So I finally got my car properly tuned after a year of running the MS on it. I took the car to a local tuning shop called UMS Tuning and those guys are the ****. The car is much faster, but it definitely still needs some tweaking.

It is having some serious boost drop off, which is hopefully due to the low psi waste gate actuator! Because of this we didn't run much timing and I will definitely be making a trip back there soon. Thoughts?






(link to same photos)
http://imgur.com/xpPNc&gyjG5

 

Congrats. I'd say it still has at least another 20hp in it easily, and fixing the boost issue/smoothing out everything should result in a much more pretty looking curve. Looks peaky as hell as is.

 

boost isn't dropping off, wastegate is spiking

 

is the wga adjustable?

 

Post your spark map if you don't mind. You also need a 3inch exhaust to free up some more power.

 

Yah I was just stoked that it didnt blow up ha. The actuator is a non adjustable, whatever came with the begi kit. Possibly a 6psi unit? The shop recommended going with a 10psi actuator.

 

What all does your setup consist of (sorry can't see sigs if you have it listed there).
injector size?
if you have the injectors/fmic/other supporting mods for it, just slap an mbc on there and see if that will smooth it out. they're like 15 bux. if not then its new wga time.

 

My current setup is 1.8l, Gt2554, Flyin Miata IC, Megasquirt, 440s, Cat-less Enthuza 2.5', begi s downpipe and manifold. I actually have some fancy turbo xs dual adjustable boost controller. This is the best boost that we could get with it. My goal is a smoother curve and to hit 200whp.

I'm going to try an 8psi actuator and hope that its strong enough to hold..

Heres my spark map:


Do you guys think that a better flowing manifold and down pipe would make a huge difference on this setup/turbo?

 

From what I've read/heard TurboXs is a "bleed type" mbc and is junk. No personal experience with one, but I'd try a known good ball/spring one like a hallman es or the nxs ones many of us are using.

as for gains from less restrictive exhaust: yes the gains should be pretty decent.

I'd focus on your boost issue for now, and try to get more power out of the setup as is. You should be well in the 200-220whp range even with the 2.5 exhaust

*edit: doens't look like your spark map is too conservative either

 

That was my SR20 t25 which is very close to a gt2554 on a begi s1 kit at 9psi. Running Megasquirt with 440cc injectors on a stock 94 block. The only big difference between what you have and I had are the different downpipes and I have a 3" Enthuza exhaust. Below is my final tuned spark map.

 

Yeah the turbo xs one that I have is the bleed type, and it is my first experience with one. I can give a different type of boost controller a try, I had better luck with a 5$ home depot brass special ha. (Although external wastegate setup on completely different car). It wouldn't hurt to give a halman or something a try. Surprisingly the dude who tuned it was stoked on the turboxs unit though.

Yeah the spark map on mine doesn't seem very conservative at all. I'll have to get the boost issue sorted and then go back to the dyno.

Shuiend, that looks like some nice power for that setup. Thanks for posting your spark map! What kind of dyno is that on?

Would a 10psi waste gate actuator be proper for this setup?

 

Feed that turbo a LOT of timing up top. The compressor is tapped out by ~5500 or so so you can run a huge amount of timing and prop the torque curve up with it.

My '99 GT2554R spark map - please don't just copy it, but look at the numbers and see where you can turn it up a bit on your next trip to the dyno.

 

Where's the boost source for the waste gate? If it's from the compressor, block it off and source the boost from right before the throttle body. Don't waste time on a MBC or new wastegate before you do that.

 

FWIW I made 221whp with a GT2554R on a 1994 1.8 and only used a 2.5" exhaust with the Begi seperated gasses DP.

 

+1
If this isn't done yet, it def should be THE FIRST thing you do. Free "mod" ftw