PROBLEM: I was losing psi on my GReddy turbo. We assessed the problem as a loss of base boost pressure (psi without boost controller turned on). Base boost had dropped to 3 psi

I then tightened the actuator rod nut on the actuator lever and it increased my base boost from 3 to 5psi. I turned the nut in about 1/8 of an inch.

I'm wondering if I can turn it in further or at what point turning it in (tightening) the actuator rod could cause problems/damage to the turbo.

I want to get my base boost up to 6 or 7 psi, is it safe to do this with the Actuator rod adjusting nut? This of course is important since the GReddy boost controller (ProfecB) can only increase boost to 110% of base boost pressure. If base boost sucks then top end with boost controller on will suck.

I may need to get a new (universal) actuator from GReddy, but at $150.00 I'm trying to avoid that.

Please let me know what you think.

David


[Modified by greyzone, 1:33 AM 11/1/2001]


[Modified by greyzone, 9:12 AM 11/2/2001]

 

Hey Greyzone, did you get your car dyno'd to figure the 210whp? I've got a GReddy on a 6G EX also with an AVC-R. If you don't mind, what's your setup? You can make it an IM if you'd like, thanks

 

The 210 was at 12psi, normally i run it at 11psi on high boost and 7-8psi daily driver.

–96 EX Coupe 5spd
–1.6L SOHC VTEC D16Y8
–GReddy Turbo w/Blue Box
–GReddy Type S BOV
–GReddy T-31 Intercooler
–GReddy EVO Exhaust
–GReddy Boost Controller, Profec-B
–Gutted Oversize CAT
–NOS Fuel Pressure Regualtor
–Missing Link
–AutoMeter Phantom Boost Gauge
–AutoMeter Phantom Fuel Pres. Gauge
–A’PEXi V-AFC
–HKS Turbo Timer
–Holly 255lph in-tank Fuel Pump
–MSD SCI Ignition
–MSD Blaster 3 Coil
–MSD Pro Cap
–MSD Plug Wires
–NuForms Block Guard
–2 Mil Head Gasket (GReddy, of course)
–ARP Head Studs
–NGK BCPR7ES-11 gap @ .32


[Modified by greyzone, 9:27 AM 11/4/2001]

 

I don't see why adjusting the rod would cause any problems. We had to do the same thing you did on my bro's car to go from 3psi to 6psi, and haven't had any problems.

I'm very interested in your setup as well. I'm running with the blue box as well- it still worked at 12 psi? I've been told its only good to 8-9 psi. I'm running almost the same exact stuff you listed, minus the T-31 intercooler, V-AFC, ignition, blockguard, and 2 Mil headgasket. How do you have it tuned?

What is your ignition timing set at? I'm having pinging at 7-8 psi even though my fuel is fine and 2 degrees retarded timing. I'm guessing the thick headgasket is the answer. How exactly did the gasket affect your car? Is it really weak out of boost? Did it stop any detonation?

 

I'm running 4 degrees retarded. THicker head gasket lowers compression so really the benefit is IF it does detonate the compression is not so high. THe higer the compression in the cylinder the more potential for damage with detonation.

The car runs great at 7 or 8 psi and is still quite fast. its also about 170whp at 7-8psi so its still pretty quick.

My understanding of the blue box is it mostly tricks the ECU into thinking the engine is running cold all the time so it delivers more fuel to the engine. I dont know if this is by simply increasing the duty cycle of the injectors of if there is some type of increase in fuel pressure. I have not had a problem running lean and I can quite easily get it too rich by increasing the NOS FPR or adjusting the injector duty cycle with the VAFC.

I love the VAFC, it has really allowed me fine tunning in specific rpm ranges when I have needed to pinpoint specific problems of running too rich, but maybe only at 3000 to 4000 rpms.

The car is not weak out of boost and still runs very strong. Compression dropped from 175 down to about 140.

Notice what you are missing: "minus the T-31 intercooler, V-AFC, ignition, blockguard, and 2 Mil headgasket." Without that stuff I would/could/should not really boost over 7psi and would probably be around 150-160whp at best. Those additions have made a huge difference.

I never have had (knock on wood) any pinging problems since I installed this turbo bout 30,000 miles ago.

I am getting it dynotuned next Wednesday so I am looking forward to that. Hoping to work out some minor problems im running into, but for the most part Ive been extremly happy with the set up.


