Turbo + VTEC ?

[xiang]

Hi everyone..
A friend of mine mentioned to me that having turbo and vtec is something that is completely pointless.

I saw a comment mentioning that, that was bullcrap.

I'd think that having VTEC and turbo would be a benifit would it not?
It's just something thats been on my mind and just want to find out the answer.

Thanks in advance.

[Kandy]

This is a good article

http://www.ozhonda.com/forum/showthread.php?t=41653

[tinkerbell]

there is a lot of *discussion* in here...

it is tedious to wqade through though!

you can see my opinion is quite clear...

http://www.ozhonda.com/forum/showthread.php?t=28930

[xiang]

thank you thank you! will read.

[hotboxcivic]

tunning is important, alot of people just wack a turbo on and end of story. most have trouble with traction because of VTEC, but if done proper there are huge benefits.

[Q_ball]

turbo on most fwd will = traction probs!
powerwise...turbo + vtec is like gods gift to man!
its unreal once tuned right!!
like wat tinkerbell has said, theres a lot in the forums about this, jst search around and skim through the material (i say skim cause theres a lot of SHIT) out there :p

[Mr.Pen]

umm quetsion...

isnt vtec higher rpm range, so how does vtec help a turbo?

at the end of the day vtec isnt much different to the head setup on an neo engine. and non-neo turbo engines make better power than the neo turbo series...

not tring to stir shit, just interested if the gains vtec give to a turbo, say something like gt2510 (300hp)

[Q_ball]

search bud! covered many times man :)

http://ozhonda.com/forum/search.php?searchid=590307

try these threads!

[Slow96GSR]

The turbo is a compressor. The intake system can only flow so much until it reaches its peak flow. VTEC open the valves a little more which improves flow allowing the air/fuel mixture to get in there faster. Not really more but kind of. It only has a short while to get air in before the valves close, so the turbo needs the higher lift, longer duration and right a/f ratio to make the most power. This is where the tune comes in. Too long of a duration and the a/f comes back out the open valves. Too much lift and you brake/damage a valve spring or in a 0 clearance motor if it doesn't close all the way or fast enough bang, bent valve or damaged piston. A/F is a big issue, you need that right or you get all sorts of problems, running rich will wash the rings and you'll lose compression. Running lean will cause detonation ( http://www.misterfixit.com/deton.htm). Read that to understand. Hope all that helps!

[saxman]

Anyone that says the turbos and vtec combined are pointless, etc, obviously don't have any idea about them.

VTEC is simply something that allows you to run two different cam profiles to allow more torque down low and more hp up high. It simply helps flow. There's absolutely nothing about it that will counteract how a turbo works, etc.

If someone is questioning the gains a turbo vtec motor would make compared to say the same motor, without vtec, simply look at how vtec engagement is determined on a turbo motor. A dyno pull is usually done only on the low cam, and only on the high cam, and they're overlayed. You can clearly see where the high cam starts making more power than the low cam... which is about where vtec engagement is set.

[simbadda54]

Probs start doing burnouts once u hit vtec and torque steer urself into a gutter

[tinkerbell]

Probs start doing burnouts once u hit vtec and torque steer urself into a gutter

you guys saying these kinda things have obviously never driven a high powered normally aspirated VTEC engine...

[simbadda54]

We are talking about turbo'd vtec mate. NA = naturally aspirated

[tinkerbell]

high powered NA do burnouts when it hits VTEC too.

Removed as comment were inflamitory

[Zdster]

Careful you two.


Please stay on topic. We are discussing how turbo's interact with vtec.

[tinkerbell]

Please stay on topic. We are discussing how turbo's interact with vtec.

yeah, not how VTEC interacts with the road... ;)

[simbadda54]

I was saying once they both kick it it would be kinda undriveable. Wasnt talking about vtec by itself at all.

[tinkerbell]

I was saying once they both kick it it would be kinda undriveable. Wasnt talking about vtec by itself at all.

i doubt anyone would want their turbo to coming on boost at the same time VTEC engages...

in most cases, the turbo would be on boost well before the VTEC is set to engage...

[saxman]

with a properly tuned set up, you're not going to notice much power difference when vtec engages... if you're getting a sudden burst in power at vtec, your engagement point is wrong. The car should accelerate faster, but there shouldn't be a sudden boost in power.


further more, the surge in power from a turbo is like a kick in the face compared to the pinch of vtec. They're no where near comparable.

[SINISTR]

im not an expert on this, nor do I really appreciate Vtec Turbo cars as Im one of those people tho believe Honda built Vtec for the purpose of being a sporty NA car not to be turbo'd but thats beside the point... anyway.

I think having a turbo on a Vtec car is like having a turbo car and getting an aftermarket set of cams - when properly tuned it allows the car to breathe better and produce more power.

[simbadda54]

Ur tegs doing burnouts with vtec engagement? B20r's are from DA's arent they?

[tinkerbell]

aw, sorry! i thought this thread was actually in one of the technical forums!

i didnt realise it was in the n00b forum, i am sorry simbadda54! i have been unfairly harsh on you!

no - the B20B is out of a CRV, with a VTEC head from a CRX... yes, i had wheel spin in 2nd and 3rd if i was too agressive with the throttle, but my VTEC was set quite low at 4300rpm...

DA's had B18A engine...

/end off topic

[saxman]

aw, sorry! i thought this thread was actually in one of the technical forums!

i didnt realise it was in the n00b forum, i am sorry simbadda54! i have been unfairly harsh on you!

no - the B20B is out of a CRV, with a VTEC head from a CRX... yes, i had wheel spin in 2nd and 3rd if i was too agressive with the throttle, but my VTEC was set quite low at 4300rpm...

DA's had B18A engine...

/end off topic
that's from a motor with torque though, not because of the magical powers of vtec

[tinkerbell]

is that a statement or a question?

i surely do not need to describe to you what happens to a torque curve when VTEC engages?

it *jumps* up...

at this point, where torque *jumps*, wheelspin is more likely...

therefore there is no *magical power of VTEC*, it is actually just the amazing effect of increased torque (due almost entirely to VTEC)...

[SINISTR]

But the B20 block - being from a CRV is mainly built for 'torque' comming from a 4x4 - hence the increased Nm compared to a normal B16 or B18 motor. I think thats what SAXMAN was trying to say.

[tinkerbell]

why are we even talking about B20VTEC's?

[Zdster]

No idea, but I think this topic has been answered.


Turbo + Vtec is fine and work on to different sections of the engine. If anyone has anything else to add please PM me (and I will open the thread back up) otherwise thanks all for the responses.