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Discussion Starter #1
I spoke with the techs @ stillen on how to get more hp from what I have done. They told me to purchase the high boost pulley. They told me that the extra injector they installed with the sc kit has more than enogh gas supply and that they designed this unit to run rich. I can agree because my chrome tips are always black after one run. hp increase from384 to 410 thats a big deal! The vq block is rated for up to 500hp. If i blow up this engine I will build a big bore block. The only draw back for stage III is that it is street illegal ( whos lookin) and it voids stillens warranty on the engine and drivetrain. THey will honor the warranty on the sc unit still.
I have gone this far why stop now! I feel very confident in stillens sc units it runs great and great on gas. Like the tech told me its not the turbos and the superchargers that kill engines but the people who drive and maintain them! I happen to agree.
I hope the power increase is felt , they swear by the differance between stgII and III will keep you posted.( who ever is interested that is)
Ps What up JhonnyBlaze!!!!
 

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Discussion Starter #3
wheel spin

I am AWD and from the start into a turn all 4 will light up! from a straght line on dry pvmt it grabs too well to slip, keep in mind VDC off. MY VDC goes on often when getting on the gas.
 

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It it wise to even run with the VDC on at all? I've read (been a while back) on the My350Z FI forum that you need to pretty much permanently disable your VDC or always turn it off b/c if it kicks in and cuts fuel, the blower doesn't know it and continues to force air, resulting in a deadly lean situation. Has Stillen somehow worked around this?

Also, do you have any issues with the trans shifting at WOT? Does the Stillen unit cut boost during shifts?
 

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Discussion Starter #5
boost cutoff

The boost does not cut off during shifts this is why i cant wait to do a converter upgrade and valve body as well. I feel pretty confident with this unit and have given it a run for the money so far! shifts do not have that much slag but can be improved!
 

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Sounds like you will blow your trans first......

Better do the trans upgrade at the same time.
 

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Yeah, so what about the VDC thing?
 

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Yoooooooooooo

A rob I just got your message. Man, MaryJ. sure know how to convince people how to do some crazy things :lol: :lol:
I agree with the tranny being upgraded at the same time. We got to hook up this week so I can feel how the ST. II feels. I think you will definitely blow the Cayanne Turbo out of the water then if you are handling the Cayanne the way you are now.
I need some overtime for my S/C. I can't wait. I wonder if stillen does finance.? :lol:
 

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sounds promosing.....


the VQ is rated to approximately 450 rwhp...... (who toldya 500, btw??)

keep in mind, this is an absolute value, and the longevity of the motor is very questionable (especially with the stress of awd)

as for the vdc, i was under the impression that it retarded timing, so there's really no worry there, MFGR... (correct me if im wrong!)


i am curious, this 'extra' injector..... it feeds the all cylinders??? (wow)

how much extra timing are you gonna pull uptop to make sure to keep the a/f ratio in correct safe proportion??? simply relying on one injector cant be the answer, right??? (im not up on stillen, so thas why i ask)...

i am up on s/c's and the vq though, and have spoken directly to one of the engineers at infiniti regarding the stresses of the vq (and drivetrain)... at 400rwhp, you are asking the absolute limits of the design of the tranny... keep that in mind too..

im anxious to see new dynographs (and make sure to watch the timing!!... report with a/f charts too... 11.25 is where i was when i hit 400.5rwhp with my vq, at 9lbs of boost)

ese
 

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Discussion Starter #10
9 lbs of boost is alot . I think that with the new pulley only takes the boost up 1 lb from 6.

this VDC issue is news to me and from what I am reading on this site some say it makes a diff others say it doesnt.

I deffinently agree about blowing up my tranny! wish they had a manual setup! I did install a tranny cooler from b&m which helps.

I was told the VQ was rated @ the most 500hp by some guys @ the track in englishtown NJ who race 350zs , so I cant back up this info with facts. IF 450 is in the red than i should be blowing up something soon! :shock:

This extra injector comes from the fuel pump i believe? I am going to call Stillen and speak with the tech marshall who seems to be up on the sc unit. I must admit I do not do much research on these issues because I am to darn busy workin to pay for the toys.
Im sure you know what Im talkinbout!

I have a bunch of pics i want to post and am havin alot of trouble .Got to get the wife to help because I am not to familiar with computers only body systems :eek:

Right now I am in the mist of a new project with my atv yamaha banshee. I am porting, polishing, boring and placing a larger crank in it. I m sure i dropped more benjamins into this toy than my fx. it will also leave my fx in the dust. dont know if any of you ride , but its awsome!

BTW what are you runnin 9lbs of boost in . is it a stillen sc roots or cf unit?
 

