Strange vtec problem ... anyone?

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22-09-2005, 12:44 AM
ken_wsw

Strange vtec problem ... anyone?

Hi ppz. Im new to this forum, and already have a big issue on my B18c.
Ive recently had my Toda spec C cams installed and currently running motec ecu. I have some weird problems with my vtec engagement.

problem 1:
I just had my car tuned, and vtec is set at 5800rpm. When i rev it up all the way to redline, i can only hear my vtec kicking in at 7000 rpm. The vtec 'sound' is delayed by almost 1200rpm.. has anyone had this problem before? what causes this to happen and how can i fix it?

problem 2:
When my vtec kicks in, I just cant feel the power at all.... the engine is screaming hard and it revs hard, but just not producing any power, by looking at my dyno graph... when after vtec kicks in, the power curve is not ascending as much as before vtec... does anyone know why?

problem 3:
I'm only peaking at 146hp dyno dynamics (shootout mode) which is a very low figure for the setup i have... any idea?

I would really appreciate if anyone can give me any advise or suggestion. Thanks.
22-09-2005, 12:52 AM
wynode

problem being?

More info PLEASE!
22-09-2005, 01:17 AM
ACTI0NMAN-1

i think he believes vtec is engaging at 7000 instead of 5800
22-09-2005, 01:24 AM
ken_wsw

I know my vtec does kick in at 5800rpm, but just dont understand why i can only hear it coming in at 7000rpm? Also when i say my vtec is not producing the right power, im talking abt from 5500 rpm onwards..... its strange isnt?
22-09-2005, 01:36 AM
wynode

You might have to speak to the tuner and / or give us a dyno read out
22-09-2005, 01:45 AM
ken_wsw

I'm just worried that it is some cams installation problem... if it is just a tuning problem, i wouldnt worry too much cuz im taking my car to another tuner tomorrow n hope he can fix the problem.
Anyone has the cam setting for toda spec C? mine is just at standard setting at the moment. I have a 2nd thought that could it be becoz i havent tune my cam timing yet, and this causes the vtec problem? but i was also told that even if cams are not set, it should run like a standard cam and shouldnt have any problems.
22-09-2005, 12:36 PM
xtercii

why don't you tell us more about your car's set up, that way ppl will have a clearer piciture of what it has and how it runs.
there are some knowledgable ppl in this forum who maybe able to help, but we need more info.
22-09-2005, 12:40 PM
gambate

are you using stock valve train?
22-09-2005, 12:49 PM
BLKCRX

Sounds about right to me... spec c cam's vtec cross over point is somewhere around 7000 rpm.. you might find your vtec is in fact set at 7000 not 5800rpm. Have someone else who’s experience with motec and the necessary hardware/ software to double check everything.

Regards James
22-09-2005, 02:14 PM
weezer

Can Motec control the secondary butterflies in the Intake Manifold? Perhaps what he hears as VTEC cross over might not be?
22-09-2005, 04:32 PM
ken_wsw

Thanks for urs participation...
I drive a EG civic with type R motor. Recently had my engine rebuilt:
Head ported/polished
Standard type R intake manifold/throttle body
Toda spec C cams
Spoon cams sprockets
CTR pistons
Compression ratio approx 12.0 to 12.3 (according to some website's calculation)
Sard fuel regulator
Motec ECU

Ive juz gone for another dyno tune this morning with a different tuner....no gains in HP / power curve. I've attached a dyno graph here so u guys can have a look. You will notice when vtec kicks in at ard 6000rpm, power curve is not ascending as how it should be.... have a look and u'll know what i mean.

My tuner was telling me that one of reason that caused losing power in vtec band is because my type R intake manifold is not sufficient enough... is that correct? cuz i always believe that type R manifold would be sufficient even for Toda C cams or other high lift cams. Another thing we could think of is my cams are not correctly set. could this be the case? if it's, im in big trouble, that means i have to rip my engine apart and re do the cams again which will prob me cost me another $1k??
22-09-2005, 04:42 PM
weezer

The ITR intake manifold is pretty good. i've seen cars make 140kw+ with ITR manifolds. Perhaps try a compression/leakdown test?
22-09-2005, 04:50 PM
ken_wsw

Compression n leak down test was done... everything seems fine.
23-09-2005, 12:10 PM
ProECU

It could be VERY possible the intake system including the charge pipe & manifold are a source of restriction. I'd suggest a ported intake manifold & tapered throttle body.

These wont however solve your current lack of power issue you describe.

