Just installed boost controller and gauge! - PeachParts Mercedes-Benz Forum

JEREMYC · #1 11-04-2006, 10:55 PM

Hello everyone! I just installed a Voodoo boost controler that I bought on ebay for like $7 along with a boost gauge a just picked up from Autozone for $39.99. I put the boost controller in line of the waste gate hose and the knob is easily accessible for me to tune the boost in. I lossened my far left drivers vent, pushed it back and mounted the boost gueage in the hole. The one I got from AZ had an aluminum bracket that I was able to bend out to hold the gauge in securely. That way, when/if I ever take it out, I can just reattach the vent and all is back to stock. I turned the boost controller to about half way to start out. Under normal acceleration the boost stays just under 10 psi. Cruising at 65 on the highway on a level area I am pushing 5-8 psi. Up a hill it may hit 10 psi. Here is my question. What should the boost be set at for factory specs or optimal specs. I am mainly interested in fuel economy and not performance but man did that controller make a world of difference. I also adjusted my rack bolt to get rid of the real bad engine shake. It helped a ton. I wanted to see how much boost I could "BRIEFLY" get and I got it to about 17-18 psi for about 2 seconds and let off. What are my safe limits here??? Thanks in advance for your reply!

sailor15015 · #2 11-04-2006, 10:59 PM

I've heard 11.5-13 are something like the stock numbers. Someone will chime in with the exact number. You don't want to go above those without increasing the fuel because all that will do is put more stress on the motor with no benefit. I've got a Dawes boost controller on mine. Its set at 13psi but it'll hit 14, maybe 15 if I floor it for a while up a long hill. Under normal full-throttle acceleration, however, it won't top 13psi.

Brian Carlton · #3 11-04-2006, 11:01 PM

It's not a question of "safe limits" but, the point at which additional boost does nothing but raise the temperature of the incoming charge air.

I've got the SD at 13.5" and, I'm quite convinced that there is insufficient fuel to use the air available at that pressure. I'm also fairly sure that the ALDA is maxed out at a level that's less than 13.5".

Therefore, I'd set the boost at approximately 12". Anything more than 12" is basically useless.

#4 11-04-2006, 11:06 PM

what was the stock pressure?

Brian Carlton · #5 11-04-2006, 11:09 PM

Quote:

Originally Posted by Tabor

what was the stock pressure?

Stock boost pressure on a 617 is 10.3-11.7 psig

JEREMYC · #6 11-04-2006, 11:09 PM

The controller I have is a cheapy but mechanically it works well. I do not have any type of markings to tell me where it is set at. So, I should be able to just back it out to where I will get the minimal amount of boost the the wore out wastegate will keep and just increase the controller until the gauge will not show anything greater than 12psi right? I guess anything over 12 psi at that point will just go on out the waste gate?

JEREMYC · #7 11-04-2006, 11:11 PM

Quote:

Originally Posted by Tabor

what was the stock pressure?

I did not check the stock boost before I installed the controller. I did the controller and the gauge at the same time and took it for a spin.

JEREMYC · #8 11-04-2006, 11:29 PM

Here are the picss:

http://i97.photobucket.com/albums/l231/JEREMYC_03/boostcontroller003.jpg

http://i97.photobucket.com/albums/l231/JEREMYC_03/boostcontroller001.jpg

http://i97.photobucket.com/albums/l231/JEREMYC_03/boostcontroller004.jpg

http://i97.photobucket.com/albums/l231/JEREMYC_03/boostcontroller005.jpg

Jadavis · #9 11-04-2006, 11:42 PM

Why do all of the boost gages I see have a vacuum range on them also?

I just picked up a 0-15 psi gage with the intention of installing it as a boost gage. Do I now have another useless spare gage?

-Jim

#10 11-04-2006, 11:59 PM

The vacuum gauges are just there because most of the customers they sell to have gas engines. 0-15psi is all you need.

sailor15015 · #11 11-04-2006, 11:59 PM

Quote:

Originally Posted by JEREMYC

I did not check the stock boost before I installed the controller. I did the controller and the gauge at the same time and took it for a spin.

If you would have checked it before installing the controller, you most likely would have been seeing around 7-8psi of boost, most likely due to age on the wastegate and being set slightly conservative from the factory.

Jeremy5848 · #12 11-05-2006, 12:26 AM

My waste gate is stock, as far as I know, and 'opens' at about 10.5 psi on my 0-15 psi gauge. I see about 2-3 psi at 60 MPH and about 6 at 80 MPH.

Jeremy5848 · #13 11-05-2006, 12:28 AM

Quote:

Originally Posted by JEREMYC

...That way, when/if I ever take it out, I can just reattach the vent and all is back to stock...

Excellent!

sailor15015 · #14 11-05-2006, 12:39 AM

Quote:

Originally Posted by Jeremy5848

My waste gate is stock, as far as I know, and 'opens' at about 10.5 psi on my 0-15 psi gauge. I see about 2-3 psi at 60 MPH and about 6 at 80 MPH.

Huh. Both mine were around 7-8 psi before adding the controller and I've read about several others that saw the same. Good to hear yours was still where its supposed to be!

#15 11-05-2006, 12:41 AM

Quote:

Originally Posted by Jeremy5848

I see about 2-3 psi at 60 MPH and about 6 at 80 MPH.

You should be seeing 6-7psi at 60 and about 10-12psi at 80mph.