HKS IC was 28 X 9 X 2.5 - supports up to 400 hp

I have Stillen Test pipes - wont be able to use them ? and if not - why ? also what injectors should I get for that setup ? also I was planning to go with Crawford Plenum , any reason I shouldnt buy it since I plan to do TT set up ? I dont see any just want to be sure...
once I get my new Z and I brake her in , Im 99 % sure I will go for it... my biggest concern now are the headers.. I just Emailed boostlogic guys , since I dont see them on their site..

 

Picking out turbos simply because they are availible and cheap is not the way to pick out a turbo.

These turbos must meet your engines cfm demand at the boost pressure you intend to run otherwise your performance will be terrible.

If you can get a compressor flow chart for this turbo and post it here i can tell you if they would work or not.

The crawford plenum is a great idea for F/I cars as it flows air more evenly and at a higher rate ...also it helps correct the #5 and # 6 cylinder tendency to run leaner than the other 4.

Yes the stillen test pipes would be highly reccomended in any turbo application the less back pressure the better. This is why down pipes and exaust are so important in turboed cars.

The intercooler you choose must efficiently cool the cfm of air that you will be flowing through it otherwise it could just turn into a bottleneck in your system so to speak and cause all sorts of unwanted problems.

 

Unfortunately I was unable to find that flow chart for that turbo..
any other way to check if that turbo would be any good for my Z ?

P.S. Im not trying to pick a turbo based only on a price..
my main goal is performance.. Im going to meet with my friends later tonight so I will ask them about turbochargers...

 

Assuming you max engine rpm will not exceed 7000 rpm to run 6psi each turbo must supply a bare +minimum of 303 cfm @ 6psi each.

I can now see why the greddy kit uses a very large turbo like the tdo5 18g because @ lower boost pressures it is difficult for the smaller turbos to flow enough air for the big 3.5L VQ engine.

for example a smaller turbo like a td05 16gs trim (eclipse turbo i believe) can flow 300 cfm with peak efficiency at 12 psi quite easily however our motor would require much more cfm than that at 12psi as well as our rods would break.

The problem with the VQ is because it is a large motor it moves a large volume of air ...when you run boost you must run a large volume of air at a low boost setting because our motor will not take 12-15 psi where most turbos like to be.

You face the problem of moving a large volume of air at a low boost settings so you need a turbo that can flow a sufficient volume of air at much lower turbine speeds so you must therefore have a bigger compressor wheel.

observe the flow chart at 6psi look at the red dot see how far out of the efficiency range the demand is? It is very close to the choke line and keep in mind actual cfm may be more depending on numerous factors and there isnt much room for error here.

Any way you go with the Vq motor you are going to need a larger compressor wheel to flow the necessary cfm the engine demands.

 

link to manifolds scroll to bottom left

heres the link. thats a small ic btw. not really up to par for much boost. downpipes are the part from the turbo that connects to the cat so you would need them. also dont trust turboes off of ebay bc
1 no warranty
2 likely a rebuilt or defective turbo
3 those are very old school turboes nowhere near as good as newer ones.

 

SQUILL
If I know that a turbocharger supplies 505 CFM at 15 PSI , is there a way I could figure out what CFM it will supply at 6 PSI or 8 PSI without the chart ?
also little help on the chart you submitted ...
the red dot is at 6 psi - if so how do you figure that out ?
or is the whole chart at 6 psi ? sorry for the newbie turbo question..
and how do I figure out what size IC I need..

 

Sorry it took a while to get back to you

The compressor chart works like this the1 at the bottom of the chart signifies 1 bar of atmospheric pressure or the normal pressure at sea level. The 2 .0 on the chart indicates 2 atmospheres or 1 bar of positive boost pressure. 1 bar of boost is exactly double normal atmospheric pressure. So if normal sea level atmospheric pressure is 14.7 psi the 2.0 on the chart equates to 14.7 psi boost pressure

For ease of math 1.2= 3 psi 1.4 = 6 psi 1.6 = 9 psi 1.8 = 12 psi 2.0 = 15 psi

you can see this turbo makes 520 cfm at its chocke limit max at 2.0 line on the chart which is 15 psi for ease of math

The turbo that makes 505 cfm at 15 psi that u selected if very similar to this turbo that posted so more than likely it wouldnt be a great choice.

To determine the proper size intercooler take your max cfm in this case 606 cfm @ a 7000 rpm shift point and look to see if it is rated to flow that much air and how efficient it will cool that volume of air.

Selecting an intercooler that is too small will restrict airflow and cause pressure drop and unefficient cooling of the intake charge.

 

If you want to build a cheap kit you can get a used 14B for about $100 on the DSM boards. Now you need 6 440 injectors from DSM, get them cleaned by RC Engineering. Get a SAFC and J&S (or ask Technosquare to flash your ecu and buy 380cc injectors) You can easily get IC's from eBay that will support 500hp, just get one that's similar dimension to the GReddy IC. You probably don't want to cheap out on the turbo manifold, if the boostlogic one is good you could get that.

