New DP, low boost

[Shimy87]

Hole is un touched....no pre turbo leaks anymore.....im convinced Steve is correct and the alchy is drownding out combustion and not letting it build enough heat/boost. If I dont hear back from Julio today tomorrow I will lower initial and see what effect I get

[reality]

Are the vacuum hoses plumbed properly? Restricter in place? Tuner style with stock wastegate rod? What are you measuring boost with?  Just throwing out ideas.

[Steve Wood]

I have seen a couple of cars do this with Julio's system...that is why I suggested cutting back on the initial flow rate after reading Julio's instructions.. .

There are so many possibilities. ..With a HD actuator, one should get about 18 psi with an 1/8" tension on the rod...wiring it should give close to 30 psi if one were dumb enuf to find out.

The only other idea I have is to put the factory dp back on and see what happens....As much as I hate working on cars, I would not be too interested in doing that LOL

[reality]

When in open loop I always tune for the most boost/timing with the supplementary injection system turned off, and then start adding it in along with more timing and boost.

If tuning in closed loop you can set your target AFR (or AFR curve - ie. richer at MBT, leaner at the top end), then massage the boost and timing curves to suit, while cranking up the alky or whatever.

In my Buick it was propane on around 18psi and alky in at 25psi, and ran it out to 30psi.

 I can see a FEW people[engineers] cringing at this.

[Steve Wood]

I have seen a couple of cars do this with Julio's system...that is why I suggested cutting back on the initial flow rate after reading Julio's instructions.. .

There are so many possibilities. ..With a HD actuator, one should get about 18 psi with an 1/8" tension on the rod...wiring it should give close to 30 psi if one were dumb enuf to find out.

The only other idea I have is to put the factory dp back on and see what happens....As much as I hate working on cars, I would not be too interested in doing that LOL

There is one thorn in all m y hypotheses, he was apparently making more boost, rich, or not, before he swapped the downpipe.....

[reality]

Well there are different downpipes for different turbo"s so if they arn't matched then that would create problems.

[Steve Wood]

I don't recall if you unbolted the downpipe and pulled it away from the the turbo, or not.  But, if the puck is not sealing, you should see carbon streaks emanating from the wastegate hole around the puck sealing area.

[Scoobum]

Ported on the left...untouch ed on the right. Shimy...did you buy that turbo new...or used?

[Shimy87]

Bought it new, looks like the one on the right and the dp puck is about an inch and a half round. Did some tweaking on the puck before and I think it is sealing well. Some background, with stock dp to achieve 24 lbs boost I had the boost controller maxed out. And had to take almost all adjustment available with the chip to lean it down to run well. I believe I was Alky heavy before also, but now with that issue and adding the free flow of the new dp and now it can't get to 24 lbs???  My hope is the less restrictive pipe is just making this "rich alky" issue become a larger issue. We will see. Thanks for all the input guys!!!!

[Scoobum]

You THINK the puck is sealing well?

[Steve Wood]

Check it....look for carbon tracks. I have been fooled many times

[Steve Wood]

Should run leaner

[Shimy87]

There were no carbon tracks when I checked it before. I will pull it and put a thin layer of grease on it and tap it a few times and confirm its sealing. I will post some pics.

I thought the free flowing dp would help my rich issue. it's always something with this dang car

[reality]

put the y hose back on That should raise the boost 4 pounds and try it. I used to run tuner style back when but wouldn't now.


Are you running an alky chip? If not try running with the alky turned off. If you want to run alky with a non alky chip you might have to play with the fuel pressure- eg  lower it .
Course if you are running an alky chip well forget that.




Another thought are you running a volt booster of any kind.

[1 RARE T]

If it was drowning with too much alky, it would bog and not pull/make power. Your alky tank should be running out really fast if this is the case. How much does it use after a couple pulls?


Carbon tracks would'nt show up with just a few WOT runs. Takes a while.


Waste-gate actuators can be funny. I've had some that needed to be tighter than you would think to get them to work at the desired setting.


Years ago, the trick was borrow the wifes' lipstick and coat the puck with that. You should see a EVEN mark around the hole. Not off centre. Being careful not to smudge during re-installation of the downpipe.


Either it's not sealing properly or the waste-gate is weak where it's set and lifting slightly allowing boost to bleed off.