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Hmmm doing my own HUGE turbo conversion myself at the moment.

GT35/40R, custom high mount manifold, plazmaman inlet plenum, wolf 3d v4+, tomei fuel pump, 550cc injectors, and all the other usual's. All i'm hoping for is 250rwkw, though it seems you guys/gals are getting more out of stock engines than i thought you'd wanna push. Has anyone got any dyno's in shootout mode??

Also as i've got the head off atm, would you guys/gals recommend standard head gasket, or 1.2mm or what??

Hmmm doing my own HUGE turbo conversion myself at the moment.

GT35/40R, custom high mount manifold, plazmaman inlet plenum, wolf 3d v4+, tomei fuel pump, 550cc injectors, and all the other usual's. All i'm hoping for is 250rwkw, though it seems you guys/gals are getting more out of stock engines than i thought you'd wanna push. Has anyone got any dyno's in shootout mode??

Also as i've got the head off atm, would you guys/gals recommend standard head gasket, or 1.2mm or what??

Why not have a look at the link below to the turbo upgrades thread:

RB25 turbo upgrades

Find a member's car with around the power output you are looking for and see what turbo they are using...then check the dyno graph to see if the power delivery will be acceptable for you. There are pages of info on setups that are already in use by members.

I have the 3540 and it is too big if you want 250kw.

Cams will fatten up mid range depending on what you run, 256 with 8.5mm lift are most common on Rb25 and work well. but you didnt mention anything about replacing valve springs, highly recomended to do this before installing camshafts, as standard springs are at their limit at about 22psi at 7000rpm. When you oder cams order RB20 inlet cam so you can fit adjustable cam gear.

Hey guys,

Here my current setup that dyno'd at 403whp on an RB25DET w/ garrett GT30R, avc-r is turned off and using a 1 bar spring on the external tial gate.

Internally stock, but i am in the process of buying tomei cams, and 1.2 headgasket.

My dyno is pretty close to phee's.

You guys think the cams would aid in boosting earlier?

RB25DET Motor Swapped from an 1994 R33

MINES Tuned 300ZX Z32 TTurbo ECU

Aeromotive Fuel Pressure Regulator

Aeromotive Liquid Filled Fuel Pressure Gauge

Greddy Hi Polished Intake Manifold

Greddy External Oil Catch Can

HKS SSQV BOV

HKS Type S Front Mount Intercooler

Garett GT30R Ball Bearing Turbo Hi Polished

Thermal Wrapped Turbo Blanket

Tial Wastegate 38mm

- Externally Dumped

Custom Top Mount Stainless Steel Exhaust Manifold

Kinetic Motorsports 550CC Injectors

Keeplabs Custom Billet Top Feed Fuel Rail

Keeplabs Custom 90mm Q45 Throttle Body

Keeplabs Custom One Piece Driveshaft

Keeplabs Custom Intercooler Piping

Keeplabs Custom 3” Downpipe (Heat Wrapped – 1 02 bung, 1 extra bung for Wideband)

Keeplabs Full AN Fittings, Stainless Braided Fuel System

3" Stainless Steel Catback Exhaust

- 3 Inch Straight Through From Turbo

Z32 AFM

Walbro 255 Fuel Pump

49889675.dynosheet.jpg

Hey BezerkR32!

Which tomei cam is best for my current setup listed? Lash type 256 with 8.5 lift?

I don't plan to boost higher than 1.25bar, and i'm probably going to keep the stock redline, until i can afford to dump more money

My block is stock at the moment.

My current plan was to buy and install the following:

Tomei camshafts, cam gears, 1.2 headgasket, timing belt, and your new recommendation for valve springs.

I'm also trying to figure out the part numbers on Tomei website.

If I'm going with the PROCAM + Adjust pulley (Alminium IN,EX) package, wouldn't the package be specific to the RB25DET? Being that the cam gears will fit on the camshafts? Do I specifically have to tell them that I want an RB20 inlet cam? **just a lil confused**

Lastly, for the Valve Springs, should I go with the 8.8mm lift?

EDIT: I forgot to mention my engine harness / ecu setup. My car is an 89 HCR32 GST-T. The engine is an 1994 RB25DET using the stock rb20 engine harness. vvt is not hooked up. injectors are top fed. The ECU is from a Z32, Mines Tuned. Using piggy back SAFC2 to control af.

Is vvt THAT important? What kind of performance am i losing here??

Thanks for the help!!!

Cams will fatten up mid range depending on what you run, 256 with 8.5mm lift are most common on Rb25 and work well. but you didnt mention anything about replacing valve springs, highly recomended to do this before installing camshafts, as standard springs are at their limit at about 22psi at 7000rpm. When you oder cams order RB20 inlet cam so you can fit adjustable cam gear.
Edited by 604cefiro

i still dont get the graph, the more i look at it the more odd it seems.

On one side its either been deliberately tuned to be laggy, ie no ignition to get it going...

Yet, on the other side its making a reasonable amount more top end power than anyone else has before @ 1 bar with the 550/600hp Garretts...

Hmm.. Cefiro, do you have a dyno sheet with the AFR's on it?

Also first thing i would be doing is getting a better ECU.

If your on a budget and you have to choose between cams and ECU, ECU is the pick there

I'll try to dig and see if i can find the sheet with the AFR's.

I remember it not being a graph, but a print out sheet with AFR's at certain rpms and boost.

The problem right now is my wierd engine harness setup.

I'm using my stock RB20DET engine harness connected to the RB25DET. Since the pins on RB25 ecus are different than RB20 harness, i opted for a Z32 turbo ecu that plugged right in.

Besides the fact that i'm missing VVT, the car runs awesome and AFR numbers are good. Although, lowend power is teh sucks.

What ECU / standalone management can I run to control the RB25 on my RB20 harness?

Will I have to go and source an RB25 engine harness?

If you were wondering why im not running an rb25 harness in the first place, it was because the place i bought the motor from did not have the harness with the motor (scored the motor for a crzy price).

i still dont get the graph, the more i look at it the more odd it seems.

On one side its either been deliberately tuned to be laggy, ie no ignition to get it going...

Yet, on the other side its making a reasonable amount more top end power than anyone else has before @ 1 bar with the 550/600hp Garretts...

Hmm.. Cefiro, do you have a dyno sheet with the AFR's on it?

Also first thing i would be doing is getting a better ECU.

If your on a budget and you have to choose between cams and ECU, ECU is the pick there

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