Instructions to mount a T/A duct-tail spoiler

[340-FOUR- BARRELL]

UPS delivered a T/A duct-tail spoiler yesterday. Seems like instructions are not included by the vendor. The spoiler is going on a 73 Challenger, The trunk lid has no predrilled holes or cutouts for installing the spoiler. I did many searches for instructions and only came up with a dubious diagram of where the holes go. The 3-1/8" distance from the curve of trunk as it turns down seems wrong. I believe this dimension/distance is to the rear edge of the trunk lid where the trim is . I made a card board template, taped it down, marked where the holes are to be drilled, and it seems right. Have a picture of the backside of a T/A trunk lid that shows where the cutouts go. Not sure about where the supplied washers go. The washers have burrs around the bolt hole and may act as lock washers or jam nuts on the mounting bracket? TBD. Some of the T/A's I've seen on eBay or in books show a gap between the trunk edge and the spoiler of about 1/4" where body color is exposed, other pictures show no gap and the duct-tail spoiler is flush with the rear trunk edge trim. What is the correct spacing. Thanks for any suggestions. 

[Tantster]

 

[340-FOUR- BARRELL]

I believe the trunk lid on the stand had a wing spoiler mounted on it and not a duct-tail spoiler because it has two square holes on the bottom on the left and right side for mounting the stanchions that support the wing. However it does have the cut outs for fastening a T/A duct-tail spoiler. Hmmm. Pass some of that popcorn over. I've deduced the four serrated washers for the main bracket's studs are pressed onto the mounting studs before positioning the spoiler while screwing the corners of the spoiler to the trunk lid. Hence, must secure the spoiler with the supplied 1/4" screws first, before installing the 3/8" nuts that hold the center of the spoiler in four places to the lid because the studs offer some leeway or margin for error in the way they mount inside the spoiler. Oh, can't forget to seal all drilled holes with silicone to make water tight. I'm in no hurry so going to ponder this a bit more.

[1 Wild R/T]

That deckled has provisions for a wing or a T/A style spoiler but hasn't been drilled for either.... The four outboard screws were originally 10-24 & the four inboard T bolts were 1/4-20... The holes are intentionally oversize to allow for variances.... As you've discovered the flat push-on retainers mount the T bolts to the spoiler...   AAR spoilers were mounted about 1/2-3/4" forward from the back edge of the deck lid but T/A spoilers were less then 1/4" from the back... If viewed from directly above the spoiler appears to be all the way back but the lower rear edge is drawn back under the spoiler so a small amount of paint gets exposed...

[340-FOUR- BARRELL]

Wild, Thanks for the lucid explanation. Your comments verify my findings. I wasn't aware the positioning of the duct-tail spoiler is different for the AAR. Year One emailed me yesterday to say the T/A hood I ordered will arrive on Thursday, 11/2. Hope the hood comes with a diagram or instructions. Cheers

[1 Wild R/T]

Glad I could help....

[bc3j]

My T/A spoiler was added to my car and was installed exactly as 1 Wild R/T stated. Question for you. I read somewhere that the TA spoilers were not installed at the factory, but shipped with the car to be installed at the dealer. Hence the variation of spoiler positions. Not sure if that is correct. Have you ever heard that?

[1 Wild R/T]

My T/A spoiler was added to my car and was installed exactly as 1 Wild R/T stated. Question for you. I read somewhere that the TA spoilers were not installed at the factory, but shipped with the car to be installed at the dealer. Hence the variation of spoiler positions. Not sure if that is correct. Have you ever heard that?

Front spoilers were in the trunk... Rear spoiler was installed....  I believe the T/A-AAR exhaust tips were also in the trunk...

[340-FOUR- BARRELL]

The T/A spoiler install required buying a DREMEL Mandrel and Cut-off wheel kit. The discs  are 1-1/2" dia with reinforced centers. The diagram posted above was instrumental in drilling the holes.

[Rdchallenger12]

That looks good! Great work