Hopefully, I chose the right sub-forum. If not, please move it

2000 TransAm... 6.0 with an 80mm turbo and a 4L80e...

So, after 3 years of not being able to accurately tune (to car's boost/hp potential) fuel or spark via HPTuners...
I finally got myself a Terminator X Max.
My hope is to use the Holley for engine and transmission tuning, and retain factory ecu for gauges, fuel pump, etc...

I also have a recently installed BOOST LEASH boost controller, that I haven't even dialed in yet...(X Max kinda fell into my lap)

My original plan was to use the Boost Leash for boost control, but realize it may be a little silly to not use the Holley instead.

I don't want to run Co2, and have been reading multiple threads on here for hours.
Some say use a single 3 port MAC valve,
Some say use a 4 port,
Some say use a dual 3 port...
Then some say use a dome pressure sensor, and some say use the MAP voltage...

I have dual 44mm wastegates which, with 4# springs, with a Turbosmart EBoost Street and single 4 port could make 4# to 22.5# of boost.

Dual gates now each have 10# springs, which (while testing) easily made 25# with Boost Leash and their dual solenoids/valves.

Now for a question, or 3, lol.

Trying to keep this whole Holley/Factory ecu setup as "simple" as I can, so wondering what the latest consensus is for Holley controlled boost control??
...again, no desire for Co2 or onboard air, and I would likely have MAC valve(s) turned OFF (for 10psi boost) for just cruising around

So, and I know this has been beaten to death, but just looking for latest thoughts on controlling boost from 10psi to 28psi or less?

3 port, 4 port?
splice into MAP, or dome sensor?
or keep Boost Leash?

Thanks in advance.
.

 

I run 39psi of boost using twin turbos.
On WG springs alone boost is 18psi.
I run dual 38mm EMUSA WG's


My Eboost2 was rock solid only varying less than +/- 0.5psi through a 32psi run.

I now use the Megasquirt Pro to control boost but it's not dialed in that good yet and it varies a tad over +/- 1.0psi at 39psi. I'm not real happy with this so may go back to the eboost2 if it doesn't get better.

I use 1/4" diameter tubing for all the WG tubing which runs approx 8ft long by the time the tubing is all routed. Too small of tubing can't exhaust the domes through the solenoid fast enough so I make the tubing large.

I use one 3-port solenoid and no brass muffler on the outlet port of the solenoid.

ks

 

Thanks for the reply Kevin. I also use 1/4" tubing.

What do you use for the boost reference sensing? Do you use MAP, dome pressure, or something else?

 

The Eboost reads psi at a vacuum block under the hood via 1/8" tubing.

The MSPro reads the 4-bar sensor located under back seat.

ks

 

Gotcha. Yeah, my old Eboost Street had a line directly to the controller, but the Boost Leash has its own MAP sensor, in my case, under the dash.

I think, unless I hear good reason not to, that I'll reference off of my 3 bar MAP sensor on the intake, and try a 3 and/or 4 port MAC valve. Thanks for getting back to me.

 

I think what it mostly comes down to is making sure everything is plumbed and setup correctly. I prefer to keep things as simple as possible with plumbing and wiring. I also want the WG springs to supply as much boost as possible then add some dome pressure for a little additional boost.

On my car I was planning on boosting to 45psi if needed and had made spacers to shim the WG springs to give me 28psi on springs alone but never needed them b/c all I needed to reach 950hp goal was 39psi. With 18psi springs I was able to get to 39psi boost thus my goal. Once the new head/cam combo gets together boost should only be around 28psi to hit 1000hp.

I think the boost fluctuation with the MSPro is mostly from the tubing/plumbing so I plan to redo all that before going into the MSPro and play with settings.

ks

 

Badass!
I'm just a baby boost LS car, lol.
I have 10# springs, hoping for a high of 25-28.

With my old Turbosmart Eboost Street, I could make a max of 22.5 with 4# springs and 4 port mac valve. I guess it simply couldn't make anymore as it was. The Boost Leash has made 25 on a street test blast.

No idea of my RWHP but 19.5 made enough to go my best of 9.32@147 with a 4160# race weight. I'm wanting an 8.9999999 before I retire this old girl. Lol

 

My car is heavy at 3700 with me and all I want is a solid 150mph+. The car isn't set up for launching hard so foot baking with 60's in the 1.5's are fine (and easy on parts) but I want to to steamroll out the back door. I had planned to hit the track this fall until the head gasket went on the 950hp dyno pull two weeks ago so now I'm selling all the 2V induction and swapping to 4V heads and new turbos..

ks

 

T

That's my other goal as well, 150mph. I did hit 148.98 last time to track, but 150 just didn't happen...
So close, yet so far, lol

 

I have a four port with a very lite spring 3-5 psi. did the "domeMAP" this for a while. It was spiking some before it would hit the target. So I have it in open loop just commanding a duty cycle. It has eliminated the spike and now I have a slight rising boost curve.

One of these days I am going to put a map on the dome. I have been told it would be easier to dial in

 

Many like the dome, but it adds complexity. Matt from Sloppy has a mod using the map to go closed loop map based, or you can use open loop nitrous control as well. The 3 port works well if you don't have a ton of drive pressure, and you're happy with roughly double your gate pressure. If you have high drive pressures, or want a larger boost range, then the 4 port works better. The 4 port is a little more sensitive to pwm changes so does take a little more time to tune imo.

 

V4? Want to share!?

 

Meant v2, and I was wrong. I thought they added map, but I must be thinking of the Sloppy mod.

 

V3 is in testing. Devin showed his laptop and it had the icon. I didn't watch it but I heard Holley put it on Mike F.'s car. Devin said it had some of what people asked for. I am hoping for map based boost control.

 

Thanks for the replies so far guys. I appreciate it!

 

Just update...

Went with a 4 port MAC and open loop PWM - boost control.

Works great and is smooth and consistent so far.

With 10# springs in both gates, it made 15psi at 35% duty cycle. 19psi at 40%, and scramble added exactly 5psi as I asked it to.

I also realized that the MAP splice I made is not even needed with the open loop PWM setup, lol.

My hope is that with my 1 open input and 1 open output, that I can somehow use the V3's traction control with the wheel speed sensors I already have.

 

BTW, if anyone has any idea how the Holley traction control strategy works, and/or how I wire it...I am all ears, lol.