Like many GT500 owners I started out with the FRPP intake and tune and slowly warmed up to the idea of something more potent, then I stumbled accross a  pulley/tune package  from  VMP Tuning that is specifically for the FRPP kit. The contains a 2.65″ pulley, 90mm idler, SCT Flash Tuner, 3 custom tunes from Justin, and I opted for his stellar pulley puller tool (save yourself the nightmare of the cheap pullers that you read so much about).  This kit is consistently putting down 550RWHP on average, pretty damn stout for a $700 investment.

Woah, not so fast, you have now introduced a new problem that needs to be addressed before becoming a YouTube hero.  As any Shelby GT500 owner already knows, the car suffers from heat soak due to extreme temperatures generated by the supercharger and that rather wimpy stock intercooler. You can drop 60HP+ pretty quick when the temps get up there, which is pretty easy in 90 degree temps.  Essentially, the temps climb and the computer kicks in and pulls timing from the motor to keep it from a meltdown, this in turn saps power noticeably.

So what do you think is going to happen when you swap a pulley from 3″ to 2.65″ and add 3-4psi?  You are going to take an already known issue and exacerbate it.  Solution?  Cooler plugs for one, NGK TR6 plugs gapped at .035 will run one range cooler than stock.  Second, an AFCO heat exchanger to replace the stocker.  I spent some time researching all the various Shelby Heat Exchangers on the market and stats all point to the Shelby dual fan HE and the AFCO as leading the pack. Steeda makes one, and I am usually a fan but in this case it is smaller and more expensive than the afco, huh?  The afco runs about $380 while the shelby fan cooled is around $750.  The AFCO is more than enough for my needs and, I got a sweet deal on a used one from a forum buddy.  Some quick data to back the decision:

Core Size
AFCO core is 9″ tall x 22.44″ wide x 2″ thick.
Stock is 6″ tall x 23″ wide x 1.25″ thick.

Height:
Stock 6″
AFCO 9″

Width: Stock 23″
AFCO 22.5″

Thickness: Stock 1.25″
AFCO 2.0″

Front Face Area
Stock 138 sq. in.
AFCO 202 sq. in. (50% increase)

Overall Surface Area:
Stock 690 sq. in.
AFCO 1616 sq. in. (135% increase)

While it is rather an easy install it is time consuming to get the front fascia off, see pics below.  After driving around in hot weather I can actually tell a difference, while it probably won’t solve your heatsoak issues on a long road race course, it will surely resolve your average street use heat soak.

You will need 1.5 Gallons of mixed 50/50 Motorcraft Premium Gold protection Engine Coolant with Bittering Agent VC-7-B, sold at all Ford dealerships $11.00/gal. The GT500 manual specs VC-7-A but the parts computer has been updated for 2009 showing VC-7-B as the official replacement for that part. Only difference is a bittering agent I believe was added. Any Dealership will carry this don’t screw around trying to find it at your local Autozone, PepBoys, etc.  And it is highly advised not going with some off the shelf product due to the possible chemical reactions within the GT500 cooling system and this foriegn coolant, not to mention the yellow keeps it looking factory.