hustler

iTrader: (6)

how lean should I go to spool this ******? Anyone want to make a dummy AFR table from like 2k-4krpm from 100-220kpa?

Dyno tuning 2.0 is next weekend.

hustler

iTrader: (6)

I swapped 6-speeds and discovered something shocking...a gasket was choking the exhaust down to roughly 2.5". So I hollowed it out with the dremel and holy ****! Its making 15psi at 3700rpm and AFR is all over the place now...it won't event idle right anymore. I have new gear ratios so I can't really tell if its faster or not, but fairly obvious.

Time to go back to the dyno.

Laur3ns

Who the hell put that gasket in? Is it the one that connets the CAT to the DP? Good to hear your spool is acceptable now. Makes me think of going to mount a larger turbo next time, if this one ever blows up. Not that Im unhappy with the power, but less heat and more headroom is FTW when you give up very little in spool. Mine makes 15psi at around 3300rpm, but I should be making less power @15psi cuz I flow less.

Just rethinking that you have a better head (on your engine that is..) to maybe that turbo would still be too large for me. One night of MLV should get your AFRs back in shape - if you have a decent target table. Then redyno for spark to see if you can get more out of this setup. It should be making less heat now with less backpressure, thus allow more timing.

hustler

iTrader: (6)

Either I put the gasket in or a friend helping that day.

I have to tune fuel today for a track event in a few weeks. I think I can get the turbo spooling faster, and can definitely get more power...but its overboosting again.

As for more spark...I can't get any more output because I'm at MBT in every cell at max boost.

Laur3ns

Your cheap cure to overboost is buy a 14psi can from BEGI and throw away all EBC and MBC. The expensive route is a fancy EBC, not the one from MS but a working closed loop product.

ZX-Tex

iTrader: (15)

I want to hear some lap times after that track day Hustler. Where are you headed?

I am having the same happy spooling with the 2871. There is a bit of lag with it compared to the 2560, but it is really not that bad. It just means I have to shift a little later, no big deal. The rush when the turbo spools is sweetness.

Hustler I am also having mild overboosting problems. When I tune the EBC, just a tad bit of extra duty cycle on the wastegate at the pre-target boost RPM cell (like only 10% more) will send it into 2-3 psi of overboost. It is weird too, because it is not overshoot that goes away, but it holds the overboost to redline, even with 0% EBC.

I have the wastegate actuator arm about a turn or two tighter than where it would be with it just slipping onto the wastegate arm. I thought I might loosen it a bit and see if that helps.

hustler

iTrader: (6)

I have the 14psi can and a cheap MBC. Unfortunately I think the real fix is going to be EWG. As long as the boost stays under 19psi, I don't care. However, I may need to run this car on wastegate at the track because its somewhat violent on the street at full throttle.

hustler

iTrader: (6)

My first track event is TDR@MSR...hopefully it makes it through at least one session because this is also my shake-down.

I have the same overboost problem...I think our wastegate ports are too small. We need EWGs.

If I end up with turbo/manifold hardware problems and loose bolts, then I'm calling BEGi to do a V-Band job with one of stainless steel tial turbine housings on my car with an EWG.

Braineack

iTrader: (62)

If your EBC is at 0%DC and you're still making to much boost, thats the lowest boost you can make at redline. So increase the boost in all the RPM ranges before that point and youll have no more overboost :P But yes, the wastegate is too small.

you can play with the valve PWM rate Hz, might be able to get finer tuning out of it.

ZX-Tex

iTrader: (15)

The thing is, if I back off slightly on the EBC, or do not use it at all, it is OK to redline, no overboost. I am only using the EBC (open-loop) to get it spooled, then going to 0% DC just shy of target boost and letting it run on the wastegate.

Laur3ns

I run WG only street and track and prefer that. With EBC or MBC boost comes in more violently and Im having corner exit wheelspin already in higher gears if I stomp it. Plus my drivetrain may live longer like this. Mine would overboost with this can + mbc also, I think the egay mbc just doesnt vent quickly enough.

Laur3ns

Fixed for ya. A 14psi can + any boost control makes for happy overboosting if you want to settle around 14psi. A 7psi can + BC will do better but will spool a tad later and may have boost drop off at high rpm. The world sucks.

Laur3ns

So you go to 0%DC at around 4000-4500rpm I assume? And that doesnt because your overboosting will also happen in that area?

ZX-Tex

iTrader: (15)

I have to go to 0% DC before that. Right now I have 100% DC at 3000, and go to about 10-15% IIRC at 3500 (at 4000 it is at 0%). I am not backing off at 3500 because I am making peak boost, but because if I go to say 30% DC at 3500 then it will overboost somewhere north of 4000 or so.

OK Hustler, if you can beat my best time at MSR of 1:23.X (1.7m course, CCW, on my SV650 race bike) I'll be itchin to get my car out there, bad.

hustler

iTrader: (6)

i like the way the MBC comes on. EBC was ok in my old FWD cars, not in the track toy.

ZX-Tex

iTrader: (15)

I forget, are you running a MS? If so, you can use throttle position multipliers in the open-loop DC table. Works great, makes the power come on smoother as the throttle is slowly opened.

Adaptronic has something similar. There is an option that takes the DC% and multiplies it by the throttle position %. Effectively the same thing.