I have made virtually all the decisions I need to in order to complete this crazy VQ turbo project. I'm not a turbo newbie, but I am new to VQ-T's. I want to do this RIGHT. I'm not afraid of spending the money. I just don't want to spend it twice by ditching my turbo because it was oversized or undersized. I want to apologize. I know this has been beaten quite a bit. I have slaughtered the search function over the past months... BUT I really want this customized to MY wants.

This is definitely different than upgrading turbos on our other cars... It was much easier to go the well-traveled ground of the DSM turbo market as well as the RB25...

So! On to the issues at hand.

Goal: 450FWHP. I don't want to tear the envelope to shreds, but I'm not scared of getting to the edge. I definitely favor later spooling turbos with larger power gains. Wheel hop sucks... the poly mounts help...

Already have/picked for the turbo:
Z32 370cc Injectors
Walbro 255 FP
Vortech Super-FMU
Apex'i SAFC2
Apex'i AVCR Boost controller
HKS SSQV BOV
Tial 38mm wastegate
Z32 MAF
Hybrid Custom 30"x12"x4" Intercooler
EGT/FP/OT/AF/Boost gauges

Already have not related to turbo:
MEVI
I30 5 speed LSD
UDP
Fidanza Flywheel
B&M STS
Exedy Stage 1 clutch (stage 2 when turbo is on)
Poly front/rear motor mounts
- Pathfinder TB before I put the turbo on...

Do you approve of my choices thusfar?

I do not have a reprogrammed ECU. Should I? I think with the FMU, I won't need it. Would it help?

The question is... WHICH TURBO? I would really like a GT30BB, but it better be the best damn turbo for our beloved VQ. The price is a bit steep, but if it's worth it... I'm going for it. Give me YOUR IDEAL GT30 SPECS!! Should I stretch it and go to a GT35?? *sigh*

I considered a T4/60-1. Is the GT30BB worth the extra $$?

T4/60-1 Specs:
- T04S Compressor
- 360* Thrust Bearing
- .63 A/R Turbine Housing
- Stage III Turbine
- .70 A/R Compressor Housing
- 60 Trim Compressor Wheel

Is there any other turbo that would be BETTER? Price isn't a HUGE consideration. It does factor in. I'm doing this RIGHT!

I REALLY want to get the RIGHT TURBO! I want it to be able to handle the forged internals (for 550+HP) I'm going to throw at it when I rebuild in 6 mo. - 1 year.

The money's burning a hole in my pocket. I need to spend it before my wife convinces me to use it for her Spyder GST -> GSX conversion!

That about covers it. I GLADLY welcome ANY input. Again... I WANT TO DO THIS RIGHT THE FIRST TIME!!

 

The T4/60-1 or the GT30BB will both make well over 450fwhp, assuming you have upgraded your internals to match the higher levels of boost. You may want to think about a few extra things that could cause difficulty with your car:

Injectors. 370cc is kind of low for 450fwhp as MardiGras will tell you. You may want to go to 440cc ones or as high as the Nismo 555cc's to stay in a nicer range (ie, not 80-90psi+ .. Mardi's running a 3:1 FMU disk with his 370ccs. If you put up 20+psi, that's 60psi on boost alone)

Fuel computer / ECU. Most of us have heard about JWT's dealings with other Turbo maximas ... If you do decide to upgrade your injectors higher than 370cc, you WILL need some sort of device to manage them. JWT? That's the most plug-and-play device we have. Also one of the more expensive ones. gReddy eManage? That's another one, I don't know if it will support 555cc, but I'd guess it'd let at least 370 & 440cc's run nicely.

As for the rest .. I don't know much about the upgraded internals. If you're going full blown, pistons, rods, JWT cams and Cattman headers would be a nice start

 

i just bought a garret GT3040R, but havent installed it.
I have a t4/to4e .71 backside .60 comp now (if anyone wants to buy it [starts spooling around 3000 full boost about 4500])

Garrett GT3 series turbos all have a t3 compressor section. They should spool a little quicker than the T4/60-1, plus i think the 60-1 is overkill. And hard hitting boost is cool if you want to turn big dyno numbers, but remember, you have to keep those wheels on the ground. I can lose traction at 60+ if i do not modualte the throttle correctly. get a GT series.

Also, get rid of the AF gauge and get an oil pressure gauge.

 

Well the greddy emanage supports up to 150% of stock fule injector capacity. And ereet the cattman headers? Why he is going turbo, waste of money. As we have seen with Hals setup the factory internals can handle 450 whp, I think if you are wanting to push the envelope then go with the stock internals then and if ya blow it ya blow it, you were gonna spend the money on new guts anyways. and just like on_alert said, unless it is a full sweep AF gauge get rid of it, only good for a light show. Good luck hope ya make yer goal

 

Keep your transmission in mind.

