wes, i was wondering about that as well. i believe act just released a hd kit for the z. if you have had any expierience with tilton, how would you compare the two? i really dont want to have to replace the next clutch more than once a season if thats possible.thanks jason

 

I think what you're referring to is the number of maxima people who've blown their trannies because they ACT did such a good job of transferring the power from the engine to the tranny, but the tranny just couldn't take it.

 

Bldrz:

Just curious WRT to the drop ping efficency above 18psi.

a) Has the ECU been re-flahed to allow for 100% TB opening.
I read somewere (I thing TS) that the OEM flash limits TB opening at WOT and higher RPM.

b) have you tried a bored TB, I know 350EVO offers one, maybe the TB is a flow choke point? I know on blown Mustangs this is almost always the case at higer boost levels.

 

Bldrz:

Also have you coinsidered the ATS Carbon/Carbon?

Easy to slip and good for 900 crank hp.

 

SQUILL,

Correct me if I'm wrong here, but there is a problem with your version of the compressor flow map. Since he's at 5200ft, you'll need to use ~12.152psi as atmospheric pressure. Your PSI(at the manifold) increments need to be adjusted upwards.

 

bldrz,

What RPM are you seeing MAX psi at?

Can you give me a rough guess of psi at 2000, 3000, 4000, 5000, etc.?

 

yes you are correct i did not modify the chart for altitude. 2 bar on the chart would be double atmospheric pressure or 12.53 psi of positive boost !!! So boulder z you might want to consider boring out the compressor housing for a 20g comp wheel as your turbos are clearly running out of air @ 22 psi.... based on the chart if you were to run these turbos at 25 psi your gains would be negligable at best.

 

Also, what VE's are you using at those RPM? Also, what desity ratio are you using? 0.0730lb/ft^3 at MHI standard temp 76.3F and pressure 14.5025psi? In this case, I used 5200ft and 85-degrees to calculate the density ratio of 0.0603lb/ft^3.

He's only seeing a little over 12psi atomospheric pressure at 5200ft, so his turbo wheel speed is going to be much higher to make the same 24psi. Once you start approaching these higher wheel speeds the airflow dramatically drops off as you increase the RPM and efficiency suffers as bldrz dyno is showing.

I'm not sure what VE to use because of his cams, but using a 100% VE, I get this...

 

What about Exedy Carbon/Carbon? I don't know what the power handling capabilities are though.

 

bldrz,

You could definitely improve your VE from 5000+ by tossing the single&dual chamber plenum design. After looking at these pics, you could do MUCH better by just fabricating your own single chamber short runner design.

 

G3po, we haven't reflashed ecu but do not appear to have a problem their. also running stock tb. i will have to take a look at a bored version. we will give ats a call. thanks jason

 

ice, boost comes on fairly linear. take a look at the two dynos above. max boost reached much earlier at higher boost levels and then maintains with slight variation in psi. sorry i cant remember the boost levels throughout the rpm range. we made alot of runs with multiple changes throughout the evening. i will try and take better notes next time.thanks jason

 

Would you say you hit 24psi at 4700-4800rpm?

That dual surge tank piece in the lower manifold is KILLING your top-end. It needs to go. Your cams did help VE I'm sure, but someone needs to fabricate a single plenum lower to make one large single plenum intake manifold while looking OEM. Or you could just replace the whole thing with something easily fabricated like SpeedForce Racing did on this manifold($1100):



Personally, I'd take that route before tossing the 18Gs and going bigger.

 

ice, if i remember correctly that is where we peaked(@4800) and then it seemed to begin to fall off slightly. do you think the plenum above could flow that kind of air?? obviously it would be more efficient than our current setup but do you think we would benefit from a larger one?

 

That plenum is from ssr engineering and for high boost levels it would probably flow way more air than the stock plenum design.

As i commented eariler i believe the choke point is the tb/plenum at this high of a boost level.......lets see what icy thinks.

BTW there is a thread here on that plenum try a search for ssr engineering or check out their website http://www.ssr-engineering.com/

I believe it is the only plenum which replaces both the top and bottom.

 

SpeedForce Racing is the REAL fab shop, SSR is just the middle man that contracts through them and puts their name on it.

Might as well buy it from SSR though, since it's $105 cheaper. However, I'm sure if you call SFR up at (619)328-4012, they'd match or beat the price.

http://www.ssr-engineering.com/produ...kemanifold.php
http://www.speedforceracing.com/prod...y_g35imani.php

 

What would be sweet is if the SSR plenum were drilled , near the runners to accept aux/boost injectors. I woudl be a bit concerned over inadeqaute fule distribution by spraying all the way out "pre-TB". At least the OEM Plenum was not designed for Wet distribution. I don't know if SSR has ever considered this alternative. Could be a slick package , were the OEM inejctos could remian intact nad 100% of the Forced load were compensated by well placed boost injectors.

 

I'm not 100% sure on the stock manifold being the culprit, since there are other factors involved. Supposedly, the 350Z engine ALONE, ie no drivetrain/ehaust/etc., basically on an engine stand dyno, has 100%+ VE from 4000-6300rpm and even 105% VE at 5600rpm according to the SAE technical document I have. However, from the actual dyno I've seen, it's about 95%@5000, 85%@6000, 72%@6600, so there is something else besides the intake manifold holding back power, even in NA form.

So, that means you could have something else hurting VE, but if you've got plenty of access to a dyno, you might rig up a few cheap pressure gauges and find out where the airflow restriction is:

1)post turbo
2)post IC
3)post MAF
4)post TB

If the drop isn't significant, you'll have the manifold and heads to try and improve upon.

 

I have ANOTHER theory, but this one is going to take me awhile to figure out.

bldrz,

Do you know any other specs on the JWT cams besides what's on the website, ie duration is 260-degrees, lift is 10.9mm, and intake advance is 2-degrees?

Also, you don't have a P0011 or P0021 DTC, correct?

 

how much boost were you able to run with the 440cc injectors and what fuel pressure were you using