TiAL 605 specific discussion
#21
you can get better low end thrust than my car with rods due to the added timing you can run. my car runs a low amount of timing advance from 3000-4500, so the boost from the RS6's wont break a rod. you could do the same thing with RS4's and get even better low end torque.
#22
have you ever heard of a k04 car throwing a rod?? yeah.. its happened before, itll happen again. it all comes down to tuning and hardware. people get too aggressive with timing, cause we all know that k04's run out of breath past 22ish psi, and the first thing to go is the rods. they are the one weak point of these 2.7 engines. if you wanna get super aggressive with a 2.7, first thing to install is rods, anyone will tell you that.
look at my timing chart. notice the timing curve, not near as much timing early around 3000-4250. then on the upper end its 20 degrees or so. imagine the power and torque youd get if you had 20 degrees when the RS6's peak surge and boost hit??
and the rods dont just "add" the power, its from a tuning stand point. it can be tuned more aggressively due to the fact that the rods arent going to buckle.. sorry if i mislead with that...
look at my timing chart. notice the timing curve, not near as much timing early around 3000-4250. then on the upper end its 20 degrees or so. imagine the power and torque youd get if you had 20 degrees when the RS6's peak surge and boost hit??
and the rods dont just "add" the power, its from a tuning stand point. it can be tuned more aggressively due to the fact that the rods arent going to buckle.. sorry if i mislead with that...
#23
well, you've convinced me on the 605s. I have read a lot of speculation of the exhaust side of the 605 being engineered too tight. Some people say it was a design thing so they could say that the 770 spool almost as fast. Who knows, this turbo seems to have a lot of mystery around them. If I can make 500+ awhp on the stock block then I'm sold. Thats my build goal and if I can keep tuning it for more later AND they sell for less than the RS6... yep.
#24
call tony @ EPL. tell him richard k shot you his way. hell tell you with a good water meth setup (aquamist has a failsafe) a free flowing exhaust, and good intake cooling (phenolic spacers, AWE or ER intercoolers) you can get very close to that number safely.
http://www.eplabs.net/products/vag/t...0-bolt-on-kit/
http://www.eplabs.net/products/vag/t...0-bolt-on-kit/
#25
have you ever heard of a k04 car throwing a rod?? yeah.. its happened before, itll happen again. it all comes down to tuning and hardware. people get too aggressive with timing, cause we all know that k04's run out of breath past 22ish psi, and the first thing to go is the rods. they are the one weak point of these 2.7 engines. if you wanna get super aggressive with a 2.7, first thing to install is rods, anyone will tell you that.
look at my timing chart. notice the timing curve, not near as much timing early around 3000-4250. then on the upper end its 20 degrees or so. imagine the power and torque youd get if you had 20 degrees when the RS6's peak surge and boost hit??
and the rods dont just "add" the power, its from a tuning stand point. it can be tuned more aggressively due to the fact that the rods arent going to buckle.. sorry if i mislead with that...
look at my timing chart. notice the timing curve, not near as much timing early around 3000-4250. then on the upper end its 20 degrees or so. imagine the power and torque youd get if you had 20 degrees when the RS6's peak surge and boost hit??
and the rods dont just "add" the power, its from a tuning stand point. it can be tuned more aggressively due to the fact that the rods arent going to buckle.. sorry if i mislead with that...
Of course timing advance is less at lower rpm, the engine isn't turning as fast so it isn't necessary to begin the burn earlier. A great amount of timing advance is not a good thing, the combustion expansion begins to happen while the piston is still rising, which is hurting power production. At lower rpm's the engine is also more susceptible to knock since the end gasses have more time to cause an uncontrolled burn. Somebody trying to run too much timing at a lower rpm is likely to cause detonation, and that could result in rod failure. That's probably why you've seen rod failure on K04's, because of detonation, not too much torque being produced.
I understand that the rods allow for a tune that produces more torque, but if the turbo, K04's, can't produce a level of torque sufficient to damage the connecting rods then putting in aftermarket upgraded rods is not going to lead to a performance enhancement.
The reason 605's can use upgraded rods is because they can pump more air than k04's. More air allows for more fuel, which ultimately is what is producing the torque. Timing doesn't produce power, there's simply an optimal timing advance that allows for the extraction of the most power.
#27
A built block for k04s? That seems excessive. The only reason I can see doing that is to swap all the internals for lightweight pistons and rods, new rings (brand new compression is great) and a balance of the crank. I didn't really think that the k04s were capable of enough power to justify a build on that scale. Please post those plots when you get them because I'm curious to see the results as well as the RP durability.
#30
Do you think you would find any effeciency improments rebuilding block with lightweight components? I know that with the 110K miles I've got on my a6, I've always wondered if I should buy a compression tester and see if I'm losing anything.