I decided to take my car to Z1 Motorsports Tuesday for additional tuning and it still doesnt look good. They did about 12 runs and ONLY hit 5.7 psi of boost 1 time. The other times, it didnt go over about 5.3 psi. Needless to say, my power is way down because of this. They did do several pressure tests on the entire system and found some vac leaks around the manifold as well as around the TB. They also pressurized before the blower. They put the car back on the dyno and similar results, no additional boost. I had the car dynoed at Z1 in Dec and ONLY put down around 232HP with headers, test pipes, Injen dual exhaust, Kinetix V4 plenum and the popcharger. They dyno with the Vortech SC, W/ the Kinetix manifold instead of the V4 plenum and w/o the popcharger ONLY yielded around 305HP. I had dynoed at Walker Dynotune in Bham, AL and put down ~340HP. So I think the dyno at Z1 is onsiderably low, which I have heard from numerous people. My A/F numbers couldnt be any more perfect. They are right around 11.5-12.0 across the board. A lot better than my original tune when the Vortech went on at a different tuner.

After several talks with Vortech, from 3 different guys, I am being told that my test pipes are what is killing the boost/power. I am being told that the test pipes are causing a loss of about 2 psi of boost. Since I am being hit hard with costs associated with the Vortech install, I am going to try to get a set of OEM cats to put back on the car.

Any comments are still greatly appreciated.

Zach

 

You will have to retune after the cats go on .

 

thats most unfortunate, i doubt the test pipes are causing it, i had test pipes on and dynod before and after and didnt lose any boost, i wonder if its the plenum, or i wonder if you got a bad blower. dont know what else it could be. hope you figure it out.

 

If he preasurized the system..he found all the leaks . I sure did . I lost about 1 to 2 psi with test pipes . i was at 7.2 psi with the 3.12 pulley . then put on Crawford cats and got over 9psi

 

I know. I am trying to work out an exhaust trade as well. Trying to get rid of my Injen SES and get the Stillen exhaust!

 

A bad blower was mentioned to me. I asked the tech guy at Vortech and he said that was highly unlikely. All I know is that I have about $7k invested in gains of about 70 HP (about $100 per HP). Very pathetic IMO. IIRC, there are NA guys that are dynoing at 295ish. Less than 10HP less than me.

The reason I went with the Vortech is because it was one of the most reliable kits out there, one of the cheapest as well and one of the highest HP producing kits and I have been about as unsatisfied as possible. I raced a stock SRT-4 last weekend and BARELY pulled on him. Also, I raced a friend of mine that has the HKS SC and he handed me my a$$. The HKS SC is the weakest SC kit out (based on HP numbers) and the friend has produced more RWHP than me with the Vortech. Its like the more $$$ I put in this car, the less the results I get. I think I have yet to get the desired results of any ****ing mod I have done. Hell, it makes me want to trade the car. My g/f just bought an SRT-4 for $19k. If I sold the Z for around 30k and bought an SRT-4 I would have about 10-11k to spend on turbo upgrades and motor work that would hand most any f/i Z its a$$.

Sorry for the rant, but I have invested over $10k in performance mods and this is the ****ing results I get!!!

 

hmmm. same here, no loss of boost, hitting ~ 8 lbs of boost with headers, test pipes and borla td exhaust. sounds like belt slipping or bad blower. then again im no mechanic.

 

I dont think the belt is slipping. 2 different shops have looked at this thing and neither think the belt is slipping.

 

draw a line with a white paint marker in several areas on the pulley making sure to hit the belt, run the car, then check to see if the belt lines up after the car is off. might have to crank it up a few times to get it to line up evenly but thats how i checked to see if my belt was slipping, you catching my drift ?

 

Great idea!!!

 

Zack, My first dyno was 285whp, last dyno was 394.4whp.

Before I corrected my belt slip noise problem I was only getting 5 to 7 lbs of boost.
The stock vortech belt design sucks. Make the change- it will cost about $45 bucks + belt. I have had no belt slip, noise or adjustment in 14,000 miles. Can anyone else with a vortech kit say that. for detail see my post.

This is the only way you know for sure-no belt slip.

