I've been reading a lot of posts and viewing several videos on you tube about the power gains associated with AP Velocity products.Seems that most of what I see is just crank pulley and tune..Is there a reason not to do the blower pulley while you're at it for the relatively small difference in total cost? Are there any draw backs to doing the upper pulley? I do plan on doing a trans tune and pulley/motor tune , but am curious about 1 vs. 2 pulley change. (MY2016 V6 S)

 

The upper pulley is harder to change, as it’s a friction fit (requires a torch), so most people don’t bother for the marginal gain. My memory is that it’s a bit more worthwhile on the V6 compared to the gain on the V8.

 

I think your memory is failing!
All the feedback here is that there is very little gain on the V6 (as evidenced by the 25 HP bump according to VAP) as the stock V6 SC pulley is already damn near as small as you can safely go and the upgrade pulley is only marginally smaller, but the V8 SC pulley upgrade is a substantially bigger jump as the stock V8 SC pulley is bigger than the stock V6 SC pulley.

 

That’s what I meant.

 

After checking the VAP site it seems I was wrong about "bigger jump on the V8 than on the V6 with smaller upper/SC pulley".
The VAP web page figures for lower/crank pulley vs dual pulleys plus tune are:
V6 - lower pulley plus tune 450 HP + 440 ft/lb, dual pulleys 475 HP + 470 ft/lb
V8 - lower pulley plus tune 645 HP + 597 ft/lb, dual pulleys 660 HP + 630 ft/lb
So a 25 HP/30 ft/lb bump for the extra (upper) pulley on the V6 but only a 15 HP/33 ft/lb bump for the V8.

 

So both our memories are failing. I plan to do only the lower pulley when I finally build my barn with a car lift, hopefully this year.

 

I did see a video of the upper pulley being changed on a V8 and the snout had to be machined to accept the smaller pulley (manual lathe that was attatched to the pulley shaft), whereas, the V6 has already been machined so it is an easier swap. As long as there are no ill effects from doing the upper pulley, I will most likely go that root as it's already apart so might as well.

 

Yep.
IMHO the lower pulley plus tune is plenty for a daily driver (as my F-Type is) and unless you are a boy racer / canyon carver / track regular the second pulley is not worth the extra expense and fitting risk/hassle.

 

Upper pulley made a wonderful difference on my V6. Best $300 I've invested in the car and more noticeable of an upgrade than the jump from stg 3 to 4. Install isn't bad with a med heavy impact wrench and the right removers. Can be done in a couple hours...

 

+1

Contrary to the horror stories of old about having to grind off the SC pulley and risk damage to the SC input shaft, I'd argue that swapping the SC pulley is an easier job than the crank pulley, if you have a suitable grooved pulley puller. No car lift required, no undertray to remove, no limited access to front of engine from underneath, no complicated belt run to deal with. You can do a SC pulley upgrade without a tune if you want to stage the upgrades, whereas a crankshaft pulley upgrade will require a tune as part of the package. I did a DIY SC pulley upgrade on my drive at home in little over an hour, see my previous post --> V6 SC Pulley Upgrade I fitted a 58mm Powerhouse Pulley (manufacturer for Viezu/Paramount), which gave a 6% SC overdrive and delivered 427bhp after tune. As stated above, the V6 supercharged snout is already machined, so no modification required. I wasn't after all out power, just a more punchy mid-range, so didn't feel the need to overboost the engine and take the SC to it's rev limit, where the efficiency drops off and you have to contend with increased IATs and heatsoak. Other factors such as long term effects of higher cylinder pressures and issues with aluminium crank pulley reliability (the Powerhouse SC pulley is made from Stainless Steel), all swayed me away from going down the crank pulley route.

@mattison If you are going to go down the combined crank/SC pulley upgrade route, you may want to consider upgrading the SC intercooler and SC intercooler pump to cope with intake temps.