I thought Turbos needed Intercoolers?

[autobonrun]

This months Excellence has a nice 76 Turbo 911 without an intercooler. When did Porsche first start putting them on their turbos? Why does the 76 not need one; that is, is there a HP level where the intercooler is required?

Nice seeing a car the same color as mine. I've only seen maybe two other tobacco metallic 911's in the last 15 years.

[TimT]

Cars with turbos work better with intercoolers, when you compress air it becomes hotter, and less dense. This is a bad thing for making power. So Porsche started using intercoolers to be able to more safely make more power.

Porsche wasnt the first to cool the charge air though, it was developed in world war two for supercharged aircraft engines.... Perhaps in germany but Im not sure.....(maybe BMW developed it? or Rolls Royce?), or it might have been developed in the states.

Im sure others will offer more detailed input

[GoodMojo]

Porsche starting intercooling the 930 in '78 with the introduction of the 3.3L engine. Intercooling allowed them to raise compression to 7:1 (76-77 had 6.5:1). Turbo boost remained the same @ 0.8 bar. From what I understand, intercooling is necessary to prevent detonation if compression is to be raised so it's not really tied to the HP level.

I don't know if this is accurate or not but I've read that Porsche was the first to "solve" the turbo lag issue (compared to turbo charged cars of that era) by keeping the turbine "primed" when off boost.

[dtw]

The first production 930 to receive the intercooler treatment was the 1978 model. The displacement was also increased from 3.0 to 3.3 litres.

Per equal intakes of air, more and safer horsepower can be obtained from a cooler charge. Thus, intercoolers allow higher boost pressures; additional boost can be obtained at the same effective temperatures as intercooler effectiveness increases.

[Embs]

Originally posted by TimT

Porsche wasnt the first to cool the charge air though, it was developed in world war two for supercharged aircraft engines.... Perhaps in germany but Im not sure.....(maybe BMW developed it? or Rolls Royce?), or it might have been developed in the states.

I do believe Japan was the first with Mitsubishi planes and turbo-supercharged 1420 HP Kasei 23c engines for the Zero's


I was wrong in a good way!

Porsche, Ferdinand: appointed chief engineer of Mercedes in 1923. Created the classic supercharged Mercedes range of the late 1920s which culminated in the SSKL (Super Sport Kurz Leicht) with its massive "elephant blower" supercharger.