Rx7aholic

iTrader: (22)

Hey fellas, I went to Dave at Speed one to get tune twice within a 1.5 year, first let me list the engine stuff, stock ports, Rebuilt by me using Goopy seals and Mazda compression tester shows 9.2,9.3, 9.3 on all 3 faces on both housing at 251 rpm (engine hot). Turbosouce mani and downpipe, fuel: aeromotive pump, Injectors: oem 550, ID 2,000 with Radium fuel damper (injector % at wot 72%) exhaust, Rx7 store resonated mid-pipe, RB dual tip CB. Ignition, oem coils and hks twin power, Denso racing plugs heat range I believe are 10.5 all-round. Turbo system BW efr 8374 with turbosmart twin port actuator, Ecu pfc and Greddy profec b EBC. The dyno run first it was running too rich, so fuel cells got reduce, did a few pulls, still run a little rich, removed more fuel. I should pointed out that we got no ignition breaks, no shortage of fuel . The highest power put down was 391 at almost 19 psi, then we notice that the boost level was dropping off to 15 psi, we thought it could be the EBC solenoid, I removed it and re-plumb to a BW solenoid and use the controller to increase boost, it was flat for few runs and then it drop back to 15 psi (gate spring default) no boost controller on, the kicker if Dave increase boost setting with either the Greddy unit or controller it counteractive, it decrease back to 15, was trying to increase it by 5% increment to get it back to 19 up to 22 psi but it never work, we did let the car cool down Iat's shows 35 to 40 , I am kind of stumble on what can cause it, I know a lot other cars guys preferred to use a 4 port Mac solenoid when using a twin port actuator but I am not sure if that's problem, I know that RB CB can withhold horsepower but the car still should be able to see more than 391 Rwhp. Any input is much appreciated.
Tnx,
Khris

Turblown

iTrader: (12)

Which intercooler ? Can you post the dyno chart ?
I would do a boost leak check, and you could try a pull with midpipe detached for fun. Dave has tuned quite a few of these too without issue..

Rx7aholic

iTrader: (22)

I have the crook willow intercooler, also on the twin port the bottom have 2 ports, does one get cap or it's vented? Currently I have one going to the solenoid and other one cap.

arghx

iTrader: (3)

That's an internally gated turbo? Please give each more specs on the wastegate. What's the spring pressure, if it's internal gate have you adjusted preload, how is the boost control solenoid hooked up

Also, what is the turbine housing size on your turbo

Rx7aholic

iTrader: (22)

The spring pressure is 14 psi, turbo size is T4-.092 IWG, I did set the preload turns to 5, taking from I believe from Turbosource website info. For EBC connection this how I have it: Connect the Top port of the wastegate and port 1 of the solenoid to a pressure only source (by teeing into source) • Port 2 of the solenoid to the bottom port of the wastegate • Port 3 of solenoid vent to atmosphere. I have attach an image of the current setup.

arghx

iTrader: (3)

I would increase the preload next. For safety make sure you have over boost protection in your ECU.