The Z's compression really isn't that bad for FI. I've seen tons of Turbo and S/C Integra Type Rs (10.6:1) cr running 9psi for years. It's all in Tuning. You need the proper fuel and timing. I ran 6psi on my Prelude for a year. The H22a4 is known to have very weak internals due to the ringlands. I upgraded to a Hondata 2b setup with 440cc RC injectors. My A/F ratio was a 12.5:1 the entire rpm band and I never had a problem. My compression tested the same as the day I put the S/C on my Prelude.

Another thought is for those that are wanting to boost 1 bar, adding forged pistons and rods really isn't that expensive, and sleeving really shouldn't be required to run 15psi. I think 8-9psi daily and 1bar at the track on 100 octane should be fine.

 

What et's where the S4's running?

 

evil350Z said...
I'm not sure how others feel about this statement, but I would tend to agree... 1 BAR+ is a lot of boost without changing anything inside. However, if I remember my conversion correctly, 1 BAR = 14.7 psi.

The GReddy kit was set at .45 bar (or 6.6psi). I think the motor could handle that all day long without a problem, and possibly as much as 9-10lbs of boost... still less than 3/4 BAR

$7K would be steep for 350HP at the rear wheels, tho. If the kit could be had for aroun $5K for that horsepower or up to $7K if you were getting just over 400rwhp, then I'd be in.

I don't need a lot more power, but like VandyZ, it doesn't hurt to have a little insurance. While it is awesome to drive the Z in the curves, you will just as often encounter someone who wants to test you in a straight line... and 350-400 at the wheels should be enough to handle many of the cars that you'll come across.

 

I am pretty sure they are forged internals from what my dealer said, but we all know about thier knowledge.

I have the Service Manual CD handy, would it be in there?

 

I dont think greddy is gonna sell us a turbo kit that blows up on you.

 

Hello just wanted to join in this conversation...

Yes, I believe Nissan VQ internals are forged. It's the high compression that will intervene with the combustion... careful tuning is required for high boost.. especially fuel/ignition and engine management. I remember someone in the maxima.org forum ran a single T system and provided around mid to high 300 hp range with a full 3" exhaust... I know it is feasible with our VQ35DE's.. probably we will see higher numbers with the extra 0.5L increase just as long as the turbo does not go boost crazy. I doubt anyone will TRY to go boost hungry for now, so low comp pistons with forged rods are out of the question... Timing retardation is essential though... it will lower the chances of knocking as well as detonation.

now.. if someone can incorporate a low comp system just like the Gloria/Cedric/Cima VQ30det... now we're talking.

happy and safe motoring.

 

Actually, the Z can withstand the tt setup. Power Enterprise is running 460hp with stock internals. So if Power Enterprise can do it, so can Greddy. I think Greddy isn't really trying, so they can get CARB passed, then they will show the hp with high boost.

 

I'll tell you right now that with my experience with the VQ motor (in my maxima), I will probably be one of the first guys in a Z to push boost over 10psi. I have a lot of confidence in this motor from what I've seen and experienced thus far, and just like what has been recently mentioned, tuning is EVERYTHING. There is currently a maxima on a completely stock motor running 15psi AND a 30 shot of nitrous. He ran a pass of 11.9@117 a few weeks ago...again TOTALLY stock motor that has lots of tuning in it (including an independant timing retard system). It can be done.

 

Also, don't forget greddy is running the factory exhaust and CAT which, as I'm told get as small as 2 inches at some points.

 

They're not running the factory exhaust, they're using a prototype dual EVO exhaust system.

This is what that car is running; they're pushing 350whp with:

GReddy:
Prototype Twin Turbo Kit with:
-Twin GReddy/Mitsubishi TD05H-18G Turbochargers
-Twin External Type S Wastegates
-One off Stainless Steel Turbo manifolds
-Twin Airinx AY-SB open element air-filters
-Prototype Front-mounted Intercooler
-3 Row Type 23 (H292 x W600 x D115mm)
-Dual inlets end-tanks to a large 80mm single outlet entank.
Engine Control:
-e-manage (piggy-back ECU)
-PRofec e-01 electronic boost controller and e-manage programmer
-Full Auto Turbo Timer
Exhaust :
-Prototype Full Dual Evolution Cat-back exhaust system (dual 60mm)
Brakes:
-GREX/ Alcon 6pot Calipers with slotted 360mm rotors (light-weight)

Others:
Injectors:
-RC Engineering 440cc Injectors
Suspension:
-Tein HA Coil-over suspension kit
-Tein EDFC damper controller
Wheels:
-Volk Racing GT-C Gun-metal F 19 x 8.5, R 19x9.5
Tires:
-Nitto 555R F 235/35/ZR19, R275/30/ZR19

 

555r is the DR right?

They make the DR in a 19 in ? I was told I couldn't get them in my 18 in!

 

Are you sure about the 440cc injectors? That seems too small to me. I would think that should be 550+

Mark

 

Yeah you're right, I wonder where I saw that.

 

That's, a sweet looking exhaust set up.

What is that an H-Pipe true dual?

And wat is it jet hot coated?

P.S. Stock cats with a resonator?

 

That exhaust is Sweet! add in some high flow cats....NIce

 

There seems to be some questions goin on here reguarding the internals of the VQ. I can tell you that from my experience, Nissan uses forged cranks and rods but cast pistons. But the pistons are of very good quality and they will hold just as much power as the rest of the engine. here is a picture of a VQ35DE rod and piston from a 2002 Maxima. The piston has the same casting marks as all of the other Nissan pistons I have seen.
It has been mentioned already that someone put down 430fwhp on a Maxima (original stock block VQ30). That was Matt Pelto who was the same guy that took that VQ35 block apart and snapped that picture. He and I both speculate that the weakest parts of the VQ35 are the block itself and the rods. Within the next few months I intend to find out if the VQ35 can hold the 400+ fwhp. So far it has held 313+ fwhp and 337 fwtq with ease on a dry nitrous setup. Even the stock clutch is holding out perfectly.

 

I dropped down to take a few pics of it at IAS...

 

pipage

 

What about lag time.A twin turbo setup i would think there would be alot of lag i might be wrong

 

That's not what the new Turbo magazine issue is saying. The Greddy 350Z is on the cover and it says 334 whp @5.X psi

It's still good. The article says its 89.XX more wheel hp than what it dyno'd stk.

Hopefully they'll be able to squeeze out a few more horses.

Also, that maybe on pump gas. If so, then 110oct and more boost will yield nicer numbers.