DOHC b16a VTEC

What is better, a b16a or a b18c? I think that the b16 is better even though the b18 is a more powerful engine because it likes to rev higher and stay in the powerband much longer than the b18. But the b16 lacks torque cause the b18 is bigger.

B00ST2nR

Umm... The b16a's Redline is 8000rpm and the b18c1's redline is 8100rpm, so its pretty obvious that they BOTH like to rev high, not just the b16a. The b18c1 outputs more power and torque. On the average, the b18c1 outputs more than 30 lbs of Torque more than the b16 throughout the whole powerband.

As for staying in the powerband.... that varies with mods and the tranny. If the tranny is close and drops close within each gear, its easier for the rev to drop down and stay in the powerband...


b18c!

wickedxboi

what about a b18c with a b16a tranny since the gears are shorter?

B00ST2nR

Ah yes. People do that. Shorter gears for faster acceleration. The b16a or Civic Si gears are very close to Type-R gears. The GS-R Gears are a bit longer. If you swap in a ITR or Si Tranny into a GS-R, it'll have faster acceleration, but your revs will also be higher than before.

Also, you can run out of room or gears for your top speed. My friend's 2000 Civic Si (Bone Stock) can hit 134mph. He can't pass it. As for me, I can goto 150mph. Thats about the only advantage it has.

If you go Turbo however, longer gear is better...

samagon

just switch an ITR final gear into a GSR tranny.

FD is ~4.4 in GSR, and ~4.75 in ITR. put in LSD while you are doing that as well.

edit: the reason I say this, is because the gear changes in the GSR motor are suited to the GSR powerband, so if you go with that, wouldn't you want a tranny that is suited to the powerband? plus, if you put in the ITR FD, you get quicker accel too.


[Modified by samagon, 12:57 AM 6/1/2002]

threatcon13

why would your revs be any higher when you swap an SI tranny into a GSR. the SI has a lower top speed due to its lack of torque and minimal difference in horsepower...i dont think that its the gearing that causes this. and please explain why longer gearing is better for turbo. its an urban legend that most people have sucked up wholeheartedly..yet still have not heard a reasonable explanation for this.

threatcon13

to answer your original question b20 owns all. no replacement for displacement,as the old saying goes.

B00ST2nR

With Shorter gears (which means the gears are larger), the rpm will be higher. In other words, if you go 80mph with an Si gear, you'll be at 4300rpm or so. With the GS-R Tranny, you'll be at 4000rpm.

As for the longer gear and turbo thing, I heard its because the turbo gets to spool a longer time. With longer gears, it can reach more mph in each gear.

B00ST2nR

yes yes.... we all know the b20 is the strongest, but he was specifically talkin about b16's and b18's...

threatcon13

yes yes...and look at the post topic so just answerin his original question.

threatcon13

alright...i misunderstood your first quote regarding the gearing. I thought u meant revving higher up for some reason ie. 8100(its late)...and a final drive should cure that problem. your second explanation however, i will have to post a rebuttal. staying in boost longer? what good does that do if youre still in first gear? if you get through the gears quicker youll reach your ET quicker period...second if you are power shifting you will be in boost the whole time regardless, which backs up point one.

MyIntegra2Fast

b20/vtec way to go..just put on in my car..pulls harder than my gsr ever though about doing!! liek the guy said "no replacement for displacement" b20/vtec all the way!

owen_the_soyboy

powerband of a B20/ITR vtec head is a lot broader than the other setups. MUCH more torque across the board.
there is no other way to get a monster unless you start employing race-only parts... ITB's, Race Porting, all out Race cams, etc.

B00ST2nR

I personally don't know all the details of this LONGER gear plus Boost theory, but from reading all the posts on Honda-Tech, I learned that longer gears help out with boost...

threatcon13

that is cool..i just wanted to know your reasoning for thinking that way

MyIntegra2Fast

ya i am using a b20bottom with a b16a head with rebuilt with new valve seals, type
R valves, dual valve train and retainers..and a type r intake manifold..pulls real nice!

The Rob

My replacement for displacement is the turbo in the basement.

rodimus

you live in so cal...
smogging the B20 aka crvtec might be a b1tch...

StinkyTofu

My reasoning behind it is because with a turbo set up + shorter gearing, your car will rev alot faster. With an itr tranny you'll be shifting at redline and landing at a high rpm, then you will have to shift soon again because of the turbo. With turbo you'll just spend too much time shifting.

Now with a LS tranny, the gears are longer. The car won't rev as fast, but you can stay in gear longer and spend more time in the beefy part of your powerband. Its kind of like a bicycle. You can get a fast start in the shortest gear but it won't last long. If each upshift is relatively close to the previous, then it wouldn't be very efficient. Instead get something a little longer so you won't kill your legs and go a farther distance per cycle.

Unlike all-motor, turbos don't need to be revved high to make power. Shorter gears work good for n/a cars cause they don't make much power. Thats just my "theory".

blufke

how good would an ls tranny be for a b20 without vtec. i would like to get a b20 and eventually boost it. i also want nice highway cruising rpms. but ive read that for racing the ls tranny sucks even with like 200whp. thoughts or experience?

broke1

i would try to get a gsr tranny. also i've been hearing a lot about people putting the ls 5th into their b16 tannys....?

SlowazzGSR

Ya, my friend has amn ls 5th gear in his b16 trany. Lowered 5th gear rpms by about 400 rpms when cruising at 70. Talk about saving gas.

cyrk007

b20 takes all.. but to answer the q b18 definately.. again...NRFD and cmon.. b16 is good and all.. but there lies more potential in the b18

Stop the Beast

An LS ranny woulde be good with a b20 cause the powerband is lower and much torquier, much like a turbo, an b20 will make more torque at 4500 than a b16 at any point.

threatcon13

another person who has no idea what hes talking about.