need helppppppppppp power lost on transition

Alchemis

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yo guys,

need some help here....

my machine... before PFC...

i dynoed and reading is 260 on the cranks...
but on the wheel... power lose until left approximately 200.

anyway, my engines are 265 according to ah choy...
just wonder what can cause such big lose...

how should 265 engines behave on dyno when it's stock on the wheels?

oh yeah.. mine has the setup as below

DP, MP, Apexi Power Flow, Blitz BOV, Blitz BUR SPEC
the rest are stock.,
 
phat7 said:
what ecu?

previously was original 265 ECU. now i just fitted PFC. still tuning @ links.

does ECU has anything to do with the power lose between the crank and the wheel ?
 
Need more info

Alchemis,

I'm interested to find out how you know the power reading at the crankshaft (flywheel) when it is measured at the wheels??

Anyhow you need to be a little (ok a lot) more detailed in your description of your problem for forumers to have a stab at identifying the same.

Firstly do you have a boost meter? If yes do you see boost on the first turbo and then little or none on the second turbo when it should kick in at around 4,500rpm?

Who maintains the engine - yourself or ah choi? Was it rebuilt recently and what is the compression reading for each rotor?

best regards,
13btt
 
i don't have a boost meter but currently the car is at links@sunway (my usual maintainance place, maintained by Kee and also John) smaller maintenance i do it myself...

still under tuning ....fitted with PFC.

the boost... i've seen temporary hooking up a boost meter and running around 0.5 bad normally, 0.6 bar (when it spikes). around that range.

the attached are the dyno results.. one of them are with correction.. which is very low in Bhp..

the boost still comes on at 4.5K RPM as u can see the switch on the line.

it's a 265 engine. haven't gone through any rebuild before. changed flywheel couple of months ago as it has a chip on it.

i visited ah choy for compression test. he says my engine did not vibrate at all... it's as calm as a lake water... don't need to do any compression test.

is the information enough ?
 
i would like to know more bout your pfc maps? can you post them up? is there any sort of error coming up on the dash? i think your settings are off somehow. could be knock threshold.
 
when i see the problem of power lost between the flywheel and the rear wheels, that time i was still running stock ECU with only S-AFC2.

now if it's with PFC, i still unsure how's the performance. but i can conclude that the power lost shouldn't be related to the ECU or power of the engine ( maybe the engine power is not very good but i would say it's mechanical lost)

PFC Maps...i don't have it yet... it's still at links...able to get it on saturday only.

besides that, my package doesn't include a FC commander...which is quite expensive for a 2nd hand PFC plus full tuning. i pay around 4 K for it.... is it expensive or reasonable ?

anyway....how do i get the maps ?

those 265 engines that the number means 265bhp on the rearwheels or 265 on the flywheel ?
 
Power FC installation failed. 2nd handed Power FC is meant for single turbo. unable to fit in and the system is acting wierd. oil pressure shotting to MAX everytime they start the engine. when they start to tune it, knock occurred. then they stop it. and cancelled it.

they tightened my bolts and vacuum hoses so that my boost is constant now... only 0.5 bar

and i changed my rear axel and gear box lube. now the car runs so smooth, although running stock ECU..

but this is what i can see now

270 bhp on the flywheel
average 10 on A/F (quite rich)
190bhp on the wheel before change of axel and gear lube
should be 220 on the wheel after change...(significant increase of smoothness after change)

i should fix the boost first.. push it back up to 0.7 bar.. if it's the hose leak... patching it should make my boost wayyyyy up to 1.x bar... as i have a free flow exhaust and intake.
need to take care of it... to 0.7 bar using some manual boost control.

then put in power FC if available or FconV to tune the fuel to meet the higher boost. targetting around 0.8 to 0.9 bar.
 
i have the datalogit for pfc. i do not mind us plugging it in to check important settings and from 1 look we'll be able to tell if the setting's are shit.
 
at the moment, i don't have the PFC. Kee @ links says he won't charge a single dollar if the PFC doesn't fit.

let me get the boost done at AH Choi's first. then i'll source for PFC. going back to Kee's to tune.

