Is not the boost builded in the WG's ? If it's so,boost has nothing to do with the pressure in the I/C's..............or am i lost ?? Please someone explain that to me.

 

The waste gates regulate how fast the turbo spins via bypass of gasses around the turbine.

 

I agree with you however the point in question was the relationship between pressure and volume of flow with all other constants unchanged. Like you said, build a rig, hook up an air compressor, and see at what PSI the end tanks pop off.

 

should be. if P=F x R and it does. 1.5 =Flow x (Resistance)

i don't know a good value for resistance in the turbo plumbing but is relatively constant as your piping is always the same. so just pick a number like 1000. resistance is a function of tube length, diameter and viscosity. but these are constant for any set up. just plug in a number for resistance.

1.4 = F x (1000)
1.5 = F x (1000)
1.7 = F x (1000)

 

True, but I take breaks for the epic

 

I've been asked opinions on these and honestly for a smaller HP build the cost factor favors these any day of the week. Though honestly at anything 550rwhp or more I'd do a full sized IC. I had Blown6's on my GT3076/K24 (old hybrids) and then I did 6" when I did the Boost Logic kit. My brother's car has a set of 6" IC on the shelf that will go on as soon as the Tilton comes off backorder.

I'm not a Engineer by any mean, but I go by actual experience (not what this number x number = HAS TO BE THIS)... 1.6bar on a K24 (using as example) and 1.6bar on a GT55 is the same amount of restriction but you all forget about the volume... The amount of air being moved in is a LOT more. I'm not saying you all are wrong on the reason why it broke, but its like one thing nobody seems to pay attention.

 

I'm just trying to make the point that pressure, which is directly proportional to flow is what is popping these things. its not the flow. as flow goes up and resistance stays the same pressure goes up. it has to.

Just for reference flow (F) IS volume, whether its high, low, big turbo, small turbo, no turbo.

 

I'll try to shed some light onto Ben's (bad107) dilemma. Engine's can "flow more at the same psi" when volumetric efficiency (VE) or density ratio is increased (or rpm but assume that didn't change). When he bolted on his A28s vs K16 hybrids, the VE of the engine went up due to better compressors, compressor housings, turbines and turbine housings (density ratio probably went up slightly as well with a more efficient compressor). When his VE and density ratios went up, the mass flow rate (MFR) capability of the engine went up. With the same settings on his boost controller, boost would have dropped (boost is a measure of restriction like pumptech said) and he would have had to have adjusted his boost controller (turned it "up") to make the same amount of boost as before. Every intercooler core has some amount of pressure loss the will increase a flow is increased, that is to say that the static pressure on the inlet will be higher than the outlet. In Ben's case, running 1.7 bar with improved VE and thus improved MFR likely put the inlet tanks well beyond 2.0 bar of pressure which ended with an earth shattering kaboom.

ASLAN, the 16 row coolers will get their own writeup thread

 

bigger turbos produce same boost at lower iat....bigger turbos produce same boost with lower backpressure...so indeed a bigger turbo produce more power at the same boost level...(ore we can say a more efficient turbo produce more power at the same boost level)

i am not a fan of this intercoolers if you pay low iat with more restriction...

 

Just want to give props to Earl3 for your write-up, I used it to install my 997.2 I/C recently and it was much appreciated and saved me some figuring and time. Thanks.

I did end up using extra factory straps, cut a pair to get the right length then tig welded on the edges to join them. Worked great and still spring like stock, I'll post up a few pictures later on.

 

[QUOTE=earl3;3547515]I'll try to shed some light onto Ben's (bad107) dilemma. In Ben's case, running 1.7 bar with improved VE and thus improved MFR likely put the inlet tanks well beyond 2.0 bar of pressure which ended with an earth shattering kaboom.


Ben blew the end tank on the first set soon after he put them on at 1.5 bar... plus his hose kept popping off at the lower end tank- I made custom aluminum fittings to hold( It did). Then he blew the second set of end tanks at 1.7 bar... all on A28s...
BTW, I made him do a pressure test( I had no interest other then he purchased a exhaust from me a year ago) because he was asking me to help him find some problems... Had he not done a pressure test on the car from the turbos he would never know his endtanks are leaking...
So I suggest those who have these ICs do a pressure test to 20 psi from the turbos... if it holds smile and keep on driving..
markski

 

The 997 GT2RS runs a peak boost of 1.6 Bar. I am having trouble understanding why Ben had problems at less pressure? Is this a problem with his set of intercoolers or an inherent problem with the design of the OEM ICs?

 

The first intercooler did not really blow, it developed a leak along the edge. I am sure it would have blown soon though

I sent the intercooler to Porsche and they sent me a new one under warranty.

I just sent my current broken intercooler back to Porsche as well. The replacements will be on the marketplace soon

 

It seems like the plastic end tanks are definitely a weak link even at 1.5-1.6 bar. A28s spool up very quickly and perhaps that "hammering" causes more fatique than a vtg with a more gradual increase. I don't really know--just speculating. Could be boost spike too? Without doing a controlled test with accurate measuring instruments and a number of ICs for statistical relevance, it's all speculation. That said, there seems to be enough cases to question how solid these things are built even at 1.5 bar, i.e. do they start leaking over time?

 

sorry for misquoting... I recall the leak was at less then 1.5 bar... you even sent me the video... lol
I suggest those who are doing work around the car next time to pressure test the car... its good to do at least once a year anyways...