[TT Stealth81381]

ok i am trying to decide what turbo's to go with. it is going to be 13g's or 15g's. what i am looking for is about 400awhp. do you guys think that it will be possible to make 400awhp on 13g's or do i need to get 15g's to make that kind of power. also i don't plan on boosting an abnormal amount to make the power. At the most would be 20psi. any suggestions would help

thanks

 

[Jeff Lucius]

Hard to tell about wheel HP. But the 13G turbos will probably not hold 20 psi to redline unless your engine volumetric efficiency is very poor. 15G turbos barely hold 20 psi to redline for most 3S engines. 400 wheel HP is like 500+ engine HP, so you might consider the 15G over the 13G if this is your goal (or just use 9B turbos and the dyno at AAM ).

 

[Lord Warlock]

If you've already done most of the BPU mods before adding the bigger turbos, it should be no problem reaching 400hp. (with either set of turbos) Choose 13G if you don't plan on going with bigger injectors and fuel management, go with 15g if you plan to upgrade the fuel system. I've got 13Gs and they pull alot stronger than the stock 9b turbos, and should easily be able to handle the 400hp figure. I believe it is pushing 425 to 450 now. Any higher will require fuel upgrades, the advantage of the 13g is you can drive normally with them until you decide you want to max out fuel mgt with the turbos.

LW

 

[TT Stealth81381]

so far i have a little more than bpu's and i am going to put a fuel system along with the turbo's. if i go with 13g's i am using 450cc injectors and s-afc. if i go with 15g's i am going to use 550cc and s-afc. i thought that 13g's could hold 20 psi to redline but maybe i'm wrong.

 

[Lord Warlock]

13Gs could hold 20 if the fuel system is strong enough. Not sure if it will go all the way to redline, but DR500s are rated to go to 16 with only a bigger fuel pump. dr500=13g sort of.

TEC says the 13g could boost as high as 26lbs, not sure if I believe that, but my goal was to run 15 to 16psi max anyway. I run 1.05 bar to redline in my 13Gs provided my boost controller would work properly. (still have to install the dsbc)

Lord Warlock

 

[[email protected]]

13G's won't hold 20 psi to redline. You can get 400 awhp out of 13G's fairly easily. My buddy's car dyno'd a little over 400 awhp with 9b turbos, so anything is possible . I'll probably have my 13G car strapped to the dyno during the winter time after a few more mods are done... I'm hoping for over 400 awhp out of it.

 

[TT Stealth81381]

i only plan on running everyday about 15psi, but when i go to the dyno i would boost as much as 20psi to reach my goal. i also forgot to say i was adding a fuel pump, hot wire kit, and i was also going to add kenne bell boost a spark....so we will see what happens.

 

[Shadowfax]

My question would be what fuel management are you gonna use? SAFC only- stay with 450's.
VPC/ARCII 550's
EMS- who cares- you've got it under control

I really suggest to most people running 550's if you can on any of the aftermarket turbos- 450's should have come stock on the car- and if you are really pushing the 9b's then you need 450's.

Take it up a step with the flow and I'd suggest 550's for 13G-15G cars- 15G cars that are running with different heads and cams- I'd suggest 720's. It doesn't hurt to have more fuel if you can tune it.

I know it seems kinda odd- the larger injectors cause tuning issues (mostly timing) but We've only got a little bit of decrease tuned in for the 450's on Jayson's car and we're still on stock turbos! We need to seriously start thinking about FJO's and other widebands as NEEDED mods- especially for those running hybrid ODB cars. Too many of us bite the big one for tuning issues.

 

[TT Stealth81381]

do you think that putting 13g's and 450cc injectors will max out the fuel system quickly.

 

[Shadowfax]

quickly no- and on pump gas- You'd probably be okay for a while- we're running Jay's car on 93 without the alchy at 17psi with 450's and it does well.

I know John M and Phalse and a few have ran 450's with stockers and with 13g's- 13G's are 450's aren't bad- but it's not a bad idea to allow for growth if you can

 

[Feral]

13G's could easily max out that fuel system. Here's my synopsis of what you need to know.

13G's ... hold 15-16psi to redline with healthy heads. Can spike over 20. Efficiency suffers over 12psi.

15G's ... hold 20psi to redline with healthy heads. Can spike to 25. Efficiency suffers over 15psi.

360CC injectors. Good to 12-14psi (limit of stock Fuel pump)
450CC injectors. Good to 15-17psi (limit of stock fuel pump + hotwire)
550CC injectors. Good to 18-20psi (limit of walbro fp)
660CC injectors. Good to 21-23psi (limit of denso fp)
720CC injectors. Good to 24-26psi (limit of denso fp + hotwire)

400AWHP will happen at about 18psi on either a 13G or a 15G.

So pick your fuel needs (fuel pump and injectors) and pick your turbo needs (I'd say 15G's are about the smallest you want for 400AWHP) ... and then go buy.

