Boost PSI @ Highway speed ?

[2strokesmoke]

Hi guys,
While I have owned many 1.6D's - this is my first Turbo diesel
I have a question about boost PSI at highway speed (65 MPH)
I'm running 9 PSI @ 65 MPH on Level ground,no wind,just myself in the car(no cargo)
The car is an 88 Fox GL wagon,which I purchased from someone on the Vortex over a year ago.
It has a 1.6TD conversion-engine & trans from an 85 Quantum (T3 turbo,NO intercooler,2" ID exhaust
with cherry bomb muffler)
I estimate the car weight to be around 2000 lbs to 2200 lbs
Door sticker says GVWR 3050 lbs
Does 9 PSI at a steady speed of 65 MPH on level ground seem right ?
Pressure reading is taken from a "T" fitting-which is in the hose going from intake elbow to IP
How much PSI are you guys running?
I've also noticed- at idle I read -2 or -3 (vacuum) with a clean air filter
I have double checked my gauge(snapon mechanical gauge) which is accurate and does rest at "0" with engine off
Thanks for your input
Mike

[bbob203]

Depending on the gearing that should be about right. With wastegate turbos you can't really change the cruising boost level unless you set max boost lower.

[8v-of-fury!]

If you had a turbo with a later style waste gate on it, you could apply vacuum to one side to open the waste gate fully while cruising.

Not that it really matters anyway.

[745 turbogreasel]

So many variables...
My car runs  7-12 on flat ground at 70 by changing only how hard rain is falling.

[CRSMP5]

if thats the quantium turbo... seems high to me..

quantiums i think were bigger then the mk1/mk2 of the era.. and mine runs abt 3psi at 65 on level ground in my b3... vs the tdi pea shooter of 12-15psi pn my kubvan..

but what engine rpm you abouit? tranny choice may be your issue..

fyi vanagons had a quantium style turbo but was smaller... so again turbo info helps.. over the pond..

[2strokesmoke]

Hi Guys,
Thanks for your input !
I gather my 9PSI is about right then.
I don't have a Tach,so I don't know what RPM is.
I'm guessing it low.
Prior owner installed a trans with a tall 5th gear
I don't remember what car it came out of, just that it was from an audi.
Is it normal to have -2 to -3 (vacuum) at idle and just above idle ? (new air filter)
Thanks,  Mike

[fatmobile]

Do you have an EGT gauge?
 What does that read?

[libbydiesel]

Vac depends a little on the gauge and what your elevation is.  At 10,000 ft. of elevation with a cheapo gauge, sure.  Assuming your gauge is working correctly and your location (Long Island, New York - sea level) is accurate, then no, you should not see any vacuum.

[2strokesmoke]

Thankyou for the replies.
I don't have an EGT
Yes gauge is accurate
You are correct- I'm at sea level
What would cause vacuum at idle & just above idle ?
I have a new airfilter.
Intake manifold is clean,intake boot or hose is good, no leaks
Can Cam timing effect this ?
Thanks,Mike

[745 turbogreasel]

oil soaked filter?

[2strokesmoke]

Air filter is clean-no oil
But thankyou

[libbydiesel]

Intake restriction. 

[2strokesmoke]

The Intake manifold,elbow,turbo,intake boot(from turbo to airfilter box),air filter,ect..are all clean and no obstructions anywhere.
I've also noticed that the Vac/Boost gauge ocassionaly flutters at idle (maybe 25% of the time)leading me to believe there is a bad intake valve (With Properly adjusted valves-mechanical head)
The reason I asked if incorrect cam timing will cause vacuum at idle & just above Idle(sometimes up tp 1500+ RPM with no load)
Is this:
I have suspected that my crankshaft TDC mark is incorrect (odd as it sounds)
I bought this car with engine & trans already installed- I finished the 1.6TD conversion
Prior owner stated that flywheel and clutch were from the same 85 Quantum 1.6TD
I timed the engine using correct IP lock pin & Cam Lock Plate I have used many times before & set IP to 1.05.
Tripple checked everything,like I always do.
Engine started instantly,was smokey,Had NO power at all and barely rattled at all (very quiet)
So I reinstalled dial indicator,double checked IP timing & cam timing- All the same @ 1.05
When I registered the car a few months later and took it for a drive- I could barely reach 50 MPH and tons of fuel smoke.

Finally I threw out the specs and advanced the IP timing by ear. ( I had to advance it a LOT to make it sound right.)
The engine still starts instantly and runs good,but is Smokey (fuel smoke) and really doesn't make any power until boost.
I also have the -2 to -3 Vacuum at idle and vacuum will reach -5 to -6 at around 1500 RPM (No load)
I've never seen this before.
I've been driving the car this way,for about a year and have turned the fuel down as low as I can & still have fuel smoke (any lower and I won't reach 55 MPH)
Is there any way of determining TDC without removing the head or oil Pan ?
Does this make sense to anyone ?
Thanks,Mike

[8v-of-fury!]

Is there any way of determining TDC without removing the head or oil Pan ?
Does this make sense to anyone ?
Thanks,Mike

There was a post in a thread about this last week, can't find it though.

[libbydiesel]

Is there any way of determining TDC without removing the head or oil Pan ?
Does this make sense to anyone ?
Thanks,Mike

http://www.vwdiesel.net/forum/index.php?topic=34145.0