I have vortech with 3.12 pulley (gutted cats) injen ses exhaust and 9.5lbs of boost.

gutted cats or test pipes will change your boost only a bit ( maybe .25-.50lbs) but the air is still moving thru the motor and is flowing with less restriction so you have a slight pressure drop. Overall the car will run much better without the cats.

If you have any questions about the belts let me know.

 

I can not hear any squeal which I think would be typical of a slipping belt. When I first had the kit installed, I was getting some minor shavings from the belt but I could not identify where those were coming from. Now, the shaving issue has almost stopped.

 

ah dont give up, youve got too much invested, its gonna be something small and stupid, youll figure it out, and believe me youll be satisfied. there can be some slipping without squeel. check that out.

 

I am going to go back to Z1 today to pick the Z up. I will have them check the belt to see if its slipping per backagains method above. If that still doesnt fix the problem, I have a guy that will give me his OEM cats and I now have access to a lift so I will likely try that route. If I put the OEM cats back on, wouldnt I just run a lot richer than what I am supposed to. I think now my A/F is almost a perfect 11.5-12 throughout the RPM band.

 

the test pipes are fine! there is something else wrong. hey timrod where did you get the belt/pulley do you have a link?

 

Zach,

For whatever reason, your car has never made a lot of power for the mods it has had on it, but don't get fooled into thinking every NA mod gets the advertised HP stacked ontop of the other mods. Lets look at the following example:
Kinetix V4 + 8rwhp*
Intake + 5
Pulleys + 8
Headers + 11.5
Cams + 15
Catback + 16
Test Pipes + 16

Total +79.5
*all numbers taken from www.stillen.com except for Kinetix V4 intake taken from www.kinetixracing.com

If anybody believes the above mods will put you over 300 whp, then I have a bridge to sell

If that were the case there would be many 300+ whp NA 350Zs running around out there and there are definately not many, if any. Chasing NA power is an expensive game, especially on this car which comes well tuned from the factory.

Your auto tranny has something to do with your lower numbers, but I can promise you our dyno is not the reason you made 35 whp less than at Walker. My stock 350 made 240/237 on this dyno without even an intake, some motors are just stronger than others.

Right now the issue is your boost level, pure and simple. Until you are making at least 8 PSI with a safe tune, the power numbers are really irrelavent.

See you this afternoon.

 

Thanks Lorca. I know that NA mods dont add up like they are advertised. I wish they did though!! As far as the dyno, I have heard from several forum members on here that it does read lower than other dynoes. Not sure how low, but I just know that Clint @ Autolabz told me I was puting down 343HP at Walker and the 1st dyno there I put down 305ish. I also realize a lot of factors come into play on the dyno. The fact that it was raining heavily Tuesday during my dyno runs didnt help out either Im sure.

Again, I realize that the main reason my #s are so low is ultimately because I am ONLY making roughly 5psi of boost. I know that I will be more satisfied once I find what I am losing. I realy want to run it at Steele to see what kinda times I am getting. I feel that that would be a lot better gauge of what gains I am seeing.

 

Zach,

Give it time. Z1 was able to find the problems with my vortech setup (low boost around 6) and gave me a great tune to 379. A buddy and I put mine on and we forgot one thing so you never know what it could be. We forgot the vacuum line to the blow-off valve. Are you going to the Stone Mt meet tomorrow?

Jeremy

 

So that was your car on the dyno at Z1, I was wondering whose it was but it never clicked..very clean! If you're staying in GA for a while let me know, I'm about 15 minutes from Z1 and I'd love to see your ride. If you haven't already found a set of stock cats I have my old set sitting in the garage.

Sorry to hear about the frustrations with your mods, I seem to run into the same thing with the exception of the APS kit. I've been where you are now thinking of all the possiblities with another vehicle, I always come to the conlusion that if I sold my car then saw someone else on the road driving it I would be pissed. You've come a long way from stock, don't let this one minor setback get to ya.

 

To anyone going to the meet tomorrow: anyone have a set of stock cats they want to give away or let go of for a VERY CHEAP price? I do have access to a FREE set but it wont be until the first of July.