For you ... 15G's, 550CC injectors, denso pump (or hotwired walbro ... which would be loud as fuck), and a S-AFC or ARCII. The ARC is nicer since you can upgrade the MAF.

Also ... instead of the boosta spark get matt's coil upgrade ... it is MUCH better. Trust me ... I have both coils and the boosta spark and the spark is kind of useless.

 

[Twin Jim]

Feral what is the limit of the stock 360's with a denso fuel pump? And what if it was hotwired?

 

[BookEditar]

(or just use 9B turbos and the dyno at AAM ).

lol. am i the only one who thought this was funny?

 

[Shadowfax]

possibly- we only have a few dyno's availible- I think AAM is the only Dynojet we have right now.

Once GTPro get's theirs in- do you think the numbers will get more realistic? Cos I don't.

Some things just don't seem to always add up.

220WHP runs 13.55 in a 3800lbs car? Nope.
stock turbos hit 370+ WHP- yep. (I was told once that there was NO WAY stock turbos could snap a Kormex 18spline... Frank replaced it not 3 months later- and I wasn't in full tune)

If we wanna say the AAM dyno is inaccurate- then what is accurate? Numbers on a book? I see HP and times from AAM as being more closely related than stock ratings and times.

 

[Feral]

Feral what is the limit of the stock 360's with a denso fuel pump? And what if it was hotwired?

The injectors' inherent limit has nothing to do with the fuel pump. Granted with enough fuel pressure you can force more fuel through the injectors ... but fuel pressure is limited by the fpr not by the fuel pump so this does little for you. If you are only asking for 10psi out of your car through 360CC injectors ... it wont matter if you have the denso 343 with hotwire of the stocker ... you will have enough fuel. The same is true if you are asking for 25psi out of 360CC injectors ... again it wont matter what fuel pump setup you have ... you aren't getting enough fuel out of it and will have a dead engine.

Basically what I'm saying is regardless of fuel pump you should consider the limits I posted above as the limit of the injector. Now I was estimating 80-90% IDC with adequate fuel pressure to try and keep things safe. Just because one car somewhere with some setup can do something doesn't mean it's right for everyone. I just provided an estimated set of guidelines.

The safest way to do it is to start with the maximum boost you will ever run. Then decide what size injectors can supply enough fuel to safely run that boost at 75% IDC (this gives your injectos some breathing room). Then figure out how much fuel it takes to pump those injectors at 100% IDC (more than you ever need) and get that kind of fuel pump. This way your supply (fuel) is always larger than your demand.

 

[Feral]

possibly- we only have a few dyno's availible- I think AAM is the only Dynojet we have right now.

Once GTPro get's theirs in- do you think the numbers will get more realistic? Cos I don't.

Some things just don't seem to always add up.

220WHP runs 13.55 in a 3800lbs car? Nope.
stock turbos hit 370+ WHP- yep. (I was told once that there was NO WAY stock turbos could snap a Kormex 18spline... Frank replaced it not 3 months later- and I wasn't in full tune)

If we wanna say the AAM dyno is inaccurate- then what is accurate? Numbers on a book? I see HP and times from AAM as being more closely related than stock ratings and times.

My problem with the AAM dyno is in fact that I believe it underrates my car. You figure out how much horsepower it takes to push a 4000lbs car (race weight) 1320' in 12.01 seconds. It comes out to about 450-500AWHP which must be what I was making at 19psi on that run with one turbo on it's way in the shitter (it has since been laid to rest). In fact I believe with a better launch and a health turbo I would have been 11.8's on that run.

Then AAM dynos Minh's car ... which has a stand alone computer and a brand new engine (as opposed to my 120k mile engine running on an ARC2) and he only dynos at 450AWHP at 24psi on the same turbos ... and at 18psi dynos at 390AWHP.

Something doesn't add up. I personally believe the HP calculators to be somewhat flawed ... but I also wonder how minh's car (which I believe to be capable of 11.0x's if driven right) is only a few 1/10ths of a second slower than the AAM TD05 cars all running 600+ AWHP. There is some flaw here somewhere.

 

[Jeff Lucius]

List of the AWD dynos I know about - inlcuding many Dynojets:

http://www.stealth316.com/2-awddynos.htm

A bried analysis of HP-wgt-1/4-performance calculators - including my own using Road & Track published data - the LRT formula :

http://www.stealth316.com/2-calc-hp-et-mph.htm

My web page above also compares the results of the calculators provided with known 3S performance. A spreadsheet is provided with the R&T data.

 

[TT Stealth81381]

i see that i really have some choices to make. but from the looks of it i can make the power i want to make on either turbo's which is good. i have the parts for the 13g setup except for the turbo's and fuel controller. so i guess i just need to wait and see.

thanks

 

[KuJaX]

why dont you go and get dynoed right now? I'm pretty sure just with stock 9b turbos it is possble to have 400awhp. If your car is like your everyday driver just get the 13g's, and if you want, upgrade the fuel system. That is what is great about the 13g's is basically, however much power you want from them, you can just spend more money on fuel management upgrades.