Boosting my 95SC4 and some other projects
#136
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Ok, the reason I haven't been posting.
I am having trouble making boost. I'm not really sure why, I've been spending about 90% of my free time working on my car trying to figure it out.
Seems as though there are only three real possibilities. 1 I have a big boost leak somewhere, I don't think this is the case but I'm not 100% sure. 2 I have a big restriction somewhere. 3 The V-9 is either to small for the engine or it's worn out enough that it's not blowing to it's full potential.
I'm really at my wits end trying to figure out why I'm not getting boost. I have a few more things to try before I do any major re-configuring. If I can't find any leaks or restrictions, I guess I'll try running from the supercharger to the intake using the shortest route possible and see what happens.
Couple of notes. I have seen 4psi a few times, but not consistently. The V-9 F-trim is rated at 725cfm, which is kind of low but the V-9 G-trim is rated at 875cfm and is used on LS1 / LT1 (5.7) motors to blow 8-9psi. So I wouldn't think that the F-trim is too small for the little 4.0.
I don't know, but I'm frustrated and tired of working on it at this point. If anyone has ANY suggestions or ideas of what to check, or what the problem could be, please let me know.
I did put a mechanical gauge on the throttle body (before the plate), didn't show any boost untill I closed the throttle. At that point the needle fluctuates (compressor surge) between 6-7psi or so. The next thing I'm going to try is to get a reading right of the snail. If I have any psi at WOT, I would think that would mean there is a restrition. Or, if I show more than the 6-7 psi that I saw at the throttle body.
KC
I am having trouble making boost. I'm not really sure why, I've been spending about 90% of my free time working on my car trying to figure it out.
Seems as though there are only three real possibilities. 1 I have a big boost leak somewhere, I don't think this is the case but I'm not 100% sure. 2 I have a big restriction somewhere. 3 The V-9 is either to small for the engine or it's worn out enough that it's not blowing to it's full potential.
I'm really at my wits end trying to figure out why I'm not getting boost. I have a few more things to try before I do any major re-configuring. If I can't find any leaks or restrictions, I guess I'll try running from the supercharger to the intake using the shortest route possible and see what happens.
Couple of notes. I have seen 4psi a few times, but not consistently. The V-9 F-trim is rated at 725cfm, which is kind of low but the V-9 G-trim is rated at 875cfm and is used on LS1 / LT1 (5.7) motors to blow 8-9psi. So I wouldn't think that the F-trim is too small for the little 4.0.
I don't know, but I'm frustrated and tired of working on it at this point. If anyone has ANY suggestions or ideas of what to check, or what the problem could be, please let me know.
I did put a mechanical gauge on the throttle body (before the plate), didn't show any boost untill I closed the throttle. At that point the needle fluctuates (compressor surge) between 6-7psi or so. The next thing I'm going to try is to get a reading right of the snail. If I have any psi at WOT, I would think that would mean there is a restrition. Or, if I show more than the 6-7 psi that I saw at the throttle body.
KC
#137
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Double check your PVC system. Remember boost is a measure of pressure. High flow cats or heads will decrease boost. Secondly, you have to take crank pulley diameter in consideration. You can not compare what this blower make in other engine or how much it flows. Couple of factors you should look into:
1. Crank pulley size
2. Charger Pulley Size
3. PVC and vent system
4. Compression Ratio
5. Exhaust flow.
1. Crank pulley size
2. Charger Pulley Size
3. PVC and vent system
4. Compression Ratio
5. Exhaust flow.
#138
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PCV.
I haven't driven it yet, I'll know for sure tomorrow.
The stupid line without a check valve that goes to the passenger side valve cover from the throttle body.
I was doing some testing earlier today. Had 12psi or more at the snail, 12psi or more after the maf where the vac hose for the p/s idle up accuator goes, but only 5-6 psi at the throttle body ports. Took off the intake from the maf to the throttle body and discovered the hose. Took out the PCV valve on the driver side, stuck a hose in the hole and hooked up a vac/pressure gauge and I had 10 or so psi coming out of the valve cover! I don't think I've blown out any seals.
