I"m looking for some imput here. I just can't seem to narrow down why I'm seeing power fall flat from 5700rpm to 6500.

Here where some of the initial problems:

1 The origional air filter with the kit was way to small for higher boost applications, I put on a very large K&N unit that fits perfectly so there should be no starvation of air.

2 We tightened the serp belt which was squeaking upon startup, after tightening of course no squeak and more noticible power in upper rpm's

3 I've got a full AAM return fuel, 750cc injectors, walbro pump and emage ultimate tuned by SGP racing so there is no problems with fuel delivery.

4 I thought maybe the clutch was slipping (and maybe is) but I've got the JWT flywheel with the 300Z TT clutch. SGP says they use them all the time and are good up to 550rwhp or so. I'm looking at a ATS twin carbon clutch but maybe that would be a little overkill

5 I called procharger and showed them as well, they said that the blower the C2 blower does not really have an efficiency limit and power should be linear all the way to the top.

I have a built bottom end with 8.5.1 (should have gone around 9) low compression pistons with pauter rods

This dyno run was without the 50 shot of NOS which gives a little over 100rwhp and about 150rwtq. It's amazing how a little shot works when under boost.

The spike at 6500rpm is where my blower belt broke...lol...but I'm looking for some good feeback as to why I'm seeing flat power from 5500-6800rpm.

 

did you happen to change your cam?

 

Stock cams, valve, spings. I though it was this as well but Mark at SGP says that the stock stuff flows good up to around 550rwhp then starts to choke.

But of course this is only in reference to turbo engines.

 

^

 

sorry, i would have guessed it was fuel but i know your post ruled that out, you would know if it was lack of spark (it would sound like hell)
last WAG and i won't try any more, do you have a limiter of some kind that is "protecting the engine"

 

thats ruff, something is definetly wrong, your car should be pulling around 500whp w/out NOS

 

how much timing is being pulled at the high rpm's?

 

Did you keep gaining boost to red line ? Also ..I know the IC for the ATI is a good one , but do you know what it rated for ?

 

Not sure about the timing. The ECU was reflash by TC and they knew I was going to have the procharger. Then SGP did another tune but with Emanage Ultimate. I"m thinking too much timing is being pulled up top, that's the only logical explanation I can find because it should not fall flat like that.

 

boost was about 14psi but goes up to about 15 near redline. Procharger says the blower has no flow restrictions but this (my car) is the first built engine/high boost setup they have seen with this blower. I've seen plenty of stock Z with just 7 or 8lbs of boost hitting 360-380rwhp. That's why I"m thinking with the combination of the Techno Square reflash and SGP tune timing is greatly retarded (timing). I suspect after I get my Z back to SGP we'll find that timing can be greatly advanced throughout most of the rpm range. They do mainly turbo cars and turbo intake temps are much greater than intake temps of superchargers. Atleast I hope my theory pans out. But at over 14psi even with low compression pistons (8.5.1) I should still be seeing far more than 410rwhp w/o NOS

That's why I'm thinking it has got to be a tuning issue

 

well my thought was ..you might be running into some of the same problems I did at boost over 13psi . The IC can only flow so much air thru it . Mine tapped out at 13psi and the serp belt starts to slip , no matter how tight I got it . The preasure between the blower and the IC was MUCH higher than in the plenum . The serp belt couldnt keep a grip on the pulley any more .

There isnt any one in KC that can look at the tune ? Hate to see you drive all the way to Houston Tx. to find out its something simple

 

Kansas City has MC Racing. But are big into Mustangs, Vette's, trucks..stuff like that. Mark at SGP is cool as f*ck, I'd feel more comfortable making that trip than I would letting someone tune who did not know 100% for sure what they were doing. It's hard to tell just how much timing was pulled when Techno Square reflashed it the first time. And I can't blame Mark because at the time when he came up to tune it was freezing, snowing and we though the clutch was just slipping. But now I think it's really more of a state of tune, plus the intercooler. What IC do you switch too Booger?

 

www.icevex.com

Its a 12+4+31...3inch in and out . Very good price $290.00 thru www.rabbidperformance.com its the M-40 .

I know yours in an...in and out on the same side , so it wouldnt work with out total IC pipe redo . Call ATI and ask how much yours flows .

 

What happened on the dyno when you switched to a bigger IC?

 

I havent gotten that far . Block only has 200 miles on it . But Ive taken it to 5700rpm's and gained 1.5 psi more boost than with the other IC at that rpm level . The blower is breathing much better ...alot less restriction

 

Do you have a pic or measurements of your old IC compared to your new one?

 

https://my350z.com/forum/forced-induction/176943-finally-pulled-the-trigger-2.html

Scroll down to the pics of both IC's...little one is the old one...big new

old one I think is 24+8+3

 

wow...in your case that will make a big difference for sure. Keep us posted as to how it works out, very nice!

 

cliff? i hate you btw lol


and i'd steer clear of MCRacing, they won't touch anypart of my car unless its a non tuning dyno run

 

Have run a dyno run since you have gotten your bigger intercooler booger? Curious to see if you gained or lost boost pressure in the manifold