PP502s (not 520s) on an unmodified car?

An esteemed forum member is offering me a nice deal on a set of Bosio PP502s. There doesn't seem to be a lot of info on these - I gather they have been discontinued. My 03 wagon currently has no mods - anybody have any thoughts/experience with these nozzles on non-modified vehicles. Power, smoke, mileage?

My upgrade plan was to run with just nozzles for a while and then get a tune when I need a new clutch (my OEM clutch has <100K kms on it). Would these nozzles be suitable that that path?

I think they're a little big for an untuned car with a stock turbo. Or a tuned car with a stock turbo, for that matter. You'd be better off with 520s, either the 4 or 5 hole ones.

In what way IBW? Meaning what would the symptoms be? Smokey? Poor mileage? Uneven power delivery?

Who's selling the PP502s? Are they located in Canada?

Talk of such-and-such injectors being too big are because people push the pump voltages and injection durations in the tuning to the point of a tire fire. I will rather put PP502s or even Race520s with very conservative fueling maps - heck even stock - than to eke out every bit that smaller injectors are worth.

I have been keeping a dirty little secret for years in my car. It has a Van Vught Tuning (Turbo Johan) tune from when my car was in Germany with a little side trip to Holland while en route to being put on a boat to come to Canada.

The car came in exactly 15 years old with 212k km on the odometer. In the intervening years the original pump started to leak; replaced it with a 12mm one I had sitting around. And I installed a 3 bar MAP sensor and in both cases I never remapped Johan's original tune, knowing that I would simply get 20% more absolute pressure everywhere.

Well I've had my car 5 3/4 years and it now has just over 350k km, with original engine, original .205 injectors that came with my AFN and yes, even original turbo. I don't need to top up any oil between 12000-15000 km OCIs, get 1100 km of CITY driving per tank consistently (except in winter) and the exhaust is much cleaner than I have seen coming out of many newer Diesel pickup trucks that roam our local streets.

All this to say that you can have big fueling hardware if you have a conservative and well-developed tune, which I know Johan's to be (he is in a locale where German autobahns are a short drive away and tuned cars need to last in that environment, unlike here to advertise big numbers and smoke while knowing that we live on a continent where typical driving would be to put on the cruise control at 120 km/h for as long as your bladder will permit.

Oh, and it helps to know what you're doing too.

I see that the OP has an 03 TDI Wagon. Very nice! You get 5.6 L/100km - my last tank of just under 64 litres got 1150 km of all-city commuting, plus my car has AWD.

With stock maps (not tuned), you may find you have to bump the IQ number 'way up to get rid of smoke. That can make starting harder. And you could take a FE hit.

Folks here have been debating the merits of larger versus smaller nozzles for years. I'm more in the smaller nozzle camp. You're hearing both sides here, and probably not conclusion: You'll have to make your own choice.

Well duh, if you put big fuel hardware on the stock ECU mapping, you are throwing more fuel - without the ECU knowing about it - so the solution is simply to trick the ECU twice by throwing more air into the engine as well to balance the lambda, again without the ECU knowing about it. Whether with a boost bleed as was done in the wastegated TDI days or with a 3 bar MAP in place of 2.5, its the same sort of idea.

Of course, I would never suggest to take the route of ECU trickery to anyone over a proper tune, because the chances of diminished turbo life or a blown one at worst are high. I decided that I'm my own warranty and I have a GTD1752VRK on the ready.

Yah, sounds like these are too large for my application if I want to go some time with the stock ECU map. I'm looking at DLC 520s or 1019s ideally.

TDIMeister said:

Who's selling the PP502s? Are they located in Canada?

Click to expand...

Yup.

http://forums.tdiclub.com/showthread.php?t=492827

Thought the DLC 1019 took the place of PP502after it was discontinued?

PP502s are still made, although production runs are infrequent. In fact, Bosio is making most rotary pump nozzles less frequently. Remember that Europe transitioned away from rotary pump TDIs in 2000 or so, a long time ago. So Bosio and Firad, the two larger nozzle makers in Italy, focus more on common rail nozzles these days. You can still get the nozzles for older cars, but it can be a struggle.