Stupid oversight on my part. I'll know if it's fixed on my way to work tomorrow.
KC
I haven't driven it yet, I'll know for sure tomorrow.
The stupid line without a check valve that goes to the passenger side valve cover from the throttle body.
I was doing some testing earlier today. Had 12psi or more at the snail, 12psi or more after the maf where the vac hose for the p/s idle up accuator goes, but only 5-6 psi at the throttle body ports. Took off the intake from the maf to the throttle body and discovered the hose. Took out the PCV valve on the driver side, stuck a hose in the hole and hooked up a vac/pressure gauge and I had 10 or so psi coming out of the valve cover! I don't think I've blown out any seals.
Stupid oversight on my part. I'll know if it's fixed on my way to work tomorrow.
KC
#139
Lexus Champion
iTrader: (-1)
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I was doing some testing earlier today. Had 12psi or more at the snail, 12psi or more after the maf where the vac hose for the p/s idle up accuator goes, but only 5-6 psi at the throttle body ports. Took off the intake from the maf to the throttle body and discovered the hose. Took out the PCV valve on the driver side, stuck a hose in the hole and hooked up a vac/pressure gauge and I had 10 or so psi coming out of the valve cover! I don't think I've blown out any seals.
Stupid oversight on my part. I'll know if it's fixed on my way to work tomorrow.
Stupid oversight on my part. I'll know if it's fixed on my way to work tomorrow.
Assuming you are making boost, now you can let that boost limiter valve do its magic by pulling some boost from the system so that you can tune it up with boost at a reasonable level.
I am hopeful.
Good Luck.
#140
Lexus Champion
iTrader: (4)
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PCV.
I haven't driven it yet, I'll know for sure tomorrow.
The stupid line without a check valve that goes to the passenger side valve cover from the throttle body.
I was doing some testing earlier today. Had 12psi or more at the snail, 12psi or more after the maf where the vac hose for the p/s idle up accuator goes, but only 5-6 psi at the throttle body ports. Took off the intake from the maf to the throttle body and discovered the hose. Took out the PCV valve on the driver side, stuck a hose in the hole and hooked up a vac/pressure gauge and I had 10 or so psi coming out of the valve cover! I don't think I've blown out any seals.
Stupid oversight on my part. I'll know if it's fixed on my way to work tomorrow.
KC
I haven't driven it yet, I'll know for sure tomorrow.
The stupid line without a check valve that goes to the passenger side valve cover from the throttle body.
I was doing some testing earlier today. Had 12psi or more at the snail, 12psi or more after the maf where the vac hose for the p/s idle up accuator goes, but only 5-6 psi at the throttle body ports. Took off the intake from the maf to the throttle body and discovered the hose. Took out the PCV valve on the driver side, stuck a hose in the hole and hooked up a vac/pressure gauge and I had 10 or so psi coming out of the valve cover! I don't think I've blown out any seals.
Stupid oversight on my part. I'll know if it's fixed on my way to work tomorrow.
KC
Ryan
#142
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I'm not sure, but I think he's talking about the half moons. On many toyota's, there is what looks like a cam journal on the head, but no cam uses it. There are metal half moons that fill the space, they are usually sealed with FIPG. I don't think they'd be a problem if you make sure to put a check valve on the hose that goes in between the throttle body and the valve cover.
KC
KC
#143
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Ok, so putting a PCV on that stupid hose made no difference with my lack of boost, but at least now, I'm not putting pressure in the crankcase.
I did, however, discover two very interesting things a few minutes ago.
