924Board.org

[MikeDanger]

went for a spin around the block last night, after finally examining the exahust manifold area. looks like the weld on the downpipe flange has a huge crack that is atleast 180* around it. (since I had been wondering why i'd see a puff of smoke on cold start up in that area)
Wondering what effect it might have, since its after the turbo?

Now, I hooked up a vac/press gauge (the testing kind, not "in dash")
I plugged it into the vac line comming from the TB. Also I had to use 10mm hose however. So im wondering how accurate of a reading i was getting?

I didnt go to redline, since I was on some back streets with a 35mph limit (and the police dept a couple st over!) but about 5k+ and was seeing about 5lbs of boost.

It pulled ok enough.... I guess... but seemed like it could have a bit sooner spool.

(maybe im just not used to it since my DD is a V

It was about 38 degrees out.
Id like to see how it does at 10 or 12psi, but it seems like it would take forever to build that boost.

It has a mostly stock exhaust, except that the muffler has been replaced, and an additional resonator seems to have been installed, also the rear section of tubing has NON mandrel bends with some noticable compression.

any feedback here?
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It was either this or a giant box of legos

[924-76]

You should reach max boost between 3500-4000 RPM, 10 psi in my case

What is your vacuum reading at idle?
as reference: http://www.924board.org/viewtopic.php?t=40048&highlight=rpm+boost
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1976 924 N/A ROW SOLD
1980 931S
1981 931 Part car RIP

[MikeDanger]

vacuum seemed low (as in not much) at idle, but I didnt pay close attention, I just know the needle was not much below 0 at idle.

It was hard to hold the gauge and drive/shift (at night) But I did see noticible vacuum, when I would floor the pedal from low rpm while rolling.

But again i'm not sure how accurate the reading is VS. pulling the reading from the WG line.
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It was either this or a giant box of legos

[MikeDanger]

I do have a cone filter inplace of the air box.

How much do you hear the turbo when driving? I could hear it quite loudly, much like when you hear a diesel spool, in wondering if the crack made it louder at all, or is the spool usually quite audible?
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It was either this or a giant box of legos

[924-76]

Low vacuum and low boost, sounds like a vacuum/boost leak.
_________________
1976 924 N/A ROW SOLD
1980 931S
1981 931 Part car RIP