crvtec vs. ls/vtec

[darkerdayz]

i have been doing my research on both of these engines and there is something i was wondering. from what i've read and researched, the b20 block is basically a b18b block that has been bored to 84mm. now, i was planing on building a crvtec but still resleeving the cylindars to handle high boost (~20 psi). but now i'm wondering, because the b18b block is much cheaper than the b20, would it make more sense to buy the b18b block and then resleeve and boring it to 84mm? that way i would also be able to have the tranny from the b18b (taller gears = better turbo spool).

any help would be greatly appreciated.

[SenseiAccord]

in my opinion... the ls/vtec is basically a GSR motor. thats why ls/vtec wasnt made by honda b/c their ls'vtec is a GSR motor. That way the motor is meant to last a long time with the correct features. It may sacrifice power but it will last u a long time.

[civickiller]

why would you think that a ls tranny helps a turbo spool better ? plz try to explain this.

i wouldnt bore it to 84, i would go 83 because if you mess up and melt a piston then you would have room to bore it out alittle, but at 84mm if you have to bore it gets unsafe to boost high

[boosted331]

Originally Posted by darkerdayz

that way i would also be able to have the tranny from the b18b (taller gears = better turbo spool)

Go talk to whoever told you that and beat the fuck out of them with a big stick. Your car will be slower, MUCH slower with an LS tranny than it would with the GSR or ITR tranny, no ifs, ands, or buts. If you're sleeving the motor, go with whatever you can get cheaper. They use the exact same crank, so it doesn't matter which one you use.

[darkerdayz]

Originally Posted by boosted331

Go talk to whoever told you that and beat the fuck out of them with a big stick. Your car will be slower, MUCH slower with an LS tranny than it would with the GSR or ITR tranny, no ifs, ands, or buts. If you're sleeving the motor, go with whatever you can get cheaper. They use the exact same crank, so it doesn't matter which one you use.

http://www.automotiveforums.com/vbulletin/t127184.html
read the 3rd post on that thread. pretty much everyone agrees that the longer ratios are better for turbo. if you can give me words as to otherwise, please do.

thanks.

ok, i just read through the posts again and i saw what you were saying about longer gears vs. shorter gears (ls vs. dsm vs. rx-7). so may i ask, what would you recomend for a crx looking to hit 11's posible high 10's?

[M@St3R_D]

The reason why an LS tranny is better for turbo is, as you mentioned, the longer gear ratio.... Why??? Because the longer gear ratio will allow your turbo to stay longer in the PEAK HP of your motor so you get power for a longer period of time.... Of course, you will be slower on the start than a GSR and ITR tranny because the shorter gear ration will allow your turbo to reach PEAK HP of your motor faster but you stay a shorter period of time in this PEAK HP.... So it will take less than 2 sec for the LS tranny to overtake the GSR tranny.... It's a matter of what you wanna do.... Both are good for a given situation.... But I would go for an LS tranny.... My opinion

[M@St3R_D]

ok, i just read through the posts again and i saw what you were saying about longer gears vs. shorter gears (ls vs. dsm vs. rx-7). so may i ask, what would you recomend for a crx looking to hit 11's posible high 10's?

Darkerdayz, as I said in previous reply, shorter gear will help you getting into your PEAK HP faster so.... For 1/4 where the acceleration is what you need the most, I would go with shorter gear.... Correct me if I'm wrong....

[civickiller]

what kind of tranny you want depends on alot of factors, like tire size, how fast you trap in the 1/4 and what gear your in at what rpm. you dont really want to be hitting 5th gear in teh 1/4 so if you are hitting 5th then you gotta eitehr get bigger tires or change to a longer tranny.

alot of people like the gsr tranny because its in the middle between the b16 and the ls. and the gsr usually is the best because it doesnt top out like the b16 but isnt too long like the ls.

also with the ls engine it doesnt go all the way up to 8200 so you gotta shift early which means you will go through the gears fast so therefore toping out fast. lots of factors. but also if your barely toping out the b16 tranny, you might think about running bigger slick because that will make the tranny alittel longer and then it might be perfect. lots of factors

[boosted331]

GSR/ITR/B16 trans have numerically higher gears, numerically higher gears means more torque/horsepower multiplication to the ground. Higher torque/horsepower multiplication means more power to the ground, quicker acceleration.

If you still think the LS trans makes your car faster, you're wrong. There's nothing else to say. Go call up ANYBODY notable who has built hondas, and they will tell you you're dead wrong on the LS trans issue. It really irritates me when people who have never even built a fast honda before, and who don't know there is no difference between an 84MM sleeved B18 and an 84MM sleeved B20 try and say whats right or wrong with transmission gearing.

