It all depends on how much boost you want to make and what you have to support it.

If you intend to spin the SC faster than you do with the 9lb pulley, you should definitely look at getting the 928 impeller.

Things that you can do with pulleys:
Get an even smaller pulley to place where the Stillen "high boost" pulley is.
Get a larger SC-side jackshaft pulley
Get a smaller SC-side SC pulley
Any combination of the above

Keep in mind that changing the SC-side pulleys may require you to get a larger idler pulley.

Actually, if you plan to spin the V3 faster than it's max rpm of 52000 then you should get the 928 ceramic bearings. The Si impeller is just fine. Mine actually started making boost sooner than the 928. I ran both on the dyno.

I am deciding if I want to switch from my 8 lb pulley to the 9 lb pulley I have . Just not sure I want to go thru all pain in the *** of more remote tuning again. I really hate that.

Great feedback from everyone...TY Gents... I also forgot to mention that I have TBatts idler pulley/belt upgrade. Hoping that helps keep things down. I am also like Redondoaveb and using the turbo guard with no filter.

Are the spacers needed for the upgrade @redondoaveb for the jackshaft/SC pulley upgrades? Its been a minute since I’ve been on the forums but I also recall ur set up having the fabricated wastegate to the charge pipe. I recalled u referring me to Alex with L-Spec up in Hawthorne. I also reached out to Seb since he’s the one that has tuned my Z and was working/tuning ur Z at the time and he mentioned they (Specialty Z) were considering fabricating the piping and wastegate set up for open sell to others like myself....but not sure if that ever materialized or not. I also emailed Alex but last I heard they were working on a putting a pricing group together but received no other update since that time which was about almost a year ago. LOL

If the wastegate upgrade isn’t available then I won’t be going for boost anywhere in ur range... @redondoaveb. Don’t think it would be feasible for me without that and a boost controller as I am on a stock block with stock internals ...I’m using the CJM S1-SE set up what the 485 Walbro pump/CJM Top hat 1000cc Bosch Injectors for plumbing but unfortunately my fuel options are limited. The weather out here in the West Pacific doesn’t work well with E-85 or any flex type fuel due to our humidity. 91 at the pump is the highest we get with the exception of course of VP MS109 from our local race shop that ships that good stuff in. But at $120 for a five gallon can...we save that strictly for track days/money race events...Lol. We do have great sunny weather year round and nice white sandy beaches though LOL!!!!! Give and take I guess... Oh well...:tup:

Since a little more has been shared on my set up any great advise from those of u with the experience here would be greatly appreciated. Thank you for laying down the groundwork for improving this kit. If it wasn’t for TopGunz and guys like you on this forum we would all be stuck with the basic Stillen Kit.

If 91 is the only fuel you're going to run then the wastegate wouldn't be needed. You can run around 13 psi on 91 before knock. If you plan on boosting above that level by using a higher octane fuel then you would need the wastgate in order to dump excess boost when you're running 91. I bet if you contacted Seb, he would be able to build you a custom set up like he did with me.

Sounds like a great idea....I’ll reach out to him before we send the charger out to 928. Thanks again Pat. If the waste gate doesn’t happen what pulleys would I need to change out to get up to 13psi? I’m currently at about 8 to 8.3psi with the 9lb SC pulley that Stillen sent me which is on the Jack-Serp side. This low boost has tk die wit my location, weather and sea level factors

I used the 9lb and a 2.85 supercharger pulley to get to 13 psi (12.86 to be exact). You'll have to go to a 3.00 idler on the supercharger side if you go with the 2.85.

Awesome... Will these pulley changes require the spacers mentioned by Cupcakez? I know it was mentioned earlier On the thread I believe by by imazman that it was a pretty tight fit on the idler pulley (SC Side).

Remember that your SC will not come with a warranty if you send it to 928. If you send it to Vortech and get the Si impeller then it does come with a warranty.

As long as you do not change the jackshaft pulley on the supercharger side, you won't need the spacers. You may need the RPM belt instead if your goal is 13psi and you put the filter on, depending on the belt tension and impeller.

Good point. It's too bad Vortech won't do ceramic bearings in the V3 though.

As mentioned by"Z"en, you won't need spacers unless you change the jackshaft pulley, sc side. Also, the idler wasn't a tight fit at all. No issues using the 3" idler.

This was my next question.

Mine is Vortech Si with ceramic bearings (928 internal). :D