Ha, Looks like I'll be ordering the GM unit soon... also helps to explain some of my fluctuations at the 50% boost range.

....now to devise a way to keep that GM clicker quiet! ...this may sound silly but I'm thinking the cloth and rubber inserts that hold the top of the toiled to the bottom might be a great idea

... I should stick one behind the mount for my LICP also now that I'm thinking about it!

 

Rubber isolation should take care of the noise issue because the solenoid is not loud. Its just that the sound is being amplified by the chassis when there is no isolation.

 

mrfred, I dont have the MAC to compare with, so your probably right about it being a 35 instead of a 36. Also, I do run the AEM solenoid with an inline resistor (10ohm) and my duty is in the low 70's to see 25psi on an otherwise stock Evo IX. It's certainly capable of making more boost, although it does seem to be very touchy. In fact I run almost a flat 72 duty cycle accross the entire rpm range except for the higher rpm range when I get up to around 80. Even slight variance in the duty resulted in very choppy boost. The good news was I already had the solenoid as it was included in my truboost gauge and I've gotten good results from it. I've tuned cars with the GM 3port as well and it works great. Next time I'll probably go that route but the AEM was in my toolbox and I got it to work well. If you have one already you may as well use it. If your in the market to buy one, the GM is better and cheaper.

Did you do your testing with the muffler on or off? I've removed the AEM's muffler and vent back to the intake.

 

the couple cars i have tuned i always recirculate it back into the intake.

 

Some pictures on the AEM website definitely show a MAC 36A solenoid, so it seems that AEM uses both types. Anyhow, I was looking at the MAC 35A flow diagram yesterday, and realized that I had tested it in the wrong configuration. I'm going to do a retest on Friday in the correct configuration. I had been using the muffler, but it has no effect on flow of the waste air. The other solenoids I have been testing with the waste port venting to ATM as well, so its an even comparison.

 

Were you testing it set up for an external, or an internal gate, mrfred?

 

I just always wondered if that cork looking muffler was a restriction.

 

The intent was to test for internal wastegate setup, but I mixed up the two ports with nipples on them. I'll get new pressure data on Friday and put everything together in a nice plot over the weekend.

 

First post now includes new, detailed test data. Final result is that the GM still wins.

 

Great thread. I was planning on selling that AEM solenoid with the TruBoost that I have once I get it back. This just cements my decision a little more. lol.

 

Great test mrfred.
It will be great if anyone can send you the Ingersoll and the MAC 36A.

I have a question :
Is really possible to use a 30Hz signal for the BCS with the stock ECU?
I have done a search on the forum,maybe this is a in-development feature?

 

I think one thing that comes out of the testing is that the highest flow solenoids also appear to cause the largest pressure fluctuations. Seems that the ideal solenoid is a balance between flow and pressure fluctuations. Now that I've tested the 35A in the correct configuration, my feeling is that the 36A will perform similarly. I wouldn't mind testing the Ingersoll Rand though.

Yep, 30 Hz can be done. tephra may include it in his next ROM patch, or I may do a standalone patch. Still need to discuss with him.

 

yeah I am still ironing out the details on that one.

I have been running 2x50 loops (instead of 1x48 stock) for a while now, and no downsides.

We can run more smaller loops, or less bigger loops. obviously the tradeoff is exposing yourself to more deadtime of the solenoid - which results in less real wgdc.

 

Very interesting thread. I think I will have to add a GM BCS to my wish list ;-)
Thank you mfred for this great work.

 

well I was really hoping to see something showing the MAC 36A is great but it looks like I'm going to have to buy the GM BCS.