Ok, so long story short...I've recently acquired a complete Vortech V-1 kit for 93-97 Lt1 F-body...anywho, it is used, claimed to be less than 1000 miles, everything looks brand freakin' new so I'm not questioning mileage...The deal was, I bought this kit off a shop that installed/removed it from a customer's car that did not like the power increase/mileage drop. Trim was not given, pulley size was not given, but I got the kit for the price of labor the kid owed the shop,so even if it ended up being an A-trim I would be getting a steal.

Questions: First off, I'm trying to designate weather or not this is an S-Trim or T-Trim V-1. According to the dimensions I've been looking at the very inside diameter of the inlet for an A-trim = 2.5", S/SC-Trim = 3.10", T-Trim = 3.29"

Measuring the very inside of my inlet a safe measurement (if anything too small) is 3 3/16's inches...this is inbetween S and T-trim dimensions...Keep in mind, I'm emailing the shop, but have yet to recieve word back, so I'm curious about your guys input. Anyhow, another weird thing, all other pictures I've seen of S and T-trims the impeller only has 8 blades, mine has 12. Next, I read the current thread someone started in regards to pulley size and boost output. My crank pulley measures approx. 7 inches....the pulley mounted to my headunit (inner rib measurement) is lil' under 3 inches...(outside rim measuerment) approx 3.5 inches. So, if the Crank is 7inch, and the head unit is the 2.90inch according to that thread will produce 10-12 psi.

I searched for somewhere I could enter my Serial Numbers, couldn't find anywhere...I'm assuming to get direct answers I'm going to have to call Vortech.

I'm trying to get this all figured out, in 2 weeks I'm pulling heads, installing ARP head studs, Hooker LT's, Crane Ignition, 10.4mm wires, AR 103's, 42 lb injectors, Fel-Pro 1074's, this supercharger kit, and some other goodies, then trailoring it all to a dyno and having it tuned.

If you guys have any input on this, or where I should go/talk to figure this out, that'd be great.

My other question is, how detrimental would it be to vent already metered air through the bypass valve to atmosphere with this setup? I realize it will cause a rich condition, but have never heard how much it actually effects the engine. If its bad enough, I will just modify the MAF housing and Intake tubing and move the maf back to the stock location. Are there any adverse effects running our MAF's blow-through? as opposed to suck through?

This post is big...I'll stop now, I have lots of questions...

Thanks ahead of time,

BTW: I have part numbers, and pictures if it'll help...

 

One way to tell for sure on the trim: measure the OD of the compressor inlet hose connection. 3.5" = S-trim. 3.75" = T-trim. It should also have a metal tag on it with the trim.

If you run the MAF on the inlet of the S/C, then you have to run the bypass valve back into the piping. It stays open all the time, except full throttle. You can run it blow-through, but you have to tune it accordingly.

Mike

 

Ok, so it's an S-trim for sure...3.5inch outter diameter for the hose connection.

There's a metal tag, all it says under model# is: V-1 then there's a serial # below that, then there's a Carb EO# that is left blank...

Far as tuning for blow-through, I'm assuming any dyno tune shop should be capable of doing this...speaking of which, this is perhaps more appropriate elsewhere on the board, but anyone recommend a tuner in the Pacific North West U.S.? more specifically Ellensburg, its near Seattle...I'm looking for a quality place to go to, willing to drive as far as Portland...all the local shops 'round here and Yakima have crappy reputations, and do some shady stuff...

 

My A-Trim had the metal tag that stated V-1 , a low serial # of 01741 ?
And no CARB EO#. I called Vortech and they verified that it was the A-Trim - he asked me if the inlet blades were straight or angled. Anyways , They sent me a CARB EO# sticker for the head unit - my A-Trim had 12 blades. My S-Trim has 8 blades.
Dennis

 

hmm...crap...well mine definately has 12 blades, that are straight...I'm going to call vortech to clearify exactly what boost these pullies are set for, etc...but after doing a google image search, I'm pretty positive this is an A-Trim. After searching, I havn't been able to locate specs for the A-trim...far as CFM, Max impeller speed, hp, etc...so if any of you guys have a link, or know these off the top of your head that'd be great...

Couple more questions concerning MAF placement, and venting to atmosphere.

MAF: If I do blow through, is there a minimum distance I must keep the maf from the throttle blades?

Venting to atmosphere: I have access to an adjustable Tial BOV. I can adjust for how much vacuum it requires before it opens, so theoretically if I adjusted it so it only opens at or near max vacuum (no throttle, or going from full to no throttle) I would only be facing the rich conditions issue at idle/low throttle when there was enough vacuum to actually open the valve, correct? I'm new to all this, just trying to think this out logically.

Also, at what RPM do these s/c start to build boost? for my purposes I'm just curious if I'll still be running vacuum at low rpm/throttle levels cruising around town.

Thanks,

 

Try Blood Enterprises in Auburn.

http://www.bloodenterprises.com/menu.htm

Mark or Craig

 

My V-1 gets a little bit of boost as soon as you punch it. You will not see any boost cruising around town, only when you hit it and the throttle blades open will your engine see boost. All other times you will be in the vacuum.

 

Ok, thanks for all the help, this is all getting pieced together....

Question concerning use of FMU: It's my understanding the FMU raises fuel rail pressure along with boost to over-run the stock injectors allowing you to run these kits on a stock setup. Since I'm using 42lb Bosch injectors, it seems with proper tuning I would not need to use the FMU for the kind of boost/power I will be making. Is this right or wrong? It'll just make one less thing clutering up my engine bay if I can toss it...Also, how does the T-REX inline pump effect the overall fuel system? Will this pump alone over-run the stock regulator and will I be running higher fuel-rail pressure regardless?

still trying to tie-up some lose ends, Thanks,

 

With 42# injectors and proper tuning, you don't need the FMU.

The T-Rex inline pump will not over-run the stock regulator.

 

Here is your A-Trim performance data:


http://web.archive.org/web/200302012...rformance.html




You will build boost only when under a hard load. The bypass will close as manifold gauge-pressure approaches zero, at which point the blower begins to pressurize the intake.

-Scott.

 

No FMU it is...nice...

Well, I guess initially I'm going to tinker with the Tial BOV...I'm assuming Vortech has their cheap looking by-pass valve only close when vacuum is at or near zero is so this setup works on stock cars, not requiring any tuning. Perhaps adjusting this BOV to close unless at MAX vacuum will result in a broader power gain. No peak gains, but maybe I'll make more power sooner do to their being boost present earlier...not sure if this thinking is correct...

damn....hp range, and CFM go through the crapper when you go to an A-Trim...that lowers my expectations of this setup...

meh, I guess all I can do is run it for now, plan to upgrade near future if this doesn't pan out like I had expected...

Thanks again for the help...

 

I would suggest driving it to max rpm if you can. Expect 4-5 psi.

There is no power in the bypass valve. Just let it do what its designed to. As soon as you go wide open it will be shut.

 

I have an A-trim on my car with at least 30K miles on it and I see 5psi with ported heads, cam.....

Check out the exchange program Vortech offers if you haven't already.

http://www.vortechsuperchargers.com/...1.asp#exchange

http://www.vortechsuperchargers.com/...exprogv-1.html

-Scott.