I just called Vortech asking about upgrades from the S-Trim and he said I could upgrade to the Si-Trim (http://www.vortechsuperchargers.com/product.php?p=3) where you send your unit in and they put a new impeller on it. He said it's good for 775 hp. (S-trim rated to 680) A big difference from just a new impeller hey. I don't know a price, but I'm guessing around $500. Vortech I think is good about repairing or upgrading their stuff because I rebuilt the S-trim on my own and just the bearings cost $300, when their price to rebuild was $300. The T-Trim would be about $2150 if I trade in my S-Trim. Because of the price, I would just get the impeller upgrade, except I do not want to top out again. My vehicle has 8.75 ratio, intercooler, 229:242, 114 LSA cam, and soon to be methanol, so it can handle quite a bit more than the 11psi I have on it now.

Has anyone heard of or installed the Si trim, and what do you think?

 

I would step it up even further, and go Ysi

 

I would think about it except that almost all I've done is work on this car since I bought it, so now I just want to plug the upgrade on and go.

 

I'd say the YSi also with those kinda cubes, although it wouldn't exactly be a plug and play. Would need to make some minor changes. I'm doing that upgrade now from my T-trim. The T-trim ran good on my 383, but i just wanted more. If your dead set on a T, i'm getting ready to put my head unit up for sale on ebay if i didn't sell it local or on here 1st. Just about done with my upgrade project. There's about 8k miles on it, no leaking and tight. But again, give a 2nd though to bigger, and if not, shoot me a message.

Ken R.

 

You're getting 11#'s from an S-trim on a 396 with an intercooler? How?

Chas

 

Now would be a good time to look into a turbo kit. I was sort of in the same boat when I decided to switch.

Consider the $2150 you are prepared to spend plus selling your complete blower kit, headers, y-pipe. You could actually go turbo for cheaper than upgrading to a T-trim.

Just a thought.

-Scott.

 

I get 11 psi because I have an undersize pulley on there so it's spinning faster than Vortech specs. Vortech's max RPM for the S-trim is 50,000 I think, but at 6 grand mine is at about 55,000 if I remember right.
I've also looked at turbos quite a bit, but it's really not that easy. (I actually have a turbo right now that I never hooked up from an abandoned project.) I also wouldn't change now when I'm tired of working instead of driving, and I already have the blower, so I'm going to stick with it.
Apparently the Si upgrade is pretty new since no one has mentioned it and there aren't any search results here on it. I'll call Vortech Monday and post what price they give me. Also I hate to say this here, but for Vortech info, I found in the past that 5.0 Mustang forums have the most material. That's the only place I found instructions on how to rebuild an S-Trim.

 

cause when i was looking at FI, i found procharger to be much more helpful with questions and such than vortech. And a lot more info about procharged LT1s than vortech

 

LJ several years ago went 9.9X with a S-trim in a full weight camaro.
But with bigger blowers its easier to make power.

 

you have lots of cubes for an s trim, even for a t trim,

I would really consider a t or ysi trim to feed that big motor.

 

Subscribing...

I'm in a similar boat. I built a low compression 396 later last year, and just bolted up the ol' A-trim I had just to get me going. The A-trim is maxed out and I see 4-5psi with 160 IAT's (in 80+ degree weather at the track) injecting meth w/no IC. For about the past year my plan was to just keep my eye's peeled and pick-up a T-Trim headunit when a good deal comes up.

Well, it's been over a year and I've seen a handful of headunits, but all of them have the wrong housing or rotation, etc etc...

I'm not trying to hi-jack your thread...just curious to see what you find. I've been out of the loop for a while, primarily since my car hasn't broke anything major in about year *knocks on wood*

But I've been itching to raise boost for farrrr tooooo long now.

 

What T/A Kid said.

LJ was going 9.9 at 139-140 mph on an S-trim. I had a very similar combo with a T-trim, but only managed 10.40 at 133 mph with 3 more psi boost. I'm not sure why his was so much faster, but its clear the T didn't give me a big advantage over his S.

 

hmm...I just referenced an old Vortech Performance Matrix I had saved from a couple years ago. The max CFM of the V-1 (or V-2) s-trim is 1000cfm vs the V-1 T-trim at 1200cfm. 20% sounds like a significant difference on paper...

Maybe I missed it in an earlier post, but can anyone chime in who's swapped from an S-trim to a T-trim? I'd be curious to hear real world results attributed to the change. Thanks.

Also, I ran into this chart:

 

I've gone from S trim to T trim on a non intercooled setup with a pretty basic 396.

When I had the S trim on it was maxed at 10 psi with a 2.75-6.66 combo around 6100rpms. Best 1/4 with a 6speed land barge (3850lbs) was 10.83@134. Dynoed around 560 3 years before I ran that time. Lots of tweaking and tuning between with the alky. Still saw real high IATs in the 190 deg range.

Fast forward to 07 and got a T trim from ebay. With the same pulley combo I was seeing 11psi and ran a 10.68@133 and had a best mph that day of 137. No real useful dyno numbers I had been using a custom 7.2 pulley and always had belt slip. It made 565 on the dyno with slip.

Now it has a 7.4 on there and it has been all bad luck. It blew a head gasket at 17psi at 6600. I keep the revs down to 6100 and it is at 14psi (no belt slip) with high IATs again even with a dual nozzle kit. I have not got a chance to get the drag rims on and make a real pass as the meth had a malfunction and I thought I killed the motor while testing this summer. That is another story but I'll make a post on it as I am ultra stumped on what is going on now with the motor.

So an S trim can make good jam with a 396 if you spin it. It is sitting in the garage. Maybe I should get some new guts for it.

 

That's really interesting information. I also said I would post the prices from Vortech.

-To upgrade an S-trim to a T-trim: $1100 (bearings, seals, impeller, impeller housing)
-Just the impeller and impeller housing would be about $800.
-What sucks is that my S-trim serial number makes it a model too early for them to be able to do the upgrade. They said they had tried it on a couple units, but didn't let them leave the shop because it didn't work out.
-The Si-Trim upgrade is $655 (new bearings, seals, impeller, impeller housing) but they would recommend a T-trim upgrade over this one, and they can't do this upgrade to my unit either. (Si-trim rated to 785 hp, T-trim rated to 850)

-If you rebuild your head unit, send it to Vortech. I rebuilt my S-trim and just the parts were about $350, and I called several places, when Vortech I think wanted $320 or so to rebuild it. (The two matched high speed bearings were $280.) I would just include a note on the unit begging them not to tear all the threads out of the aluminum housing since someone did that to mine and I had to helicoil about 5 holes.