The build is as follows:



Bottom End

- Stock Y7 block no guard or anything

- 75mm Vitara Pistons

- Scat H-beam Rods

- ACL Race Bearings All-Around

- OEM Y7 Oil pump Ported and Shimmed

- D16Z6 Crankshaft



Head

- Refreshed Y8 Head

- BC Springs and Retainers

- Comp Cams 105300 Cam

- Y8 VMS Variable Cam Gear

- ARP Head studs

- Nippon Racing MLS Headgasket



Turbo Setup

- MaxSpeedingRods "GT3076R"

- SPA Turbo Cast Top Mount Manifold

- CX Racing Intercooler Kit

- Treadstone TR11 Intercooler

- Turbo Smart 38mm Wastegate

- MAC 3 Port Boost Solenoid

- 3" Downpipe Out the passenger Bumper with wastegate tied in



Fuel

- Walboro 255lph pump

- K&N Fuel Filter

- AEM on Rail Fuel Pressure Regulator

- Fuel Injector Clinic 775cc Injector

- Shell 93 Octane



Misc

- BKR7E plugs Gapped to .022

- Stock Old Distributor and Plug Wires

- Rotella T6 15w-40 and K&N Filter

- P28 ECU With s300 v3



As soon as the car got on the dyno it threw a code 9 (No. 1 cylinder position (CYP sensor). Tuner said it was a common problem with running OBD2 Distributors on OBD1 ecu's but, the car hasn't thrown the code in months of daily driving the car. He bypassed the code and the car ran fine with no misses. Once he got to doing power pulls he said the car wasn't responding to more boost/timing and that something was holding the car up. Seemed like it could be cam timing so they double-checked and everything seemed good. Adjusting the cam gear only made less power. After a while of trying to figure it out, we had nothing and came to the conclusion that the setup just wasn't efficient and just won't make the power. Even then they thought it should make more than that at that boost level and said that the manifold is choking it up and the china turbo just isn't efficient enough.



From my understanding, these setups are making closer to 300whp at that boost level. I was wondering if anyone had some insight on what might be causing this issue. Any Ideas are would be greatly appreciated!



The dyno is a 4-hour drive so I want to make sure I actually fix the issue before I waste a whole weekend going back.



Pictures of the setup as it was at the dyno and dyno sheet:

 

What psi is this graph at? Did you check for boost leaks?

This looks like an extremely laggy setup.

I would throw a log manifold and a 18g turbo and have a ton more fun.

 

This is at 16psi and yea the turbo is a little big for the little single-cam. Since its a bigger turbo the 16psi of boost should mean more power than a smaller turbo. The goal for the car is to put it on e85 and go for 350-400whp so a log manifold will only hurt that.

 

Yea id say the turbo is worn. 16psi on that size should be making a lot more power. Or you have a big leak somewhere

 

Yea I'm gonna do a boost leak test soon and they pulled the screen off the turbo and felt it and it checked out so hopefully its a leak. But, the map is in the manifold so 16psi is making it to the manifold so maybe its leaking out the injectors or IM gasket.

 

It could still be bleeding off a lot of air.

 

Yea maybe but considering it builds boost and holds it without much shaft play or smoke I don't think the turbo is messed up.

 

What compression motor?

 

Stock bore Vitara pistons which are usually 8.4:1, but he has cylinder head work done so that might alter the compression a little bit.
I’m estimating 235whp isn’t too bad for a D16 since they produce like 110whp stock, but this one is lower compression, so that’s at least 125whp from 16psi of boost on a turbo known to be less efficient than a Garrett, somewhat inefficient intercooler, and unknown efficiency of the exhaust manifold.
It is making boost late in the RPMs though, and that’s strange it wasn’t responding to more boost. Is it tuned too rich of fuel?

 

Your distributor timing appears to be retarded... and in my personal experience, I have seen MULTIPLE cars with VMS adjustable cam gears that ran like total ****. Try re-installing the OE cam gear and set your distributor timing. If the engine runs differently, especially if the engine feels more "snappy"... you may have found it.

 

Are you running on a stock map sensor? Might need a 2bar..

 

Zeal shows ~7.8:1 compression on this setup (Vitara / stock length rods) - oof. It's definitely going to be laggy, but I would think it should be making more power than 235 whp on pump 93. Any idea how much timing is in the maps at 16 psi?

 

Co-sign with a vengeance. Even a log manifold with a GTX2871R would do just as good. Better turbo match, even if the leaks were fixed.