whats the most boost you can run with out blowing your motor and how much hp can you expect. We are in the proccess of making a custom kit with twin gt28 turbos which will be availble this spring. My next question is how much Hp can be put to the wheel can u produce with out blowing?

 

400rwhp is about as much as you should be pushing on stock internals.

 

I have 3 friends all tuned by the same shop running over 400whp. And no signs of a problem for thousands of miles.
350z 420ish
G35 430
350z 415
Mine after Jan1st 440(hopefully)

Anything over that is probably not advised but if its done right who knows what it can handle stock.

 

This question is really difficult to answer, since engines have blown anywhere from 330whp to 430whp. There doesnt seem to be a magic number of when the stock internals let go. i have been running mine at 400whp + for 12,000 miles without any problems...but maybe I am just lucky. So many of these motors have been damaged by F/I, that I wouldnt be pushing more than 375whp and a perfect tune without moving to forged internals. Thats my opinion...others will vary.

 

Some data I did hear reportedly from the Quality Engineers at Nissan was that the limit of the stock internals with a CORRECT AFR for the power is 465 crank horse. Granted this is the average and not necessarily the law. With proper tuning I wouldn't venture above 420-430 RWHP without interals. And thats with a REALLY good tune.

 

there both right..so many z's have gone down at different hp settings its hard to tell....the rule ios tunning and money.

 

It sounds like we all agree with the limit. Definitely over 400 or 420 ish is pushing it. The reason I didn't do forged internals, low compression and all that is that my tuner believes we can make 400 to the wheels safely and then a year later rebuild it to make 600 or so. That way I dont get bored with just 1 stage. I can fall in love with it all over again with the upgrades.

 

I think when im all said and done I will settle with 7 psi and a great tune on it to be safe. I spoke to a good friend of mine who is pretty famous in the NHRA/nopi world he told me 5-7 psi no prob 7 being on the high side. So I will go for 7 and a great tune. If he reads this thanx for the Help vinny

 

I have run 8.5 every day for the lat year. My TT went on in January of 04, and my build will start the end of January this year. I had the same plan as you, so I think you will be safe at 7psi, but be sure to tune to 8.5psi or 9psi to account for boost spikes. I tuned to 10psi, and have never spiked over it. hth

 

Well...a boosted engine blowing out has more to do with the air/fuel ratio as rpm and boost builds up rather than only the amount of boost that the engine sees. I know the stock internals can only handle so much pressure but with the right amount of fuel/air at the right time, it will be able to run at a more reliable and "safe" level before letting go than even a low pressure system with inconsistent fuel/air delivery...but yes I do believe after about 400whp the stock internals will give out. Heck even stock N/A engines can blow at anytime

 

I believe Charles from CJ Motorsports (Phunk) ran 467hp/ 451tq with stock internals without incident. He took it to the strip, dyno tuned it and did some racing with it. He said he had some doubt about its ability to hold up but it never failed him. Very well tuned with FCON & 1000cc injectors, I believe. He tore down the motor for a forged build up and I think there apeared to be no excessive wear or damage. I'm sure he'll chime in here.

 

I concur with that. When I had my Vortech installed I was at 350HP. It was amazing at first, but I did get used to it. I switched to the 2.87 pulley (415HP@11.5psi) and the car felt totally different. But I am getting to the point where I want more HP again.

Hey Bruce, once your car is finished I will definitely have to install cams to keep up!

 

They discountinued the fcon I thought?

 

FCON V Pro is still available. The PFC or the VPC was discontinued, I think.

 

Remember than Phunk achievede those numbers with the FCON Pro standalone. Also, I seems to be hit or miss with this motor. Maybe Phunk and others have stronger motors than others. Nobody can really explain all the variables at this point.

Just becuase one or two people are pushing the stock internals without problems....doenst mean that everyone can.

 

Agreed!

