Boost loss

[01yellercobra]

Does a RPM belt slip less than the green or standard belt?

It stronger so it doesn't stretch, but also stickier. I think it's only supposed to be at 25% or so of normal tension. Other wise it breaks.

Justin, how hard would it be to pull the EGR valve and block it just for a couple tests? Although at this point I'd say get rid of it anyway. Not like the YSi is legal.

 

[Badaz01]

112.4” gates HD. Yes it is 8 rib. I had the thump tensioner maxed out and needed two people to pull the belt over the water pump pulley. It’s a 15% od with a 2.95 griptech. I’ll see if I can get a video up, but the belt is tight enough to make a bass guitar noise when you touch it ha.


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Well buddy I’m in the same boat you are now. Pulled 1st into 2 nd today and heard a weird slapping sound for a second thought that didn’t sound good. Pulled into garage and what do you know belt shreds and about 4 ribs left on my belt. Thankfully I’m goin in the shop Monday with a American racing solutions tensioner and a half inch smaller belt. Hopefully this helps. It’s gonna be 6 rib still with a 10% O.D. Crank and 4 inch blower pulley.

 

[01yellercobra]

Well buddy I’m in the same boat you are now. Pulled 1st into 2 nd today and heard a weird slapping sound for a second thought that didn’t sound good. Pulled into garage and what do you know belt shreds and about 4 ribs left on my belt. Thankfully I’m goin in the shop Monday with a American racing solutions tensioner and a half inch smaller belt. Hopefully this helps. It’s gonna be 6 rib still with a 10% O.D. Crank and 4 inch blower pulley.

Bite the bullet and go 8 rib. You can buy the F150 pullies fairly cheap. At least you used to be able to. Aligning them can suck, but it'll be worth it in the end. My D1 always had some slip with a 6 rib set up.

 

[JGDogg10]

Well, after tearing shit apart and putting it back together a bunch of times I randomly found what was going on… I thought maybe my blow off valve was getting a greater pressure differential from the psi between the blower and intercooler and what was being fed from the vacuum source off the intake manifold. Just to try and stiffen up the spring for testing I took the blow off valve apart and added two washers under the spring, put it back together and the car would barely make 2 pounds of boost. Frustrated, I took the blow off valve back apart and looked at how it operated inside. The source line comes in through the top, and then feeds two small holes that lead to the diaphragm and the back of the valve. I originally switched my fitting on top of the blow off valve from a banjo bolt to a AN fitting to clean things up, so I thought about switching back to the banjo bolt and when I removed the AN fitting from the top of the blow off valve I saw that it had about an inch of threads going inside the blow off valve. So I screwed the AN fitting back all the way in and blew on that fitting and realized the air was barely getting through the two small holes to the diaphram to hold it down while under boost. I unscrewed the AN fitting all the way up until the bottom of the threads was flush under the blow off valve (not sticking down and inch inside it) and blew on the fitting and a ton of air was going through those two passages onto the diaphram. So I took my fitting and cut off about 3/4 of the threads, popped some Teflon on them and screwed the fitting in. Hooked all the lines back up and just took it for a drive! And sure enough the car is hitting 20+ pounds of boost in 3rd gear!! Car pulls way harder throughout the gears and the supercharger even sounds better while driving.

Bottom line, the length of threads on the fitting were restricting air to the blow off valve diaphram, not providing the correct amount of counter pressure to fully shut the valve after about 14-15psi!

It’s funny how you sometimes just happen to stumble on the answers to your problems by actually taking three time to LOOK at shit hahaha

 

[geoffmt]

Ah man that awesome you found it. I was about to ask what you had for blow-off or wastegates or boost control(sorry relating to turbo issues I have had) I have had something as simple as the vacuum line pop off for the boost controller, also had eboost 2 lose its mind once or twice. Also had the computer pull timing with crappy e85. It’s frustrating and I am glad you found it!


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[JGDogg10]

Blow off is a Tial q50, no waste gates or boost controllers. Thinking now of dropping to a 2.75 pulley from my 2.95

 

[01yellercobra]

When are you going to start bringing this thing out?

 

[JGDogg10]

When I get all the tuning dialed in, and all my loose ends buttoned up. Hah. Which seems to be never. But really, I’m trying to get it all done as soon as possible

I posted in the tuning section, but now can’t seem to get my wideband and sct livelink to match up. Voltage from the gauge seems off…

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[robvas]

When I get all the tuning dialed in, and all my loose ends buttoned up. Hah. Which seems to be never. But really, I’m trying to get it all done as soon as possible

I posted in the tuning section, but now can’t seem to get my wideband and sct livelink to match up. Voltage from the gauge seems off…

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Are you using the right conversion factor?

 

[JGDogg10]

I’m not even at that point yet. I was just sticking with voltage until it seemed close, it’s a 0-4v o2 sensor but it’s idling around 3.4v, which seems way high. It also will spike to above 6 volts when revving it quick and letting off. I’m thinking it has to do with the wiring to the x4 because my gauge is reading right at 1 lambda (14.7afr) but even using autometers formula (v*2.5)+10 it shows the car idling over 16 afr. Short and long trims are spot on within 2-3% of 1.0


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