Hi Guys,

I want to get a better understanding of the twin solenoid setup and how people use/tune for it!

On the X only one of the solenoids is TBEC corrected, the other is passive.

I had a thought that instead of implementing both an Active AND Passive altmap BDEL/BWGDC I would just do the Active.

Thoughts?

Cheers
David

 

David - I set the same boost (WGDC#) setting for both but merely use the secondary (grey plug on the solenoid) to control boost with Apexi BCS.

I guess doing both would be better suited for most setups runing twin solenoids as one.

Regards
Sohail.

 

well i have a feel most people will just set 1 solenoid to 100% and then control boost by adjusting the other solenoid.

does 50% on the Active solenoid and 100% on the Passive solenoid produce the SAME boost as Active=100%, Passive=50%

 

I am not sure, but I think the passive solenoid is not modified by the error correction tables at all. Active =100% and passive = 50% should produce the same results until upward correction is needed.

 

I don't know anyone using 2 solenoids to be honest, everyone here uses 1 after-market bcs.

They produce different boost as below. All I know that secondary produces more boost from my testing.

Dr John Banks can confirm although he has moved onto GTRs!!!

 

Oracle I never tested as I always used EBC, but there were earlier threads on here or MLR where you did and the colours of the plugs and which channel they were was discussed.

If you just altmap the active, then it should have enough control bandwidth to be useful I think.

 

I found in Evo X that one solenoid controls the boost when you start and race the car, you change gears at high rpm and the other controls boost when you accelerate big gear from very low rpm. So this way you can control both overboost and boost while racing and the second for not overboosting when you accelerate from low rpm and high loads.

 

From my tinkering with a JDM Evo8MR, what I have seen is that setting solenoid 1 @ 100% and solenoid 2 @ say 50% doesn't produce the same boost as setting solenoid 2 @100% and solenoid 1 @ 50%.

I dont know if it has to do with the pills inline before the solenoids...meaning that one before solenoid 1 is bigger than the one before solenoid 2 or vise versa....

BTW Tephra, very very happy to see you working on these roms.
Please PM me details as to where to make a contribution.

 

^ So how do you tune _your_ WGDC maps? Do you just set 1 to 100%?

 

^^ as i am sure u know.. from the factory the duty on solenoid 1 is maxed out at 100% and solenoid 2 has up to 40% used.

I have just ordered a Grimmspeed 3 port solenoid which i plan to use to replace the primary solenoid (one that is set to 100%) and use this to control boost primarily. I may just reduce the duty on the 2nd solenoid to 0%, or set the secondary solenoid to 100% and just add duty cycle to the grimmspeed as needed. I would stick to which ever method would provide a more stable and smooth boost curve.... If anyone knows of a better way which utilizes the 2nd solenoid please do share...

I was told by Mrfred that the 2nd solenoid is a dummy solenoid, i.e. the ecu has no control over it, so it was used to increase the boost from the stock GSR 19psi to the MR 21psi....

Honestly my problem with this set up is that the engine loads (i cannot log boost) are not very smooth, they display some bumps which would correlate to a bumpy boost curve. I am hoping that the grimmspeed unit helps to smoothen out these bumps...

Tephra I would like you to keep the functionality of the 2nd solenoid as it does provide some extra headroom if more boost is required.

 

If your going with a 3port then yes the 2nd solenoid will become pointless.

when MrFreds says "dummy" he means its not subjected to TBEC, you can still dial in a WGDC% and the ECU will do that %, but not adjust it according to TBEC (like sol #1)

The main goal of my thread is to find out whether we can get away with JUST making an altmap of solenoid #1 WGDC maps, and leave #2 as is...

If people that are using the twin-bcs setup can post their WGDC maps for both solenoids that would be great

 

If by this you mean that the alt map would pull the settings for solenoid 2 from the main map then by all means I agree, as it seems the best way to use the 2nd solenoid will be to set it to 100% and add boost with the 1st solenoid....

Waiting eagerly on the Tephra V7 version of 96260009

 

Well since no one is really telling me anything I guess I will go ahead with my original plan:

For twin solenoid equipped cars (9626000X, 88580007):

- leave the passive solenoid as non-altmappable
- make the active solenoid as altmappable:

This will mean:
- If you have a 3port, you will be fine, since you replace the active bcs with the 3port
- If you use the stock twin setup, you will have to keep the passive solenoid @ 100% (or whatever) and control boost using the active solenoid

 

I think thats the best option i dont really know of any tuned evo's that stick with the twin solenoid setup its usuallly ditched in favour of a ebc or 3 port

 

Dave if that is the same as the v5.10, I think wastegate duty's were combined then that is fine.

Twin solenoids - been years since mapped one like this, definetly a thing of the past

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