Jason,

I was wondering if you did any more fine tuning with your SBC-Spec R EBC. I did some repositioning on mine and removed about a foot of hose from each connection, and now my turbo spools way too fast and spikes. I had a bear of a time with the settings on my drive up from LA this weekend. Since we discussed it so much previously, I was wondering if your settings had changed any from the initial ones we had figured on from before.

I noticed, after reducing the hose length, that the turbo spooled up a LOT faster and I didn't have to put my settings up higher than 30 to achieve 1.10hkpa with a gain of 19. Last night, when I was doing some spot checking with my settings, with cooler air, I spiked for a split second up to 1.25hkpa TWICE. I reduced the settings to 20 and the gain to 15, and am now driving very conservatively until I can find a good optimal setting. Hopefully you have some ideas, since you spent a lot more time fine tuning than I did.

Any help you can give is appreciated.

shadowcat

 

Did somebody else mistake for again

 

yeah yeah

I'll pm

shadowcat

 

the reason it spike is becase normally on a stock turbo and stock wastegate/actuator , you don't want to run anything over 10 on the gain...

I found that gain of 7 worked the best with stock turbo..

Tommy
www.mpjperformance.com

 

Tommy,

Thanks for the input. It's odd, but before I chopped the hoses, I needed a gain of at least 17 to get the turbo to spool fast and properly. With the shortened hoses, I find it spiking more. You suggest a gain of 7? How fast is the spool? What about the boost settings?

shadowcat

 

Every turbo tends to react slightly different, but I have setup a few SBCs and they all seem to follow the same settings.

From what I remember, shorting the hoses increased spool time because you have less hose area to cover/push. With a 7 gain, it spooled a bit slower than if you would run a 20 gain, but virtually no spiking.

As for the spooling characteristics, it spools up really fast, it was too fast for me because it sucked for commuting, I was constanly hitting full boost (16.5 to 17) on a slight incline.

I think I was running a 55 to 58 set.... depending on the weather...

Tommy
www.mpjperformance.com

 

hmm.. okay, time to experiment again. I'll start with a gain of 8 and a setting of 50 and work from there.

Thanks, Tommy.

And if Jason ever sees this thread and/or my PM, he can chime in

shadowcat

 

Hey have you untuned boost controller guys seen this?

http://forums.nasioc.com/forums/show...hreadid=529496

Hopefully you have EGT gauges on #4.

 

Yep, I run a gain of about 7. And 46,47,48,49 for each for % and a limit of 107 (15.5psi). My Blitz solenoid is where the stock solenoid was and I get no spiking. For street driving I almost never hit 107 - yer not going to see more than 103 not matter how much you turn the boost up in lower gears (with a mild, bolton setup, ayhow). In 3rd I sit nicely at 106-108. Only on the freeway and hitting it hard to I get spike over the limiter to maybe 109.

jason

 

Actually, I found the problem. I had a broken vacuum tube coupler on one of the solenoid to turbo connectors. I had to replace the 1/4 to 3/16th coupler and the soft tube coupler since it tore. No wonder my boost was inconsistent. I changed everything. Thanks for the tweaked settings. I'm fixing everything again and redoing my settings, now that I have a sealed system again.

shadowcat

 

You know what, I just checked and I'm actually running a gain of 18. Heh

jason

 

wow gain of 18? i am running 59 set and 7 gain. 4th gear pull on freeway spiked me upto 16.5psi... i wonder what would it spike to at gain of 18~ :banana:

 

Yeah i think i'm running my % too low.... 49 is my highest. I'm gonna go crank up the % again and lower the gain... I miss my topend

jason

 

well, at one point, I was running a gain of 19, and a set of 50, but that was to compensate for the long hoses. When I cut them down, for a while I was running a gain of 18 and set of 49. FAST spool, controlled max spike to 1.10, average 1.00-1.03 running hkpa. I'm currently running gain 10, set of 53. Fast spool, max 1.10, average 1.01-.103 running hkpa, with a more controlled spike.

I'm playing with my settings again.

shadowcat