nicknack

Got the SR22VET tuned today with the .92 IWG 7670. It was doing 300kw at 15psi. Ended with 408kw at 26psi tapering to 23psi (intentionally). 300kw at the wheel at 4.5k and revving to 8.5k is going to be fun.

Got my new SR22VET running with the T4 .92 IWG 7670. Not noticing a whole lot of response loss compared to the old 2.2L setup with the T4 7163. Granted this new motor is built a lot nicer and has properly done +2mm exh valves which I guess helps. Seeing it hit my 10psi boost cut at about 2.6k with no preload or wastegate duty and a 12psi spring, I'd expect it should do 20-25psi around 3.5k. it starts pulling hard at around 2.5k and is very linear. The 7163 did 23psi just before 3.5k. Tune booked in for the end of the month so will have some proper results EOM.

I never had issues with boost control on my T4 IWG 7163. Boost was always easy to control, but the tuner and I went for a creeping boost curve to give a nice powerband. This is a 9.5:1 compression sr20vet (still 2L) by the way. Intake cam was advanced 4 cam degrees and the exhaust retarded 1 or 2. I will go again for a retune with +2 intake and - 1 exhaust which should bump power up a bit. I'll also fab up a 3.5" down/front pipe. This dyno reads pretty low compared to most in Sydney. Slight dip in the power curve was because of a slight misfire. It made a few extra KW in a later pull (346kw) but i'm pretty happy with how it drives considering it makes this much power. The tuner was just so impressed and said this was way ahead of a normal sr22det with a gt3076r he tuned.

Checked the flex join in my downpipe today and the internal braid is fine and 3" diameter. The only other potential restriction in the exhaust would be my mid-muffler which has offset in and out. I checked the turbine when the exhaust was off and it looks perfect.

Cam gears are advanced 2 degrees on the intake and retarded 1 degree on the exhaust. I guess that doesn't help with overlap, but we figured it'd be a pretty safe bet to widen the powerband a bit. I think I will change cams but undecided on which ones to go. I'll look into it more

Stock p11 cams have a fair bit of overlap so I guess that lowers dynamic compression and doesn't help make power. I'll try pull the exhaust off tomorrow and check it out. I guess if I can remove a restriction from it I'll see boost rise a bit higher due to less back pressure since I run open loop boost control.

My build thread is here http://nissanroadracing.com/showthread.php?t=5350 Block; - s15 block - 87mm CP 9:1 VE pistons (making around 9.5:1 compression with thinner HG) - Spool imports rods (aussie company) - stock crank, ACL bearings, ARP mains, Cometic 1mm HG Head; - p11 SR20ve head with stock cams - new guides and seals - BC springs - a bit of porting and polising (cleaning up casting marks etc) - p12 cam solenoid Other stuff; - Borg Warner EFR 7163 t4 twin scroll with a TS full race manifold - Mazworx v2 intake manifold (original one cracked everywhere and was replaced) - Bosch 2200cc injectors, Turbosmart FPR1200 FPR, Walbro 450LPH e85 pump - Adaptronic plugin ECU and Race tech dash 3 - Ls2 truck coils - Z32 gearbox with a NPC ceramic button clutch - will hold 600WHP but feels very very nice to drive - 4.36 diffdiffdiffdiff I have a flex join in the downpipe so if there's a restriction, I'd say that's it. My offset mid muffler seems too far back to cause that much back pressure, but I'm gonna cut that out anyway

Boost was done like that intentionally. We didn't end up filling in the midrange with boost due to it leaning out. I've had it hold 10psi till redline with the medium canister.

I've been following this thread for a few months. I got my Sr20vet tuned with a twin scroll 7163 the other day. It drives really really well and as expected transient response is amazing. Im not convinced that 300kw at that boost is accurate though judging by other results with the turbo. It started leaning out up to so we couldn't push it much further. It took about 90% wastegate duty to hold that boost up top and the tuner thinks there was a lot of back pressure, so I wouldn't be surprised if the flex join in my downpipe has started falling apart. Ive got a TURBOSMART IWG 75 with a 23psi spring in there so I would've thought it'd be able to hold boost with less effort. The reason boost tapers up is because we started adding more at the top to see what it would take but didn't end up working backwards and increasing boost lower down The other thing which might be happening is the bov opening I guess. The signal line for it is quite long and subject to intercooler pressure drop so I wonder if that affects it. Its a stupidly nice curve though with effectively 4000rpm power band so I'm super happy with that. I'm just not sure if that 300kw is really the turbos potential or if there's a setup (like an exhaust restriction) or dyno factor bringing it Down.