Turbo

Idle should be around 17 to 18 inches of mercury. If you are not getting positive pressure it could be lack of air flow or maybe the turbo is too big. You will not get boost with no load, only under load can you get boost.

It goes to 0lbs of boost when it is under a load the turbo is pretty small

Maybe the carb is too small? Some of that piping is pretty rough. You need good flow on the intake AND exhaust.

How are you regulating the wastegate? If its hanging open youll have little to no boost. Your numbers are consistent with a NA engine

Wait a minute..... Your compressor inlet is going to the bottom of the carb and the outlet is going somewhere behind it? I see nothing nothing going to the carberutors inlet.... it has to be a sealed unit to make boost

You can draw through the carb which is simpler than trying to pressurize it. The piping is pretty scary.

I pressure tested the manifold pipes and there are no leaks

It does not look like it flows well.

It all runs through 1.5inch pipe u would think it would flow well

Ya I have a 4into 1 exhaust manifold

Go to 2" pipe.

2imch pipe on the manifold side or the compressor side to the intake

Would that cause it to go straight to 0lbs when I put it under a load

Zero is good. Minus 6 would be better. The lower the number, the higher the HP. I would try a bigger carb and bigger pipe from the carb to the turbo.

You cannot get zero inches of manifold pressure on a naturally aspirated engine. This means the turbo is working but not working like it should. I do not want to hurt your feelings but that piping job is probably your problem. You need smooth bends and bigger pipes. Bigger and smooth means more flow and more boost.

The 1 1/2" from the carb to the turbo is a bottle neck. I would go with 2 1/2".

Zero inches of mercury is atmosphere and happens when you open the throttle blade and get on it, there's no vacuum to be had while accelerating hard. Vacuum is only present when the throttle blade is restricting what the engine is technically capable of moving per volume hence the reason its high during deceleration. 22ish inches of (steady) mercury at idle is a sign of a healthy engine, if I had only 17 or 18 of be concerned. Take a drive with a vacuum gauge hooked up and find out for yourself.

What is mercury

Inches of mercury (In Hg). Mercury (Hg) as in the element. It's a common unit of measurment for negative pressure (vacuum) in the North American automotive world. Positive pressure (boost) is psi (pounds per square inch)

Ok so I have about 21 pounds of mercury at idle according to my boost gauge

One atmosphere is 29.92" of mercury (14.7 psi) which means that an air column that is all the way to the edge of space weighs the equivalent of 29'' of mercury. 0" of vacuum means the engine is pulling in as much as it can without pressurization.

Your vacuum is good. Your engine must be in good shape. Work out the plumbing and you should see some boost. Now if the turbo is too big you may not see boost. A turbo that is too big cannot spin up like it should.

The gauge has been corrected so zero is atmosphere. Just like when you put 30 psi in your tires you actually have 44.7psi technically smart guy. It's no coincidence that the perfect air to fuel ratio is 14.7 to 1

The exhaust pipe looks kinked. Have a muffler shop make up something better with smooth bends!

You keep saying his turbo may be to big but did you even look it up quick? It's apparently the PERFECT size for his 1600cc engine

That may be but he is not getting boost. That mickey mouse pipe set up is a boost killer.

He didn't answer back about the wastegate either... That's also a potential boost killer and I can't argue the piping could use a redesign/resize

I do not see any waste gate. If he ever gets the pipe sorted out he may get too much boost. I had a buddy who had a similar setup in a dune buggy. It was lightening fast for a couple of seconds until it hit maximum boost where he had to shut down to prevent detonation. It was the fastest thing on the dunes!

According to the pic I looked at it should be just under the compressor outlet (the way he has it mounted)

Clearly the waste gate setting needs to be checked if it has one. The information I have found says the WG is optional.

Well I just learned something tonight. Lack of a wastegate would mean that the turbo would have to be perfectly sized to the engine and would only produce boost at high to max rpm which, that motor may not be able to reach a high enough rpm anyhow. There many factors in play on this one, I hope to original poster keeps us posted! Lol

It does have a wastgateand it is not stuck open

Lack of feedback means this thread is dead Fred.

Did you check when the waste gate opens? My opinion is that this is a piping issue along with a carb that is too small. A 2 barrel Weber might be what you need.

Ok I will go over all of the piping

When I rev the car up it goes to about 7lbs of vacume and when I drive it it goes to 0 so could it be a breathing problem like not getting enough air

Yes it does sound like it. The vacuum reading when you rev it up indicates a restriction in the intake, I'm sure that with a turbo there will always be a minor one but 7 inches of mercury sounds like too much

Ok I will change that pipe sometime and let u know

Cool. It would be a good idea to research cars with similar sized engines as yours that came from the factory with turbo and see what size piping they're running so you have something to use a reference. The drawback to a draw though system is that a stock carburetor size will generally cause a restriction whereas pressurising it will overcome it to a degree. Someone please correct me if I'm wrong with that last statement

And btw, of you have an auto recyclers in your area check out some turbo Volvo and try and snag their turbo piping if its the right size for you, I made a complete CAI from one for my 1.5L engine by cutting it up and connecting with couplers. It was 2 inch and had alot of twists and bends on it

Ok