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I'll hunt around in My350Z tonight if I get a chance (can't access it from work) and see what I can dig up on the VDC thing.

What happens when you hit the rev limiter (timing pulled or fuel cut)?
 

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MGFR-
Our car is throttle-by-wire, so the VDC is able to close the thottle despite pedal position. My BMW was conventional TB, but it had a SECOND throttle just for traction control. You can imagine that didn't do much for air flow, so many people removed it (IN WHICH case VDC disabled itself so no risk of running lean). VDC can also turn off the spark.

If VDC only cut the fuel, wouldn't that cause the car to run lean even NA?
 

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dinofx35 said:
MGFR-
Our car is throttle-by-wire, so the VDC is able to close the thottle despite pedal position. My BMW was conventional TB, but it had a SECOND throttle just for traction control. You can imagine that didn't do much for air flow, so many people removed it (IN WHICH case VDC disabled itself so no risk of running lean). VDC can also turn off the spark.

If VDC only cut the fuel, wouldn't that cause the car to run lean even NA?
Not sure; that's why I need to research it. I just remember reading about it a while back, but this was when people were first starting to do FI on the Z, when things were a bit more unknown, so it may or may not be a real concern.
 

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I had a 260Z with an aftermarket turbo kit on it and used to run some pretty extreme boost at times. I added a pressure sensor in the intake manifold that was set to 10PSI. At boost pressures over 10PSI it would inject methanol into the intake prior to the turbo. This served a couple purposes. First is I could run the high boost without any detonation. This worked much better than water injection as the methanol burns and adds to the HP, which water does not. Second was the methanol cooled the intake air charge to a much greater degree than the water did. Kind of like an intercooler. While this resulted in cooler combustion chamber temps, the combustion chamber pressures where higher.

Of course the drawback is first finding methanol. Then you have to plumb everything with Stainless Steel lines to prevent corrosion.

If you are interested I can provide you with additional information on how it was setup.
 

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silverback said:
I had a 260Z with an aftermarket turbo kit on it and used to run some pretty extreme boost at times. I added a pressure sensor in the intake manifold that was set to 10PSI. At boost pressures over 10PSI it would inject methanol into the intake prior to the turbo. This served a couple purposes. First is I could run the high boost without any detonation. This worked much better than water injection as the methanol burns and adds to the HP, which water does not. Second was the methanol cooled the intake air charge to a much greater degree than the water did. Kind of like an intercooler. While this resulted in cooler combustion chamber temps, the combustion chamber pressures where higher.
What is considered extreme? My brother runs 27 PSI on the strip and he and many others use half methanol and half water.
 

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The most I ran was 38 pounds of boost. You could adjust the boost from inside the car, so normally it ran in the 22 to 25 range. When I really wanted to blow someone away I would crank it up.

Now I need to mention that this turbo was not just added to a stock engine when it was running those boost pressures. It was rebuilt at a friends shop that specialized in performance rebuilds. The compression ratio was dropped to 7 to 1. It was balanced, and blueprinted, the head was ported, and a special grind cam was installed. The block was o-ringed to help retain head gaskets.

Before the motor was rebuilt I was running about 20 pounds of boost and a couple times it actually blew the head gasket out the side of the engine at cylinder # 5. I also ended up having to pull the head off and o-ring the intake/exhaust surface intake ports. At the high boost pressures it was blowing the intake/exhaust gasket out.
 

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Discussion Starter #18
VDC

I ran with the VDC button off after holding for 10 secs. Did not make a bit of diff. Slip light kept coming on when tires were letting loose. I guess it will save my drive train and tire wear because spinin can be addicting. Put on high boost pulley last night, feels much better. Just havent had a working intercooler pump for 1 week . They (stillen) finally got a new manufacturer for the pump after they sent me 2 and both failed! this pump is twice the size and hopefully will do the job.

loosing alot of hp but no harm to the unit. Its like runnin a stg 1 .
PS you guys seem to know your shtuff on these topics hats off toya!
 

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If you really want to dig into all this more, I highly suggest you register at My350Z.com and browse the FI section of the engine mods forum there. Tons of info. al all FI units, add-ons, tranny mods, etc. Look up "12secZ" and shoot him a PM; he's putting down 400 RWHP through an auto trans and bracket races it regularly. Don't know that he's done anything to the tranny asside from a higher stall converter. He says the stock tranny can handle up to 600 HP.
 

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2 quick comments:
-transmissions are rated by torque capacity not HP
-There is a 350Z running 10's,so whatever that T/hp level is,the block is capable,it is a worked motor as it should be at those levels(this is 500+hp NA)
 
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