I build an engine last year

B18c5
P30 oversize pistons
Skunk2 pro2 cams
STR cam gears

I take all clearance, Valve to valve and valve to pistons

I tune it on the dyno

it make a smooth powerfull curve with 194 whp

this year, 1-2000 km after the last dyno tunes(last year)

the owner change the intake manifold and Throttle body for skunk2 pro serie intake and 68 TB

he add a ebay tri-y header and a tanabe hypermedallion exhaust.

we lost so much power, that's incredible

look the dyno sheet when I compare last year and this year



one of the vtec lobes on the intake seem to have premature wearing...
the valve ajustement was perfect last year (0.007" In, 0.008") and still the same this year with this problem occured

thanks for your help, and tips to find the problem

 

what header did he have on last year?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Teamdiesel &raquo;</TD></TR><TR><TD CLASS="quote">what header did he have on last year?</TD></TR></TABLE>

comptech 4-2-1 for ITR

 

Did you compression test and leak down check?


Modified by mar778c at 11:00 AM 5/27/2008

 

Correct me if i'm wrong, but isn't a triy header replica better then a comptech?? LOL you lost all that power putting a better header on and a better manifold and tb.

Somethings wrong.. leakdown / CR test time.

I'd put everything back on as you had it and redyno see if it makes the same numbers.
Also was this new setup tuned? if not.. theres your problemo

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IntegraType-R &raquo;</TD></TR><TR><TD CLASS="quote">
Also was this new setup tuned? if not.. theres your problemo</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IntegraType-R &raquo;</TD></TR><TR><TD CLASS="quote">
Somethings wrong.. leakdown / CR test time.

I'd put everything back on as you had it and redyno see if it makes the same numbers.
Also was this new setup tuned? if not.. theres your problemo</TD></TR></TABLE>

I will do leakdown/compression test saturday

for the tuning, I was suppose to do it, but when I see the power curves (wideband AFR was still fine) I begins to investigate the problem

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Garrett &raquo;</TD></TR><TR><TD CLASS="quote">
one of the vtec lobes on the intake seem to have premature wearing...
the valve ajustement was perfect last year (0.007" In, 0.008") and still the same this year with this problem occured
</TD></TR></TABLE>


Did everyone miss this?

If the VTEC lobes are worn prematurely that would cause a large drop in power during VTEC like you're experiencing. What oil was he running? There have been numerous posts on here about running oil with Zinc to help reduce these occurences with cams and rocker arms on Hondas.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00Red_SiR &raquo;</TD></TR><TR><TD CLASS="quote">


Did everyone miss this?

If the VTEC lobes are worn prematurely that would cause a large drop in power during VTEC like you're experiencing. What oil was he running? There have been numerous posts on here about running oil with Zinc to help reduce these occurences with cams and rocker arms on Hondas. </TD></TR></TABLE>

but the wear is only on 1 cylinder, I don't know how much power I could lose

le oil Is full synthetic Motul 5w30

 

Are the rocker arms damaged? it's possible that some arms and maybe only one cam lobe is damaged which would cause a power loss.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00Red_SiR &raquo;</TD></TR><TR><TD CLASS="quote">Are the rocker arms damaged? it's possible that some arms and maybe only one cam lobe is damaged which would cause a power loss.</TD></TR></TABLE>

rocker arm is clean

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Garrett &raquo;</TD></TR><TR><TD CLASS="quote">one of the vtec lobes on the intake seem to have premature wearing...
</TD></TR></TABLE>

you answered your own question right there

same thing happen to my ctr cams. the vtec lobe were geting a nice big flat spot on them. i bought new ctr cams and then have been fine last time i looked at them. new cams been on for 1 year
but for when ever reason i have been seeing premature vtec cam lobe were a lot now a days

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by riceball777 &raquo;</TD></TR><TR><TD CLASS="quote">

you answered your own question right there

same thing happen to my ctr cams. the vtec lobe were geting a nice big flat spot on them. i bought new ctr cams and then have been fine last time i looked at them. new cams been on for 1 year
but for when ever reason i have been seeing premature vtec cam lobe were a lot now a days </TD></TR></TABLE>

good I will buy a new cam and try it

 

Does someone here, know something about the ZincLess Oil?

this is the second time since last year, that an engine using oil without zinc ad cam wear

 

https://honda-tech.com/zerothread?id=2008331

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00Red_SiR &raquo;</TD></TR><TR><TD CLASS="quote">https://honda-tech.com/zerothread?id=2008331</TD></TR></TABLE>

you're awesome

 

the rocker as more wear than the cams





problem solve the power is not back