 

I still would like to know if that is 100% true.....from what I know I still think its a rumor

 

A Z32 MAF won't work unless you get the JWT upgraded ecu. You can have JWT program your ecu based on the Z32 MAF and whatever injector size you choose.

 

Well, the rebuild is scheduled for when I blow the engine... That's when I'd BUY JE pistons etc...

I haven't kept my transmission in mind. What did you do to build yours up, HlH? What setup DO you have anyway - minus the N2O.

The A/F is a light show. I have the SAFC anyway. I do have an Oil Pressure gauge - forgot to mention. :/

So, GT is the decision. GT30 or GT35? I'm getting excited. Knowledgeable replies are a breath of fresh air from the 240sx and Eclipse message boards.

 

and thats where I think Corey(Redmax) will have the most problems with his setup trying to run Emanage and Z MAF....like I've been saying I think people are putting too much faith into Emanage being a FULL support system, but thats just my $.02.

 

I would go at least a GT35, 30 is a little small.
what a/r are you getting on the backside?
about the z32 maf:
at 10psi, i am using 95% of my stock maf capacity. The emanage does have a simple correction for larger injectors and and a larger maf.

Personally, the way i plan to tune it is to use the optional MAP sensor and use that to kick open extra injectors under boost, no fmu needed.

I have the emanage, but not the map sensor, i would also get the profec e-01 boost controller, becuase it works very nicely with the e-manage, doubles as a data logger and the signal from the EGT warning gauge can be looged on it as well, these will aid greatly in tuning.

Another thing. If you are going to get the GT3035R get it from cheap turbo.com tell them christian with the turbo maxima reffered you. If you call and ask for Ken, he knows his ****. I think the one I bought came to 1800 or so, but i got a bunch of little goodies like v-band, polish, hpc coat, etc. I haven't found a lower price anywhere.

 

that will be an interesting setup, but why did you choose to go with extra injectors as opposed to just upgrading CCs??

 

this way, i can maintain the stock fuel curve (more or less) and still have plenty of fuel under boost. If i went crazy w9th the injector size, then idle would be way off and i would need to mess with tuning even more.

 

How about a GT35/40 with a 0.63A/R? I can get a real deal on a new one, but I thought it was a bit of overkill. I could run low boost and just spool around 3800.

I like the idea of extra injectors in lieu of 555's. Can you elaborate?

 

As far as turbo reccommendations go, i would just call cheapturbo.com, ken knows alot. But i assume he is going to point you at the GT3040, which is basically a GT3035. There are so many combinations that I just left it to the pros. They are good guys there and they know alot about what they sell.

As far as using the extra injectors, I havent gotten into the meat of it yet. But the emanage manual allows you to use a MAP sensor if you exceed the stock MAF or MAP sensor. Since the fuel curve would be more or less stock off boost, the emanage unit can be programmed to open the additional injectors when there is positive manifold pressure. The sub-injector map is a 16 by 16 map (MAP duty by rpm), where you fill in the sub injector duty at all these points. I am not 100% that it will work that simply, but I am not tuning this myself either (i hope). I would like to use the ignition altering harness as well, i already have it, but i am not sure it will work with our distributorless setup. I really hope it does though, i just need to find out exactly how the emanage alters the signal...

-ctn

 

I've only seen one exhaust manifold from a turbo maxima. I believe it had the stock headers, into a modified Y-pipe which split back into the turbo. Which would mean aftermarket headers would still provide decent gain.

This guys talking about 450fwhp. Aftermarket headers on that much exhaust flow is BOUND to do something, unless you have a turbo setup redesigning them (which as far as I know, nobody does..)

As for the injectors. 370cc's will work with the eManage. They'll also work with a STOCK ECU & aftermarket FPR. From that information, I'm gathering that the 440cc's and possibly 555's will work as well. No guarantee's but hey, I'm just throwing out ideas. A JWT ECU should function just as well, if not better. It's a little more $ though.

One further note for the eManage -- on_alert posted that he may be having trouble with the eManage w/20psi setup. With my experience with local shops and the eManage, this is either because it's difficult to tune, or that it will cause strange problems. I'm guessing the first one, because when I inquired with several local shops about tuning an eManage, nearly every one of them cringed at the mention of it. Apparently not many people like working with them

 

I am already researching X-headers... We just don't have a very good selection juswt now...

 

build your own headers. ;-)

 

123456

 

Just a side note, the A/F ratio guages are very innacurate IMO, if you got the $ use a wideband o2 to perfect the setup once done.