My 2L B-Series N/A Project

[chris2000]

Eh? the block died already? I dropped by to pick up some stuff and it was not in yet, now it's gone already?

My condolences, chris... well, what might have been.

Good luck in your MME engine.

Just curious... you're still using the stock S80C with the 4.785 FD? Or changed already? no need to let me know the ratios, just wondering if you got them changed.

Yup, when you drop by, it was already preparing to assemble. but after assemble and before start up saw water leak through the block! hai...

I'm not running type-r gearbox. Ratio all change except for 2nd is OEM. If you gear ratio let me know. Spoon ratio is too close for road use and too close for 1.8cc-2.0cc.

 

[shiroitenshi]

Yup, when you drop by, it was already preparing to assemble. but after assemble and before start up saw water leak through the block! hai...

I'm not running type-r gearbox. Ratio all change except for 2nd is OEM. If you gear ratio let me know. Spoon ratio is too close for road use and too close for 1.8cc-2.0cc.

Yeah.. I know.. someone here is using it already. Spoons are really close. I guess it was meant for their 11K b16B. Not a good option if you're rev limited to 8-9K.

Cruising at 5th is with 4.5FD is 4K+ at 100kmh. :P

What you mean by "you gear" ratio? I assume it's a typo.

 

[chris2000]

no laaa... i mean my block die like chris block... hairline crack at the liner...

Bro, you want to sell your crack liner block to me as besi buruk?? :angel_smile:

Seriously, if it is the liner crack only, please call me or pm me. Wanna R&D a bit.

 

[shiroitenshi]

Bro, you want to sell your crack liner block to me as besi buruk?? :angel_smile:

Seriously, if it is the liner crack only, please call me or pm me. Wanna R&D a bit.

Wah.. so fast making a move already.. (O_o)

 

[chris2000]

Yeah.. I know.. someone here is using it already. Spoons are really close. I guess it was meant for their 11K b16B. Not a good option if you're rev limited to 8-9K.

Cruising at 5th is with 4.5FD is 4K+ at 100kmh. :P

What you mean by "you gear" ratio? I assume it's a typo.

I meant if you need gear ratio let me know.

I meant Spoon ratio too close is because at gear change the revs drop too little about 1400-1500rpm(so little coz 1.6 no torque and need to keep rev high). You are right, ratio was intended for short stroke B16B revving to 11k rpm .

For both road and race use with good torque, ideal is a ratio with gear change rev drops about 1800-2000rpm. This saves a little gear change time.

 

[shiroitenshi]

I meant if you need gear ratio let me know.

I meant Spoon ratio too close is because at gear change the revs drop too little about 1400-1500rpm(so little coz 1.6 no torque and need to keep rev high). You are right, ratio was intended for short stroke B16B revving to 11k rpm .

For both road and race use with good torque, ideal is a ratio with gear change rev drops about 1800-2000rpm. This saves a little gear change time.

Thanks for the tip. Another way I think would be playing with sub 4.4 ratio FDs, but that would be counter intuitive, wouldn't it?

 

[hattech-v]

i think spoon not too close compared to kaaz or ats (their original spec...)
spoon i think is good for big cc.. while ats/kaaz good for 1.6

 

[chris2000]

i think spoon not too close compared to kaaz or ats (their original spec...)
spoon i think is good for big cc.. while ats/kaaz good for 1.6

Nope..

Spoon 3-5 Ratio
3rd-1.591 3rd-4th RPM drop 1660rpm
4th-1.280 4th -5th Rpm drop 1640rpm
5th-1.033

ATS 3-5 Ratio
3rd-1.652 3rd-4th Rpm drop 1770rpm
4th-1.308 4th-5th Rpm drop 1780rpm
5th-1.033

KAAZ copy Spoon ratio so they are similar.

If you ratio itself ATS is indeed closer which mean the 3rd and 4th gear has less top speed.

But what i meant Spoon is too close coz at gear change, the rpm only drop 1600+rpm which requires you to do more gear shift and change.

Where else, ATS speed on each gear is slightly lower but rpm drop is almost 1800rpm which allow you to rev each gear longer before gear change.

