Hello all,
Been reading here for a long time, and finally at a point where I have to ask a question. The poor little 1.6 NA in my 84 Jetta finally gave up(Loved that little rattlebox, gov-modded and turbo'd). And wouldn't you know, I got most of a 1998 TDI Jetta given to me the day before, with a complete AHU. So long story short, I've got the engine bolted in with all the stock 1.6 pump and accessory brackets. I have the 10mm head installed in the 1.6 NA pump with an unmodified control lever, but that was just to make it drivable again. She'll barely do 55 mph, but it gets me to work. I snagged a 300tdi Land Rover pump on ebay, and should have it soon. My question is this: Can I get away with running the 1.6 pump bracket(bored out to fit the 300tdi pump), or will I regret not running the stock AHU pump bracket? I've been researching using the Rover pump, and indeed many mTDI swaps, but either I can't find anything about running the Mk1 brackets on mTDI, or I can't remember finding anything.
Thanks to all who put up with my rambling posts and still offer advice:)
you have to run an adjustable pulley for the rover as the pump isn't slotted for adjustment, but as far as I know you should be able to do as expected. MKI bracket should be ok
If you use the mk1 bracketry you lose the roller between the pump and cam. I've heard of people running like that, but I wouldn't. The TDI camplate profile and larger plunger/head make for more resistance for the timing belt. I'd want the added wrap.
Regardless, you'd have to bore out the bracket and accommodate timing adjustment by either running the two-part sprocket or slotting the pump mounting holes.
Good, that's what I needed to know. I have a Mk4 adjustable pulley already, no problems there. I'd be more worried about the loss of that little roller on top if I was going to make any power out of this, but it's just got to be my work beater. I doubt I'll turn it up past 100 horsepower. I'm running the stock 020 trans, so I'm kind of limited anyway. Thanks!
The horsepower output of the engine has little to do with how the timing belt behaves. The pump acts exactly the same whether it's putting out 10% of its maximum power or 100%.
The IDI engines get a fair bit of belt flap along the top with only a 9mm plunger (and the softer plunger springs in the pump needed to keep a lighter plunger in check). I'm not sure however how much the addition of the roller went with the spring loaded timing belt tensioner...
The spring loaded tensioner was added mid-AAZ. The additional top roller was added with the change to the TDI VE pump.