MarkW

If this is correct why do the magazines make a big deal of the new 911 Turbo pushing a "high 14 pounds of boost" Also, on the 5000 TQ what is boost pressure on that? My brothers will rocket up to 2.1 BAR, but on a 89 200TQ I test drove before I found my S4 wouldn't go above 1.2BAR. So what should the BAR Read on both the S4 and an older 5000 unmodified?

Jason C

2.1 bar is 1.1 over the 1 bar mark, so it's about 16psi

Jim

Many people calculate it as pressure ABOVE normal atmospheric. I believe your Audi's includes the 14.8 atmospheric in the total. I do not believe that the S4 engine is capable of an additional 30psi on top of that.
How did that 200TW feel? It is very possible that there was a leak somewhere in that system unless it calculates the boost differently. I don't know exactly how Audi sets up the different cars that have boost displays. My car doesn't have the display (92 only for the S4.)
Jim
93 S4

MarkW

Thanks for clearing that up. I didn't think it could run 30 lbs.

MarkW

the 200TQ was a dog, my old 1.8T at the time would have killed it

Todd W

If you put in the right turbo

Walt D

The exact conversion from bar to psi is 14.5

Jason C

get new pistons and rods, and balance it out. Probably get the cylinders honed.

For 30 pounds you would want the bring the CE down to atleast 9.5:1 ???

Todd W

I have seen 33psi in bone stock long blocks. 450hp seems to be the limit before rods bend. All you need is an upgraded EM, turbo, exhaust, chip, injectors, and a very large IC.

After that, rods, pistons, and maybe cams or some other head work.

The 1.8T can also handle amazing boost levels.