IHADAV8.com - Turbo Buick Tech, and Nonsense

Tech Area => General Buick Tech => Topic started by: larrym on May 15 2016, 02:37:35 PM

Title: Boost/rpm flutter
Post by: larrym on May 15 2016, 02:37:35 PM
So what would cause this? It is not as noticeable 1-2 and it feels fine not really noticeable while driving but sure it's slowing me down. This is in 3rd gear my external gate need a rebuild?
Title: Re: Boost/rpm flutter
Post by: Scoobum on May 15 2016, 02:59:09 PM
How are your head gaskets?
Title: Re: Boost/rpm flutter
Post by: larrym on May 15 2016, 03:03:02 PM
good I hope no knock oils clean new last summer

Title: Re: Boost/rpm flutter
Post by: larrym on May 15 2016, 03:05:19 PM
blue is boost the orange is user fuel trim 
Title: Re: Boost/rpm flutter
Post by: Steve Wood on May 15 2016, 03:12:49 PM
You give us no scale..how much variation is the flutter that you see?
Title: Boost/rpm flutter
Post by: larrym on May 15 2016, 03:19:20 PM
Sorry 2 psi max and about 65 rpm on the spikes
Title: Re: Boost/rpm flutter
Post by: Scoobum on May 15 2016, 03:38:27 PM
I did a search on the other board. Patrick Rubio...who's forgotten more about turbos than I'll ever learn had a post recommending to check for exhaust leaks at the headers, crossover pipe...and the three bolt flange. Other culprits can be head gasket(s), vacuum leaks, turbo getting weak, wastegate issue or intake gasket leaking.

I always seem to take a beating cuz I use exhaust gaskets, turbo gasket and new studs and nuts on the crossover...an d take my time tightening them evenly.
Title: Boost/rpm flutter
Post by: larrym on May 15 2016, 03:53:39 PM
These are old KB headers with Vband clamps on the crossover I will put the stethoscope on and give it a good once over see what I can find. I run gaskets too never have to much problem with them.
Title: Boost/rpm flutter
Post by: larrym on May 15 2016, 05:14:41 PM
I'm going seal this up see if it helps......
Title: Boost/rpm flutter
Post by: larrym on May 18 2016, 02:37:24 PM
Found another leak....
Down pipe to turbo at the bottom right at the waste gate port ordered a remflex gasket to see if that will seal it up the cooper RTV was a no go and I really don't want to get the down pipe and exhaust housing surfaced that means pulling the housing off the turbo.
Title: Re: Boost/rpm flutter
Post by: good2win22 on May 18 2016, 04:15:51 PM
Found another leak....
Down pipe to turbo at the bottom right at the waste gate port ordered a remflex gasket to see if that will seal it up the cooper RTV was a no go and I really don't want to get the down pipe and exhaust housing surfaced that means pulling the housing off the turbo.
I thought it was pretty common to see a leak at that point on the down pipe and turbine exhaust housing.  You could wrap some sand paper over a file and then run the file over the turbine housing to get an idea of how bad the surface is.  I don't think folks worry too much about post turbo exhaust leaks anyways.
Title: Re: Boost/rpm flutter
Post by: larrym on May 18 2016, 05:12:11 PM
With the external gate after the leak I'm thinking this could be cause of my boost fluctuation which seems to affect RPM in 3rd .
On the street it pulls great and with digital boost gauge I can see it fluctuate from 23 to 24 PSI.
The turbine protrudes outside the exhaust housing, its an F1 65mm turbine plus I would have to pull the studs I use to attach the down pipe to hand lap the housing.



My thoughts were if I could get the boost pressure at a soild number I would be better off running it out in 3rd at the track maybe pick up a half a tenth  :P 
Title: Boost/rpm flutter
Post by: larrym on May 22 2016, 03:12:43 AM
Well the 2 exhaust leaks are fixed with no real difference except an increase in max boost went from 23/24 to 24/25
There are no obvious vacuum leaks. My buddy suggested a new set of plugs and inspect the wires. If that has no affect I have 2 extra coils I will swap out and see if one of the six I have is the culprit.
Title: Boost/rpm flutter
Post by: larrym on May 22 2016, 02:30:06 PM
Just so I'm correct in my thinking if I disconnect both vacuum lines To the gate I should be running on spring pressure in the gate alone say 15 psi?
If it climbs to 28 psi in the blink of an eye I have a problem......
Title: Re: Boost/rpm flutter
Post by: larrym on May 26 2016, 05:27:44 PM
next question  whats the best approach for hooking up a manual boost controller?
mine is set up as per figure 3.
Title: Re: Boost/rpm flutter
Post by: Scoobum on May 26 2016, 05:31:53 PM
Larry...if Steve doesn't have an answer for this one...hit up PACECARTA on the other board.
Title: Re: Boost/rpm flutter
Post by: Steve Wood on May 26 2016, 07:39:25 PM
It's been many years since I ran dual wastegates on the cross over  :D

