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Discussion Starter · #1 ·
Good evening everyone,

I've been trying to do some research on how to squeeze more out of my V-2... thus far I've seemed to hit a wall.

It currently seems as though I'm running the max RPM for my V-2 with a 32T jack shaft pulley, 28T S/C pulley, and 5% OD ATI crank pulley. It's netting my around 8.3 psi with that setup, but I also just found that my o-ring came out and my diaphragm was ripped on my Vortech Maxflow valve, so that may help me pick up some more boost (no clue what my setup should be hitting).

Does anyone overspin these blowers to 58k RPMs? I've read about many other vehicles doing that, but has anyone on one of these? I'm working on seeing if there's anything I can do through Vortech to beef up the blower so that I can feel assured it can handle the extra 10% I want to put to it, but I'm not sure if there's anything there or not?

Any input/real world advice is appreciated. If it can't handle it, I guess I won't do it... it'll just encourage me to move on to a new power adder more quickly - though I can't believe the ceiling is so low on these.

Thanks for your assistance!
Trevor
 

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Trevor, your already past the operating range that your blower was designed for if your 4k over recommended maximum rpms. It might explain why your IAT's are higher than expected at higher rpms ass well. You might have to move up to a bigger blower ie. V7 Ysi bc your present blower is maxed out. I think the V7 Ysi has the same external dimensions as the V2, based on what I see on the Vortech site, but I'm not sure. Maybe Brian (BJB) or someone else can chime in that has a 7L motor with that blower on their Jeep.
 

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what other mods you have? heads,cam,stroker??? seems kinda low for the pully combo! I peaked 10 psi on a 30t only
 

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Discussion Starter · #6 ·
I think I do have some pressure to regain by having a properly functioning bypass valve. Once I receive the pieces for that and get it set up I'm expecting to potentially see a little bit more boost. I still am baffled at how "low" these things are maxing out? I can't understand how at least 14-15psi shouldn't be feasible regularly with them? Am I missing something?
 

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I'd replace that bypass valve & see where you are at! if its still low maybe belt slip! IIRC keoni got around 13 psi I think with almost the same pully set up as you when he had his 392 & v2 I know you have a little larger engine but my guess is at least 10 psi on your set up!
 

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I think I do have some pressure to regain by having a properly functioning bypass valve. Once I receive the pieces for that and get it set up I'm expecting to potentially see a little bit more boost. I still am baffled at how "low" these things are maxing out? I can't understand how at least 14-15psi shouldn't be feasible regularly with them? Am I missing something?
I picked up almost a full pound of boost when I replaced a leaking BOV with the same problems that you have. The BOV should help for sure but I think the V2 and V3 blowers are designed for stock displacement motors not 7L strokers. I'm making between 8.5 and 9lbs with the stock 32 tooth pulley set up, but I have a blower spec'd cam not the stocker. I'm not really sure about the blowers with the stroker motores hopefully someone can give you some information on this.
 

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I was building # 4GR032-034 34 Tooth Count Jackshaft Pulley and # 4GR033-028 28 Tooth Count Supercharger Pulley plus 17% overdrive crankshaft pulley. A total of 15psi boost, 640rwhp on strong 6.1L.
 

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Discussion Starter · #12 ·
I was building # 4GR032-034 34 Tooth Count Jackshaft Pulley and # 4GR033-028 28 Tooth Count Supercharger Pulley plus 17% overdrive crankshaft pulley. A total of 15psi boost, 640rwhp on strong 6.1L.
From what I get - that gives a total compressor wheel RPM of 65362.96 at 6,600 RPMs. The V-2 is rated at 52,000 RPMs. That's equivalent to 126% of the max rated RPM - so obviously 26% over-spun.

How long have you had the Jeep that way? Did you do anything particular to your V-2 before spinning it that high?
 

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My a red line on 6200rpm, maximum power on 5500rpm.
I'm not saying that I did well, but was a prototype version. Now I would not use the 17% crankshaft balancer.
 

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Discussion Starter · #14 ·
My a red line on 6200rpm, maximum power on 5500rpm.
I'm not saying that I did well, but was a prototype version. Now I would not use the 17% crankshaft balancer.
Did you ever have any issues at that level? You spinning to 6200 RPM would still net a higher head speed than what I'm thinking of doing because of the crank pulley. Though I won't be lowering my redline down from 6500-6600 anytime too soon I don't think.

Does anyone know if there's anything you can do to upgrade the bearings so that it won't fail spinning the head unit at those speeds? I'm not too worried about the fact it will eventually throw lava out of the compressor housing - I can manage that (already sort of need to). I'm only concerned about catastrophic failure of the head unit.
 

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Discussion Starter · #16 ·
they Make better ceramic coated bearings rated at higher rpm

Sent from AutoGuide.com Free App
They being Vortech specifically or they as in... they exist? Vortech mentioned something about a T-Trim upgrade with a better bearing (maybe 55,000 RPMs?), but it seemed like the juice wasn't worth the squeeze.

If going to a ceramic bearing and sticking with the same oiling as it currently has will give me the opportunity to really push this blower then I'll have to really consider it. I doubt I'll have Vortech take care of the work as I know plenty of machinists locally who rebuild things that spin much faster than 60,000 RPMs.
 

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when I bought my vortex rebuild kit from a reputable online site ..they offered a upgraded ceramic coated bearings that was rated at a higher rpm then the standard bearings that the v3 uses.talk to your friend..he should know.

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Discussion Starter · #18 ·
when I bought my vortex rebuild kit from a reputable online site ..they offered a upgraded ceramic coated bearings that was rated at a higher rpm then the standard bearings that the v3 uses.talk to your friend..he should know.

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Any additional info on this? What kit? What are the bearings rated to? Etc... I'd like to look into this... Thanks!
 

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Discussion Starter · #20 ·
PM sent! regular kit was rated at 59k rpm & the upgraded kit was rated at 62k rpm
Thanks for the information - very informative!

So you're running a V3 kit then? What pullies are you running?

If my calculations are correct, if one is running a 5% OD ATI pulley, 28T S/C pulley, 34T jack-shaft pulley, standard jack-shaft serp pulley (3.33" IIRC), and shifting at 6,600 rpms then the impeller speed would be 58,852. That would suggest that even the "regular" rebuild kit would be sufficient to make a decent bit more power as compared to the "normal" Vortech specs? Though there's probably something to be said for the ceramic bearings even running below 59,000.

As far as I'm aware of "off the shelf" parts the only other thing you could easily do would be to go to a 17% OD ATI pulley, 28T, 34T, 6,600 RPMs - this would net you at 65,363. That would put anyone outside of even the ceramic bearings tolerance.

So basically a maximized setup would be something like a 5% OD ATI, 28T, 34T, 3.17" jack-shaft serp pulley (I just made that up - don't know if they exist), and shifting at 6,600 RPMs - which would give you 61879. Another option may be something like a stock crank pulley (6.44" I think?) with 28T, 34T, and 3.01" jack-shaft serp pulley (made up again) to net 61900. And what may be the "best" option would be something like an ATI 13% UD crank pulley, 28T, 34T, and 2.57" jack-shaft serp pulley (author's license take 3)- this would net you the benefits of an underdriven crank pulley (i.e. less spinning of accessories) while still giving you the same head speed; which I would think in theory to produce the most power and airflow combo?

No matter what these combos, It'll probably throw lava, but within some reason that can be combated. That would be just about everything and the kitchen sink at that series of blower.

Does anyone ever do a V7 YSi wheel in a V2/V3 housing? I'm not sure if the housing has sufficient casting to support that diameter or not, but just figured I'd ask.
 
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