Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   DIY Turbo Discussion (https://www.miataturbo.net/diy-turbo-discussion-14/)
-   -   There's the BOOST! (https://www.miataturbo.net/diy-turbo-discussion-14/theres-boost-5680/)

samnavy 11-18-2006 05:15 PM

There's the BOOST!
 
All right, I hooked up one of the DSM wastegate actuators I had (the one I'd polished of course) and installed it. It's running with the MBC inline but with the spring completely backed out (shouldn't be doing anything).

WOW!!! is one way to put it. It feels great. Running the old busted actuator off just it's spring tension was a waste of time. THIS is how baby spools!
I'm seeing what I believe to be standard T25 spool response:
She starts to make noise at about 1500rpms
0"hg at 2k,
1psi per every 150-200rpms, seeing 6-7psi by 3000rpms
and a full 9psi by about 3300-3400
and that's at only about 75% throttle.

I can't give it more because the clutch will break loose during acceleration... and slips a little anyways in the higher gears above 7psi. Only seeing a max of about 6psi in first gear though. Again, all of this is with no MBC help.

Pics are of old actuator on workbench and new one installed. I had to bend the arm a little to get it to line up with the stock hole. I also had to drill and tap new bolt holes on the backside of the compressor housing.
Not a bad hours work!

You can see a little oil on the CHRA, that's from when I took the oil line off, it's not leaking.

Braineack 11-18-2006 05:20 PM

sweet!!!! glad you finally got it running.


here is my latest wideband log:

11.3psi, 305c injectors, OEM AFM
http://www.rev2red.com/images/cars/11psi_305cc.jpg

F20turbo 11-18-2006 05:21 PM

that looks really nice in there. Thats about the spoolup I would expect from a T25...nice and linear and super responsive. You can have full boost at just about any rpm.

F20turbo 11-18-2006 05:22 PM


Originally Posted by braineack (Post 57871)
sweet!!!! glad you finally got it running.


here is my latest wideband log:

11.3psi, 305c injectors, OEM AFM
http://www.rev2red.com/images/cars/11psi_305cc.jpg

and you are using the OEM AFM to keep it a little more lean up top am i correct in that assumption? That plot looks really good actually, I bet 11psi feels pretty nice on that S60;)

jayc72 11-18-2006 05:37 PM

What smoothing factor are you using on your graphs?

Mechazawa 11-18-2006 05:53 PM

Sounds like you and I have the same turbo eh. I made flanges for the Nissan intake housing, but that DSM one looks like a good trick. Must be cheep too.

Braineack 11-18-2006 06:05 PM


Originally Posted by jayc72 (Post 57876)
What smoothing factor are you using on your graphs?


none.

Yeah Andy I was just tinkering around, I'm acutally trying to get rid of the rich top end, using the OEM AFM acutally helped keep it leaner a tad longer. The car idled right up with the 305s, just had to turn the Idle Mixture Screw (had to drill the cap off) back one full rotation.

Sam, looks like it's time for a clutch. Glag it was just a wastegate and not something like a bad rebuild ;)

UofACATS 11-18-2006 06:55 PM

Sweet! That's some nice spoolin' action as well.

samnavy 11-18-2006 07:01 PM


Originally Posted by braineack (Post 57884)
Sam, looks like it's time for a clutch. Glad it was just a wastegate and not something like a bad rebuild ;)

I lost sleep over the past few nights thinking about that possibility.

Looks like I'll do my initial testing with the 305's after all.

I've got the weekend after Thanksgiving weekend set aside for the clutch job.

Brain, you also said something about the idle mixture screw... proof I still don't know everything. Where is it and (if it wasn't obvious) what does it do?

Braineack 11-18-2006 07:10 PM

http://members.aol.com/solomiata/af_mtr1.jpg

There is a capped bung over the screw, you have to drill it out. I've never tried messing with it before but i was able to idle the 305s with the OEM AFM with it. Initial AFR at idle was 11.5:1. One turn counter-cockwise got it to a steady 14.7:1 AFR. Works in the same fashion as the idle control screw on the Throttle Body.

UofACATS 11-18-2006 07:32 PM

Damnn this guy's good

F20turbo 11-18-2006 08:20 PM

see there is a way to use a stock ecu and actually make a decent fuel curve;)

Ben 11-18-2006 11:05 PM


Originally Posted by braineack (Post 57888)
One turn counter-cockwise got it to a steady 14.7:1 AFR.

Are you still runing the vortech fmu? Since I pulled the vortech and replaced it with the BEGi FMU, I idle at 15.7. It idled at 14.7 with the vortech. If I add the smallest amount of throttle possible, it richens up to 14.7 and holds 14.7-15 as no load revs increase. Untouched stock afm and idle mix. Stock NGK heat range 6 gapped at .035. Totally smooth ~825 rpm idle. I thought that was interesting...

Then again, I still don't totally trust my lc-1. It may displaying correct afrs, but it can not reliably translate readings into voltages. I'll know more when I get to the dyno Monday.

Braineack, when you're viewing your log in LogWorks2, go into the "Channels" tab and scroll down to "Smooth Channel" and see where it's set. It looks to me like you have 1.5 or 2 seconds of smoothing.


Ben

4sfed5 11-18-2006 11:08 PM

Holy crap!

12.7:1 AFR at 11 psi?????? what are youre egt's doing???must be like 2000*F!!:eek5:

samnavy 11-18-2006 11:41 PM


Originally Posted by 4sfed5 (Post 57904)
Holy crap!
12.7:1 AFR at 11 psi?????? what are youre egt's doing???must be like 2000*F!!:eek5:

Would that be good or bad? What's normal?

Braineack 11-18-2006 11:44 PM

no smoothing is selected.

idling at 15 is fine, less gas wasted

wouldn't egts be more dependent of timing? i pull to 6*.

i don't have an egt gauge, but 1400-1600 is normal.

F20turbo 11-19-2006 12:29 AM


Originally Posted by 4sfed5 (Post 57904)
Holy crap!

12.7:1 AFR at 11 psi?????? what are youre egt's doing???must be like 2000*F!!:eek5:

Thats not really all that lean, I run around those same AFR's under full boost up to 4500rpm. Torque peak on my engine is at 5000 or so and by that time im around 11:1 afr's. I have been running 2000F egts for 4 1/2 years without any knock on pumpgas and anywhere from 8psi-14psi.;)

Just so you know like Brain said EGT's are more dependant on timing than anything else. I retard 4* of timing total from the stock IGN curve. And like I said 12psi on pumpgas my setup never knocks, I mean never. I know what knock sounds like and I dont get any...if i did I would know it or my engine wouldnt be in one piece anymore. EGT's at lower rpms where we are a little lean is ok since the only time EGT's are going to get real hot is under sustained high rpm conditions...and thats where I am super rich along with Brainboy.

Braineack 11-19-2006 01:54 AM

I experience no knock as well, and that's the engine killer.


All times are GMT -4. The time now is 05:18 PM.


© 2024 MH Sub I, LLC dba Internet Brands