Lots of upgrades, but still no power.

[Chuck Leeper]

the intake to upper plenum seal blew out for about the 100th time.

Let me guess....At the ft, behind the t/body?

 

[TURBO2]

Let me guess....At the ft, behind the t/body?

Yes, there and the back passenger side.
I wish I had the knowledge back then when I first bought it to test it for vacuum leaks and have had GM replace it all under warranty.

 

[GNVYUS 1]

Couple options...

Confirm plenum bolts are tight and no one inserted longer ones and it slightly bottoms out. I got my intake back all messed with and didn't notice until I sold it.

Take your plenum off and have it measured, maybe it's that casting. This then can be milled flat again or just buy the aftermarket one and measure that. From here you'll have an idea if it's your intake too but at least you'll have 50% of the issue covered etc.

Regardless, maybe a double gasket would help with any casting that's off and keep you tight.

 

[TURBO2]

Couple options...

Confirm plenum bolts are tight and no one inserted longer ones and it slightly bottoms out. I got my intake back all messed with and didn't notice until I sold it.

Take your plenum off and have it measured, maybe it's that casting. This then can be milled flat again or just buy the aftermarket one and measure that. From here you'll have an idea if it's your intake too but at least you'll have 50% of the issue covered etc.

Regardless, maybe a double gasket would help with any casting that's off and keep you tight.

I even tried a Remflex seal and tried everything from stock torque to Remflex's instruction to tighten to 50% squish, to bolts about to break. I even tried the Remflex seal with RTV, always the same result of vacuum leaks followed by no boost. The intake has to be not even close to being machined right. I even measured out new bolts that were not long enough to bottom out. This has been an ongoing nightmare for 38 years.
I've gone through the original upper plenum- not machined true from the factory.
Stock TB leaking
Kenne Bell upper plenum not only not true, but somehow like someone twisted it front to back
Kenne Bell TB leaking after only about 1,000 miles
AccuFab Upper plenum and TB unfortunately looking like exact duplicates of the Kenne Bell ones. Plenum not true (not as bad as the Kenne Bell one though)
TB leaking after about 2,000 miles.
At this point I may have to park it until next spring, rip out the intake, and weld the plenum to the intake so it never can leak again. But then I run the chance of going down the rabbit hole of the bottom side of the intake being just as bad and never sealing ever again. Very, very frustrating.

 

[GNVYUS 1]

Ouch you've done a lot...

I hear ya on just stopping a constant issue that's just winning after so many attempts, $ and time. Someone could weld the intake to plenum (my Champion is also 2 piece so that's not worth it) and that'll stop the leak, just make sure to add the power plate or whatever IAT etc things to it and then that problems solved. Hahaha

You might wanna step away, have a good turbo or resto shop pull the intake, plenum, measure and machine both etc and just not deal with this anymore. Losing another year of driving vs $1000 might not be good since there's only so many total years to drive these.

 

[TURBO2]

Ouch you've done a lot...

I hear ya on just stopping a constant issue that's just winning after so many attempts, $ and time. Someone could weld the intake to plenum (my Champion is also 2 piece so that's not worth it) and that'll stop the leak, just make sure to add the power plate or whatever IAT etc things to it and then that problems solved. Hahaha

You might wanna step away, have a good turbo or resto shop pull the intake, plenum, measure and machine both etc and just not deal with this anymore. Losing another year of driving vs $1000 might not be good since there's only so many total years to drive these.

Yeah, I could have Brian Cotton take a look at it. I just didn't really want yet another giant bill. I've never had another vehicle do crap like this before. Most other stuff that I've used right stuff on before, I don't want to have to take it apart because I usually would need a hammer and prybar on it. This though, just will not stay sealed.

 

[GNVYUS 1]

GN = Giant Note

It could be worse, wait until you hear what it costs to change oil on a Ferrari and that's just the oil, brakes are a new cars value. LOL

 

[ITSAV6]

VP Octanium. 2 quarts in a full tank of 93 is 101 octane. 20psi and 18 degrees on my car. I also have a 2800 stall and a TE61 0 boost 2800rpm launch

 

[ITSAV6]

 

[ITSAV6]

My timing is rather aggressive @wot not under boost but this is what works for my combo

 

[THensley]

2 8X10 picture frame glass
4 sheets of 220 wet dry sand paper
1 can W-D 40
1 old dish towel
and 30 minutes I could have the intake and doghouse flat and true.
This can be gone with the intake bolted in place.
your making the intake gasket blowing look like a mountain when its just a mole hill.
OK back on track
as mentioned 93 and 20 lb is in the danger zone and adding enough fuel removing timing to stay away from KR will result in less than tire destroying power that is longed for.

 

[ITSAV6]

As suggested turn boost down to 17ish Do you have a quick spool manual boost controller(like the RJC one)? What is the timing #s on the 100kpa line on the timing map?

 

[TURBO2]

As suggested turn boost down to 17ish Do you have a quick spool manual boost controller(like the RJC one)? What is the timing #s on the 100kpa line on the timing map?

No, I have an aftermarket boost solenoid controlled by the ecuGN.
Timing is 16 at 800 rpm rising to 22.6 at 7,000 rpm.

 

[THensley]

that a odd timing table
my TT chip idles 27* ,(39* at 1700 at 40 mph) at (60 mph 1900rpm cruse 40*) at WFO 23.5* 1-2 gear, 2-3 gear 21*
You need to take a closer look at your timing tables Im not furniture with ECUGN but Holley timing table is not linear
post a pic of your base timing table the big square graph with all the funny colors
Im going to need to down load some software to look at your fills on my windows computer I'm a MAC person with just windows for my power logger

 

[TURBO2]

that a odd timing table
my TT chip idles 27* ,(39* at 1700 at 40 mph) at (60 mph 1900rpm cruse 40*) at WFO 23.5* 1-2 gear, 2-3 gear 21*
You need to take a closer look at your timing tables Im not furniture with ECUGN but Holley timing table is not linear
post a pic of your base timing table the big square graph with all the funny colors
Im going to need to down load some software to look at your fills on my windows computer I'm a MAC person with just windows for my power logger

 

[Chuck Leeper]

What I'm seeing.. I'm a Holley guy, excuse any mis info...
Appears that the boost is in psi. Most prefer KPA....
The boost axis is a choppy rise to 43psi. Way too many big jumps. If you don't run boost that high, re-organizing the scale helps prevent big jumps in timing.
Appears that the rpm resolution could be written down to 700 to say 6000.
Again that will add reference points and smooth the table.

 

[THensley]

^^^
I see the same thing
Chuck likes KPA Im a PSI person I believe more and more have switch to KPA but work with what you understand best.
Did your ECU come with an Eric M tune?
If your running a 3 BAR Map no need to exceed 30 PSI
Most Buicks no need to Buzz them over 6000

 

[Turbo1dr]

Isn't 16 inches of vacuum at idle a little low for stock internals?

 

[TURBO2]

^^^
I see the same thing
Chuck likes KPA Im a PSI person I believe more and more have switch to KPA but work with what you understand best.
Did your ECU come with an Eric M tune?
If your running a 3 BAR Map no need to exceed 30 PSI
Most Buicks no need to Buzz them over 6000

Yes, Eric set up the initial tune.
ecuGN has a built in 4 BAR MAP.

 

[TURBO2]

Isn't 16 inches of vacuum at idle a little low for stock internals?

I'd have to let some of the tuners chime in on that.