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Hey everyone, looking for some advice please as im sure many here have experience on this.
I have a vortech v2 supercharger with a 3.4” pulley, 1000cc injectors, aem ems v2 Ecu and larger heat exchanger etc. the car made 398.8 @bub on its last tune on 14th of feb, then few days later I went to a dyno day next door, now I know different dynos different numbers etc before it gets said but the car on the first run made 393 @fly this time instead of hub, then second pull it made 340 and then he done a 3rd pull and it made 417, I will attach the graphs to show, at the end of the 3rd pull you can see it going up and down and my tuner said it was belt slip and when he tuned it he had to tighten it 3 times before the final figures he got. So my question is is should I be getting slip at this kinda power? And what are my options as to prevent it? Guessing there’s maybe a better pulley to use or belts etc.
Vortech kits arnt big over here in the uk and I have only ever seen 2 other s2000’s with them fitted here and they weren’t running as much hp.
Here is the graph when tuned and the one with the slip at the end
And one other thing as well please, my blow off valve is standard vortech is this ok for my setup? As it’s about 15 psi I think my tuner said. And since iv had the kit there has been an oil mist that gets blown onto my cross member cover that’s coming out of the blow off valve, guessing this isn’t normal? The charger seems fine with no shaft play etc.
Though power (or resistance of the impeller to rotate) does influence your likelihood for belt slip. I'd argue the size of your pulley, and hence its belt contact area play a larger role. At 3.4" you're not going to get as much belt contact as you need. From years of pouring over these forums, I'd say 3.8" is the lower limit for a 6 rib set up. You can always tighten the belt until you no longer get any slip, but that method can also result is destroying your main bearing prematurely.
3.4" is not only too small to prevent belt slip but it may be to small for the blower's own good. Have you checked your max RPM at the impeller at 9000 rpm? If it exceeds 55000 rpm then your blower will fail prematurely unless you have a high rpm capable trim.
If you want more power then rather go for a larger crank pulley and ditch the 3.4" blower pulley for a 3.8" at least or 4". That will bring prevent slip.
Oh by the way oil mist out of your BOV is unlikely but there's always a first for everything. If it is coming out the BOV then you are getting excessive oil through the impeller into the after cooler which would probably be from the valve cover vent. I bypassed that line running from the VC vent into the blower's intake to prevent oil getting sucked into the system but I never experienced what you are now. I ran a breather on the VC vent. That's one half of a typical catch can setup. Look into that if you don't have a catch can already. You should examine your blower's high pressure oil feed line to make sure oil isn't seeping out of it.
3.4" is not only too small to prevent belt slip but it may be to small for the blower's own good. Have you checked your max RPM at the impeller at 9000 rpm? If it exceeds 55000 rpm then your blower will fail prematurely unless you have a high rpm capable trim.
If you want more power then rather go for a larger crank pulley and ditch the 3.4" blower pulley for a 3.8" at least or 4". That will bring prevent slip.
not all true, he should be well into his blower's rpm range if he has the stock crank pulley and 3.4" blower pulley. Also if he were to change the crank pulley to a larger one, I would keep the 3.4" blower pulley. Through my experience on my own car the 3.4" blower pulley is the smallest you want to go before having uncontrollable belt slip.
not all true, he should be well into his blower's rpm range if he has the stock crank pulley and 3.4" blower pulley. Also if he were to change the crank pulley to a larger one, I would keep the 3.4" blower pulley. Through my experience on my own car the 3.4" blower pulley is the smallest you want to go before having uncontrollable belt slip.
I see. I've never gone below 4" so I did not get to test smaller pulleys personally like you have.
I see. I've never gone below 4" so I did not get to test smaller pulleys personally like you have.
with that being said, I will be increasing my 6.0 crank pulley to a 6.5-6.75 within this year while keeping my sc pulley 3.4. What I've noticed is if the belt is properly sized you don't need a whole lot of tension
Wrong. You want as long a belt as possible before you run out of adjustment headroom, to get as much belt wrap around the pulley for traction. A small belt will make things worse.
05-22-2018, 01:46 AM
Vortech belt slip advice and blow off valve.
