Incar vid of Boost guage on an UNported Pullied Eaton??

[trey193]

I am looking for an incar vid of an UNported Pullied eaton , either one with a Hilton Overlay or aftermarket guage would be nice, looking to compare boost drop on my upper pulley only eaton. Just seeing how much drop is normal with the pullied eatons out there, for comparisons sake please do 4th gear pulls and be careful!!!!

 

[MalcolmV8]

You know I've been wondering like mad myself about where the needle should be. I have a 2.76 upper and a steig stage 4 port and as I recall (this was done a few years ago) the boost gauge swung beyond the 10 mark. Recently my son was commenting on my boost gauge and how it was swinging to the 10 and I said no it goes beyond the 10 and we start arguing so we go out for a drive and sure enough the he was right. The gauge swings to the 10 and no further. I could have sworn it used to go further. I recently snapped a s/c belt and still had my stock one in the shed so I put that on and it made no difference on the boost gauge.

Thanks
Malcolm

 

[BlueSS]

I believe there is a peg or something behind it that you need to take off in order for it to go past the 10 mark. You have to do that if you get an overlay and recalibrate it. :shrug: I'm sure someone will chime in who's a 100%.

 

[MalcolmV8]

I've never removed any peg. does anyone know for sure?

 

[Silver2003Cobra]

the only mods I've done to mine are a 2.8" pulley and it will swing (at sea level) down to about where the 15 would be.. even at 5200 ft it goes to where the 12 psi would be. I'll get a video of it today and post online..

 

[venom one]

The boost gauge needle has a tiny peg that stops it from going past the ten unless it's removed.

 

[c6zhombre]

this is my 2.76 car with a hilton overlay. 3rd gear roll

[ame="http://www.youtube.com/watch?v=wJH3o5Z-RK4"]YouTube - 04 cobra boost overlay[/ame]

 

[c6zhombre]

this is a 4th gear pull, but I kind of wussed out about 5900 :??:



[ame="http://www.youtube.com/watch?v=11yEGV-ocX8"]YouTube - '04 cobra hilton boost overlay[/ame]

 

[chet3310]

I like the overlays. Don't you have to calibrate it or did it just overlay? I might have to get one of them.

 

[trey193]

C6Hombre thats what I am looking for, gonna go compare 3rd and 4th to yours tonight, also gotta figure out how to post a vid!!!!

 

[MalcolmV8]

The boost gauge needle has a tiny peg that stops it from going past the ten unless it's removed.

Where is this peg? I just went out and looked at my car and I don't see any peg?

 

[MalcolmV8]

Here's my car in 3rd gear. Sorry for the quality but this was at night and made with a cell phone. However you can see the boost gauge hits 10 only. I have a 2.76 upper and stage IV port on the blower, cai and cat back.

[ame="http://www.youtube.com/watch?v=IYyTeH1X9xk"]YouTube - 03 cobra 60 to 100 mph in 3rd[/ame]

Thanks
Malcolm

 

[trey193]

Before I got my overlay on mine would swing way past 10 , much farther than yours does Malcolm. Have you verified boost with an aftermarket guage?? If not you ought to. Most dynos have boost stacks to verify boost as well. C6Hombre is looks like your car on the 4th gear pull holds 13lbs of boost up to when you cut it off around 5800 doesnt look to drop much if any, looks like it went a tad past 13 on the initial hit and then drops slightly right back to 13 and stayed there, on the 3rd gear pull Boost drops more noticeably, not sure why but mine does the same thing.

 

[MalcolmV8]

Before I got my overlay on mine would swing way past 10 , much farther than yours does Malcolm. Have you verified boost with an aftermarket guage?? If not you ought to.

I have not but I'm almost 100% certain mine used to swing way past the 10 back in the day when I first had the mods done. After my blower belt snapped and I put a new one on I fired up the car and I noticed the blower has an odd noise coming from it while the car is just sitting there idling. Almost like blower whine but a little different. Perhaps my eaton is messed up. Oh well I have a rod knocking now so bigger issues to fix before I get my car running again. Once it's running again I'll look back into the boost issue.

 

[c6zhombre]

C6Hombre is looks like your car on the 4th gear pull holds 13lbs of boost up to when you cut it off around 5800 doesnt look to drop much if any, looks like it went a tad past 13 on the initial hit and then drops slightly right back to 13 and stayed there, on the 3rd gear pull Boost drops more noticeably, not sure why but mine does the same thing.

i'm no tuner, but i think the lower gears like 1st, 2nd or 3rd rev so fast that the boost bleeds off quicker. maybe 4th gear revving longer can maintain the boost level

the only other difference was i took those vids on two different nights. the 3rd gear vid was like 80 degrees/humid. the 4th gear pull vid was much cooler/drier air, maybe 58 degrees

 

[Silver2003Cobra]

went out and tested my boost guage (at different elevations) you can easily see it pass 10 psi and I'd guess goes around 12 psi in the first part at 5145 ft elevation and maybe 9 psi max in the 2nd part when I'm at 8737 ft elevation (both filmed today) and never touched the instrument cluster..

[ame="http://www.youtube.com/watch?v=wGr-95bm0vQ"]YouTube - elevation_boostguage.mpg[/ame]

 

[trey193]

Good info!!!! Gonna try do a comparison later on!

 

[Smacked_in_ATL]

Nice vids guys, but what I'm noticing no one has done the mod that prevents boost from dropping off ~6000 RPMs with a stock/pullied setup. What is this mod called and does anyone know how to do it correctly?

 

[Silver2003Cobra]

Nice vids guys, but what I'm noticing no one has done the mod that prevents boost from dropping off ~6000 RPMs with a stock/pullied setup. What is this mod called and does anyone know how to do it correctly?

there is no mod to prevent that from happening, it's due to the inefficient design of the Eaton supercharger that we have. When you port them, it helps but nothing you can do to the overall design of the M112. This is why a lot of people switch to the Twin Screw superchargers which from what I've read don't drop off anything like the M112.

 

[trey193]

I was told to take the vacuum hose that runs to the FRPS and T into that hose and run it to the top port on the boost actuator(or one facing towards front of vehicle) and cap off the line that originally fed that port and the one running from the intake tube by the throttle body over to the other port on boost actuator(one facing firewall), and leave that port on the acuator open to atmosphere??