[boosted331]

Originally Posted by M@St3R_D

Darkerdayz, as I said in previous reply, shorter gear will help you getting into your PEAK HP faster so.... For 1/4 where the acceleration is what you need the most, I would go with shorter gear.... Correct me if I'm wrong....

I didn't even see this, holy fuck i'm shoked. You have basically ackowledged right here that the previous post you made is wrong. Shorter gearing makes for quicker acceleration. So what the hell do you want to run the LS trans for? What are you building your car for if not quicker acceleration? And don't you dare say top end, because an LS trans with a typical 23" tire and an 8500 RPM rev limit has the top end for 190 mph in 5th, which no idiot in a honda will ever do. A b16/ITR trans w/8500 rev limit is solid to about 155, and a GSR with an 8500 rev limit will do 170.

[DeleriousZ]

ermm.. well if you think about it.. would you rather stay in your 'peak hp' range for longer.. or going through the gears quicker, accellerating faster.. don't you think that if you were in your 'peak hp' longer, you would be taking longer to accellerate?

[civickiller]

Originally Posted by boosted331

GSR/ITR/B16 trans have numerically higher gears, numerically higher gears means more torque/horsepower multiplication to the ground. Higher torque/horsepower multiplication means more power to the ground, quicker acceleration.

that statement is wrong, so what yoru saying is that a b16 with a b16 trans will put more power to the ground then with an ls trans, i dont think so. you will reach peak hp faster and go through it faster with a shorter tranny but you wont be putting more power to the ground. because no matter what you do your b16 will put down 160hp no matter what the tranny is. its more of how long it take to reach and go through the power band to be able to shift to the next gear.

ok alittle example for these people who are fond of there ls trannys, would you want to go from 120hp@4,000 to 160hp@7800 in 4 seconds with the ls or would you rather go through that in 2 seconds with the b16 (of course these arent real number i just made them up but it still situation still holds true).

now which one sounds faster ? see with the ls your going through the same power band as with the b16 trans but its just taking you longer to go through it, slower acceleration, do you want to accelerate slow ? i dont think so

[DeleriousZ]

that's exactly what i was trying to say lol

[M@St3R_D]

Well.... I have an LS tranny on my B18B turbo so boosted331, before saying that i don't have a fast honda please make sure your right.... And I eat a lot of gsr tranny turboed motor with it.... What you don't seem to understand is that being in peak hp for a longer period of time gives you more torque for a longer period of time.... think about it for 2 sec.... And the fact to be in peak hp longer doesn't mean the car isn't accelerating fast.... I don't feel like going over all that again so....

ermm.. well if you think about it.. would you rather stay in your 'peak hp' range for longer.. or going through the gears quicker, accellerating faster.. don't you think that if you were in your 'peak hp' longer, you would be taking longer to accellerate?

Your right about this but it's not only a matter of staying longer or shorter in your peak hp, it's a matter of going faster b/c you can maximize your speed by staying longer.... Take for example a bicycle.... when you start in the smoother gear, it's easier to reach a higher speed and that goes along with what you say but start on a harder gear, yeah you'll be much slower on acceleration but you'll get much more speed.... In a given moment, one rotation you'll make on the pedals on harder gear, will worth, ie, 10 rotations of the pedals on the smoother gear.... Longer gear in the end would accelerate more than shorter gear....

ok alittle example for these people who are fond of there ls trannys, would you want to go from 120hp@4,000 to 160hp@7800 in 4 seconds with the ls or would you rather go through that in 2 seconds with the b16

This sounds pretty simple said this way but this isn't necessarly the way it is.... I'll give you another example.... Take a 15" and 20" diameter wheels.... The smaller one will need a lot more rotation than the bigger to reach, ie, 60mph so if you make 7000rpm with smaller wheel, you will go, ie, 40mph and 7000rpm on bigger wheel will make, ie, 60mph.... Shorter gear will accelerate faster on start but will be slower on mid and top end coz you'll need to shift your gear earlier.... Longer gears will be slower on start but will go faster on mid and top end b/c you can keep going in your power band longer....Your right about saying that you will reach bigger hp faster on the start and that's what I said in my previous reply....

In fact nobody here is wrong about what tranny is better, the only difference is the way we use it so.... I agree with you guys but I'm not wrong either.... Some peeps like low end power, others like top end....etc. I think that the lack of comprehension about others interest is why this subject is always resurfacing....

[boosted331]

I give up. It's official. Everyone on this fucking board is retarded except for about 10 of you. I don't feel like elaborating right now, but if you think your LS tranny car is faster than a GSR tranny car you're plain ignorant.