Gear ratios.

[hattech-v]

change ur 1st gear to 2.222 then 2nd to 1.688, 3rd 1.568....

then boost at 2bar.... kekekeke

 

[evoX2]

evoX2,
nope..m only looking 2 chg d 3rd gear ratio..can it b done?changing just d 3rd n maintain d rest?anyway,y u say i need 2 chg 1st as well?n who has it?ur location so far....dun tell me sumwhr in ur hometown ar?hehehe

if u change 3rd gear alone then no need to change 1st gear, i thought u want to change 2nd gear as well. someone in seri kembangan would have it soon, i'll get it swap with his stuffs :P

hey hattech, 5.0FD can use on normal driving kah? then the petrol would be like crazy?

 

[shiroitenshi]

Akuma,
3rd gear no need the shaft. The gear + the gear on the layshaft (for those unfamiliar with the terms) the gear with synchro (that's one) and the gear that meshes with it that doesn't have the synchro (the other pair). I've heard people rojak, but for me the meshing of the gears might not be so nice anymore, and you won't get the exact 1.36 ratio you're looking for.

EvoX2,
5.0 FD can use for normal driving.. the 5th gear must be very low, maybe from the 4.785 FD gearbox, or aftermarket ones that are lower than the 0.787 that's in the R and the GSR gearbox you are using.

But in real life application, the 5.0 might just be nice for your GSR ratios, since they are rather big for the stock 4.4FD.

At 9k rpm, 1st gear gets you 60+kmh, 2nd gear gets you 106kmh, 3rd gets you 148kmh, 4th gets you 195kmh, and 5th is 256kmh

100kmh cruising at 5th is about 3.5K rpm.. which is very near stock Y21 g/box/type R. This is all based on using the tire size of 195/55/15. With 205/50/15, should be a little different, while 16" should deviate even more.

Now you know why mat salleh like the GSR gearbox and swap FDs for it.

actual application depends on how your torque is though.. if you have big low end torque and your torque curve takes a dive after 6K-7K rpm.. mampos le using gearsets that seem to like high RPM.

But evox2, the meter is not accurate.. true 9K you need to measure from the plug or coil.
The EG meters shows rev cut in at 8.4-8.5K, but in reality, it cuts at 7.8.. which is what I got when I plugged in the auxbox.

EK9 meter even better.. 10K is only 9K+ rpm (actual)! (O_o)

 

[evoX2]

thanks for the info shiro. but i am swapping all my gear ratio to 98 itr ratio, just havent decide on the final drive, should i go for 4.7 or higher? i'm using 215/16/40 tires.

 

[shiroitenshi]

if you go higher, you get more torque, but you need more RPM to get the speed.

I can plonk in 5.0 in my Y21 (assuming I can actually make the gear clear the housing, and I'd get more torque to the tires but it would seriously kill my top speed.) 2nd gear won't even touch 100kmh! LOL!

Biggest I've seen is 4.9.. never seen (or heard of) the KAAZ 5.0.. and if your car can really rev up to 9/9.5K, you could have retained your GSR ratios and used that, but unfortunately, you don't have a dyno, so you don't know your torque... If your torque peaks at 6-7K, I think your acceleration will suffer if you use ratios that are more for high RPM..

Remember that most hondas have peak at about 6-7K when stock, so revving up higher usually doesn't result in better acceleration.

As for the torque, in drag, only the first gear sees pre-5K torque, as the rest, you're already at more than 5K rpm (or 6K, if you're running different ratios than the standard one), so that 5-9.5Krpm torque range is what's going to make your car go.

Which is why a non rev limited B16A (temporary chipped ECU while waiting for Hon'tada')still makan asap at 9K
(or course, that was during a side by side with a friend's 500whp evo.. hahaha, unbelievable, but it was a fun fun impromptu thing while going for TT.) I think you might have seen it at links when it was tuned by the Japanese.

Only the first gear I could pull ahead slightly, but as soon as I past the 7K rev limit.. kena tinggal already. (only tested 1st and 2nd gear, but at 2nd, I was like 3 cars behind already.. ha ha)

Ok, so it wasn't a fair test.. LOL...

IMO,

If ITR stock ratios.. for those car that have peak torque at 6-7K, and then takes a nosedive (valve float/flow issues/whatever), Mampos!.

If I'm building a high rev engine, I'd target peak torque at 8-8.5K, rev limit it to 9.5K, and use the stock ITR gearbox..

I think for most people successful in drag, their peak torque is usually at 7K or more, or at least have no significant loss of torque past 7K. Mine.. about 7-7.5K, which is how I got the 160whp, but after that, nosedive! I only get 130whp or so at pre-8.5K...

