Merlin's 4G Time Attack Lude

[Merlin]

Thanks bud, I cant wait to get oily and fit these! Just what oil?

[Dino]

Gear box synchro fail was due to using a mix of used parts from 2nd hand boxes.

Still use and always use Amsoil MTF.

[Merlin]

Yeah I use Amsoil MTF at the moment, and also in my 5th gen, it's good stuff. But I dont think it will cut it with the Kaaz LSD. You are right I need to get Rich to explain properly.

[Donald]

Thanks bud, I cant wait to get oily and fit these! Just what oil?

Baby oil

Or am I answering the wrong question?

[vanzep]

ouch my head is spinning
what a dilema on what gearbox oil to use
if you cant get a definative answer then id be tempted to use Honda MTF after the lsd is broken and see how it goes from there.....but you really need an expert to guide you on this one given the amount of cash that you spent on the gearbox build.

[Merlin]

Yeah Donald that is the correct answer to a different question

Nick it's a difficult one to figure out.

[vanzep]

I didnt help any did I

[Merlin]

I have been calculating out the ETE (Engine Torque Equivalent), a theoretical value that estimates the torque needed by an identical car with a stock final drive to accelerate at the same speed as the MFactory FD, to see if ETE increases inline with increases in base torque and also to see the ETE % my car produces over stock.

1st Gear Ratio - 3.230
Final Drive Ratio - 4.4

3.230 x 4.4 = 14.212 absolute ratio. What this means is that, for every turn of your wheel, your crank will have turned 14.212 times. From this, we can calculate the total torque produced to the ground:

Absolute Ratio x Engine Torque = Torque to the Ground. This is what you actually make to the ground, not what your dyno graph tells you.

What I worked out using the above formula.






Basically because the caculation is based on static ratios ETE increases at a set percentage. I will see an 14.2% increase in effective torque over the M2F5 FD and an 8.8% increase when compared to the FD found in most other Prelude gearboxes.

What this really means is that at the end of all of my upgrading, and using the M2F5 gears, I will see an estimated 43.2% increase in effective torque compared to just a 40% increase in BHP, over what I have at the moment with my H22a2 and stock FD. Without the MFactory final drive torque would have only increased by 25.3% (188 over 150 lb/ft)

The 2nd outcome is that the calculation shows that another Prelude with the more common stock 4.266 final drive would need 204.5lb/ft to acclerate at the same rate.

When I get bored I might work out what the ETE would be if I put the MFactory in my spare M2P4 low ratio gearbox.

[Edson]

Nice results Merlin and also nice calculations. Explains a lot.

But errr, doesn't that M2F5 just had a FD ratio of 4.266 ?
Last time I checked it does.

[Merlin]

Thanks The M2F5 & M2V5 have a final drive ratio of 4.062 and not 4.266 like all other VTEC gearboxes:

http://www.ludegeneration.co.uk/gearratio.php
http://www.ludegeneration.co.uk/honda-p ... t2130.html
http://preludeuk.forumup.com/about4935-0.html