Can i install the 3.12 pulley on my vortech without changing my injectors and just getting a tune? or will i blow my motor?

 

A lot of guys start off with the 3.12. Slap it on and tune it up

 

No one can give you a definitive answer. However, it can be said that you will likely be reducing the safety and reliability of your set-up w/o upping the fuel delivery to match the increase fuel demand..More power = more fuel..The stock fuel system has worked well for many who have gone to the 3.12 but they likely do not know what there inj duty cycle is. Close to 80% is considered the threshold for unsafe.. The FMU and Aux fuel pump would likely satisfy the fuel needs but a dyno would verify it...Sounds like a trip to Gaithersburg is in your future..

 

The stock set up runs rich and you may get by with out tuning it . But I wouldnt do it with out tuning it . Stock pulley or 3.12 , you should have it tuned

 

The stock Vortech fuel system works fine with the 3.12 Pulley. But it MUST be Tuned. Make sure that your AFR is about 11.5 to 11.8 after about 3lbs of Boost. Perferably getting richer as you move toward redline.

With more boost you'll need to retard the Timing more, that is if the first tune was set-up right. The amount of retard Varies, but 1 degree of retard to 1lb of boost is more than enough up to 9lbs on 91 octane. I use 93 and with my 3.12 I was pulling out 7 degrees, with the 2.87/12lbs of boost Im pulling 13@redline.
A good tune retards the timing just enough so there is No Detonation under all driving contitions.

 

Ok cool thanks, i have my car tuned by AAM right now and am pulling 10lbs of boost in the cold weather, it was 9 over the summer on the stock pulley. I think im going to upgrade to the 3.12 pulley, leave the injectors and go to AAM to get the car retuned on the dyno..... hopefully ill be pushing out over 400hp i was at 384 on the stock pulley. Gotta get it tuned im too nervous to push it to redline with out the tune, even now the car sputters a little when approaching 7200, but i have revved out to 7400 before

 

If it sputters now with the 3.33 + tune why do you think its gonna be safe with the 3.12 + tune and no upgrade to the fuel?

 

Tuning is not an option, it's a must!

 

2nd gear sputters up top 3rd gear i can rev out past 7000 without any sputtering same with 4th and 5th and 1st just in 2nd for some reason, and im just hoping that it can be cured with a new tune...... If it can not be cured with a tune ill just have to opt for injectors

Hey JPC i think i met you when i was having my Vortech installed at AAM you were having this pulley installed, what was your reaction? how do you like it? give me some inside info here man

 

Really brings on boost sooner and higher..Car runs well however I'm beginning to look for more like the 2.87 pulley.. Never satisfied..You really should consider upgrading the fuel system..I did with 440 and walbro then tuned..Only concern I have is the fuel press is higher than I like but AAM say's no problem...MIA has sent me a copy of Turbonetics install procedure and it has a step ( opening the regulator passage) that might help reduce the pressure..Go with the 2.87 upgrade the fuel to a return system tune it and you'll be getting about as much as a vortech can give you.. Good Luck

 

Yea thats a little over budget for me these days but otherwise it sounds great....thanks for the info