The Happy Crab

Instant-G 993 Exhaust Systems for 911 3.6 Conversions (Also works GREAT for 3.2!)

Happy Crab with SC/Carrera dual outlets and oval heat exchangers

For 993 Engines – Specify oval or round

  • $1195 for the Happy Crab alone, with tips, $1095 with plain tips. (Trust me, get the tips!)*
  • Specify outlet, 993, 964 Dual Outlet or 911 1974-1989 Dual
  • Also available for RS bumper 1969-73, +$250 see below

Pricing with rotated flange for 3.0, 3.2 and 964 engines:

  • $2195 Complete with “Happy Crab” muffler, with all under-engine plumbing for heat (All 911 through 964)
  • $1895 for heat exchangers, rotated flanges and the Happy Crab only, with tips.
  • $1195 for the Happy Crab alone, with tips, $1095 with plain tips. (Trust me, get the tips!)*
  • Please note:  If you are ordering just a Happy Crab, we need to know which exchanges you have.  The Happy Crab RS (for long hood cars) is only available with the Bischoff/Oval heat exchanger option.  Click here for a description.

*When ordering, we need to know which variant of the headers you have, round or oval.  All photos on this page are of the oval crab, this refers to the gasket flange shape on the header outlets.

Here are the gaskets, oval (Bischoff) and round (Gillet).  The easy way to identify them is that the Oval has an absolutely straight lower surface, whereas all surfaces are equally curved on the round:

The oval are shown above and below and you can see where the three pipes are welded together.  On the round flange, there is a one-piece welded collector that all three pipes enter near the heat exchanger.

Discount may be applied when purchased with a 3.6 conversion kit.

The Happy Crab includes 100% stainless oval resonator tips

hc2 hc3

Hence the name Happy Crab


Price DOES NOT include the CF heater tube shown below.

Complete System includes:

  • Factory 1-5/8″ 993 Heat exchangers (modified for 964 by rotating driver’s side flanges, welding and precision surfacing)
  • Heater distribution tubes -w- factory rubber elbows
  • Stainless hose adapters and high temp silicone tubing (About $50 in tubing)
  • All required clamps, brackets, etc.
  • Complete instructions and tech support

Note: You may supply your own 993 exhaust. Modification prices are as follows:

Rotate header flanges and surface mill $295
Complete Flapper kit, with adapters, 55″ hi-temp silicone hoses and clamps $135

WP_20160211_07_00_13_Prosm WP_20160211_07_00_54_Prosm

Factory components available separately:

Headers $575 per pair unmodified, $795 modified
Catalyst $385 unmodified, $595 with straight tips.
Heater distribution aluminum casting with factory rubber elbows $295
993-211-039-02 (2)
Catalyst bracket with clamps $65, included with catalyst
993 Short Pipe (joins CF tube to sheet metal) 993-211-034-01 $25

Please note: The heat exchangers shown below were customer supplied. Ours are generally in much better condition. They were also shown with teh old clamp-on reducers.

Finished Product: