NB2 vvt vics AVO gt2560 17psi - 264hp 253tq
 

Car:
02 NB2
94 block, VVT head, Vics manifold
stock (8.8?) pistons w/new rings
eBay rods w/arp bolts
ACL Race bearings stock size
AVO Cast manifold, 2560 Turbo w/billet compressor wheel (from S14 silvia)
2.5" downpipe, 3" catless exhaust, MT bigass magnaflow muffler.
MS3, FF640 injectors
93 octane gas.

today's best pull: 264 whp and 253 wtq at ~17 psi

Dyno run and timing map attached. (dont mind the super rich AFR, my MS3 was showing a solid 11.3-11.5 under boost. must be the dyno tailpipe sniffer). or my wideband. donno which one is not correct.)

What you guys think? any more power left in this snail? or maybe more timing?
https://cimg0.ibsrv.net/gimg/www.mia...ff6184f51a.jpg
https://cimg2.ibsrv.net/gimg/www.mia...a008f19076.jpg

https://cimg2.ibsrv.net/gimg/www.mia...1a42d89d1a.jpg

I would consider that to be very strong.

Looks good. It would spool a bit better with modern hotside parts, but nothing to fret about. Timing map could use a bit more work too

It probably doesn't need more timing in my opinion.

I'd call it strong also, given the old-school parts.

Dann

yeah not more, just smoother transitions

according to compressor maps on line, you have 5psi to go before you are off the larger efficiency island. So, yeah, more in the turbo.

Crank it to 22psi see what happens.

lol, no. At 22psi you're just overspeeding the turbo. The gains are minimal beyond 18psi on a 2560R. 30whp more power at this boost level is max shaft RPM for the turbo. There's proably 15-20whp in the intake manifold, all above 5500rpm, but there's nothing left in additional boost here.

Linky to example?

Huh. I'd have expected a bit more with the billet wheel.

You're not running EBC, right? The additional spool should make things way more fun.

2560r on a decent cast manifold with a normal 2.5" downpipe is ancient by todays standards? pls explain
Any pointers on the timing map would be greatly appreciated.

old school meaning not EFR or the cast manifold?

I dont think this turbo has much more left in it, i had to do some trickery to have it at least stay some what flat and hold 17ish psi to redline, if i set the solenoid all to the same number, boost would start at 17.5 and end at 15psi by redline.

here is the open loop table i had to run.
https://cimg6.ibsrv.net/gimg/www.mia...cd72dc1e1c.jpg


most of what i read says 2560r is capable of about 300hp, so i was hoping for about 280-290ish. but i guess not.

Running open loop for now, i tried closed loop, but it would oscilate by 2psi up and down, so still learning how to make closed loop work.

i think spool is decent, 200tq at 3250rpm is inline with most other 2560r dynos i see posted here. but i am sure closed loop will speed up spool and transient response.

actually I didn't look at the plot close enough. saw peak torque around 4 hence that post. you're right, 200tq at 3200 is actually good, real good. the mani and dp on the avo kits had some serious cheater bends if I'm not mistaken.

I wouldn't push it further either, there are like a handful of miata's that hit 300 on a 2560, and all of them were pushed to the absolute limit. 22psi is way too much, ignore Marcello's post, you're totally fine.

timing map: why do you have a dip around idle? no need for that, if the car cant' idle steady without it, you've some idle tuning to do. also cruise cells can use 1-2*, and then you got the timing pretty aggressive from 100kpa-160kpa, but then it plumets 5* at 180. I don't really see why.

Thanks for the reply,

The 12* at 1k rpm and 15* below, my tuner did that, he said the 15* will help catch the rpms if they dip too low. the tuner actually had 10* instead of 12*. i upped it to 12 while trying to combat a strange stalling problem i am having when coming to a stop with the clutch depressed. im still having this once is a while stalling.

ill interpolate 160-180-200, i think this will bring the numbers closer together. also set idle at 10*

better?
https://cimg9.ibsrv.net/gimg/www.mia...c7ad09638a.jpg

I will give this map a try later tonight, see how it idles and boosts in 180kpa area

AVO manifolds are actually pretty nice, cyl 2-3-4 points right at the turbo, only cyl 1 far away.
https://cimg0.ibsrv.net/gimg/www.mia...6f6af26458.jpg

Ive seen the squared off Avo downpipes, i dont think i have one of those, mine looks like a normal 2.5" DP

https://cimg9.ibsrv.net/gimg/www.mia...d325ff3f0a.jpg

Yes and Yes.
Pretty solid overall, and congrats on the numbers.

Is there a reason why you open the wastegate at 2000 rpm?
You should keep it closed until your target, which with the 2560r should hit 17 by 3400-3500 rpm, I bet your spool would be way better like that.

Thanks for the input, much appreciated.
took it out for a drive, seems to idle fine, time will tell.

playing with closed loop this weekend, following your megathread, but currently my head is in information overload. so much info in the EBC thread.

I dont think any boost is happening before 2k rpm, 2-3 psi maybe? so the wategate is closed by the spring anyhow.

Now I've seen the pics your manifold and downpipe look alright.

Dann

My goal is to hit these #s on the mk setup. :)

Just by opening the wastegate you limit boost.
I suggest you look up Greg's video about boost control.

i think you have a backwards understanding of boost control.
the ZERO number in that table below 2000rpm represent a fully open boost control solenoid, and at 2000rpm i am calling the solenoid to CLOSE to the value of 48 to start increasing boost.

for example, if that table had ALL zeroes in it, in every cell, then its basically not having boost control active and running off the wastegate mechanical spring.
The higher the number, the less air goes to the wastegate, the more boost you build.

and in open loop boost control, you cannot hold the wastegate shut until boost target, only closed loop does this, which i am currently experimenting with.

Enjoy your car as it is then. Not going to argue with you.