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Discussion Starter · #1 ·
i should be safe with an intercooled stock 2.5 if i dont go over 15 lbs boost right?? i'm a little nervous. i do have a iequus a/f gauge, i mounted it in the passenger side power mirror blank. looks cool i'm pretty proud of myself:D
 

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Ya just sit it under 15 psi and then no cut out protection needed...
Unless you are planning on going over 15 psi and manually messing with the fuel
 

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In my experience all of my cars will go up to about 14 to 14.5 before the herking and jerking starts but I have heard of some cars doing it with less boost. But IMO 13 or 14 psi is pretty stout unless your on the strip. My caravan is pretty much stock and at 14 psi it absolutely anihilates the front tires.
 

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Yeah just a hair over 14 PSI is the stock cutout. You can probably set your manual boost controller to a max of 13 PSI because in 4th or 5th gear sometimes the boost ramps a hair higher plus sometimes the boost spikes a hair before settling down.
 

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Im 99% sure your gonna blow it up. Man up and get a 3 bar or turn the boost down. Im not sayin it to be a jerk, I just know from past experince. Diodes suck!
 

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Discussion Starter · #8 ·
thanks for being a jerk, i think i needed that , i was gettin greedy i'm going to cut it out right now....best not to play with fire
 

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I used a 4.7v diode on my old daytona with the log engine. Ran 17 PSI boost with a squished fuel pressure regulator to give me 62 PSI static fuel pressure. I ran 10 degree timing to be safe but I never had any issues with it on pump 93 octane.
 

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Well I had the mopar stage 2 cal, and you have to have one to use the 4.7 diode otherwise you have the use the 4.3 one. Stock computer's cutout is 4.67 volts and the stage 2 is like 4.8 volts or something like that. With the 4.3 the computer only sees like 12 PSI boost, with the 4.7 it sees like 13.5 or so.
Plus with the stage 2 cal the timing and fuel curves are a little more aggressive than stock, so I think it helps as well.
 

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Discussion Starter · #12 ·
so what were the other guys talking about when they asked why i need a diode if im only running 14 lbs of boost
 

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The stock map sensor reads to 14.7psi, the diode is if your running more then that and getting cutout, so you trick the computer so it thinks your only running 14psi or so when your actually running 18 psi. The new term is map clamp

if your just using it to keep the fuel down a little, then thats fine, just most adjust the fuel pressure instead

basically you never state exactly why you think you need or are using a diode
 

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thanks for being a jerk, i think i needed that , i was gettin greedy i'm going to cut it out right now....best not to play with fire
If you have a 2.5 with a mitsu like your profile says, then 14psi should feel plenty healthy. The mitsu falls of at like 17-18 usually on a 2.2 Why chance a stupid diode for 3-4 psi when its probly gonna smoke a piston. Just drive the car and enjoy it. It will probly smoke the average street car anyways.
 

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Best bet is #40's and a 3-bar. I got a FWDP stage 3 and had cindy take the cutout out of the cal...bad Idea #1. Got a little overzealous with the boost...bad idea #2. Had the little mitsu maxed out at 25lbs...third times a charm. Melted number 4 head looked like swiss cheese and the piston was almost nonexistant. But it still made the 40 mile trip back home. Lessons learned don't fool the computer, 5 injectors aren't enough, breaking stuff is fun.
 
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