Map Issue

[Steve4694]

@Mituc We at 85kpa pressure so 200kpa is 1.15 bar boost. Our stock tune in RSA for our altitude and crap fuel we peak at 1bar and drops off very quickly. On our stock tune we peak power at 5000rpm or there about. I have not done upgraded engine internals yet and the chance of getting a bad batch of fuel is very high which will bend a rod. Already had an engine replaced due to a bent rod and busted big-end bearing. On a good tune stock turbo up at our level we were flowing 220g/s at the most with a 3" intake, so 280g/s is a far better looking figure.

@Steve Thanks for posting the compressor map, makes a lot more sense of things. I am still then wondering if the WGA spring is not too high for my stock engine internals combined with our tendency to receive such bad quality fuel. The big guys from a dealership here rate that with stock internals at our altitude we should not run more than 230wkw and 1.2bar boost.

[Kevin]

This is very interesting. Steve, I suggest we move to the coast

[Steve @ VersaTune]

Altitude only affects the flow you can get out of a turbo. It has nothing to do with the load that an engine can handle. There are plenty of people running 2.5+ load on stock internals. Your fuel situation has the most impact on what load you can safely run. Slowly bring up the load and see what timing it can handle without knock. You will see 2.0+ load with that WGA spring at WOT. If you want to run less, you can throttle the engine with the DBW tables until you replace the WGA.

[Steve4694]

So can I run a load of well over 2 as long as the engine sees little to no knock at this altitude? I am capped by turbo flow and fuel supply.

[mituc]

Pretty much. Just increase the per-gear load slowly until you approach like 230-250kPa MAP and you should be fine. Start with conservative advance timing values (1-2 degrees below stock should be fine at high rpm, past, say, 5k) and see what you can get. Make sure that the load/boost tables in the Absolute Limits section as well as the Baro specific load table are changed accordingly.
However, keep in mind that with such a stiff spring in the wastegate you can boost spike quite easily. I wouldn't start tuning the load until this issue is resolved (softer WG spring, 12-15 PSI).

Don't go too much over load 2, 2.2-2.3 or 2.4 max is the safety limit you should have in mind on stock connecting rods. You can run load 2.5-2.6 but not for long.

[Steve4694]

Thanks for the advice. Took a run now with BCS DC about 5% and the car holds around 235kpa with 0.35KR at a load of 2.1. The per gear loads are set at 1.74 but still getting over 2. Will try and get that spring in as soon as possible. Just confirming, 1-2 degrees below stock and then advance if no KR is seen? Investing in K1 rods or similar soon.

[mituc]

Just confirming, 1-2 degrees below stock and then advance if no KR is seen? Investing in K1 rods or similar soon.

This is what I'd do, but maybe Steve or other knowledgeable guys will share their opinions..

Btw, how much time does it take to swap the connecting rods? I'm thinking to get some rods and take the car to the dealer to have them replace the rods.

[Steve4694]

I have been told a lot of different stories when it comes to that. One mechanic said 2-3 days as he needs to pull the entire motor out and another said he can have it done in a day. Here in SA no one is willing to work for their money and when they do work they charge an arm and a leg. Will cost me the price as the rods to fit them.

[Steve @ VersaTune]

I've rebuilt my engine once, and pulled off the cylinder head once after that.

I will say that it is a nightmare to work on these engines due to the tight packaging and layered components. It would be at a minimum a full day project with air tools and experience with these engines.

While you've got the head off, why not put head studs in too. The stock bolts are TTY and should not be reused.

[Kevin]

Steve, i know a few mechanics at VW. i can maybe convince them to help us out if the need arises. Cool guys