Anyway, how are the valve springs holding up? It was a cheapo idea of mine for those sticking with minor mods. I think at 9K, you'd already be suffering from valve float issues.

But from your plans of doing it slow, I already said you should have gone with aftermarket ones.. that is only for budget modders sticking with B16A with mild mods. My friend and I sorta thought you wanted to go further, which is why my friend was quite set on convincing you to use aftermarket v/s.

But I'd beware of using 2nd hand aftermarket v/s though.. stress crack on one of the springs = no engine, and you know as well as I do that previous owners of aftermarket valvesprings don't drive 'casually'.. LOL.

 

[evoX2]

thanks for the advise, actually my car seldom move at all since i am not in, even if i drive i just keep the rev limit to my gauge 8.5k only. i know the vs & retainers wont hold up for higher rev. i'll change to after market one soon, but how to choose vs spring spec? need to check the highest lift of the vs? if i use only on ctr cam then overkill right? if the vs "too hard" also no good right?

since my engine mod to similar type R, guess the power band shouldn't be much diff, now i am getting all the R ratio, then i should just stick to the 4.7 fd?

 

[shiroitenshi]

Good brand Vs all the same, some have different spring rates. Some maybe design-wise different, but they do the same thing, return the valves to the valve seats.

The harder it is, the more wear it will cause, but it will be more reliable at high rpm.

As for powerband, you'd be surprised at how different it will be.

two similar spec B18C do not have the same powerband.. as dynoed before.
I can only guess that it's due to the cam settings (or the extractor/exhaust choice), as even the peaks are sometimes different, even though the rest of the parts are the same.

You're probably hitting 105-110kmh at 9K, not 9.5K (should be about there, I don't know your tire size so I can only estimate it.)

If using 4.785, you're going to hit only 100kmh at 9K with 2nd gear, shift, and you'll end up just a little before 6.5Krpm (the meter will probably show 6.5-7)

Since you don't have a dyno.. I suggest looking for a second hand RSM and a g-sensor. you can see how your power is like by taking a pull from 3rd from pre-3000rpm to rev-cut (or your own manual rev-cut, if you're not limited.)
Then you can see the point where acceleration is the greatest.

I already know mine... now using a non-rev cut ecu, and the car acceleration actually is slower past 8Kwhen I used the auxbox to test. (O_o)

 

[akuma]

1.36 1.36 1.36 1.36

 

[shiroitenshi]

1.36 1.36 1.36 1.36

If you swap to 1.36 and you have enough power to finish 400m at 3rd gear, okaylah.. if not.. better check where your 4th gear rpm will start when you finish your 3rd gear. if it's too far and you fall out of your torque powerband.. that might be a problem.

 

[akuma]

shiro,
shudn't b a problem...y i mati2 wanna swap 2 1.36 coz it'll b quite similiar 2 my old Y1's 3rd gear w d 4.2FD.....i was in my Y1 last time whn i took on a Supercharged SEG w 19kgm torque!!!by 2nd gear he was abt 2 cars' lenght in front of me..once i popped into 3rd...i reeled him back like his car is not moving.....so i blid a swap 2 d 1.36 will do me good....wat more w my new engine.....shud b healthier..heeheehehhe

 

[shiroitenshi]

Well... good luck.. but it would mean two things:

Either your car is very light, or your engine very torquey at mid to high revs.

 

[akuma]

shiro,
der's no either..if i say both oso YES?hehehehehehehe

 

[shiroitenshi]

Hahaha.. of course possible oso. :P

 

[eddie_vtec]

look for fei lo vtec lah ask his opinion

i agree...fei lo is king g.box ratio for vtec...ur gearbox ratio setting by fei lo or ur own setting?

 

[evoX2]

shiro,
der's no either..if i say both oso YES?hehehehehehehe

akuma's car is light weight, how about the driver? also lighten? haha...

 

[akuma]

evoX2,
naturally lighten.....just need 2 head 2 d "bank" n "deposit" sum poo thn ur ready 2 drive..hahahahahhaha

n yeap..heard of feilo's gbox nowadays oso....darn it..sum more got marking kenot open 1..hehehehehhe

 

[hattech-v]

anyone using it?

 

[evoX2]

u mean he seal up the gear box? cant open to check the ratio one?

 

[hattech-v]

maybe permanently weld it.. haha

 

[J101]

lorry pistons mah..ha ha ha....

n yeap..heard of feilo's gbox nowadays oso....darn it..sum more got marking kenot open 1..hehehehehhe