Just got my new SC in - it's a V2 SC Trim.

Max RPM is 53,000

WIth the raised Rev-Limiter and a 6.25 Crank, that puts me at 56445.99 RPM on the impellar.

How dangerous is this?

IanS

 

Probably not too dangerous. I remember a long time ago when Matt got the really small pulley, he said that they told him it would be alright to overspin the blower for short periods of time, like a drag race. But he shouldn't spend extended time in the high RPM range overspinning the blower for a long time.

That's how I remembered it. I researched this for a while when I wanted a 2.87 pulley.

 

I'm sorry, can you please explain what you mean by 6.25 Crank?

 

6.25" diameter crank pulley diameter.

One of the factors you need to know to input for calculating impellar speed.

http://www.vortechsuperchargers.com/...pspeedv-2.html

 

What I don't get is that they say it's good for 20psi, yet you can't get more then 13-14psi before you're spinning it too fast.

 

Overtime even short overdrives will hurt it...trust me I know what i'm saying

 

That would be 13-14 psi measured at the manifold after losses through the intake piping. At the blower outlet it will be more, 20 psi if you believe Vortech.

 

Yikes! I figured .5psi drop from the filter and maybe 1-1.5psi from a CAI, but that leaves 5+psi just from the X-over pipe and TB?

Also, has anyone tapped the X-over pipe for a boost signal?

 

thanks

 

I'm going to use one of the blowers test port this weekend or later this week to see...

 

Well, post your results here....

 

That hard left turn immediately after exiting the blower has a lot to do with it, I have the feeling.

I drilled and tapped a test port in my blower outlet back in September, I need to hook a gauge up to it and do some tests, too.

 

You guys are missing the big thing...it's not the boost measured at the t.b. you gotta worry about killing the blower.

 

No, I'm going to keep them to myself.

 

We know. We're just hijacking Ian's thread.

 

so what is our status so far on overspinning the SC?

I take it no one is worried about it since you got the urchin ?

what boost are you seeing Ian?

 

Hit 12PSI once or twice, usually I'm hitting 11PSI. Then again, I'm still getting used to where the new redline is and usually shift well before it. So I think once I get my shifting down, 12PSI will be pretty normal.

Haven't Dyno Tuned yet (since I just got it all together and properly working last week).

But the blower seems to be taking the abuse without much issue. However- since I only drive on the weekends (I live and work in Downtown Seattle) - and it's been a short amount of time - I can't say much at all about overspinning it - except that it doesn't go KABOOM instantly when you go over the "limit" for RPM's on the blower.

 

BTW - I never did this. The smallest barbed hose fitting that Home Depot sold was a 1/4". IIRC the fittings in the blower outlet are 1/8", and I never bothered hunting for the correct fitting elsewhere.

 

I did. I never saw boost pressures above what I normally see inside the intake manifold, i.e. 10-11 psi, even after I disabled the bov so that it wouldn't release air when I closed the throttle after revving. I'm somewhat mystified about this. How does Vortech come up with that 20 psi number?

 

Interesting. Could it be the intake? Vortech's site says the SC flows up to 1000 CFM...IIRC the filters most of us use don't flow that much.

I'm amazed that there isn't a pressure drop of at least 1 or 2 psi between the blower and manifold.

 

There might have been. But not a 10 or even 5 psi difference. You make a good point about the filter. I need to redo the test with the filter removed.

 

I've Dynoed without a filter before - no HP difference.

But then again - I had my compressor leaking air, so that may skew results. (But it wasn't leaking 5psi or anything!)

 

I think the filters that most of us are using are 700CFM or so. Would flow enough for 20psi, but plenty for the 10-13psi that we get.

I can't imagine that is costing us 7+psi though...

We should ask Vortech.

 

When you dyno again, we should try that again, with the filter on and filter off to see if there is a difference, now that you have a blower that doesn't leak. Be a good test.

S

 

i thought i saw here that someone had a mustang trim blower on their max.
i wonder if other vortechs would bolt on to our plate

 

*bump*

Sorry for the old thread, but did we come to a conclusion on this?

 

On which part of it? Overspinning the blower or why Vortech says 20PSI?

As for overspinning the blower, I do it all the time - hitting 13PSI now that I'm used to the raised redline. Probalby shouldn't do it tho since I'm lean up top from the A32 MAF. <Never detonated once yet, knock on wood>. Had this blower almost a year now....no issues.

As for the 20PSI - I have no answers for ya.

 

I've thought about this a lot, and what I think is that the Vortech blowers are too big for a 3 liter engine, and we operate to the left of the surge limit line at high rpm. Efficiency goes to hell, and boost pressure never reaches what the blowers are capable of achieving if air flow was not impeded.

 

anyone know how to map out where we fall on this compressor map?

 

[QUOTE=JeffesonM]anyone know how to map out where we fall on this compressor map?


What size pulley and what is your fuel cut rpm?

 

no blower for me

I was hoping somebody with the know-how could plot out where the VQ30 falls on this map, similar to what somebody did for the VQ35 on the 350z forum...

 

By upgrading(via sending it to vortech) the trim on the supercharger wouldn't that solve the overspin problem

 

I've already did this for the VQ30, but I was working on turbo maps also for a BIG post and got lazy. IIRC, just shift them about 500rpm to the left...roughly.

I'll dig this one up and post it tonight.

 

They have a larger trim SC, however they won't trade/upgrade it with the Maxima smaller SC.

Somebody could buy the larger trim outright and then mod it probably.

 

BTW, that V2 SC map shows >70lbs/min of airflow is possible, which is enough to support over 700bhp.

 

I haven't called vortech yet, but you should be able to swap a sc or sq trim blower for the t trim blower which flows more air and has a higher rpm. its the swap I plan on making. Also my friend has a 4.6 liter stang with the t trim and he sees 10psi all the time. he has the vortech aftercooler and a 3.60 I think( i forget- i'll ask ) pulley any ways he wants to trade so thats my plan.

 

bump any updates? I was thinking about doing the same thing in the near future.

 

i have thought about this also...from what i remember from vortech's press release a few years ago the cost was $800+ for the t-trim impellar upgrade. basically the cost of a new blower.

i guess its just not feasable to drop $800 for whatever gains you would be getting.