I found a custom gear set from USA which provide a little more speed than Spoon and rev drop about 1950-2000rpm which is ideal for road cars and powerful track car. Should be testing them soon in July :regular_smile:

 

[shiroitenshi]

Chris, the ratios based on what FD?

The FD changes the rev drop numbers a little.. I think spoon uses something like 4.4 or higher for their FD in their 11k rpm B16B, because if you saw the vid of the test, it looked as if the speed isn't that high, and the rev drop is somewhere like 2K, I think.

Replicating that setup on a 9K limited B series did not get good results, though mix and matching helped a bit after that.

And one more thing that made me go (O_o)
The first and 2nd are like 2.XXX, and 2.1XX? (I'm not sure the exact numbers, but I think it was a bit extreme.. what kind of FD they expect us to use?) 4.9/their highest ratio? That would seriously kill speed on a 8-9K rpm limited car. (which may be a bad or a good thing.. I'm no track driver!)

Personal thought is, it seemed like they made it especially for their 11K rpm B16B.

 

[chris2000]

As far as i know and tested, FD does not affect rpm drop on each gear. FD just alter the entire gear ratio speed per gear.

It is the gear ratio that affect each indivual rpm drop and speed.

Stock EK9

3rd-1.458 3rd-4th rpm drop 2050rpm
4th-1.107 4th-5th rpm drop 2000rpm
5th-0.848

 

[shiroitenshi]

As far as i know and tested, FD does not affect rpm drop on each gear. FD just alter the entire gear ratio speed per gear.

It is the gear ratio that affect each indivual rpm drop and speed.

Stock EK9

3rd-1.458 3rd-4th rpm drop 2050rpm
4th-1.107 4th-5th rpm drop 2000rpm
5th-0.848

Hmm.. actually it does in my head.. at least in theory it does, after all, looking at the speed vs rpm chart here, its obvious that as speed climbs, rev drops become more exaggerated. Naturally we won't see much difference on 8-9K rpm engines, but I think it should be quite apparent on an 11K spoon engine.

Edit.. I think i interpret it wrong, I think you're right that FD does not affect rev drop points, but rather how high the engine is revving that affects the rev drop points. Opps on my part... :P

Which reminds me of something, that on low speed shifts, the 3rd gear rev drop is only like 1K? So in a way, how high the rpm during the point of shifting affects how much rpm drop.

Chart for a Y21 g/box if the car has enough torque to actually push the gears up to those speeds.

Of course, this is theory, and in my head, I also think that drag co-efficiency (Cd) and momentum would play a part in affecting real life rev drop points, which is why as speed climbs, there are differences in theory and practical applications.

During off throttle/shifting time, does the car still accelerate due to momentum, or does it start to decrease speed due to drag?

Man, got my head in a bind there.

 

[evoX2]

bro shiro, after checking with the gear calc, i also found that final drive wont affect rpm drop during gear change, only the top speed of each gear. how come higher fd give lower top speed for each gear, then mind to explain why 4.75 is better than 4.4 fd? i'm confuss.... thx.....

 

[shiroitenshi]

bro shiro, after checking with the gear calc, i also found that final drive wont affect rpm drop during gear change, only the top speed of each gear. how come higher fd give lower top speed for each gear, then mind to explain why 4.75 is better than 4.4 fd? i'm confuss.... thx.....

Yeah.. I noticed it when I put in the numbers as well.. I remembered last time I noticed that rev drop numbers were different depending gearsets, and I thought it was the FD, but apparently it isn't. It's where the engine rpm is at that affects it.. I make a mistake on this one.

Anyway, the 4.75 is better than 4.4 fd in terms of torque multiplication.

I think I explained to you earlier about using FD to reduce top speed, but get better torque. In a way, you reach that speed earlier, because what the FD does is doing torque multiplication. If you have a mountain bike, motorbike or geared bicycle, I think easiest to show this point. The rear sprocket, in this case, is your final drive. the bigger the rear sprocket is, the lighter to pedal/faster acceleration, but you sacrifice the top speed achievable on each gear.. To get around it, you either pedal faster or rev it higher on the motorbike (more rpm).

Try it, and it should be clear to you.

 

[chris2000]

Shiro you are right with rev drops as rpm change climb.

