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Discussion Starter · #1 ·
I bought my '11 coupe from an estate sale. It was claimed to be bone stock, but I noticed the boost gauge pegs under WOT. I assumed the gauge was just optimistic. To verify, I plugged in an OBD2 reader and did a pull on the highway and it shows I'm getting just over 14psi at high RPM and 11.5 at lower RPM. So the car is obviously not stock. And I have no idea what's been done to it.
I assume I can measure pulley diameters to check that they make sense with the boost. What else can/should I look for? I assume it has a tune, but have no idea who set it up or what they did. Are injector changes easy to spot? What else should I look for? Luckily, I've been running 93 octane in it (it's hard to find 93 around here, but I know of 3 stations).
I guess that explains my perception that this car has significantly more grunt than the Gen 3 Viper I had a year ago. I thought I was crazy...
 

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Look at the upper pulley. What is the CAI?
 
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The only way to really tell is you have to pull the tune and cross reference it with a stock tune. If you have a local tuner near you that uses HP Tuners, he would be able to pull your file/ tune and see if it matches a stock one. Other then that you can try and post pictures of the engine bay and we'd be able to point things out to you that are not stock. The injectors are king of hard to tell. As for a ported Throttle body/ snout/ supercharger, you'd have to pull the TB off ( check it out) the snout, you should be able to tell ( again take pictures and post them so we can tell you if your unsure) and the S.C., your would have to pull the supercharger lid off to really tell.
 

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The air intake is not stock. I can't read the part number on the serpentine belt too well. If you have the brand and part number, you can look up the belt length and use that to determine if you have stock pulleys or not.
 

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Upper looks stock, possibly a lower, but to be at 14 psi you need to have a fair amount of work done to it. As mentioned above ported s/c maybe ported heads/cam. Can you hear any lope from the car? Headers or stock manifolds?
 

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Discussion Starter · #7 ·
The belt is below K080670. Looks like stock exhaust manifolds. No noticeable cam lope.
153061
 

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Discussion Starter · #9 ·
I did a little looking and it looks like this belt length is suggested for 8.6 lower 2.5 upper. On WeaponX website, it says that combo should give 14psi, which is what I'm measuring. The upper looks stock, so I'm wondering if it was the stock-looking Metco (which does come in 2.5"). Think I'm on the right track?
 

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I did a little looking and it looks like this belt length is suggested for 8.6 lower 2.5 upper. On WeaponX website, it says that combo should give 14psi, which is what I'm measuring. The upper looks stock, so I'm wondering if it was the stock-looking Metco (which does come in 2.5"). Think I'm on the right track?
Do you have calipers?

It is easy to slide the belt off to measure....to be sure.
 

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I did a little looking and it looks like this belt length is suggested for 8.6 lower 2.5 upper. On WeaponX website, it says that combo should give 14psi, which is what I'm measuring. The upper looks stock, so I'm wondering if it was the stock-looking Metco (which does come in 2.5"). Think I'm on the right track?
Exactly. I use that belt with a 2.45 upper and an 8.6 lower. It doesn't make sense to have just a large lower pulley because of the amount of work involved. If they made a cam change the lower pulley labor is basically free as you need the same access. The only other time it makes sense is if the engine had to be pulled for some reason and the lower was installed at that time.

There's also another issue. You're around the boost limit at which the cats will survive. Too much heat will melt and clog the insides of the cats. Definitely take it to a knowledgeable tuner to look over the build.
 
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but who does lower pulley and possibly cam and no cooling or other exhaust mods
Agreed. Almost seems like someone trying to do a stealth build. Stock upper with big lower to hide obvious mods. Question is was he hiding mods from his wife or the authorities? What state was this in?
 

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If you can, get picture of the opposite side of the engine, more towards the area where you would add coolant to the S.C. (T-stat/ Passenger side) Looking to see if you have a E85 sensor. You will have to take off the engine plastic cover. The cover should pop right off.
 

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Also, see if you can stick your phone down to the lower pulley (crank pulley) and snap some photos to see if you have a aftermarket lower pulley.
 

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Discussion Starter · #20 ·
Also, see if you can stick your phone down to the lower pulley (crank pulley) and snap some photos to see if you have a aftermarket lower pulley.
I'm not sure what I'm looking for to see the E85 sensor. Do either of these pics capture the right area?
153070

153071

For the lower pulley, it's difficult to get a decent pic. See if this looks like anything interesting. It looks like there is writing on the inside. I tried to put the phone down to verify, but it's hard to see.
153072

153073


I was able to read it and it's a Lingenfelter lower. Do you really think the upper is stock (based on the belt length, too)? Or is it just the stock-looking style?
 
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