2.4 Bar Boost

[audiman]

I agree Marco. There is a limit. You need decent ignition advance to get decent power. If you can only run 2degs then its no good

[Billman]

Maybe Mihnea has tuned a car with such boost! He could tell us about ignition timing and other hardware issues!

[audiman]

Maybe he has. But trust me you need low compression.

[Billman]

Yes no prob! If you het boost so low then low compression (8.2:1 for example) is not an problem! Maybe driving 2 RS2 Heag gaskets + 1 mm at the valve pokets to have also a non inteference engine!

That sounds good he? would 2 gaskets (the one over the other with all layers??) hold that boost?

[audiman]

No, 2 gaskets wont hold that boost in. You will need a custom gasket to make it last and also ARP studs.

[Billman]

And how thick must it be to get with 1 mm deeper valve pockets ca. 8.2 : 1 CR ?

[quattronutter]

No, 2 gaskets wont hold that boost in. You will need a custom gasket to make it last and also ARP studs.

my old ur 10v with k26turbo and all the other bits used to blow head gaskets at 1.6 to 1.7 bar every 2 months,it stripped 2 headbolt threads the last time,so uprated bolts are a must!!!

[audiman]

I quess you want the centre part of the headgasket to be about 1mm thick. Ask Marco to work it out if he can be arsed

[audiman]

thats the old paper gaskets right?? The RS2 item is multi layer steel gasket. It last fine with big power. And im still usng RS2 headbolts! No sign of any head problems.

[quattronutter]

thats the old paper gaskets right?? The RS2 item is multi layer steel gasket. It last fine with big power. And im still usng RS2 headbolts! No sign of any head problems.

i used a steel gasket the last time it went,final time it ripped the threads out the block,i think they were weaked by too much boost and old engine block,the old sport quattros used bolts that went right through to the sump,can understand why

[Billman]

I also have no probs with the RS2 HG! Many people drive with RS2 HG without any problems! I have heard about the 5 cyl diesel HG that they come in 3 forms of thickness! They should hold boost! The diesel has very high CR!!!! Only prob is that a hole must be enlargen! Anyone knows more about this??

Maybe a BILLMAN MOD ???

[Albert]

About the ignition timing, I think there should be a compromise over ADVANCE vs. BOOST that works best, but as a rule of thumb I would say the best performances are achieved while tuning the best ignition advance at medium boost, then increasing boost up to where pinging starts.
There are many drawbacks in raising too much the boost while being then forced to decrease ignition advance to eliminate pinging:

1) decreasing ignition advance form what is optimum will reduce engine performances;
2) higher boost means higher charge temperatures which cause:
2.a) less charge density (therefore less power, again);
2.b) increased pinging (which takes back to reducing ignition timing again).....

So there is a point at which increasing boost will actually produce inferior outputs.....


Marco

IMO there is a point where You have optimum turbo compresor preformance, it is where the air temperature is the lowest or close to the optimum temperature .... with the lowest temp. the air is most dense, than You should increase the advance ... right ?

[audiman]

I think so, im not a tuning expert. I just know from my own experience.

[Billman]

We are going a little off topic (Thema is 2.4 Bar) but this is what i have found about the Diesel Headgaskets! Maybe someone of the stroker boys could help on the differences between diesel block and 2.2 head!

[audiman]

Diesel headgaskets are measured according to piston protrusion. IE how high over the block deck the pistons come.