Another blow thru 1600 build

[John S.]

I think that the pandemic is going to give me free time to start my turbo conversion.

[madmike]

[John S.]

It doesn’t look like much. But, I did spend time on this yesterday.

[madmike]

Sweet! what's the Spec's?

[John S.]

.42 air/ .48 exhaust. Off an 82 Saab.
Worked on the 40 dell drla last night. Putting that on without the mod rings and turbo emulsion tubes to tune n/a. Then swap the ignition, then turbo and fuel system.

[madmike]

That should spool up purdy quick

[buguy]

I had one of those turbos on my 1600 when it was draw through and it didn't spool for crap. Maybe you will have better luck than me though. Mine sounded cool though!
https://youtu.be/rCBaD4MKymc

[John S.]

I got the cam years ago and never could identify it. I think it’s a scat c35. Pulling through engine to cut for dual springs and ad 1.25 rockers. Also upgrading trans mounts. The original build was for economy with dual ict Weber’s. That got boring.

[John S.]

I know I’ve asked this before. But, I’ve been reading too much lately on the topic. Vacuum ports!
BOV off the turbo hat? Distributor and gauge off the end casting or maybe tapped off the center plenum? Fuel regulator off the turbo hat? How about the use of a reservoir can for the distributor and gauge? I don’t feel I need to tap any ports in my single 40 dell. I can tap the manifold or locate a factory end casting with the port.

[John S.]

I’m guessing that if I got vacuum above the throttle plates for the distributor. My cheap turbo ignition would work backwards? Just trying to understand everything.

[Clonebug]

I know I’ve asked this before. But, I’ve been reading too much lately on the topic. Vacuum ports!
BOV off the turbo hat? Distributor and gauge off the end casting or maybe tapped off the center plenum? Fuel regulator off the turbo hat? How about the use of a reservoir can for the distributor and gauge? I don’t feel I need to tap any ports in my single 40 dell. I can tap the manifold or locate a factory end casting with the port.

I can't remember what ignition you are going to run.
You will need a carb ported vacuum signal for a standard distributor. If you have a MAP based ignition then you can run anywhere under the carb for manifold vacuum/boost.
The boost gauge will see both vacuum and boost if it has both on the gauge. If just a boost gauge you can tee it into the turbo outlet.
My fuel regulator sees both vacuum and boost but it is an EFI regulator. For a carb with lower pressures you would tee off the turbo port so it only sees boost.
The BOV will need to see both vacuum and boost but it might depend on which kind you have. Mine opens as soon as it see vacuum from the throttle closing.
You should have a good vacuum signal with a single carb so I wouldn't bother with a reservoir can.

[John S.]

I’m just going to try using a one side of a dva distributor. Thanks.

[Clonebug]

You will need to find a ported vacuum connection on the carb that will match the diaphram on the distributor. Since it is designed for the Solex 34 Pict 3 it might be a challenge to get the right amount of pull for the correct cruise advance. The boost retard will happen automatically if you have the DVDA diaphram. Connect to the vacuum side and the boost will push it toward retard. It will be up to you to figure out how much is right and when it comes in.
I tried one on my blow thru Pict 34-3 and lasted a week before I switched to Megasquirt. If you stay at 6-10 lbs. you might get it to work but anything more you really need to know exactly where your ignition advance is at any time.

[John S.]

I fitted the carb and intake today. It runs. But, I will be pulling the engine for the rest the of the fab work.

[buguy]

Nice. That's what I did when I first built mine. Got it so I knew it ran first, then built the turbo stuff.