Hey guys,

I've had my Whipple on my Mark LT for a few weeks now and I really like it. It really gave my truck the boost (pun intended) it needed, especially because I have a big lift and big tires.

I had a few questions about some things I'm noticing or experiencing though, and was looking for any advice or tips.

The first issue I'm having, has to do with my vac/boost gauge. All my gauges are AEM. But with my boost gauge, about half the time when I start the truck up, the needle shoots right up to 0 psi, instead of being in vacuum. So when I'm just driving down the street like normal, it shows I'm at like 10 psi of boost and when I actually hit it, I'm at 16-18 psi. LOL. I know this isn't right. However, some of the time when I start the truck, the needle will be at about 20 pounds of vacuum (of it's still considered pounds in vacuum, I don't know), and then when I actually am in the boost, it's only reading about 6 to 6.5 psi at most. I am also running just the standard Whipple tune at the moment, and with the gauge being all wacky, I don't even know if I'm getting the 8psi that's advertised with this kit.

So my question is; did my installer tap the wrong line (or whatever it's called) to hook up the vac/boost gauge? Or is my gauge faulty, etc? The shop who installed it was aware of this, but he tried to tell me I need to calibrate the gauge by turning the key to the accessories position for a few seconds and then start the truck up...and I'm suppose to do this every time. I've never heard of this before, and I'm not sure if that even makes sense. And even when I do this, it still only works about 50% of the time.

My A/F normally is between 14-15 and in WOT between 11-12 so I think that's all good.

However, I was wondering what "normal" EGT's are? With normal driving, mine seem to be between 800-900 degrees and sometimes at 1,000. However, when I tow my flatbed trailer with my Side By Side Machine on it (about 2,500 lbs total), I've seen the EGT's get up to about 1,350 when I'm pulling a hill and into the boost. Is that too hot? I've never seen it get above that yet. And again, I'm running just the Whipple tune.

I've got a few pics of it below, and I appreciate any feedback:

 

Sounds like your vac/boost gauge needs to be calibrated or replaced.The 20-22 vac reading at idle and 6-6.5 reading at WOT sound right. But the other readings do not.

Your egt readings sound like the sensor is located to far away to provide any meaningful data. I'm guessing it's in your header collector by the temps you provided. The sensor need to be installed in the header primary of cylinder 4 or 8. Install in cylinder 4 is not possible with the headers already installed so you will want to use the primary for cylinder 8. (Driverside closest to firewall.) The sensor needs to be located in the primary not more then 1 inch from the head. It's easy to do. Takes about 20-30 minutes.

Congrats on getting a great ride supercharged!!

 

how much did it cost you part and labor for the whipple? did you get it used or new?

 

Hey Twin, thanks for the feedback.

So do the temps I'm getting seem too cool to be accurate?

And as far as the installation of the boost/vac gauge, is there more than one spot it could be "tapped" into, to provide readings (if I'm asking that right)? Meaning, if the sending unit (or whatever it is that sends the info back to the gauge) is installed in the incorrect place, it could be providing these weird readings. Because as I said, it works about half the time as it's supposed to. Today for example, it was accurate while I was running around doing errands to where I was shutting off and starting up the truck multiple times.

 

Sent you a PM.

 

I think what you said is right TWINSKREWD, my gauge A / F also remains 14-16 and 11-12 at WOT, the one and only difference is that, when I'm parked for example, a traffic light, I see 16 "vacuum those 20 to 22 vac reading at idle perhaps only in the morning, or your engine is very good or mine already has wear. another important point is that you do not mention the needle swings that may indicate some other problem, but error reading by the values ​​that are not true, which indicates that the value of the input signal to your gauge is not correct.

 

my first boost gauge was a mechanical one with a needle, I tried it for 2 days and got sick of trying to determine what was the exact number

since then I returned the needle gauge and got AEM electrical/digital, and it is so much better to see the digits, and some gauges have a usb port so you can retrieve the datalog, but it is a lot more expensive

 

Whipple provides a tap near the rear of the blower that I used but its a pita once the blower is installed so I found out. They talk about it in the manual.

 

Yes to cool on the EGT. You should be around 1350F cruising at 2000rpm. Now that may very a bit. Could be a little higher or lower. Weight and exhaust efficiency plays a role. As for vacuum gauge connection, the Whipple has 2 dedicated ports in the manifold just behind the bypass valve. (See item 47 in your manual) One already has a nipple in it and hose running to the bypass valve. You can tee in to this line. Or you can remove the 1/8" NPT plug next to the factory installed nipple and install a fitting for your vac/boost gauge to connect to.

 

Doing a T fitting will be easier, as I said the NPT plug is what I did after blower install and it was sort of a pain in the ***