My info provided were all based on a 8500rpm limit gearchange where most road cars will go or higher cc race engine.

So for the very close Spoon ratio, at 8500rpm limit the rev drop was indeed about 1600rpm. But if you take the rev up on a B16B like how Spoon does it at 11krpm, the rpm drop on gear change is 2150rpm. And we all know not many locally build engine can take it to 11k rpm and the highest i ever heard in malaysia was 10.5k rpm and the result was a complete overhaul after every race or spin a bearing at 10.5k rpm!!

So thats why i'm toying around the idea of searching a ratio that have rpm drop in the region of 1900-2000rpm on a 8500rpm and 2000-2100rpm drop on 9000rpm and 2100-2200rpm drop on 9500rpm which is about where most cars can rev to and rpm drop is at the level where Spoon intended it to be at 11k rpm. :)

 

[evoX2]

ok, i get what u mean now. but will a 4.75fd be harder to launch comparing to a 4.4fd due to the extra torque?

 

[shiroitenshi]

ok, i get what u mean now. but will a 4.75fd be harder to launch comparing to a 4.4fd due to the extra torque?

Lauching, you have to ask hattech.. he's a consistent launcher. Even after making a mistake doesn't kill his tempo. :P I saw him launch his car last time, and he can do it consistently.. chalk it up to his experience.

I don't think 4.75fd will be harder to launch.. afterall, the ITR g/box with the 4.785 ratio also uses the same 1st gear ratio your car is using. It increases torque, but not too extreme, futhermore your 2nd is 1.9, as opposed to the stock ITR at 2.105

But like my friend told you, it is cheaper in the long run to buy a ITR with a 4.785, since you get the ratio and the LSD for a price that's significantly lower than putting in the parts one by one.

 

[shiroitenshi]

Shiro you are right with rev drops as rpm change climb.

My info provided were all based on a 8500rpm limit gearchange where most road cars will go or higher cc race engine.

So for the very close Spoon ratio, at 8500rpm limit the rev drop was indeed about 1600rpm. But if you take the rev up on a B16B like how Spoon does it at 11krpm, the rpm drop on gear change is 2150rpm. And we all know not many locally build engine can take it to 11k rpm and the highest i ever heard in malaysia was 10.5k rpm and the result was a complete overhaul after every race or spin a bearing at 10.5k rpm!!

So thats why i'm toying around the idea of searching a ratio that have rpm drop in the region of 1900-2000rpm on a 8500rpm and 2000-2100rpm drop on 9000rpm and 2100-2200rpm drop on 9500rpm which is about where most cars can rev to and rpm drop is at the level where Spoon intended it to be at 11k rpm. :)

Well.. in that case, I'm thinking of mixing oem gear ratios.

I wonder if the layshaft on the Y1 would fit in a Y21? The gearbox is rare though so I'm probably dumping the idea.

I'll post the rest later.. makan hour, after this work, and after that work. not going to be in front of the computer for the rest of the day. Post the rest later. Got some questions about my planned ratios.

 

[Blue Little Lorry]

Chris2000, Where did you get the DC sports 4-1 from and how much is it ?

 

[hattech-v]

chris, u rite spoon ratio is closer compared to ats/kaaz
actually what make it closer is the closer the number from each individual gear will make the rpm drop lesser...
for me, gear ratio combination is the most important thing for drag or even for track....
fd does not effect the individual ratio/rpm instead the speed for individual gear...
about what final drive can help u is all about the torque multiplication...
u can find lots of info here...

http://www.team-integra.net/sections/articles/showArticle.asp?ArticleID=707

 

[evoX2]

chris, u rite spoon ratio is closer compared to ats/kaaz
actually what make it closer is the closer the number from each individual gear will make the rpm drop lesser...
for me, gear ratio combination is the most important thing for drag or even for track....
fd does not effect the individual ratio/rpm instead the speed for individual gear...
about what final drive can help u is all about the torque multiplication...
u can find lots of info here...

http://www.team-integra.net/sections/articles/showArticle.asp?ArticleID=707

thanks for the info. now i understand why final drive is so important. :_:

hattech, will it be harder to launch with the extra torque?