FS: 3 uncracked ceramic coated 931 S2 exhaust manifolds
06-07-2013, 02:00 AM
#1
Former Vendor
Thread Starter
FS: 3 uncracked ceramic coated 931 S2 exhaust manifolds
As per title, I have three uncracked, ceramic coated (inside and out) 931 S2 exhaust manifolds. The only caveat with these pieces is that each one has a broken stud in the blind hole on the 3-bolt flange. These will need to be drilled out and heli-coiled.
Here's a pic of one of the three:
Price: $300 EACH + shipping
To purchase or make offer:
Click here for Mani 1
Click here for Mani 2
Click here for Mani 3
Here's a pic of one of the three:
Price: $300 EACH + shipping
To purchase or make offer:
Click here for Mani 1
Click here for Mani 2
Click here for Mani 3
04-19-2015, 09:20 AM
#5
Former Vendor
Thread Starter
1979-1980 924 Turbo = 931 S1 (series 1)
1981-onward 924 Turbo = 931 S2 (series 2)
There were several minor tweaks and updates that distinguish the S2 from the S1:
- improved turbocharger oil drain line
- improved routing for head breather
- improved exhaust manifold (less susceptible to cracking)
- change in turbocharger compressor wheel (brings boost on sooner, but runs out lower in the RPM range; purportedly for improved streetability)
- the S1 Audi throttle body that was also used on the naturally aspirated cars was replaced with a round Porsche throttle body (same casting as on the early 2.5L 944/924S)
- the round throttle body was necessitated by a change in the upper charge tube, which eliminated the leak-prone ovoid rubber connector on the S1 cars
- introduction of "Digital Ignition & Timing Control" (DITC) which was a stepping stone from the early capacitive discharge ignition system to computer controlled ignition
- shallower dish in pistons yielding another half-point of compression ratio (US S1 = 7.5:1 CR; US S2 = 8.0:1 CR; Euro S1 = 8.0 CR; Euro S2 = 8.5 CR)
- 5-lug 4-wheel disc brakes became standard
- US S2 models got the Audi based gearbox (essentially identical to those in the 1987-88 924S) (all Euro and ROW 931 retained the Getrag G31 snailshell)
- late 1982-onward models got the upgraded HVAC and front sway bar arrangement that appeared with introduction of the 944
1981-onward 924 Turbo = 931 S2 (series 2)
There were several minor tweaks and updates that distinguish the S2 from the S1:
- improved turbocharger oil drain line
- improved routing for head breather
- improved exhaust manifold (less susceptible to cracking)
- change in turbocharger compressor wheel (brings boost on sooner, but runs out lower in the RPM range; purportedly for improved streetability)
- the S1 Audi throttle body that was also used on the naturally aspirated cars was replaced with a round Porsche throttle body (same casting as on the early 2.5L 944/924S)
- the round throttle body was necessitated by a change in the upper charge tube, which eliminated the leak-prone ovoid rubber connector on the S1 cars
- introduction of "Digital Ignition & Timing Control" (DITC) which was a stepping stone from the early capacitive discharge ignition system to computer controlled ignition
- shallower dish in pistons yielding another half-point of compression ratio (US S1 = 7.5:1 CR; US S2 = 8.0:1 CR; Euro S1 = 8.0 CR; Euro S2 = 8.5 CR)
- 5-lug 4-wheel disc brakes became standard
- US S2 models got the Audi based gearbox (essentially identical to those in the 1987-88 924S) (all Euro and ROW 931 retained the Getrag G31 snailshell)
- late 1982-onward models got the upgraded HVAC and front sway bar arrangement that appeared with introduction of the 944
04-19-2015, 04:09 PM
#6
Rennlist Member
I had no idea. I bought an '81 931 from a fellow who thought it was a 924. At the time I knew the difference between a 924 and a 931 (and was senselessly proud of myself for that) but didn't know there were S1 and S2 versions.
Now I feel even worse it got wrecked.
Now I feel even worse it got wrecked.