[Modified by greyzone, 9:11 AM 11/2/2001]

 

Well, my setup remains untuned as well. I'm running .50 bar (7.2-7.3psi) with a BBK 255lph pump, stock injectors and a 10:1 FMU, car reads stoich during full throttle boost, no pinging and my plugs read fine. I'm installing my RC 440's this weekend and ditching the FMU so I'll have even more insurance, but even now I'm having a pretty good time. I'm running the stock tiny GReddy DP, stock cat and stock exahust so my whp is defintaltey limited to like 150ish whp at 7psi, but i'm hoping my 2.5" DP, 2.5" TP and 3" catback will help remedy that and I can start sqeezing 8-9psi with the 440's on there for some 170-180+ whp runs Gotta get this thing tuned!

 

one thing to check, I think 310s would work better than 440s.

And also, you're running stock exhaust? That can really be dangerous for your turbo, causing back pressure and overheating of the turbines cause the system aint gonna breathe very good. Better fix that one ASAP...

I woulndt run 6 or 7 psi with a stock exhaust.


[Modified by greyzone, 1:43 AM 11/3/2001]

 

The blue box reads map sensor voltage to sense boost level and controls injector pulsewidth/duty cycle accordingly. Greddy told me its only good to 8-9 psi, but if its working for you at 12 psi and 210 whp, thats great!!

I've been using an adjustable fpr to somewhat tune the air/fuel ratio. What are you running for fuel pressure? 40 psi fuel pressure gives me about a 12.5:1 a/f ratio, which is perfect. But I need more adjustability like your VAFC or something- it runs too rich at 3000-4300 rpm. Then it starts to lean out and right at the vtec changeover, 4900- 5200 rpm, its a little too lean and sometimes I get pinging as it passes through that point. But from 5500 rpm on up its perfect at 12.5:1 a/f ratio.

At 5.5 psi, 2 degrees retarded timing, my car made 152.8 hp @ 6600 rpm and 135.7 tq @ 5250 rpm.

At 7 psi, 5 degrees retarded timing, it made 165.1 hp @ 6750 rpm and 144 tq @ 5000 rpm. Do my numbers seem about right??

Isn't it true that the D16y8 has a slightly higher compression ratio than the D16z6?? Like 9.6:1 compared to 9.2:1?? I ask because you said your compression was 175 psi before the headgasket. Both me and my bro's stock D16z6's read 190-195 psi across the board. Weird, huh?

Also, at 4 degrees of retard, my car feels pretty sluggish down low. Add a big drop in compression to that, and I can only imagine how weak it would feel out of boost. I must be over sensitive about that or something, although on the dyno running 5 degrees retarded I lost 5 hp and 8 tq from 2000-3250 rpm, when the boost finally started building. My car was dynoed in 4th gear, so boost built up really slowly- on the street it usually starts building at 2000 rpm and reaches full boost at 3000 rpm. Do you dyno in 4th??

 

Their is no positive boost level at the MAP sensor on my setup due to missing link bleeding off boost. If the MAP sensor reads anything over zero its going to code.

I dyno in third under full load...i dont see the reason or benefit to doing it in fourth...seems like it would just take longer to build up to appropriate load. THird is adequate to do that.

Ive been running FP at 38 to 40 idle and close to 58 under full boost, pretty much slightly rich all the way up. Ive been too rich at 3000 -3500 rpm but the VAFC took care of that easily.

Your numbers sound about right.

The y8 has some refinments over the z6, primarily in head design/performance. I dont kno the differences in compression though. I think stock compression in mine should be 180 with a difference no greater than 20 per.

A loss of 5hp and 8 tq doesnt seem like a big deal, at least to make it noticably sluggish. I wonder if something else could be going on. One thing that does irritate me tho is the getting going stuff, like starting off from a total stop. Sometimes its sluggish there, but once its going, anything over 2000 rpms its running great with no noticable sluggishness.

Im getting dynoed this Wednesday, but Im having problems with my boost...cant get over 9psi. Its really got me miffed as to what is going on. Im beggining to think the boost controller (GReddy ProfecB) is on the fritz. Im gonna check the filter on it tomorrow...at 9psi im probably around 185whp but i like 200, thats always been my target goal.



[Modified by greyzone, 9:36 AM 11/4/2001]