B18c or B16a?

[kerim]

i am looking at turboing my DC2 Vtir. and i got told 2 get a bi6a head instead of the stock b18c due to more compression or something along those lines?
what do u guys think? what benefits would i get?

[Professional]

For the turbo setup, lower compression is better.

[Q_ball]

http://www.ozhonda.com/forum/showthread.php?t=28462&highlight=b18c
b18c

http://www.ozhonda.com/forum/showthread.php?t=40237&highlight=b16a
b16a

Try those threads man, a bit of info about turbo applications on both.
I know turbo b18b/c goes off from personal experience :)

[Q_ball]

Professional, not entirely true..
So long as the tune is good, high comp and boost will result in awesome results.
But with anything, bad tune and boost = bye bye motor :)

[jimmeh]

Professional, not entirely true..
So long as the tune is good, high comp and boost will result in awesome results.
But with anything, bad tune and boost = bye bye motor :)
bad tune with any car = bye bye motor

[kerim]

so you guys rekon i should stay with the B18c

[pornstar]

Kerim, dont waste your money, turbo the b18c as it is

[wynode]

i am looking at turboing my DC2 Vtir. and i got told 2 get a bi6a head instead of the stock b18c due to more compression or something along those lines?
what do u guys think? what benefits would i get?
Just putting the b16a head on your b18c will actually loose compression unelss you change pistons.

Just boost your motor as is!

[jimmeh]

Dont get rid of you b18c head as they flow better than the b16 at higher rpm.

[kerim]

thanks guys for your quick response and help,
i guess ill stick with the B18C

[edw-R]

Tell us the result !!

[EGB18CT]

stick to the b18..thats what im doing... look at a lot of people in the states most run b18c's

[Professional]

Low comp. + turbo + good tuning and High comp. + turbo + good tuning

Which combination will produce max. power?

[T-onedc2]

Too lower comp gives poor off boost response, too high comp will break your engine, there's a compromise to be found.

[saxman]

high comp + turbo = more power than low comp + turbo if all other things remain constant

[Professional]

High compression = 11+
Low compression = around 9-10

Which compression setting will be suitable for turbo set up?

[saxman]

both are potentially suitable for a turbo set up(with in reason)... There's absolutely no reason you couldn't run a 11-12:1 comp ratio with a turbo set up, as long as you have an appropriate set up... correct pistons(most high comp pistons are made of a different material than low comp turbo pistons... so you have to be careful there), proper fueling/octane rating, good intercooling, and most importantly very very good tuning.

also, keep in mind, most people think of low comp as 9 or lower generally...

[jimmeh]

Too lower comp gives poor off boost response, too high comp will break your engine, there's a compromise to be found.
stop reading stuff written by net mechanics

[fatboyz39]

with high comp motors and turbo tuning is vital. Its all in the tuning. Just take a look at AH_HUH car...type R boosted with stock internals it made 200kw atw +, thats got 11.5 compression.

Talk to your tuner and see whether they can tune it, if they can't find a new tuner!.

[kraiye]

as far as i'm aware a lot of those in the states that run b18c's use b16a heads cause apparently they flow better and give lower compression. the lower compression basically allows you to run more boost. i'm not very turbonetically educated but i have read a bit and it seems many people go for the b16a head for higher boost applications.
but like i said, i've never actually done it so try and research off those that have, maybe check some yank sites out too :)

[saxman]

running a lower comp ratio does allow you to safely run higher boost, however, you're getting less hp per psi, less ftlbs per psi, poorer response on and off turbo, less low down torque, etc


people have to run higher psi levels to catch back up with the higher comp set ups at a lower psi

[Professional]

Last question:
High compression + low boost + good tuning
Low compression + high boost + good tuning

Which combination will produce more power?

[Q_ball]

^Considering all factors are constant - as in good tune = good tune (same tuner), then they'd be equal to one another.
You're basically sacrificing one or the other to achieve the same goal.

[saxman]

^Considering all factors are constant - as in good tune = good tune (same tuner), then they'd be equal to one another.
You're basically sacrificing one or the other to achieve the same goal.
assuming the same effective compression is achieved
(i.e. a 10 psi boost on an 11:1 comp ratio versus a 15 psi boost on a 9:1 comp ratio) then yes, the final power may be the same, but the higher comp set up is still going to have the benefit of better off boost power, quicker spool, and better throttle response

[string]

assuming the same effective compression is achieved
(i.e. a 10 psi boost on an 11:1 comp ratio versus a 15 psi boost on a 9:1 comp ratio) then yes, the final power may be the same, but the higher comp set up is still going to have the benefit of better off boost power, quicker spool, and better throttle response
I hope you mean quicker spool as in boost vs time, not boost vs rpm, since a higher compression ratio does not yield any more exhaust gases.

[saxman]

faster off boost reponse=quicker acceleration=less lag/quicker spool time wise


you're correct that vs rpm, it's not going to make a difference, you'll just get to said rpm sooner so percieved lag is reduced

[todaek9]

not just what ever compression...u need to choose the right cams, right piston, right tb, right intake, right turbo, right rods...there is just too many things to consider if you want to have hi-boost + high HP....

but if you want to go for a simple setup, just get a turbo kit by Apexi...if hardcore, kkk-series...

[fatboyz39]

i'd rather have response. So standard compression/turbo and good tuning.

[Twincam16]

Farknell, everybody is going in circles.

If you want lag and that "ill just keep it at 3500rpm, and smoke this foo", then lower your compression for better peak power, sacrificing low down torque. As Saxman pointed, you can easily run higher boost, but you will lose low down driveability, oh, and torque-steer is not your friend.

If you want quicker off line acceleration, better throttle response, at the 'higher' risk of detonation from poor tuning, without needing to run high psi. Then leave compression high. In turn, its reccomend upgrading valvetrain to something that can handle higher comp with boost. ECU & Fuel supply are A MUST - do not go el-cheapo here mofo's, you will get slapped. Most importantly, a good tune from somebody that knows what they are doing. Do it once, do it right.

You will also need love and support from your garage, a big bucket of maltesers, and a few kegs of your favorite beer at arms reach. DO NOT SACRIFICE ON THE BEER!!!! YOU WILL BE SLAPPED!