[HWYSTR455]

Originally Posted by Skip Fix

So some real track time data on my 78 I posted in the exhaust section thread.

I had 3" H pipe 2 chamber 3" flowmasters and 2.5 mandrel tailpipes omn the car for legal NMCA classes when I ran the RAIV 400. Dropped in the first E head 455 with a 259/262 @ 0.050 solid roller. It would pick up 0.2-3 sec open headers over closed exhaust with mufflers and pipes still on the car. While swapping tranny and convertor noticed mufflers and tailpipes were rusty so pulled the whole system off. Took it to the track and did some tuning. Then add a 3" Dr. GasX and 3" Ultraflows into 3" Torque Tech mandrel tailpipes. Even with the additional weight of the system the car ran identical. 1/8 6.9s @ 99-100 1/4 10.90s @ 123 with that motor.

That's fairly real-world results. But I wonder if the X over the H was the determining factor? Or contributed the most to the difference I should say.

2016 Hellcat Charger with drag radials has done 10.7 in the 1/4 by some trade rags, with a few upgrades, it would be in the 9s. BUT, you toss a blower on a Pontiac, where do you think you would be? Or even just build an IA2 for the $40k+ you would save?

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