 

I do not believe my engine was a factory freak at all. I think that it only makes sense that experienced professionals such as myself are able to push a little more then what should be expected of from at home tuners.

with perfect state of tune my car never hiccuped. I used 100 octane gas to make my life easier and to help stabilize combustion... however what gas you use is not what effects the physical boundries of component strength... it does effect your tuning boundries tho. I think 450 rwhp should be the max target for 93 octane gas. I would expect a 93 octane car to make 450rwhp around 10 psi. Honestly I am not sure I would let a customers car leave running that boost... not yet, not until more time passes and I get even more comfortable with it.

I put on more abuse in the several thousand miles at 450+ rwhp than most 350z will ever see... so part of me says go for it... it all depends on the owner and driving habits. Road Racing? No way in hell. 385-390rhwp max I would run while road racing... and thats only after adding an external oil cooler, radiator, and thermostat. Road Racing this car with turbos would be like road racing a stock engine Integra Type R with a turbo... sure it will be fast around the track... for the first day out.

I had a scare where I thought that maybe I damaged my engine, after several thousand miles of abuse at my 467 rwhp i dyno tested the car again and after some tinkering i was only able to make 450rwhp at the same boost... then i remembered that somewhere in my abuse I pulled over and removed a little bit of ignition timing before a race... couldnt recall why i choose to but every now and then I would think I was taking my engine for granted.

My car at 467rwhp was not SIGNIFICANTLY faster then it was at 435rwhp.

Do not push it, leave it up to the professionals and time to find the limits. Someone will bother to break my record soon, and then someone will break theres, and it will continue to happen. But its not worth breaking your engine over... it could end up damaging components that you typically would not replace in a build up.

Before setting your HP goals, remember one thing. Most people that try to run 400 or more RWHP on stock engine daily will blow their engine within a year. Thats my honest opinion on it. This is due to lack of professional tuning. Dont trust any fool with a dyno, and if your a software developer, insurance underwriter, graphic designer, construction worker, dentist, etc... than do NOT trust yourself... You know what would happen if I was assigned to design a skyscraper and then it was built? What if I was elected to fill a cavity in a patient? It sure as hell looks easy from here! Yea... that wouldnt be pretty. If everyone was honest with themselves and their skill set.. and everyone did their job and their job only, less engines would be blowing up.

APS cars are an exception to the rule... their tuning solution provided with the kit is essentially idiot proof and the "tuning" required of it is hardly tuning. I am sure that people who "tune" the APS kit are merely adjusting your A/F a little bit and thats it. Mere turbo kit installers are not going to even know how much ignition timing the car naturally runs to know enough about how much they are pulling our or why they are pulling it out (or not pulling it out). Installers /= tuners.

Tuning cars is still a lot harder than the magazines or poor tuners act like it is. There is a LOT more to tuning than most realize. Newcomers focus on A/F. Well, A/F is hardly the most important part. I have seen way to many cars with wack *** lean A/F curves in crazy situations hold together for me to ever beleive that A/F should be the single most important focus of the cars tuning.

tuning is just like engine building with new comers. At first they are extremely intimidated by it... then all of a sudden someone explains it and they see it done on TV or in a magazine and its suddenly so simple and not worth paying an experienced professional. Then over the next 5 years you will start to learn, WOAH, it turns out you didnt know a damn thing about it. People always figure out why they blew their engines... I seen it happen so many times... like FOUR YEARS LATER the guy says... "ohhhhhhhhh well no wonder I blew my engine, I wasnt paying attention to _______ ".

I say, if your not a professional, and the shop your going to is hardly a concerned professional... keep the power to 400rwhp. How do you know if your shop is one that you could trust with pushing the limits a little? They will more than likely own a dyno, they will more than likely not use YOUR car for their R&D, and they will more than likely desire to NOT push your car harder for your own sake (something they actually care about). If your engine still blows up... well, **** happens... at least everyone did everything that could be done to prevent it within reason.

Merry Xmas.

 

You are dead on... possibly not in the way that you meant it. But you are definatly dead on.

 

Here in PR we don't have a 350Z Tunner, we have graet tuners but they don't mess with the Z (yet) I'm gonna install the Greddy TT (stock psi for now) and I decide to put Technosquare Greddy Reflash because I understand is the safest way to go if you don't have any tunner avalible... do you think there's another way to do it rigth or TS is the way to go?