the terminals move to the higher 130's and reving around 7500rpm in the same gear. IMO others should be doing the maths/using the calculators to arrive at the same in your 1:1 gear. I currently run a 24" diameter tyre but have the option to go back to a 50 profile to avoid changing into 5th.

Look at the Escort boys and how they pick the right final ration to make full use of all the gears and cross the line at the very top of 5th gear.
 
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I guess it depends how you look at it Terry. If your gear changes are quick then with the 6 speed box you will be quicker through the gears than a 5 speed. With your linea power graph you will want to keep high in the rev range. With the 5 speed, or using less gears, with each change you will drop into a lower part of the power band. At the end of the day I think you need to be crossing the line at the top end of a gear in order to get the most of your ratios.
 
Maybe you should switch to a 5 speed box, 17kg lighter, better and more accurate **** action, its what all the m3 (e36/46) race cars get fitted with. They're stronger and cheap as chips also.
 
racer said:
I realize that Mike.
The point I'm trying to make is that all 3.5s in this country will be R180's NOT R200's.
Click to expand...

Not sure about that Matt I have broken a couple of 2+2s and seen 3.5s in the past and have just secured the purchase of a nice low mileage R200 one from a 2+2 uk car.

Now the future plan is up the rev limiter to 8200 rpm get a few more runs in on the 3.7 which should keep me (depending on power) in 4th gear across the line up to 130 mph

Then swop out the 3.7 and in with the 3.9 which maxes out at 123 mph in 4th but can carry on to 151 mph in 5th note the results

Then in with the 3.54 and see what happens, capable of maxing out to 136 mph in 4th 167mph 5th 196 mph in 6th :eek: all this fairly cheap on the pocket but a fair bit of graft involved, what I am going to do in the next couple of weeks is get another two power runs done at different RRs

Now the expensive bit

Drive shafts, yes I know I can research it but the brain can only take so much in now days, so what do I need and where from ? running R200 and 260z stub axles

Or what have you got ££££ waiting
 
Saw this featured in a Jap against a 260z (2+2) with a skyline motor.... looked an awesome feature!!!
 
Sounds like a lot of work swapping all those final drives.


I haven't used my CV driveshaft setup with the RB yet, but its definitely the strongest option out there. I'm using Z31T CV's with custom shorter and stronger shafts and Chequered Flag Racing Billet companion flange adaptors, also running billet stub axles. Not the cheapest setup but at least you don't have to worry about breaking it. This is also the setup that Wyn is using I believe.
 
Ian said:
I'm using Z31T CV's with custom shorter and stronger shafts and Chequered Flag Racing Billet companion flange adaptors, also running billet stub axles. Not the cheapest setup but at least you don't have to worry about breaking it. This is also the setup that Wyn is using I believe.
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Yup :thumbs:

Touch wood nothings broken yet :)
 
I'm running exactly the same as Ian and Wyn.

I think this setup will take the power I'm running OK. It's just the way I treat it through the gears that could be a problem. You commented when you joined me down the strip that I wasn't mechanically sympathetic. From the sound of it, your dual mass flywheel and rubber driveshaft donuts mean there is very little shock load on the drivetrain compared to mine so you may get away with what you've got already.
 
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Sadly, on the drag strip (or any other motorsport event) vehicle sympathy and performance are diametrically opposed, hence the term "drive it like you stole it"
And from personal experience of hundreds of ¼ mile runs, there is only one technique and it most certainly isn’t for the faint hearted.

We've also often used the term "wallet brake" ................ it’s the biggest performance inhibitor around, and is fitted to most Z’s, consigning them to standing in a field having their chrome polished with the owners swapping stories of BHP figures that get bigger every time, those that have removed the “wallet brake” are at the top of the hall of fame :bow:
 
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