Super VXer
I'll get more in the specifics soon....
Well, add more to the Alpine/SC crap pile!
Found out I'm running a 4psi pulley, supposed to have a 5psi pulley!
....keeps get'n deeper folks, I'm calling Alpine, stay tuned....
This is where I got it done www.dynocomp.com
Last edited by jayfotos : 07/08/2004 at 12:03 PM
Draftsman of the dead
Super VXer
Super VXer
That's the tricky part, it's supposed to be 52mm for a 5psi....53mm for a 4psi.
A tape measure won't cut it and Alpine told me to measure from the threads, so I would have to pull off the belt?.....come'on, I can't do that....no tools.
Super VXer
Hp and torque dyno chart
Super VXer
Here is Anita Dyno'd with just the catback...
Humm wonder what is up?
VXer
Something doesn't look right. I certainly hope all of us with superchargers didn't invest $4,000+ to dyno out at 185 HP compared to a VX with just a cat back system (Anita's) that dyno'd at 188.7 HP. I'm no dyno expert, but either the dyno report on Anita's VX is not correct or the one you just had done is not right.
Super VXer
To help better understand, this is a 4WD dyno, not rear wheel.
Super VXer
....... no surprise ......
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of course Anita(s) is hot !
.
.
two different dynos ....... runs on different days ....... etc etc ...
Super VXer
Alpine is certain that there is a 5psi pulley on my kit. Now, is there any mistaking that there is 5psi pulley on there?
I repetely asked the Dynocomp guys if there was any way that why it's not running at 5psi...."sure, your running a 4psi pully.".....are you positive? "positive".
Alpine can't believe that.
So, I think I have to pull off the belt and get it measured by my shop on top of my cone being either replaced or resealed(witch they still have no answer for me on that).
Is it me, am I nuts? Or is this a huge pain in the ***?
Super VXer
Sound to me like it a pain in the arse. Sorry your having so much trouble with your SC, mine has been trouble free.
I hope that the shop can fix/seal the problem or that Alpine will pony up. I felt a nice difference when I switched to 5 lb pulley, hope it was not all in my head, as my boost gauge reads 5 psi when I am in boost.
How is the truck running? Have you gotten on it? Does it feel faster to you?
Good Luck.
-Dave
Super VXer
one thing you need to know about dynos. they use a correction factor (for temp. humidity. etc) . you can make it say whatever you want. by using a different correction factor. shawn
1COOLVX
Super VXer
Holy bageebiz, Alpine called me back!
They are sending me a new nose cone assembly with a new pulley, oil, sealent and a fuel line.
I asked them to please double check on the size of the pulley before they send it out. Thing is, I have to pay to install it....again.
autox-racer- put in your gauge and see what your push'n and if you got the time measure your pulley and see if it's 52mm or 2.05 inches from the "ribs" of the pulley. I'm curious to see what you come up with.
Cyrk- I do notice a big difference in performance(a lot more when it's cooler), but if I have the wrong pulley, that 15-20 extra horses would make a biger difference. Did you have the guage with the 4psi pulley and did the guage show it at 4psi?
VXer in the Sky
Tell us how your shop (hope they are better than the installers who told you rich would blow the motor) determined you are at 4 psi? Gauge? Where did they tap it? Depending on where, you will get different readings.
And are you running rich or lean? What is your fuel pressure? What plugs are you running? What correction facgtor did they use?
Measuring is simple and ouside diameter of the overall pulley will only get you in the ballpark - measure where the belt rides with calipers - yes it is BIG hassle to loosen the belt. . If ya'll can't tell a difference with the SC installed there is a problem with the NBTW. And if you didn't dyno before you installed and then again right after, you have NO room to whine. When a blown VX walks a stock one at the track or on the street, what would you say accounts for that? It ain't gonna be LESS HP!
And BTW, in 2WD, a min of 20% power is lost in the driveline to the rear wheels - in 4WD there is even more loss. A before and after would have shown the overall increase after making a single change. I ask John to call you so you'd chill - guess it didn't help.
Super VXer
From where I saw them test the boost they put a line what looked like behind the SC, it was detremind by the computer(see chart above) that's what they showed me to say I was running at 4psi.
My fuel/air was perfect(see chart above) and that was my main concern, they reassurded me I was running fine.
Plugs- stock and if you have a suggestion on replacements, I'm on it.
correction factor- don't know.
They told me there is close to a 40% loss in power in the 4wd drivetrain and the TOD did'nt help. What they were most impressed was the tourqe and one of the guys there compared it to his Trooper 3.2L and he was impressed with the overall performance and wants a SC for it.
I'm not complaining about any of the performance, it's got bigger balls now. I just want it running at peak and seeing it at 4psi pissed me off....there's 15-20hp that's supposed to be there at 5psi.....if that's the case.
When I get my new cone and pulley I'm going to measure the two pulleys and see, at that point we will really know and I'll dyno it again.
I am chill, I've spoken with John(Alpine) and told him my concerns polightly....but I don't like being left in the dark....that's what really pisses me off. Thankfully, I have you guys here to buffer that and I'm learning a lot and I hope you guys will learn from this as well. I'm giving blow by blow comintary of everything I'm going though hoping that if anyone runs into these same problems you'll be a bit more prepared than I was.
Super VXer
I'm a little weirded out by this dyno chart, is the rpm supposed to decrease after 3500rpm then slowly rise?
Watching the dynocomp guys, it was a steady rise on acceleration threw each run(4-5 runs)...are there different ways of running a dyno test?
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