Well, I went to the dyno yesterday hoping for the magic number of 300whp and came home very disappointed/frustrated. No matter what the boost was set to(9-15lbs), I would pull anywhere from 165-170whp. Fuel and timing curves were right on, compression test was 200 across the board. I am running a t3/to4e 50 trim .48 ar on a d16y7 and the turbo would spool and hit full boost at around 4200 rpm and hold steady til we let off but power would start to fall off after 5500rpm which it shouldn't do with a turbo of that size. We tried a run open DP to see if my cat was clogged up or something and that didn't do ****. My new motor had 700 miles on it once it got to the dyno and I was starting to think that the rings never got seated properly and were allowing blow by. Would the compression test yield lower #'s if my rings weren't seated? I thought it would, but I am going to try a leakdown test later today or tomorrow and see what comes up. Any ideas are greatly appreciated.

EDIT: heres the setup

d16y7
cp pistons/eagle rods
ARP's
ferrea valves/springs/retainers
maxrev manifold/DP
tial 35mm WG
rc550's
walbro 255
t3/to4e 50 trim .48 ar
greddy type 31 FMIC
spec stage 3 6 puck clutch
ACT streetlite flywheel


Modified by Pfieffdog at 10:27 AM 7/13/2004

 

bump

 

if rings were not seated right then you would yeild poor compression results

dont feel bad bro.. i only made 196whp on 8 psi on my motor... yet it is VERY healthy... it makes no sense to me..

 

thats really wierd . somthing else is comming into play here . maybe you just need better flow , what tb and im are you running? and p&p work?

 

that's weird. where's the boost gauge signal coming from? possibly u have a boost leak somewhere after that?

 

ya many factors go into play.. i never realized how sensitive forced induction is to humidity and outside air temp and air density. On a very cool day i feel like im making a ton more power then when it is hot as hell outside. Also it could be a problem with the dyno? settings are not calibrated properly perhaps? I know when i was on the dyno my car was having some serious heat soakage.. The first day i went i was making 227whp !!! then the next day i went back .. it was like 20 degrees hotter out.. i couldnt get over 200whp.

 

hell ya , in the morning when it was real cold i could shift like a granny into second , then slowly go to wot and it would loose all kinds of traction . on the warmer days first would bearly break

 

Boost was being read from the boost gauge as well as the dyno and both were consistent with one another. The dyno is reading right because I went out on the road and did 2 back to back pulls at 10 and then 15lbs and it didn't feel any different(slow). Throttle body is a stock y8 TB and its a y8 IM. Another other suggestions?

 

Also, what would be causing a decent amount of smoke out the breather filter?

 

\\<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Pfieffdog &raquo;</TD></TR><TR><TD CLASS="quote">Also, what would be causing a decent amount of smoke out the breather filter?</TD></TR></TABLE>

this smoke you are referring to is "blow by" smoke.. its essentially a sign that there is not enough crankcase ventialation process of the motor.

 

Same thing with me, ive pretty much guranteed myself that my rings are shot in my pistons, i burn a **** load of oil, and no power past 5500...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by J337_UNIT &raquo;</TD></TR><TR><TD CLASS="quote">\\

this smoke you are referring to is "blow by" smoke.. its essentially a sign that there is not enough crankcase ventialation process of the motor.</TD></TR></TABLE>

And one would go about fixing this how?

 

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

And one would go about fixing this how?</TD></TR></TABLE>

you have to get a catch can....however the access crank case gases not being ventilated is not likely the cause of your lack off power at different boost levels.
I would suggest doing a compression test however you have already done that....so I'm not sure whats the cause.
good luck

 

pistons/rings.. d16y7, 110 bucks. msg fjt.. get thoose 8.5:1 suzuki pistons, some cheapo hasting rings. problem solved and then some.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DewMota &raquo;</TD></TR><TR><TD CLASS="quote">pistons/rings.. d16y7, 110 bucks. msg fjt.. get thoose 8.5:1 suzuki pistons, some cheapo hasting rings. problem solved and then some. </TD></TR></TABLE>

I'm already running cp pistons/eagle rods

 

back up

 

What does your fuel system consist of and what are you using to tune with?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DIRep972 &raquo;</TD></TR><TR><TD CLASS="quote">What does your fuel system consist of and what are you using to tune with?</TD></TR></TABLE>

Fuel system is rc550's, walbro 255lph fuel pump, and tuning was done with hondata s100b

 

here's the only things i could think of based on motors that have done the same thing:

1.turbo is trash
2.motor is trash
3.it's a single cam

 

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

Fuel system is rc550's, walbro 255lph fuel pump, and tuning was done with hondata s100b</TD></TR></TABLE>

ok that looks good. does your engine have vtec? I was gonna ask if it is engaging?

 

Sounds like you have a boost leak. If the leak is small enough, you will still build
boost. THe turbo just has to spin like hell to keep it up = falling out of its efficiency
range. WAAY out of its efficiency range.
At least i can only guess without seeing it in person, but thats the most likely thing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DIRep972 &raquo;</TD></TR><TR><TD CLASS="quote">

ok that looks good. does your engine have vtec? I was gonna ask if it is engaging? </TD></TR></TABLE>

The d16y7 is a non vtec motor so vtec engagement wasn't a concern.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rioninja &raquo;</TD></TR><TR><TD CLASS="quote">Sounds like you have a boost leak. If the leak is small enough, you will still build
boost. THe turbo just has to spin like hell to keep it up = falling out of its efficiency
range. WAAY out of its efficiency range.
At least i can only guess without seeing it in person, but thats the most likely thing.</TD></TR></TABLE>

This wouldn't show any power differences between 9 and 15lbs?

 

i am sure this seems like a weird question but is your crank KNIFE EDGED?
also what manifolds are u using? i.e. intake and turbo? and any head work?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by allablur &raquo;</TD></TR><TR><TD CLASS="quote">i am sure this seems like a weird question but is your crank KNIFE EDGED?
also what manifolds are u using? i.e. intake and turbo? and any head work?</TD></TR></TABLE>

Crank is not knife edged. IM manifold is from a y8 and the turbo manifold is a maxrev log manifold. Head is built with ferrea valves/springs/retainers and I'm using ARP head studs