Skunkworks

I’d say yes, because the YSi will be softer (less boost) at lower RPM range than a T-trim on your stock engine. This is because of non-linear (more exponential) nature of centrifugal compressors. 3.6” pulley would likely be a decent starting point, disk maybe 4” OD and 3.25” ID, it’s easier to open it up or remove metal than add.

Just remember you will be putting more HP into blower when using restrictor disk, than not, it’s about finding a compromise that nets you better low RPM response, while not pushing impeller too far off design. Temperature is a good indication of efficiency, anything above ideal rise is wasted energy (HP required to turn it).

Good luck.

Arun@Dasilvamotorsports

The YSi is real lazy down low, it likes to spun hard. I think you will be greatly disapointed with the YSi over the T or Ti trim, unless you put a 2.75" blower pulley on it.

You might want to consider a JT or a 2200?

WickedVetteLT4

Skunkworks... I appreciate all of your knowledge and help bud! You've cleared up some things for me just with the couple posts you've made. So a 3.6" pulley with a restrictor plate would be a solid starting point and then just play with the opening on the plate until i get it where i need it? I guess I need a big enough difference between the pulley size and restrictor plate size to have a noticeable difference in boost with and without the plate to make increase the torque but not too big of a difference to where the impeller isn't working efficiently.

Arun... That is exactly what concerns me about running the YSi setup. Maybe the Ti is the better choice?? I do plan to build the block in the future like i said but that could be 6-8 months away. I'll have to look up peak power difference between the Ti and the YSi and if the Ti can spin hard enough to get me close to my goal, that might be the happy medium for now and later as opposed to running weak now until it runs nasty later with the YSi. JT wont work on a vette from what im told. Its opposite rotation only. Only choices are Ti and YSi now if going vortech. 2200 would be an option but i was trying to stay vortech if possible.


JESUS! IM MORE INDECISIVE THAN A FEMALE! LOL So many factors to consider i don't know which is really the better route to go.

~Self contained VS. oil fed.
~I already have the YSi VS. selling it and getting the Ti.
~YSi is louder which i like VS. the Ti is more quiet.
~Ti will make better power now VS. YSi will make better power later.
~Etc.

lt1z

I'm with Arun. A 2200 or JT may be a better middle ground option to run now and later since it falls in-between the Ti (1300 ccm) and YSi (1500 ccm). The 2200 is available self contained and the JT is not. The Ti is a newer more efficient design then the JT though so the difference may not be much and the Ti will win out down low.

Skunkworks

I wouldn’t be afraid of a Novi 2200, if you have a new YSi (never installed) then maybe Doug @ ECS can work out a trade for you?

My suggestion on pulley and restrictor disk sizes are safe starting point, you can go more aggressive, but not too much. Wouldn’t do a 3.25” pulley as an example, you could actually loose boost in some regions and have very high IAT’s.

With the YSi on stock block, I'd personally do a restrictor disk if it was my car, but not go crazy. The benefits outweigh losses (more HP to turn it), if done correctly.

Silver Bullet C6

I hate to be the "wet blanket" here but are you sure you want to put 800+ WHP behind a 6L80 ?
It's one thing to make the HP, but I can tell you from experience once the A6 starts to give you problems it's a big headache (left me stranded a few times). A stalled, geared A6 at 750 whp would be VERY fast for the streets and your A6 may live a little.

I've switched to a Powerglide and am now just waiting for the tuning to get done. Best of luck to you on which ever way you go with your car.

DSteck

Its a T-trim.

SteveDoten

I'm just going to dupe my previous post, Josh built the car and it ran 9.5 w/ a T-trim.

I wouldn't tell Megan Fox to change her gym routine?

Whatever you end up doing, have fun with the build, you'll learn something; only a handful of Ysi monsters out there

algZO6

i love my t-trim but wouldn't mind stepping it up a bit. i would jump to a 2200 given the chance even on my stock bottom end. here are a couple of vids. this is on a stock bottom end ls6 with a od crank pulley and a 3.125 blower pulley in 6400' DA.

WickedVetteLT4

I've tried to reply 3 times now to everyone individually in one response but my phone keeps messing up and freezing causing everything ive typed to be deleted. Ill have to address the individual posts when I get back to a computer.

*** UPDATE HOWEVER***

I received a call today that my original T-trim will be repairable afterall. So... Looks like ill be getting it back fully rebuilt in a week or so. Should it all work out as planned, ill slap it back on the car and either hold onto the YSi for the big build or just sell it and worry about all of that later on. Either way, as long as the t-trim is good to go, it'll save me some money and I can keep running the car as is and have that much more toward the setup I really want.

Lets just hope it all works out that way. Lol