actually Kee suggested to put in a Haltech E6x that includes a boost controller that cost.. 7 K..... sooo expensive...

get my boost done first. then only go for PFC. theoritically, my engine should produce boost at about 1 bar due to the restrictless exhaust and air intake.

stay tune...
 
boost patched.. but not sure how far it's going.. but ah choy mentioned it's probably over boost...
during the 2nd turbine kick in.. it's wonderful... buttttt
during 5000 to 8000, it feels a little jerky.. has around 4 to 5 jerks...
which he says it's boost cut...
from 0.5 till boost cut.. imagine how big is the leak...

the fix patched the y pipe coupling.. totally loosen up...
and also underneth the vacuum tank there's a one way check valve.. that one broken as well.

and.. the interesting part is that the car has the waste gate control and pre-charge control electrical socket disconnected. and there are couple of vacuum hose are capped.. not sure for what reason...

due to CNY, no one able to fix this... the advise that i have.... don't boost.... and will bring it back for checking... check what's the reaon of capping and disconnecting...

other than that... maybe next thing is a boost controller... push it down to 0.8 bar... or 0.7... if things are fine.. and the dyno readings are not too lean.... that's it.. if it's too lean... will get myself an emanage.. (unless found some cheap PFC or Fcon S)
 
did you receive the reply to your pm?

pls get yourself a proper fuel controller. read up the non successful attempts by re owners with emanage.

get a fuel regulator to bump up fuel and fuel pump if you dont have one yet.
 
ok got it...
will patch the boost problem first at the moment. probably a boost controller or manual boost controller (found at robinette.com).

then slowly source for a reasonable priced PFC or Fcon S.

there's another more crucial problem i found. coolant leak... probably cracked radiator. but i found the pressure of the cooling system is very high.. why is that happening ?
 
if you have a cracked radiator the pressure would be lower. unless you have the dreaded o"ring issue. do the champagne test!

where do you suspect the crack is on the radiator? whats the pressure psi? the radiator end tanks tend to have hairline crack which is visible after warm up. if you need a stock radiator let me know. i just rebuilt a stock unit and had the radiator slr coated.
 
hey masters,

most of the stuff i mentioned is fixed, boost leak, leaking coolant (replaced radiator). my boost is standing at 0.7 bar and no hesitation.

today the AST failed on me. the buzzer went on ... and yeah... got someone send me replacement AST to get my ride moving. the problem i see just about an hour before the failure... gears are difficult to shift.... i'm in a hell mass jam.

the RPM of the engine shots up to 3K rpm. Its not hard start... it holds at 3K rpm even the engine is hot...and the exzhuast is like constant farting.. blup blup blup blup... not the usual back fire bang bang....

worrying my apex seal is dead due to over heat...

anyone know what' that ?
 
Firstly, i dont see how you're coming up with those "crank" HPs. What are you using to determine ur engine HP?

Secondly, PFC is fully programmable. I do not believe there is such a thing as a PFC "meant" for single turbines, vice versa. It's a fully versatile ECU. Maps can be downloaded off www.rx7club.com, and you can work from there.

I think with the mods you've listed there, i highly suggest you get yourself a "good" boost controller. The PFC can be used to manage boost, but it's well known that it's not any good at that, its gonna be too busy doing other things. BTW, free flow exhaust + aftermarket intakes will not push your boost past 1.x bar. And seeing that you have no boost meter, how are you measuring boost pressure at the moment?
 
ok... latest update... my car got fixed...at ah choy's...
previously boost is at 0.5 when i was running on dyno.
crank HP... based on computer calculation. it's like a correction factor based on the signals
spent almost 2K on my last visit.. changing some broken intake gasket, replace all the vacuum hose... replaced a punctured radiator..
end up now running perfectly 0.7 BAR...i got a boost meter already...

boost controller.. will be probably after i put in an after market ECU..
 
everything done.... running perfectly, full of power with FAMspeed ECU.
track ready.

lacking a set of Hi-Low Soft-Hard adjustable absorbers.
lacking a set of road hugging rubbers.
 

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