R33 Help!

[53ffi]

hey guys and gals, heres the story,

i recently bought a r33 gts+t4, i dont know hoo did the conversion or anything like that.

now, wen u drive it it runs fine, idles well. however at around 3000rpm the engine simply doesnt rev any further. but wen u take your foot off the gas slightly itll rev up. also wen driving along and put foot flat to floor itll drop back gear (s) and rev to say 4500 and jus not wanna rev any further. the engine sounds terrible like its choking on excees fuel or soemthing. anyways an inital thought was wen converted to turbo the ecu wasnt changed. so we looked at it and it has series 2 writin on it, and the car being series one i scratched my head.

its really frustrating me wen a commo comes up next to me and i can barely keep up with it. so could anyone please help me diagnose this problem!!!

thanks in advance for any help.

Tim.

[QWK32]

do you know if the whole wiring harness got swapped aswell? series one 33's run and igniter pack and series 2's don't. what turbo is on it?

[RBWPN.6]

Hey mate i was gettin a similar issue like car didnt wanna rev past 4500 i found that it was gettin no fuel and to much air coz it was runnin 2 high a boost, fixed it with a boost controller and reset my ecu, but maybe u needa tune your ecu 2 run with the new turbo and has it got supporting mods i.e exhaust, cooler injectors posibly fuel pump?

[53ffi]

Hey mate i was gettin a similar issue like car didnt wanna rev past 4500 i found that it was gettin no fuel and to much air coz it was runnin 2 high a boost, fixed it with a boost controller and reset my ecu, but maybe u needa tune your ecu 2 run with the new turbo and has it got supporting mods i.e exhaust, cooler injectors posibly fuel pump?

yea i really dont know wat its got hay. its all stock apart from an exhaust.it appears to be a different acutator on the turbo, and its running stock boost. and sometimes wen driving after a bit of a flog u can smell fuel.????

[aphid]

i might add -

As you take off the car feels dead before about 3000rpm, where it feels as if something snaps and she takes off.. My initial thoughts were perhaps the BOV wasn't hooked up properly, as you here the turbo spooling fine and acceleration through the revs didn't feel consistant with the way the turbo was boosting (no boost gauge in the car so can't check it )

Further investigation revealed that because the car has been converted from N/A, there is no boost tap from the intake manifold for the BOV, and it has been T'd from the carbon canister.. This seemed to me a very logical explanation as the carbon canister could provide inconsistant pressure levels and could be letting the BOV stay even a slight bit open causing a measured boost leak.. When boost got to a certain level, or the space inside the carbon canister finally presurised, in this case at around 3000rpm the BOV would slam closed and air would no longer be escaping, hence the sudden jump in power output..

Timmy has told me now that he has tested this out and there has been no change in how the car drives, so that theory out the window although I would like to try it for myself

It should also be noted that we tried the PowerFC out of my car inside his to check that all the sensors were fine and it wasn't the stock ECU shitting itself and doing the old rich n retard, so it's doesn't look like it's a computer issue either..

Just my 2 cents

[unarmed_skyline]

i dont know why they would tee into the carbon canistor for the bov as the standart nipple on the manifold is there for the bov but its blocked off. i've done a turbo conversion on an na rb25 and i had a similar problem and it ended up being the car was going to rich and retard because the afm's couldnt handle the boost and in turn failed i also had fuel starvation problems with the na ecu and and safc and had to upgrade to aftermarked ecu.

So if i were you i would try swapping for a series 1 turbo ecu and a turbo afm and fix the bov pressure line and see if that fixs your prob. i would also recomend a boost gauge as if it hads a different actuator you may be running higher than standard boost which is a no no with a turboed na. also do you know if fuel pump or injectors have been changed at least to turbo items if not better?? cause they would be next on my list to check,

[53ffi]

thanks to all hoo have had input so far, i will buy a boost gauge tommrow, i also have a rb20det airflow metre here would it worth putting it on to see if anything changes? (im not sure if they are different on the rb20 and 25)

keep the ideas coming guys plz.

Tim.