1600 turbo build thread

[buguy]

I'd be real hesitant about reusing a 40 year old head, without spending some cash and having a proper valve job done. Unfortunately, if you have a reputable shop do the work, you'll be 300-400 into your free bone stock heads. Or spend a couple hundred more and have a very nice head, with modern port and chamber design, with the ability to cool way better than that old thing.

Makes sense. I figured it would be as good as what I pulled off of it that I would still be running of it hadn't had the crack.

[buguy]

There were different ways to strengthen the heads in that area with the 3 raised parts being one of them. VW's stock chambers are a simple wedge head with more squish and also more valve shrouding.

I thought maybe they were to keep the barrel spaced out.

[buguy]

Now that's the way to put an engine in! Just grab it and plunk it in from the top!

[theKbStockpiler]

Some of the German heads have a square around the circumference of the chamber. I have never specifically read of why the hell they do.

[buguy]

Who knows. I guess they knew what they were doing.

[petew]

On the qu of what size pots... I'd go bigger if I were you. I wish I'd gone bigger now. Quicker spool at lower revs.

[buguy]

Well I have 94mm p&c on the way. Not sure I will use them, but they will be here!
Should I buy straight cut or helical cam gears? I see straight cut take thrust load off and take less hp to run, but are noisy.

[petew]

Helical. Straight cut on the street are nasty. Besides, if you need more HP, just wind up the boost.

[Chip Birks]

If you aren't running big lift or high spring pressure, stick with helical. I can't even here my straight cuts over everything else making noise with my car. Never been a problem for me. I measured the opening on those Panchitos at 1.354". A little bigger than your 1.25 ID pipe. But it wouldn't be a big deal. Just port the flanges a little so the transition is smooth. You aren't looking for crazy high volume flow, you just want to get it to the turbo with some velocity behind it.

[buguy]

Awesome. Thanks guys!

[buguy]

Damn. Ordered my p&c Saturday night and they made it to my house before I did today! From Canada! Cip1

[buguy]

Brought the new p&c to work so the guy can measure them. Or even better show me how to measure then correctly. Hoping they don't need work. Going to check the rings too. I've been reading some of the AA rings don't spring back when spread.

[buguy]

Well the piston gap looks ok.
.0027 on top
.0030 on bottom
Ring gap on the other hand is tight.
.0012"
Not sure what minimum is yet for a turbo but certainly not that tight.

[Chip Birks]

Ring gap is .0012? Holy cow! I just opened mine to .023! A little on the big side, but I also plan to run a ton of boost.

[buguy]

Yeah and they actually tighten up toward the top of the cylinder. I saw more like 0009 at the tops of the cylinders. I'm taking the ring gapper home with me for the weekend. Not sure how far I want to open them up yet. I was thinking somewhere around 0014-0016
My guy said he usually multiplies 5 times the bore size to get the ring gap. So I'm at 3.704" so times 5 is 18.5. Seems a bit wide to me.