14B x 2 = $200
380cc injectors = $900
ECU reflash = $600
Intercooler = $500
Piping = $200
Exhaust mani = $1000 (?)
Downpipes = $500

So about $3900. It's a good price for a TT, but then a s/c kit cost just a little bit more and you can save all the headache of building your own kit.

 

most vital part is the manifold and the rest should be easy.

once you get the manifold.. you can get piping for cheap at jcwhitney.com and cut your own pipes then have your friend weld it. you can make your downpipe from the same piping. then the rest is just accessories... engine management, bov, wastegates, oil lines etc. As for the manifold.. if your friend can really weld, you should use pcv piping to mock up the turbo manifolds. After that just get manifold piping, make the flange, and welding it accordingly to the mock up.

With a custom kit you get what you want for cheaper.. you won't have a shitty closed loop wastegate setup like the greddy.

 

let me know how a 1.00 AR works out for you in terms of spool.......

As for IC pipes for $200.....sign me up man, I can keep your buddy very busy at that price!

what's a closed loop wastegate?

 

Using a properly sized turbo for the VQ35DE with a 1.0 ar ratio would probably be terrible!

 

when the wastegate is dumped back into the downpipe, from what I see is dumped right at the downpipe flange in a 90 degree angle which definitely disturbs the flow = big loss in hp.

if it's dumped 18" down from the turbo there would be minimal or no loss in hp.

 

If I went with a custom setup, I would personally go with the twin Blitz K3T turbos. Blitz uses Borg Warner KKK turbos, same turbos used in stock VW, Audi, Porshe.

 

Why ?? talk about oudated lousy turbos. I cant see why Audi/vw insists on using those turbos.

 

Guys, I'm following this thread with interest because I actually just bought the beginnings (manifolds, Garrett GT28R turbos, wastegates, RC440 injectors) of what may well become a custom turbo setup on my car combined with the FPR, the SS box, the intercooler, and some of the piping from my Vortech kit.

It may not work, but I'm gonna try it.

--Steve

 

+1
even though I know very little about turbos , I know those are crappy ones..

SQUILL , thx for explaning the chart , its all coming to me slowly..

what Turbos would you suggest if I was going to do it myself ?are tdo5 18g my only option ?
and where can I get them new , for a good price ?
I still didnt meet up with my buddies to ask questions...


zimbo
I see you got a G , how much did you spend on headers ?
thx

 

hee hee look im still awake @ 5:30am what a major case of insomnia!!!

Garrett gt28r is a perfect match. I analyzed the gt28r compressor map in the why is PE more efficient thread... very good choice in turbo very responsive because they are Ball bearing turbos rather than journal bearing.

They will spool very fast ..faster than the greddy turbos however are still able to flow the cfm our engine needs very efficiently.

They dont have the psi output that the greddy turbos have but this should only concern you if you intend to build the motor and run 550 whp+

Hardly cheap though but of the highest quality indeed!

If i had a compressor map of the PE turbos i bet it would be very similar to the gt28r.

Zimbo sounds like you have the beginnings of a good kit! Skidazzle is running the garrett gt28r turbos and i believe he dynoed 450+ whp however the kit he is running is $$$$$.

Building a quality kit for less $$$ than the kits out there sounds like a challenge to me it will be interesting if you guys do it and how it goes.

 

no they certainyly are not however the characteristics of them will need to be similar.

There are many base turbos to start from. A hybrid turbo is probably a good way to go as the space in the Z is limited.

For example using a smaller exaust housing with the compressor housing bored out to accept a larger compressor wheel.

Check out this web site http://www.mjmturbos.com/CarTurboDescription.html

you will get an idea exactly how many turbos are out there and the different hybrids based off of them.

There are many other factors as well a/r ratios, trim, exaust flange ect.

the main thing is the turbo must fit your exaust manifold as well as fit in the engine bay and be able to flow a good amount of cfm at low boost pressure.

these exaust manifolds that you can buy for the 350z what kind of exaust flange do they have? For example greddy takes mitsubishi turbos and then modifies them.

Even though the tdo5-18g is a mitsu turbo it does not have a mitsubishi exaust flange!

This might limit your selection unless you are having custom manifolds made to accept whatever turbo you have chosen.

 

I bought the manifolds, turbos, and wastegates from Boost Logic. They were in the process of test-fitting a kit when their "guinea pig" got restless and decided to go with a Greddy kit rather than wait. So they sold me a set of manifolds (they had three sets made and were on their 2nd iteration) along with the parts they were planning to use all at their cost. I'll be in communication with them re: fitment and such because they still have plans to make a kit for the 350z as far as I can tell.

--Steve

 

^ yea I spoke with them about the manifolds for Z , and they are still developing them.. told me to check back in a month ...

SQUILL - give me few hours to study what you just wrote ..