Question S80 drag gearbox


MichaelEK9DK

MichaelEK9DK

Active Member
Joined
Jun 23, 2014
Messages
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Hi Honda'guys! :)

I will build a S80 4.4 gearbox into a little more fun gearbox.

I want a better drag-gear than I have so far, it is very low geared for 3 +4.

I have 8600 rpm and running with 195/50-15 small deck
One day, the engine rebuilt, and more rpm, I'll remember :)

I've looked at Mfactorys gear converter.

And come up with this solution:
FD 4.923
lower 1 gear 3.07
Normal 2-3-4
And a further 5 gear 0.787
Here it is held up with a 4.78 (OEM) FD:
http://www.teammfactory.com/gearcal...rratiof=0&tranny=Calculate+Transmission+1+&+2

Someone who has a good advice or constructive criticism?

Regards Michael.
 
Last edited:
JohnTurbo said:
What ar you trying to achieve? What engine specs?
Click to expand...

As I write, I try and achieve a better drag gearbox, ie 1/4 mile, even with normal driving in town (do not use it on a daily basis)

The engine is std, but takes 8600 rpm and throw 227 hp and 204 nm.

My 1/4 time was 14.5 seconds, and this can be done better with a modified gearbox.

My old S4C jdm has been very low gear in 3-4 gear, which fits perfectly with the track :)
 
Surely you would want a close ratio 3/4/5 set, then match it to a final drive that suits your strip? MFactory still have some straight cut gears left, some good ratios, if you did not like the newer ratios. If you have an Ipad/Iphone get yourself the 'Fortin Racing' app, very good.
 
haitch said:
Surely you would want a close ratio 3/4/5 set, then match it to a final drive that suits your strip? MFactory still have some straight cut gears left, some good ratios, if you did not like the newer ratios. If you have an Ipad/Iphone get yourself the 'Fortin Racing' app, very good.
Click to expand...

It is a close ratio set I run with just pt.
I just read everywhere that the best is a higher final drive and it gives more torque?
This is the two setups against each other http://www.teammfactory.com/gearcal...107&gearratioe=0.787&gearratiof=0&trannytype=
There is not much difference, but as I said, people write it more torque?
 
Pt?

What are your actual 1-5 ratios now? I cant read those tiny boxes.
 
Indeed... a higher number ie 1.6:1 rather than 1.2:1 but this is known as lower gearing not higher. Higher will lose torque at the expense of top speed.
 
QUOTE=haitch;731498]Pt?

What are your actual 1-5 ratios now? I cant read those tiny boxes.[/QUOTE]

Pt, right now :)

Ratio in my S4C 4.4
1. 3.230
2. 2.105
3. 1.652 (std 1.458) close ratio
4. 1.306 (std 1.107) close ratio
5. 0.848
 
JohnTurbo said:
Indeed... a higher number ie 1.6:1 rather than 1.2:1 but this is known as lower gearing not higher. Higher will lose torque at the expense of top speed.
Click to expand...

Dont understand it John, is will be bad whit 4.923 fd? I know i will lose top speed, thats way i choese 5 0.787
 
What do you normally cross the line at on your strip?

If you are still in 4th, with the gears you have and 4.4fd, your top speed in that gear is 101mph, but if you use a 4.9fd, you max top speed in 4th will be 91mph but as you are using the oem 5th ratio the revs will drop 3016 as you change up, dropping you right out of the power band, its a big drop. Why not run a shorter 5th?
Sure you will lose top speed with a 4.9 (15mph) but you will never hit this anyway.

Having tried a short 3/4 combo with a longer 5th I know it can be horrible to drive as you charge up the gears the car just bogs down.

Left: oem & your 8600rpm. Right: your short 3/4, 8600.


So hopefully I have the details correct here :)

Left: your short 3/4, 8600/4.9fd. Right: your short 3/4, 8600.
 
Haitch, Thank you for your nice words.
I think we misunderstood each other?

If I change FD in my S4C seems to run too far down.

Therefore, I would buy a S80.
And put 4,923 FD in.
1 3.07 (OEM 3230)
2 2,105
3 1,458
4 1,107
5 0.787 (OEM 0.848) So I keep still a little top speed.

It is this mix that I will hear about help? :)

And total refurbish the gearbox with Carbon Syncro rings and new bearings
 


Left oem ratios with 4.78, 8600. Right: your latest setup.

Seems a bit more even maybe, but is a gear set more beneficial on this application? Its all about the rev drop as you change up, with a closer set you only drop 1-1.5k depending on ratios, straight into the power band for n/a, not that I have been on the quarter mile mind :naughty:

Any other quarter mile folk care to input?!
 
One of these days I also get tuned my engine, and would love to have the gearbox right there, so I also get more rpm, also should all fit perfectly? :)
 
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