Should i have been faster with Mfactory straight cut?


MFactory said:
Have you ever designed a custom set of ratios for a race car based on the circuits that it will be racing on? If not, please don't tell me that there aren't any other details missing. There are a lot of variables involved.
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I can certainly see the merits of specifying gear ratios for a particular circuit, but that is in the realms of BTCC level motorsport, above and beyond the interests and capabilities of anyone racing an old Honda in the UK.

At best I can perhaps see someone sorting the gearing for their local circuit, but even then I'd be surprised to see that much effort going into ratio selection.

I maintain that unless you are doing the above, an evenly spaced set of ratios that do not significantly under or over gear the car are best for general use.
 
a lot of discussions here. i think this is very good, because argumentation tells us most about how everything work.

maybe there are some calculators, which can do somekind of calculations? i found sometime ago a cac for 1/4 mile strip and when I entered shorter gear ratios, the calculator showed me, that I will not run the track faster. It even showed me to gear from 1st gear to 3rd if i remember correctly, or from 2nd to 4th. So this means that there is no gain or even loss than going in the straight line.

Yes, I understand that if you build the box for certain track, you can win by having a right gear in every or most corners, but... but who of us have such budgets and can have 4 gearboxes for each tracks? so tha conclusion is that there is no point of building a short ratio box for overall track/drag use?

Now I am quite happy with my oem box, but 4th and 5th gears are so slow and I can feel this with my ass :) So as I understand stock vti 4th and 5th will solve this?

Is it worth putting m factory 4th and 5th, which will be even shorter than oem vti ones? As I am not really going to run the car at 150mph, maybe 120 maximum. I need a maximum efficient transmission for overall track/drag strip use. My tires are 205/50/15.

Thank you.
 
For a drag car, you should always gear the transmission to cross the line at the end of 4th gear.
 
MFactory said:
Again, you can't make assumptions without knowing what his application is.

All of your "assumptions" are based upon "distance" rather than "speed". Yes, on a freeway, "distance" is what matters and yes, a longer geared transmission would have an advantage ultimately.

But these gears were designed for racing where distance is limited, hence the requirement to achieve maximum speed within the set distances.

A shorter geared transmission will reach any desired mph faster than the oem transmission and that is what matters on a closed circuit, especially one with a lot of turns.

This is why a race car with a pre-determined 120mph top speed using a transmission geared for 120mph is more efficient on a race track than a transmission geared for 150mph.

It all comes down to application :)
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Ofcourse a 120mph car of the same class will be more efficient than a 150mph car.

The ratios on my car are as follows from the gear calculator.

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15" wheels - 195 / 55 / R15

Final drive 4.4

Rev limiter @ 8500 ?? - shifting @ 8300 ??

1st 71km ratio 3.070
2nd 103km ratio 2.105(oem 2nd gear) 5857rpm
3rd 127km ratio 1.704 6883rpm
4th 160km ratio 1.355 6744rpm
5th 194km ratio 1.118 7010rpm

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I can thell that , as you will be amazed by how fast and efficiently the car can reach up the 194km/h top speed compared to the stock ek9 transmission.
On the 1/4mile from jump start the car reaches the finish line just before the rev limiter on 4th gear when engine is clean. So i guess this is good for a little 1.6L.
The torque gain from shorter ratios also compensates better fuel consumption while in city driving.
(Forget about freeway driving).

A slight issue i found is if you change gears at very low rpm like 2-2,5k on the straight cut there is a crunching noise. I dont know if its from the fact of the very light flywheel 4.0kg i use.
 
so it seems that oem s80 4,785 fd box is the best for drag, as now I am finishing near redline with current setup :S so aybe it is the best for overall use also? just 5th gear maybe shorter?
 
Stakis said:
so it seems that oem s80 4,785 fd box is the best for drag, as now I am finishing near redline with current setup :S so aybe it is the best for overall use also? just 5th gear maybe shorter?
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B18C is another story :)
 
Kozy said:
A 2.0 B series is another again!
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Short Block (b16b-b18c block) easily ...

Wheres the b20 think needs sleeves to work properly. Seen so many crack sleeves and leak from their Crv block :)
 
ye, i heard also about these problems, but never had them with my builds. i am running the engine for 2 years now. in all ways of motorsport events, drag racing, some everyday use etc. offcourse, mine makes only 240bhp, but it runs on completely stock bottom end.

so any advices on my gearbox build? i really was hoping to get some noticable gains with the geabrox built, but now I am a bit confused about this.

thanks
 
Stakis said:
ye, i heard also about these problems, but never had them with my builds. i am running the engine for 2 years now. in all ways of motorsport events, drag racing, some everyday use etc. offcourse, mine makes only 240bhp, but it runs on completely stock bottom end.

so any advices on my gearbox build? i really was hoping to get some noticable gains with the geabrox built, but now I am a bit confused about this.

thanks
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Contact synchrotech - mfactory for the carbon lined synchros , gearbox bearings , seals and rings. Then call your local Honda dealer for the complete sleeve (in & out for 1-2 , 3-4 , 5-R) and new LSD Bearings ? :)
 
i wanted shorter gears m8 :) and gain some advantage in the track with them... :)
 
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