My opinion is that the more sophisticated that we make these cars, the more flaky they become.  I think Paul would be a good place to get an opinion as well.
Title: Re: Boost/rpm flutter
Post by: good2win22 on May 26 2016, 10:03:30 PM
Would one cylinder with a random misfire cause this?  Plug wires? Weak valve spring?
Title: Boost/rpm flutter
Post by: larrym on May 29 2016, 09:55:05 PM
It's possible I have a new set of plugs gaped and ready to go in.
Title: Boost/rpm flutter
Post by: larrym on May 30 2016, 01:16:04 AM
I didn't get the plugs in had pick up the daughter and I hate burning myself:) after I dropped her off I went out and did a little test hit. I have removed the shims from the waste gate so it's just the spring it's not fluttering. I rolled into it in 3rd it went to 24 held steady for a bit then 25 then 26 and I lifted no knock trying to decide what's better the flutter or the creep....
Title: Re: Boost/rpm flutter
Post by: Steve Wood on May 30 2016, 04:50:58 AM
Factory wastegate
Title: Boost/rpm flutter
Post by: larrym on May 30 2016, 10:03:20 AM
No it's a turbonetics evolution external gate this what I found when I inspected itI removed the5 shims and re adjusted the controller to get it back to 24 psi
http://photoshare.shaw.ca/image/a/4/f/119991/image-2.jpg?rev=0
Title: Re: Boost/rpm flutter
Post by: TexasT on May 30 2016, 10:29:57 AM
Well, I'm certainly no guru, but here is what I would try. It looks like there are several shims. Maybe try them half on one end of the spring and half on the other or some different combos more on one end and one on the other, if they fit in that way. Turn the spring over and do the shim shuffle that way.

You will be real good at pulling and installing the cover. Plus it is way easier than goofing with the 2004r governor and its springs.

Is there a replacement spring you can get that doesn't require the shims? Maybe do a little porting of the exhaust so it can exit easier. Nothing drastic, just a clean up.
Title: Re: Boost/rpm flutter
Post by: Steve Wood on May 30 2016, 10:47:23 AM
No it's a turbonetics evolution external gate this what I found when I inspected itI removed the5 shims and re adjusted the controller to get it back to 24 psi
http://photoshare.shaw.ca/image/a/4/f/119991/image-2.jpg?rev=0 (http://photoshare.shaw.ca/image/a/4/f/119991/image-2.jpg?rev=0)

No, I was suggesting a factory wastegate was the solution
Title: Boost/rpm flutter
Post by: larrym on May 30 2016, 11:10:16 AM
Ah I see that would mean a new down pipe. 😟
Title: Re: Boost/rpm flutter
Post by: Scoobum on May 30 2016, 06:24:04 PM
Keep at it Larry...you'll get it.  :rock:
Title: Re: Boost/rpm flutter
Post by: Scoobum on May 30 2016, 06:28:30 PM
Steve...the cost of a new RJC DP...shipping. ..30 percent exchange rate and tax...he wouldn't have coffee money left out of a thousand dollars.
Title: Re: Boost/rpm flutter
Post by: Steve Wood on May 30 2016, 08:24:23 PM
too bad there are so few Regals in the market...you could unretire and start manufacturing
Title: Boost/rpm flutter
Post by: larrym on May 30 2016, 09:52:03 PM
Steve...the cost of a new RJC DP...shipping. ..30 percent exchange rate and tax...he wouldn't have coffee money left out of a thousand dollars.

A guys gotta have money for Tim Hortons!
Title: Re: Boost/rpm flutter
Post by: Just a Six? on May 31 2016, 01:26:00 PM
It's a Damn Shame that something worth $500 US costs us almost double to have shipped up here. Even taking into account the weird shape & size it's about the same as I paid back when I was getting parts from the Buick catalogs back in the early 90's For us Toronto guys it's worth going across the border for a weekend or overnight trip with the wife & picking it up from the warehouse just across the bridge. I forget the name of the place? It saves a lot of $$ on shipping & taxes etc.
SimplePortal 2.3.7 © 2008-2025, SimplePortal