First, the ultimate intake leak test. I took a hefty freezer bag and put it on the inlet of my supercharger. The cheese filter I bought from advanced auto has a removable, rubber reducer ring. I put that ring over the plastic bag and used the hose clamp to secure it, sealing the inlet. I then pulled a vacuum hose off one of the vsv's and used a blow gun to pressurize the whole intake to about 2 psi. From there, look, listen and spray lots of soapy water.
Well the first interesting thing I discovered is that my maf sensor is leaking air. The actual sensor is leaking out the top of it. It's actually kind of scary, if you watch the sensor as the intake is being pressurized, you can see the top cover of the sensor flex. And I was only using 2 psi. I'm surprised no one with FI on these cars hasn't blown one apart yet. Anyway, the sensor should be going bye bye very soon.
The second and I think most significant thing I found is that my egr valve leaks. It's somehow leaking out of the housing, and it's a pretty good leak. I am also assuming that if it's leaking out of the housing, then it's probably also leaking into the exhaust.
So, there is still hope for me. I was really beginning to think that the V-9 is just too small. The egr valve was about the only thing that I hadn't yet checked that could possibly leak enough air to prevent boost. So hopefully tomorrow, I can find a way to block the port, then I should know one way or the other.
KC
I did, however, discover two very interesting things a few minutes ago.
First, the ultimate intake leak test. I took a hefty freezer bag and put it on the inlet of my supercharger. The cheese filter I bought from advanced auto has a removable, rubber reducer ring. I put that ring over the plastic bag and used the hose clamp to secure it, sealing the inlet. I then pulled a vacuum hose off one of the vsv's and used a blow gun to pressurize the whole intake to about 2 psi. From there, look, listen and spray lots of soapy water.
Well the first interesting thing I discovered is that my maf sensor is leaking air. The actual sensor is leaking out the top of it. It's actually kind of scary, if you watch the sensor as the intake is being pressurized, you can see the top cover of the sensor flex. And I was only using 2 psi. I'm surprised no one with FI on these cars hasn't blown one apart yet. Anyway, the sensor should be going bye bye very soon.
The second and I think most significant thing I found is that my egr valve leaks. It's somehow leaking out of the housing, and it's a pretty good leak. I am also assuming that if it's leaking out of the housing, then it's probably also leaking into the exhaust.
So, there is still hope for me. I was really beginning to think that the V-9 is just too small. The egr valve was about the only thing that I hadn't yet checked that could possibly leak enough air to prevent boost. So hopefully tomorrow, I can find a way to block the port, then I should know one way or the other.
KC
#145
Lexus Champion
iTrader: (4)
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I'm not sure, but I think he's talking about the half moons. On many toyota's, there is what looks like a cam journal on the head, but no cam uses it. There are metal half moons that fill the space, they are usually sealed with FIPG. I don't think they'd be a problem if you make sure to put a check valve on the hose that goes in between the throttle body and the valve cover.
KC
KC
Ryan
#146
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If you guys experience oil leaking after the Turbo or Supercharger then your plumbing is wrong. You are pressurizing the crankcase. That is why oil will leak at the weakest part. Make you sure you plug up the TB connection to the valve cover. I would suggest u run a catch can and modify the PVC system so u have all your boost going to the cylinders.
#147
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Guys,
Again, I know I'm a slacker on the updates.
This is a quick one, I will try and be a bit more thourough later.
After I, changed just about every vac line, blocked the EGR, added a PCV to the passenger side vent hose, and fixed a few other problems........
I am seeing around 6psi at 5-6k.
Also, over the last couple of days, I've officially converted to speed density. The leaking MAF is on a shelf in my garage.
Couple of pics...
Again, I know I'm a slacker on the updates.
This is a quick one, I will try and be a bit more thourough later.
After I, changed just about every vac line, blocked the EGR, added a PCV to the passenger side vent hose, and fixed a few other problems........
I am seeing around 6psi at 5-6k.
Also, over the last couple of days, I've officially converted to speed density. The leaking MAF is on a shelf in my garage.
Couple of pics...