What's involved in a turbo upgrade?

Upgrades to the 1.5, 1.6 and 1.9 engines that make them go farther or faster
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Una
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What's involved in a turbo upgrade?

Post by Una »

Say I wanted to toss a turbo onto my '81 Rabbit. And assume I'm intimately familiar with installing turbo's on motors (gas ones, anyways) so I can figure out the manifold and plumbing and stuff. The part I'm not familiar with is doing it on a diesel.
I see I can toss a gasser intake onto the motor to make plumbing the turbo up simpler (less likely to blow up the big plastic intake muffler thing that the N/A diesel has). What about the fueling, do I need a turbo injection pump? I'd kind of assume that I do.. Turbo injectors too?
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bscutt
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Re: What's involved in a turbo upgrade?

Post by bscutt »

you can run a turbo without the turbo pump which will essentially make it an "eco-diesel" although you won't have the extra features of a turbo block like the oil squirters for the pistons which help keep the pistons cool and properly lubricated. You will definitely get some benefit from the turbo without having the fuel boost features of the turbo pump but if you want the full turbo effect you will need the turbo pump. If your 81 as the 11mm head bolts instead of the 12mm, you may want to reconsider this mod unless you re-do the head gasket and use head studs to secure the head. If you're going with a mild boost you may get away without doing this, at least for a while.

Fatmobile has put a turbo on a 1.5L NA engine if I recall, don't remember if he went for the turbo pump or not. The 1.5L also used 11mm head bolts so that may be a good point of reference for you.
Bob

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Una
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Re: What's involved in a turbo upgrade?

Post by Una »

I was told when I bought it, that it's an 82 motor, so it should have 12mm headbolts.
I definitely have a hard time wrapping my head around diesel engines.. How does the extra air get utilized if the pump doesn't know it's there?
Good to know it'll work though. :)
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Re: What's involved in a turbo upgrade?

Post by bscutt »

These diesels can benefit from extra air - I don't think they breath very efficiently. You can also turn up your pump a little bit to over fuel so that and the turbo give you more oomph. A less restrictive exhaust is reported to help too although I haven't personally tried any of these mods (yet...)
Bob

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the vegenator
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Re: What's involved in a turbo upgrade?

Post by the vegenator »

Yeah these NA diesels (naturally aspirated) are supplied with unlimited air into the cylinder, which is one of the things that makes them intrinsically different than gassers.

I'd add boost and egt gauges if you want to be extra careful. These 1.6 NA engines aren't made for turbos.
- Mike Harpring

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Re: What's involved in a turbo upgrade?

Post by Fatmobile »

The NAs do great with a turbo.
Very few people have destroyed one by putting a turbo on them,.. I only know of one guy who pushed it beyond it'd limits.
Get rid of gasser thoughts of air/fuel mixture.
You can't burn a piston by being too lean, idle is about 200 to 1.

More fuel; moves more gasses through the turbo, which provides more air.

A turbo pump doesn't provide more power,.. it keeps fuel down when off boost.
You can get quite a cloud before boost with an NA pump.
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
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Re: What's involved in a turbo upgrade?

Post by Una »

Fatmobile wrote: A turbo pump doesn't provide more power,.. it keeps fuel down when off boost.
You can get quite a cloud before boost with an NA pump.
Hmm.. That's about how my pump works right now.. Hell of a cloud.. If a turbo will solve that problem, that'd be awesome.
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Re: What's involved in a turbo upgrade?

Post by Corlebra »

Throw a turbo on it!

I't got a 91 ECO Jetta with a motor from an 81 (12mm mech head). I immediately blew the headgasket, however Before installing the engine i decided i better check the torquing of the head bolts and probably over tightened them (70ft lbs). Right away started burning the coolant and over pressurizing the coolant system.

replaced headgasket and new 12mm stretch bolts and it's been running fine. I turned the fueling up a a few turns (idle screw is 1/8" from being all the way out) and i've set an MBC to 20psi (over the 17psi safe level) with no problems. Drove the car 550 miles to Milwaukee last weekend, and 350 miles round trip to Davenport this weekend. I don't drive this thing nicely, coming back from Milwaukee is sounded like a rod was coming lose but i ran the car pretty hard at 85 - 90 mph the whole way back. After it cooled down it sounded fine, pulled the pan the next day and everything checked out fine.

So, as long as you don't run it too hard (under 75mph for extensive periods), I think you'll be fine ;)
91 ECOdiesel- Coilovers - MBC - 30yo 1.6 powerplant :(
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