No power after 5000rpm???

[tayl51601]

I need help trying to figure out what is going on with my car after about 4 or 5000rpm..........
I have a B16A2 that is turbod, i got a new clutch put in last week though when the revs get too high it feels as though something is slipping. Its not the clutch i know that much, but i dont know what else could possibly be slipping.

I got the car tuned by APC a few months ago, i had put in a new fuel pump, injectors, and hondata and got it tuned. When i got it back it was perfectly fine except for the clutch slipping when changing gears at first. The clutch wore out completely very soon after picking it up and i have only just managed to replace it. Ever since i got it back with the new clutch this problem has been happening.

I got no idea what could possibly be not allowing the power to get to the road.........

Could it be somthing to do with the flywheel or gearbox when the clutch was changed?

Any ideas?????

[Mr_will]

how much power are you making and what clutch are you using?

[tayl51601]

how much power are you making and what clutch are you using?

I got 135kw atw........

APC built my stock clutch up so its the same as a cushion button so there shouldnt be any problems with the clutch.
I did a quick gear change yesterday when it was pushing out some power between 4 and 5000rpm and the clutch bit hard, no slip at all so i dont think its the clutch...........

[Gio]

Should have posted this in the forced induction section, might get you more help there.

[tayl51601]

Should have posted this in the forced induction section, might get you more help there.

Yea i though about it, not really anything to do with forced induction though.
Its something thats not working properly since the clutch change.............

Probably something around the gearbox or flywheel.........

[acey]

try checking vacumn lines for boost leak, see if its holding consistent boost above 4-5k
could also be that your clutch is not up to the task, recomend trying exedy hd..

[thepope1986]

slave cylinder bled properly?

[beeza]

DIY: Boost leak tester

http://www.youtube.com/watch?v=atretf9u-Mc

[Limbo]

which turbo?
check for boost leaks or actuator problems.
U sure its not the pressure plate acting up?
i'd take it back to the clutch people to ask them to have a look

[TODA AU]

Just out of curiosity, has the speedo been working latley?

[jaz3]

First step would be to get it pressure tested if I were you. Sounds like a boost leak. Usually happens at high RPM.

[tayl51601]

Just out of curiosity, has the speedo been working latley?

No the speedo stopped soon after the tuning, i wouldnt have know if that was affecting anything before becuse i had a stock clutch which was slipping a heap.............

I kind of think its the clutch i got put on, it is my stock clutch which they built up to a high torque cluch with cushioned button plate............
When i go into high revs i loose 1 psi and it feels as though the clutch is slipping.

[TODA AU]

No the speedo stopped soon after the tuning, i wouldnt have know if that was affecting anything before becuse i had a stock clutch which was slipping a heap.............

I kind of think its the clutch i got put on, it is my stock clutch which they built up to a high torque cluch with cushioned button plate............
When i go into high revs i loose 1 psi and it feels as though the clutch is slipping.

Right-oh… That’s probably the issue then…
No Vtec.

You said previously you have a Hondata.
So you know, the parameters for Vtec to work are engine temp, Throttle position & road speed.
Without the road speed being set to zero, it won’t hit Vtec with the speed sensor inoperative.
I’m guessing you have an S100 as the S200 & S300 have launch control & if this was working, you’d be complaining about a low rev limit.
Anyway, I’ve added a screenshot of the Romeditor 4 software so you can see what I’m talking about.

http://i235.photobucket.com/albums/ee117/TODA_AU/HondataRomeditor4screenshot.jpg
Hope that helps

Cheers

Adrian

[tayl51601]

That makes sense, so if i fix the speedo it should be alright..........

How does it explain the 1psi drop though?

Thanks for the help!!!

[tayl51601]

I replaced the vss over the weekend, worked perfect
I have vtec again lol............ Its dropping 4psi in high revs now so i think i still got a slipping problem........ Im taking the car back in on wednesday to get it sorted.

Thanks for all the help!!!

[TODA AU]

Nice... Good to hear... :thumbsup:

Re boost drop @ high rpm...
Is it a sudden drop or does the boost peal away gradually?
Also what method of boost control are you using?

