vortech FAQ: read this before asking vortech questions
so its safe to just change the pulley on a stock kit? safe on the blower i mean... im looking for 420hp ...gets installed this week.....have utec, 440cc, evo2 exhaust, and 5/8" spacer... figure im looking at maybe 380 tops with a great tune....probably going to do meth injection for sure.... i got alot of friends with it on their evos....anyways can i just get the 3.12 pulley and be safe?
If youve upgraded your fuel you might as well go to a 2.87. Way more fun. You'll need to retune but you'll be safe. 420whp is a big goal but you can probably reach 400 and be happy with it.
whats the break down on boost per pulley? because I got a used kit and I was told I had the 2.87 pulley and I was boosting 13.5 psi. is that normal? because I really dont want more than about 8 or 9.
so i can get the 2.87 pulley and be good? just was told by a member on g35driver that by changing my pulley size will cuz my blower impeller to go to fast and that id have to upgrade my blower bearings? is that just a bunch of bs? if so i ordering the 2.87 pulley now
so is it even worth the difference in the 2.87 and the 3.12? at 3.12 i can still go to 6800-7k rpms safely on the blower? wouldnt that make more power going higher in the rpms w/vortech
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From: phoenix, AZ
I just posted this in another thread and will just copy/paste it here:
Originally Posted by sentry65
I don't recommend 7k rpms with the vortech on a non-revup motor.
7k rpms and 3.12 pulley is putting the vortech blower to it's recommended rpm limit, but if you're going to do that, I'd rather do the 2.87 pulley and a 6500-6600 rpm redline and get more torque which the vortech can use more of.
The peak hp will be close to the same anyway. For instance:
400whp and 300 tq @ 7000 rpms and with the 3.12 pulley
vs
400whp and 323 tq @ 6500 rpms with the 2.87 pulley
the fuel requirements are going to be about the same
The engine will make more tq which IMO is easier on the engine than going beyond redline, the engine getting even hotter from the rpms, and still having to deal with 400 whp on top of that. Not to mention the engine and other parts like the stock oil pump arn't quite designed really for 7k rpms all the time anyway
I'd only rev to 7000 rpms either if you're NA or you build an engine to handle it and have good cooling mods
7k rpms and 3.12 pulley is putting the vortech blower to it's recommended rpm limit, but if you're going to do that, I'd rather do the 2.87 pulley and a 6500-6600 rpm redline and get more torque which the vortech can use more of.
The peak hp will be close to the same anyway. For instance:
400whp and 300 tq @ 7000 rpms and with the 3.12 pulley
vs
400whp and 323 tq @ 6500 rpms with the 2.87 pulley
the fuel requirements are going to be about the same
The engine will make more tq which IMO is easier on the engine than going beyond redline, the engine getting even hotter from the rpms, and still having to deal with 400 whp on top of that. Not to mention the engine and other parts like the stock oil pump arn't quite designed really for 7k rpms all the time anyway
I'd only rev to 7000 rpms either if you're NA or you build an engine to handle it and have good cooling mods
anyone? I need to find out what the boost breakdown is for the different pulleys? I dont think 13.5 psi is healthy on a stock block.
Last edited by ekelly36; Oct 7, 2008 at 01:21 PM. Reason: more info
Thread Starter
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on a non-revup,
6-8 psi is normal for the 3.33
8-9 psi is about normal for the 3.12
9-13 psi is about normal for the 2.87
it really completely depends on how extensive your breathing mods are since more breathing lowers the psi. I would stay far away from 13psi and try to stay under 12 psi if possible
6-8 psi is normal for the 3.33
8-9 psi is about normal for the 3.12
9-13 psi is about normal for the 2.87
it really completely depends on how extensive your breathing mods are since more breathing lowers the psi. I would stay far away from 13psi and try to stay under 12 psi if possible
Last edited by sentry65; Oct 7, 2008 at 01:20 PM.
on a non-revup,
6-8 psi is normal for the 3.33
8-9 psi is about normal for the 3.12
9-13 psi is about normal for the 2.87
it really completely depends on how extensive your breathing mods are since more breathing lowers the psi. I would stay far away from 13psi and try to stay under 12 psi if possible
6-8 psi is normal for the 3.33
8-9 psi is about normal for the 3.12
9-13 psi is about normal for the 2.87
it really completely depends on how extensive your breathing mods are since more breathing lowers the psi. I would stay far away from 13psi and try to stay under 12 psi if possible
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I have a few mods to go along with the 3.12, I'm looking at the 2.87, what else should I be looking for?
Edit: I know this has been asked before, but I want to upgrade my IC, can I use any other IC or it too much of a pain/not worth it, thanks in advance.
Edit: I know this has been asked before, but I want to upgrade my IC, can I use any other IC or it too much of a pain/not worth it, thanks in advance.
Last edited by TSG-Z; Oct 7, 2008 at 01:58 PM.
well it is like 2.8 or 9.... cant tell exactly with the bolt on why would it boost almost 14 psi? I have a 32 cog pulley on the top and a 28 cog on the supercharger... My kit is the non revup. so weird.... all the math says I should be at around 12 psi... I guess I will have to just keep my redline at 5500 to stay below 11 psi.... 
maybe I can get someone to trade me for a 3.12 that is local 
atleast then I could get my redline back to 6400
maybe I can get someone to trade me for a 3.12 that is local atleast then I could get my redline back to 6400
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From: phoenix, AZ
you counted the cogs? there's 32?
Yeah I'm running out of ideas. 14 psi is pretty high for the 2.87 especially if you have HF cats and exhaust
what exhaust do you have anyway? maybe the cats got ruined and the debris is stuck in a muffler or something which would raise the psi?
hard to answer without knowing what you have on your car. Full kit?
550cc injectors, a walbro fuel pump, a retune, and probably ECU flash to scale the injectors up
Yeah I'm running out of ideas. 14 psi is pretty high for the 2.87 especially if you have HF cats and exhaust
what exhaust do you have anyway? maybe the cats got ruined and the debris is stuck in a muffler or something which would raise the psi?
550cc injectors, a walbro fuel pump, a retune, and probably ECU flash to scale the injectors up
Last edited by sentry65; Oct 7, 2008 at 03:56 PM.
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Sorry, I have tuner kit 3.12 pulley w/ Crawford plumium, Nismo cams, Walboro 255, UTEC, 650cc injectors, test pipes, Headers and Forged S1 shortblock.
I have to take it and get it retuned anyways it may have had something to do with that fact my compression was jacked.... my new motor should be in tomorrow and then I just need to break it in and install my vortech again.... I talked to my tuner and he said I was only hitting 11.5 psi but I could have swore he said 13.5 .... I will see how it goes at the end of the month....
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should be a good setup
I have to take it and get it retuned anyways it may have had something to do with that fact my compression was jacked.... my new motor should be in tomorrow and then I just need to break it in and install my vortech again.... I talked to my tuner and he said I was only hitting 11.5 psi but I could have swore he said 13.5 .... I will see how it goes at the end of the month....