I'd really like to see a a/f graph and a torque graph if you have them
23-09-2005, 01:31 PM
ken_wsw

Im also guessing it could be lack of compression...
but i have CTR pistons in B18c block, that should give me at least 11.8:1 or 12.0:1 in compression ratio. Head was shaved by 3 thou and block was decked by 5 thou. But i am only getting 225 psi for all 4 cylinders... does it sound abit low? cuz ive compared with another stock jap spec B18cR motor and he has got 250psi with all 4 cylinders. Anyone with similar setup can tell me what sort of compression reading u r gettin? thx!
p.s how much does it cost to port out the intake manifold?
23-09-2005, 03:03 PM
ProECU

could be anything
bad ring seal, cam phasing etc

I dont think you have enough static compression to maximise those cams.

have you played with cam gears?
23-09-2005, 05:28 PM
Weq

as long you have a good compression on all cylinders, i say the rings are fine. gauges will never be entirely accurate. have u tuned the cam gears? i didnt see the dyno graph? i was under the impression todac's needed plenty of revs behind them to make power.
23-09-2005, 08:20 PM
ken_wsw

james has the image of my dyno chart, which he will post it up soon when he's free... =) Cuz i dont know why this forum is not allowing me to upload any file....even i have decrease the size to below the limit.
23-09-2005, 10:58 PM
wynode

Quote:

Originally Posted by ken_wsw

james has the image of my dyno chart, which he will post it up soon when he's free... =) Cuz i dont know why this forum is not allowing me to upload any file....even i have decrease the size to below the limit.

email it to wynode @ ozhonda.com and I can upload it for you.
24-09-2005, 08:56 AM
jdmlvn

juz like my bros dc5r, the vtec kicks in at 5.5k rpm but u can hear the vtec at 6k rpm
24-09-2005, 09:36 AM
TODA AU

Quote:

Originally Posted by ken_wsw

Thanks for urs participation...
I drive a EG civic with type R motor. Recently had my engine rebuilt:
Head ported/polished
Standard type R intake manifold/throttle body
Toda spec C cams
Spoon cams sprockets
CTR pistons
Compression ratio approx 12.0 to 12.3 (according to some website's calculation)
Sard fuel regulator
Motec ECU

Ive juz gone for another dyno tune this morning with a different tuner....no gains in HP / power curve. I've attached a dyno graph here so u guys can have a look. You will notice when vtec kicks in at ard 6000rpm, power curve is not ascending as how it should be.... have a look and u'll know what i mean.

My tuner was telling me that one of reason that caused losing power in vtec band is because my type R intake manifold is not sufficient enough... is that correct? cuz i always believe that type R manifold would be sufficient even for Toda C cams or other high lift cams. Another thing we could think of is my cams are not correctly set. could this be the case? if it's, im in big trouble, that means i have to rip my engine apart and re do the cams again which will prob me cost me another $1k??

The following is probable:
Cam timing is incorrect.
Adjust with cam pulleys - correct setting data would have been included with your camshafts. If this is done wrong, power suffers.
Time to set correctly is approx 2hrs when already installed.
TDC guage, dial indicator & magnetic base are essential.
Vtec swap point is too low.
(Average swap for Spec C's in B-series is 7000+rpm)

Regarding intake manifold.
The std ITR manifold & std throttle are good to 240hp (engine)

Show picture of graph to better explain issue.
Other concerns can be mixtures, ignition timing & exhaust system.
24-09-2005, 02:45 PM
ken_wsw

If toda C's is only good at swapping vtec over 7000 rpm... and my engine can only rev up to 9000rpm (stock retainers), am i benefiting the max power of the cams? would i be able to set the peak power point at 8800rpm? so that means i only have 2000 rpm of vtec zone in every gear to play with.... enuff?
24-09-2005, 09:39 PM
Weq

the cam is a bit to wild for ur needs IMO. spec b's would of been better to 9000rpm... that said, i dont have experience with them irl.
25-09-2005, 12:12 PM
BLKCRX

Dyno Graph as Requested
http://blkcrx.hondata.com.au/blkcrx/dyno/CIMG0268.JPG

Regards James
25-09-2005, 12:17 PM
ken_wsw

Thanks james for hosting the dyno graph for me. =) So guys, the above is my dyno graph with toda C cams, as u can see vtec didnt come in strong at all. :(
25-09-2005, 12:25 PM
kayot1k

interesting.
i was under the impression that type r given it was the b18c7
would produce something like 100kw's at the wheels stock ?
your power is only abit more.