[tayl51601]

Nice... Good to hear... :thumbsup:

Re boost drop @ high rpm...
Is it a sudden drop or does the boost peal away gradually?
Also what method of boost control are you using?

The boost drops from 8 to 4psi over about 1000rpm range after vtec starts.......... Could it possibly be my exhaust thats too small? Its a 2 1/4 inch with high flow cat.
I havent got a boost controller, its just the avo kit with no bov or anything.........

[TODA AU]

Is the turbo the standard default turbo supplied with the AVO kit?
An electronic boost controller such as Turbo-Smart E-Boost II (excellent product)
Will fix part of the issue.
But if your exhaust is restrictive, this will cause the boost drop.
Has it always occured or you've only noticed it recently.
Also, speak to your tuner, he should be able to can let you know if this was happening before.

[tayl51601]

Yea the turbo is the standard stage 2 kit from AVO..........

I dont know if it has always occured, when i first got it tuned i didnt have a boost guage lol i have only noticed it recently but who knows if its always been like this.
Im going to take the exhaust off tonight and go for a quick drive to see if that is whats restricting it........
Ill also speak to my tuner and see what he sees, ill let you know how it goes tomorrow.
Wish me luck lol i cant wait to be able to get it going 100%

[tayl51601]

Ill also speak to my tuner and see what he sees, ill let you know how it goes

Just spoke to him, reckons its normal for that to happen in vtec...... That boost controller will apparantly fix it so im going to get one of them and get him to tune it again so i can have 8psi constantly..........

[Q_ball]

Moved to FI forum.

[TODA AU]

Just spoke to him, reckons its normal for that to happen in vtec...... That boost controller will apparantly fix it so im going to get one of them and get him to tune it again so i can have 8psi constantly..........

:thumbsup: sounds good...

[tayl51601]

Just in case anyone reads this thread, apparantly loosing psi when vtec gets going is not normal.........

I found out last night it was happening to me because my exhaust was too small lol
Went for a drive with no exhaust and it sat at 8psi perfectly all the way............

[TODA AU]

Yeah, I should have mentioned yesterday that it's probably not such a good idea to do that.
Yes it will give stable consistent boost,
But as your tuner said it was dropping off boost before,
You're pushing the engine to a part of the fuel & ignition maps that haven't been tuned.
So though the risk may not be huge, there is a risk of engine damage or failure.

As a side note, OEM often use restrictive exhaust systems as a fail safe boost control.
A more restrictive exhaust will limit maximum boost potential.
Conversley, in tuning, the more free flowing the exhaust system, the less total advance required of the ignition. So be careful.
Cheers

[lookingforboost]

just have a larger piping fitted say 2.5 inch and use a boost controller even a bleed valve to hold it at the 8psi

i would guess that its running off the wastgate that is plumbed into the cooler piping just using this method will just about always cause a drop in boost pressure in the higher rpm limits.

hence why you fit a bleed valve or electronic boost controller

[kraiye]

Just in case anyone reads this thread, apparantly loosing psi when vtec gets going is not normal.........

I found out last night it was happening to me because my exhaust was too small lol
Went for a drive with no exhaust and it sat at 8psi perfectly all the way............
Well I know half your problem... 3 letters... APC!
lol
seriously, when it comes to Honda, find another tuner

[tayl51601]

Well I know half your problem... 3 letters... APC!
lol
seriously, when it comes to Honda, find another tuner

Yea i know that now lol
I thought they did alright because the graph was really straight, but after talking to a few people they havent done a very good job at all.......
first time i have ever driven a honda turbo let alone turbo car at all so i had no idea lol

I now got my car booked in for april with Adrian at Toda....... Will be much better when i get back!!!

[Limbo]

wow quite a trip, but Adrian is good at wat he does, mine was also tuned by him

[destrukshn]

wow quite a trip, but Adrian is good at wat he does, mine was also tuned by him
my boosted b18c2 is also tuned by him
=)

[tayl51601]

wow quite a trip, but Adrian is good at wat he does, mine was also tuned by him


my boosted b18c2 is also tuned by him
=)

This is exactly why im making the long trip down there lol, theres not many places in brisbane that can do a good tune on a honda..........

And adrian has already helped me out, like in this thread, so im confident that my car will be running properly when i leave his shop lol