Biochem7

iTrader: (8)

do you have OEM cats?

MrKaira

iTrader: (87)

yeah I do - i have considered getting hi-flow cats but an worried about losing too much backpressure. Think that will happen?

Also going to reinstall a KJR Pulley soon

Next big mod: heads/cams lol

Bahraini350Z

mmmm..... ok, let's put stroking and boring the engine out of the way!

mods list:
Nismo Cams
SSV
DC ss headers
resonated TP
Fuji Y-pipe
Apexi WS 3" catback
K&N replacement filter

Dynod 245whp@4th gear!!!!

could it be that I need a reflash?

Biochem7

iTrader: (8)

i think you mean you are afraid to lose exhaust velocity. I really don't know if changing the cats will cause that?

MrKaira

iTrader: (87)

I don't know about a reflash, but definitely a tune. Piggyback or a reflash should fix that. Without a doubt a tune though - and sell the SSV, put the stock lower and upper plenums on with the motordyne spacer, or get an APS tallboy or crawford upper plenum - two best plenums imo

maybe a CAI as well?

Bahraini350Z

tried the pop-charger. Power loss was fealt specially with our hot climate down at the middle east

Bahraini350Z

Does any one know if any of the JDM aftermarket ECU's will work on our USDM Z's?

Motormouth

iTrader: (44)

list edited

1) did you match exhaust sizing together or are you just buying peices and slapping them on?

you have a 3inch catback, but I think the y-pipe is only 2.5, headers are prolly 2.5, and no idea on TP, but hopefully 2.75-3. you need to match exhuast sizes to get the proper exhuast flow.

If you have all sorts of exhaust piping diameters, matching them up will do your powerband good.

2) there is no way you lost power with a JWT due to intake heat... the stock airbox is much hotter... did you not install heat sheild? did you actually dyno to see this powerloss?

if it is true, go for a CAI.

3) screw a reflash. with cams you should really have custom tuning. buy a Utec/Emanage ultimate, HKS Fcon, whatever your local tuner supports and use that.

4) put back on lower plenum, maybe take this time to install aramid gaskets since heat is a problem where you are. you might even want to smooth out the runners at this point, and clean everything up (lower, mid plenums) and buy a spacer or replacement upper plenum.

5) and becuase of the heat, maybe look into alchohol injection. that should substantially cool your intake charge, and is only 300-500 bucks for the kits.

oil cooler as well.

rocks

iTrader: (1)

I bet with jwt cams 9.1:1 compression, headers, intake manifold mods ill barley break 280 at the wheels. Going from 10.3:1 down too 9.1:1 is about a 10hp loss you generally get 10hp for each 1 whole point of compression. But i can run more timing with the lower compression.

Wired 24/7

iTrader: (2)

I don't think you should go with lower compression unless you're going F/I... just doesn't seem worth it.

You want peak cylinder pressure at like 15 degrees after top dead center, which should be attainable using pump gas and stock compression, and timing adjustment.

rocks

iTrader: (1)

I am going to turbo the car next year, thats why im using lower compression pistons 1 point drop in compression is like 7-10hp

97supratt

iTrader: (61)

On a Revup motor, those numbers are easily within reach.

You need some bolt-on's like:

-Intake
-Exhaust
-Headers (crawford)
-TP's
-Clutch
-Flywheel
-Crawford plenum
-Reflash or UTEC

That should put you right around the 280-290whp mark. JWT also has released cams for the REVUP motor which will yield another good 10-15whp.

Bahraini350Z

My exhaust is properly matched. The headers are 2.5 diam matched withe the TP linked to the Y-pipe which also has a 2.5 inlets and a 3" outlet that matches my catback.
One thing you need to know about the pop-charger, most people dyno their cars with the bonet open and the air filter sucks cold air unlike when you have your hood closed. The pop-charger can only be fealt at high RPM ranges, down low, power is lost (this is what I fealt really). And my heat sheild was fitted correctly (no chemistry in that)

But again, what's wrong with the SSV? Being frank, I fealt better gains with the old version of the Kenitix plastic plenum!

One last thing, isn't the dynoing must have been commenced with 5th gear? I did mine on 4th, could that also be why I have low reading?

Thanks

97supratt

iTrader: (61)

Throw the pop charger away and use the stock airbox with a aftermarket filter like my blitz LM drop in. Great gains, plus it keeps the heat away.

Yes dyno should have been in 5th for a bit more accurate of a reading but 4th wouldn't give you a big difference compared to 5th. The SSV usually doesn't do much for N/A applications, it actually loses power. I suggesting getting a MREV2 with the 5/16" spacer to see good results.

You should definitely get; headers, clutch, flywheel, stock airbox with aftermarket filter, MREV2 with 5/16" spacer, and either a UTEC or reflash. You should easily see 350 engine hp with all that plus your tp's and exhaust.

NETSHARK

Nismo Cams: Guess you need tuning to get full advantage.
SSV: as the guys said GET RID OF IT and use MREV2 + 5/16 Spacer.
DC ss Headers: don`t you think middle east climate won`t accept other than Ceramic Coated because of heat !! and i also recommend Crawford if you want additional POWER.
resonated TP: i guess thats the best thing you did, but am sure your car is rich as hell nowdays because of cool wave we`r getting in middle east.
Fuji Y-pipe: no comment on this product also its top notch
Apexi WS 3" catback: i guess its a good exhaust no need to change it
K&N replacement filter: Change it and get Injen Intake System, its the easiest to be converted to Short Ram when it rains too much outside

FYI: i`ve dynoed my car at Dyno Jet in Kuwait ( Actually dynoed it at two different shops) and i got 223 HP and something about 227 TQ, with only Nismo CAI, dynoed in the 2nd shop at 3rd gear and i got 242 HP then i told him to dyno it with 4th and i got 221 HP same results as the 1st shop. the Ratio of the 4th gear in 5AT is 1.00 in manual Z`s 5th gear is the closet to 1.00, and now after adding MD Spacer + UT-R Resonated TP i feel soo much difference in the power, it pulls more harder but actually its more richer, just hooked my AFR and am getting 11.5 at REDLINE, i dunno its because of the Testpipes or its because of UTEC in stock mode making my car more richer :1, but believe me i`ve tried the UTEC base map and am shifting at 7000 RPM it jumps at each shift like if am in a manual gear and doing clutch kick.

Bahraini350Z

Thanks man

Bini2

iTrader: (2)

FYI, a couple of the Engine Management Systems listed above do not have the ability to advance CAM timing (I know emanage and utec do not), you will want to tweak/advance that with your new CAMs. You'll either need an EMS that allows you to adv cams or send your ECU to Technosquare and have them advance your cam timing however far needed for the CAMs you select.

SergEK

1 pt in comp = 5% power loss from previous power out put

287hp vs 300hp motor losing 5% power will be different

When going FI however the lower cyl pressures from going a pt down are nice for lots of boost on pump gas

Old School

iTrader: (28)

Careful advancing timing too much. Lowering the compression will let you advance it a little more....but too much and you'll either get detonation or end up burning the sh*t out of the intake valves. I wouldn't drive the Z with 9:1 without a turbo....it will be hella sluggish.

Old School

iTrader: (28)

What ever happen to cam gears/sprockets? That's how I'd tune in my other cars' cams. Haven't put any cams on the Z yet, so if they don't do that on these motors...please excuse my ignorance.