I searched, but didn't find the info that I needed. I have recently acquired an S5 turbo + manifold with a ported WG and was wondering what the gains of installing the S5 setup onto my current S4 engine. I know the S5's make more HP, but is that because of the rotors compression coupled with the turbo or what. Basicly if I swap the S5 turbo on what will I notice in terms of power? Thanks.

 

less lag, ie turbo spools up quicker. top end is about the same

 

Quicker spool is debateable. The S4 turbo uses the twin scroll flapper to attempt to accomplish the same thing. I prefer the S5 turbo mainly because it's a better design, and there are less things in the engine bay to deal with (twin scroll actuator & solenoid). Also, performance wise, the S5 wastegate is 5x larger than the S4 before any porting is even done.

95% of why the S5 turbo is rated at 200hp vs. the S4's 187hp is because the S5 runs 7.5psi stock, while the S4 only runs 5.5psi. This is due to the S5's turbo duty solenoid (bleed-type boost controller) and the ECU. The wastegate actuators are exactly the same. There's no difference in hotside A/R either. Both are 1.0; I've even measured and calculated it.

 

Thanks for the info guys. I am running ~10psi on high boost so I will keep the S5 turbo as a good backup. Does the S5 turbo combo hold boost better? I find my boost will drop from ~10 down to ~7psi at redline.

 

Nope. The compressor (which is identical on S4s & S5s) is just too small / inefficient to hold boost up to redline.

 

Put it on and try it out. See what the butt dyno says.

Also, since you don't have the heatsheilds I would recommend you get a turbo blanket. Might as well wrap the downpipe as well. This combo will help get rid of the turbo lag.

 

Are the manifolds different? And if so, what are the differences?

 

S5 is fully divided, while S4 uses a flapper door to block off one of the runners on the hotside under 2700 RPM.

 

Can you run an S5 turbo on the s4 manifold? Or does the S5 turbo have to be on the S5 manifold?

 

just a question. Is my turbo a series 5 or 4? http://s155.photobucket.com/albums/s288/Mendez_86/ does this one need port to flow well on 14PSI??

Cheers, Dave

 

Omix, no you can't mix s5 turbo with s4 turbo manifold vise versa. They just don't interchange since flange difference.

ganador, you have a s5 turbo. It's not wise to run over 12psi on stock turbo. But to answer your question, it does help to port it more.

 

whats wrong with running over 12psi on stocka. I've seen people run 18psi.

Also what power you reckon an extend ported 13b with that turbo on 12psi with standard 550cc injectors upgraded fuel pump, front mount, 3inch exhaust and microtech? Oh and running on 2 stroke premix.

Cheers,

 

You need secondary injectors upgraded if you want to go over 12+

After xx amount of boost, 12psi+ on stock s5 turbo is just pushing hot air. It's no point, I mean these turbo's boost drop after 6k.

Are you sure those people are not running a hybrid? It would be really retarded to run 18psi on the stock turbo.

Extend port? uhh what?

With power wise, I would guesstimate maybe 230-250hp.

 

This answers my questions too it seems.

 

well i didnt port the s5 turbo wastegate. With standard injectors standard turbo 3inch exhaust and front mount my 13b turbo made 280HP on 11PSI. So i was really happy with those results. http://www.youtube.com/watch?v=NZYKJ2dFpzU

 

Sounds good. You should post your dyno graph in the 2nd gen dyno section. You also neglected to mention you are running a microtech. You got some great tuners down under don't you!

 

Can s5 turbos actually make 280hp as easily as ganador makes it seem? i havnt heard of a s5 making that much power at 11 psi. I have heard of the bnr turbos making close numbers to that, but never a stock s5 turbo.

 

280 hp at 11 psi? I'm assuming that was calculated at the crank, and if so, what did you use for drivetrain loss? Have a dyno sheet? Cause if the stock S5 at 7.5 psi makes 200 hp, you made 40% more power with only 15% more air... quite the achievement and unless you're running about 13:1 AFR or leaner (on stock injectors, i wouldnt be surprised if you were very lean) which will heat up quite a bit and shorten engine life, or you're running water or alky injection, it sounds rather incredible. Especially considering that, with the wastegate fully closed, boost on the stock turbo approaching redline drops pretty quickly down to 8 psi or so which will limit max power numbers unless its a very cold day. On the dyno, even with a very large fan like that, your intake temps must be getting pretty toasty too, do you have IAT measurements to go with your AFR?

 

well on my s4 i taken off my manifold and knocked out that flapper door and welded the little hole shut so theres no resistance of that door with air flow. its starts to boost around 3,4k. from a dead stop. i hated that stipid actuator thing so i got rid of it. i couldnt tell if it was working or not since i bought the car with it not hooked up.

 

sounds like u got an aggesive streetport job too...good run

 

well... Its standard injectors, standard turbo running 11Psi, A/F reading is rich, power was measured at the wheels as you could see from video clip. There is no water injection or anything special.

http://s155.photobucket.com/albums/s288/Mendez_86/

 

Pretty impressive. I noticed the date on the graph is from 1998? I think the way it works is that they measure the HP at the rear wheels and calculate how much it is at the crank. Then you can add in the drivetrain loss and that would be your ultimate number. Either way it will still be very good. Props.

 

What? Are you saying you don't have a wastegate at all?

 

No, I'm sure he means for s4. They have the twin scroll from a wastegate.

 

I think he is saying he removed the twin scroll on his S4 manifold. Common mod.