This is the set of instructions I send out with my heat shield templates:
Both templates are full size. Metal used was HVAC galvanized sheet metal, .015” - .020” thick
Templates must be cut out along solid lines – curved lines follow the inside of the Speedster body
Do NOT cut dotted lines if shown – they are for metal bends or for weather strip mounted on the underside of the panel to seal against the engine tins.
Some noted cut-out locations are optional – check your mounting locations and adjust if necessary. Holes for bumper mounts or mounting bolts are noted – your locations may be different (no two CMC’s, it seems, are precisely alike). Measure and cut as needed.
The Rear, Upper shield
The rear shield sits on top of the CMC rear frame and seals against the inside of the rear of the engine compartment with ¾”W X ½” thick weatherstrip (self-adhering tape on one side, stuck to the body, shield fitting against the middle of the weatherstrip tape – length determined by your body and preference to seal the compartment). There is a 90 degree bend on each end to form a vertical, upward “wing” which seals against the side engine compartment panel where there is a gap at the rear. No other weatherstrip or sealing tape is used. I used “Storm King” weather strip from a DIY.
The Lower shield
Attaches to the under side of the box frame members, across the back and along both sides of the engine compartment. It fits very closely to the VW engine tin and assumes that ALL original VW engine tin is installed. There are two strips of ¾” X ½” black foam rubber weatherstrip on the BOTTOM side of the shield to mate with (actually lay on top of) the outside top edge of the head cooling tins to seal that area. Optionally, you may run a piece of 3/8” wide X ¼” thick weatherstrip on the underside to seal up the rear of the engine breast plate, but if the shield fit is good, this may not be needed.
I drilled and tapped the CMC rear frame for #10-32 screws for mounting the panels. Mounting fasteners used were #10-32 screws with captive star washers under the heads so they stay tight – I also used ½” OD flat washers under the heads. Space the fasteners along the shields to insure that it is properly held on, AND that there are no bulges or gaps anywhere. I noted where I drilled mine, but you may want them placed differently. There is a lot of flexibility for placement.
3/8” thick rubber floor mat (DIY carpet department – Rubber, Shop Floor Mat) was cut to fit the firewall shape and attached to the firewall with DAP rubberized contact cement and hood sound blanket fasteners (they look like plastic mushrooms with a barbed stem – NAPA Auto Parts). The firewall mat was cut long, such that it fits down flush with the front ends of the lower tin, and the two are fastened together with a 2” X 2” angle bracket (aluminum) and #10-32 screws on both sides. The Mat is also long enough to overlap the transmission bell housing, with a space removed for the clutch and throttle mechanisms and effectively seals the front of the compartment, even though it doesn’t completely seal at the front of the compartment – air entering there is cooler from the void between the rear seat back and the firewall, PLUS there is a large cut-out in my firewall for fresh air inlet to the cooling fan.
