datsunan Posted May 17, 2004 Share Posted May 17, 2004 Ive recently finished my 240 turbo project and am now trying to build on the power now that the engine has some miles on it. I've been bringing up the boost a litltle at a time and all along it seems to spool slowly and not really put you in the seat as I thought it would. I'm running an 83 turbo engine with the Jim Wolf Tech 350hp upgrade kit, 420cc inj t4/t3, reprogramed ecu, huge intercooler, clean intercooler piping, high flow fuel pump and a ford cobra MAF. With all that I thought I would be really put into the seet when the turbo hits but I'm not. I don't hit 14psi till I'm at almost 6000 rpm. Anyone out there have anything similar that could give me some data on how yours spools, pulls, at what rpm. Suggestions coments? Thanks Paul Quote Link to comment Share on other sites More sharing options...
Guest Cronic Posted May 17, 2004 Share Posted May 17, 2004 Could be the timing, too little cam timing will cause super slow boost. Also if the wastegate spring/actuator is messed up, IE. too long. it will do this. What are you using to control boost? Quote Link to comment Share on other sites More sharing options...
240hoke Posted May 17, 2004 Share Posted May 17, 2004 what boost controller are you using? Quote Link to comment Share on other sites More sharing options...
onephatz Posted May 17, 2004 Share Posted May 17, 2004 if I had to guess I would say that your wastegate is opening to soon or staying open. jesse Quote Link to comment Share on other sites More sharing options...
datsunan Posted May 17, 2004 Author Share Posted May 17, 2004 I'm using a Apexi AVC-R boost controller, right now I'm just using plan and simple no gear based or rpm set points. I have verified my waste gate is closed. The boost has always been slow to reach set point even at lower psi. Does anyone have a t3/t4 that can tell me at what rpm does thiers reach a certain psi? I would think my turbo should reach 10-14 psi sooner and allow me to stay in a power band rather than hitting that 10-14 psi set point at red line. Right? 14 psi at 4000 or 4500 hold it there till red line, or am I being to optomistic. Quote Link to comment Share on other sites More sharing options...
yo2001 Posted May 17, 2004 Share Posted May 17, 2004 My 60-1/stageIII in .63 A/R housing got full boost 12-14psi at 3500rpm on 4th gear pull on the dyno. that was with al. flywheel and 3.90 gear. Quote Link to comment Share on other sites More sharing options...
Afshin Posted May 17, 2004 Share Posted May 17, 2004 I would also say that something is definitely wrong. I hit 15psi at about 4000 rpm with a t3/t4b unit, but even a E trim should fully spool up way before 6000RPM. It still sounds like your wastegate is faulty, open too soon or is leaking (i.e. doesn't seal properly). When at highway speed and in 5th gear and applying full throttle you should be able to easilly built full boost at low RPM, will your car do that ? . Is the car running well otherwise (under boost) ? I assume you already have checked timing Also does it built less boost quickly and then slowly goes to 14 psi or is it also slow to built to 8-10 psi? Quote Link to comment Share on other sites More sharing options...
Guest Cronic Posted May 17, 2004 Share Posted May 17, 2004 Im going to blame the gain on the boost controller. I know with my profec, if my gain is set to "soft" it takes longer for boost to come on. Quote Link to comment Share on other sites More sharing options...
datsunan Posted May 17, 2004 Author Share Posted May 17, 2004 Thanks for the info guys I was really hoping to hear that it should build quicker cause its not fast enough for the money I've spent. Cronic when you say gain is set to soft is that the same as what apexi calls the duty cycle? If my duty cycle is set to low I wont even hit my setpoint. The instructions say to start the duty at 30% and go up till you are able to hit setpoint, I have my duty at 80% but like I said it hits spt at 6000rpm. It may be that I just need to dial in the controller, the damn thing has more settings than my stereo. To answer Afshin no it won't hit 14psi on the highway much below 6000rpm and I to think it may be caused by the waste gate not closing all the way. I had my turbo jet coated but I cleaned off the flapper and the seat befor putting it back together. I did'nt want to take my turbo apart cause I made sure the waste gate was working befor installing it but I must admit now that I know it should spool-up faster, it must be the waste gate. Looks like I need to get out my wrenches. Quote Link to comment Share on other sites More sharing options...
Afshin Posted May 17, 2004 Share Posted May 17, 2004 I would try a few things before taking the turbo out.... 1) disconect the vacuum line to the wastgate actuator and see if you can built boost quickly. Obviously you need to check the boost gauge so you don't get to 25psi and blow the engine. If the boost controler is OK, then you should still built boost slowly. IF boost builds up fast, you know where the problem is. 2) Next disconect the wastegate actuator rod from the turbo and check when putting it back on that there is tension to get it on and that the flap moves freely.... Specially when using a different turbo case such as the T3/T4, sometimes the wastgate actuator rod may be too "long" (based on where it's mounted) meaning that the flap is never fully closed and hence always leaking... Keep us posted. Quote Link to comment Share on other sites More sharing options...
nixcars Posted May 18, 2004 Share Posted May 18, 2004 Paul, after checking the above, you might have to check the rear impeller blades if it's not a new turbo. This means you have to pull the exhaust housing off & do some measuring. Good luck. Quote Link to comment Share on other sites More sharing options...
datsunan Posted May 18, 2004 Author Share Posted May 18, 2004 OH MY GOD!!!!!! I'VE DIED AND GONE TO HEAVEN! I took the down pipe off and felt the waste gate flap while still in place, it was loose enough that I could spin it around but not loose enough that I could fit my finger nail under it. I bent the waste gate mount so it would pull on the gate hard and put it back together. It pulls like crazy now I'm so stoked, I won't sleep tonight, must work on car more, still some minor issues of my intercooler pipes popping off at the worst time I.E. any time! I have an appointment at the dino on friday now I'm looking foword to that. My car finally feels like I had hoped Thanks for the help guys. Dino results and quater times to follow........ Quote Link to comment Share on other sites More sharing options...
lilj Posted May 18, 2004 Share Posted May 18, 2004 grats, hope it all works out for you =D glad you got the problem solved hehe Quote Link to comment Share on other sites More sharing options...
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