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Discussion Starter #1
My blower is tuned to run @ 6 psi, and I dont drive it hard, just the occasional romp.

Its tuned for daily driving with 4.10s in the rear etc...

And for some reason I was hammering it this morning in 4th gear and I would get to about 118mph 6500 rpms and only be at 3-5 psi...

When I would shift to fifth gear it would go way down of course cause the rpms but still...

Is this normal? My boost gauge has been on 5 psi before when I was running it but now it just wont even get to the 5 psi mark...

Could I be losing boost?

I also noticed my methanol injection isnt draining near as fast as it used to, or its not draining at all.... I cant really telll

Car is still fast as F*** I just want to know if you think the gauge is wrong or my supercharger is messing up??

Btw the gauge used to read -20 psi at idle, now its staying at -10. The gauge is also kinda loose too it (The facing) is almost coming out of the case on the pillar.

Please help me I am dying to know, I am prob gonna take it to a performance shop tomorrow but I am nervous about money. I have none rightnow.
 

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Im not sure what your exact question is, but you will lose boost inbetween shifts. The boost on these blowers goes up with RPM's. How much power did you make with 6psi?

Also, you might have a vacuum leak somewhere if its at 10hg. You should be around 20. My BOV got pushed into the harmonic balancer the other day, there was a hole on the top of it and my vacuum went down to like 2hg to 8hg. I was also only making 6psi of boost.

Check to make sure you dont have a boost leak.
 

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Discussion Starter #4
Im not sure what your exact question is, but you will lose boost inbetween shifts. The boost on these blowers goes up with RPM's. How much power did you make with 6psi?

Also, you might have a vacuum leak somewhere if its at 10hg. You should be around 20. My BOV got pushed into the harmonic balancer the other day, there was a hole on the top of it and my vacuum went down to like 2hg to 8hg. I was also only making 6psi of boost.

Check to make sure you dont have a boost leak.
I dont think my car is making as much boost as before is what I mean, and how do I check for a boost leak? Would I be better off bringing it by a performance shop? And my car was 440 rwhp and 400 ft lbs. 510 at the crank
 

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440rwhp with 6psi? God damn! I need to do a 4V swap asap.

Is your car intercooled? How much boost do you think it made before? 6psi right? And what rpm did your tuner bring it up to on the dyno?
 

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Discussion Starter #6
Umm I am not sure I have the dyno sheets.. sec im checking... 440 rwhp at 6400 rpms.

I dont think it's intercooled, but then again I dont know, I bought the car with this stuff on there lol! But its only got 48k miles and the stuff was put on there at like 30k, so its almost new.

I dont run it hard though just occasionally. And its never seen the track.

The methanol injection isnt spraying as much as it did before, could that be an issue?

Also how would I get all this checked out?
 

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Jesus..headache! Buying built cars is not fun.

Im assuming its not intercooled if its has meth. But I could be wrong. Any pictures of the car? Especially under the hood. I can tell you in 1 second if its intercooled or not. If its not intercooled, there will be 1 pipe going from the blower to the motor. If it is intercooled, youll see alot more piping.

Is the meth low? Have you refilled it? Why do you "think" its not spraying as much as it used to?

If the tuner ran the car up to 6400rpm, that means thats where it was making 6psi. Have a friend or someone watch the boost gauge while you hit it, and tell them to watch to see how much it hits. If the blower was going bad, you would be leaking oil.

Could be belt slip. But before you jump to that, have someone watch the boost gauge, and you bring it up 6400rpm in 2nd or 3rd gear.
 

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Discussion Starter #8
You're right "HEADACHE"!

2nd or 3rd eh? Ok well I have 410s let me hope that it will stick to the ground.

And last weekend the meth was reallly low and I refilled it but I was in it and it should have gone down atleast a little bit this week and it hasnt.

I mean I got into it it should have sprayed.



When i got my oil changed, the tube that is tapped into my oil pan has a little bit of oil on it, but wasnt leaking like dripping it just had oil on it just a little bit coming out.

But never leaks anywhere I park over night or anything.

Do you think I should run it to a performance shop and just have them look for a leak?
 

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Thats not intercooled.

Unless you know what to look for, I would bring it to a shop. Get everything checked out and what not.
 

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depending what time of year you get your car tuned you will pick up about 2# of boost in the winter from the cold air. also my blower cars dont hit full boost in first or second cause it goes threw the rpm's to fast.
 

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Discussion Starter #12
Ya my car doesnt get boost in 1st or 2nd. I have 4.10s too so its hard. 3rd ya 4th ya 5th eh.

I hate this ****, I mean its 84 degrees down here and has been for 4 weeks.

I ran it really hard the other weekend and the juice ran out real quick, but this week I tried to run it out to see if its working and it didnt seem to make a dent in the methanol.

Im not sure I guess I will have to go empty my pockets.

How do I check for a boost leak or vacuum leak??
 

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Discussion Starter #13
I had the previous owner tell me to check the boost gauge connection cause it sometimes slips off and it was on just fine. I took it off and put it back on just to see but same issue witht he -10 instead of -20
 

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I moved from Virginia (40 degrees) to Texas (90 degrees) 2 weeks ago. I thought I had a boost leak as well ... but was just the big difference in heat. (Plus the 700ft elevation increase)
 

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Ya my car doesnt get boost in 1st or 2nd. I have 4.10s too so its hard. 3rd ya 4th ya 5th eh.

I hate this ****, I mean its 84 degrees down here and has been for 4 weeks.

I ran it really hard the other weekend and the juice ran out real quick, but this week I tried to run it out to see if its working and it didnt seem to make a dent in the methanol.

Im not sure I guess I will have to go empty my pockets.

How do I check for a boost leak or vacuum leak??
5th gear isnt really a good gear to boost in these cars. 5th is to big of a drop to really get on it. Its not bad once in a while, but doing it a lot isnt good. To much of a load on the motor. If you want higher top end, Id suggest going back to stock gears (3.55) or go to 3.73's.

Like stal said, depending when the car was tuned, if it was in cold weather you will drop 1-2psi.

To check for a vacuum leak, have the car at idle, spray some spots with starting fluid. If the idle changes at all, then where you sprayed it is where its leaking.
 

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Discussion Starter #16
5th gear isnt really a good gear to boost in these cars. 5th is to big of a drop to really get on it. Its not bad once in a while, but doing it a lot isnt good. To much of a load on the motor. If you want higher top end, Id suggest going back to stock gears (3.55) or go to 3.73's.

Like stal said, depending when the car was tuned, if it was in cold weather you will drop 1-2psi.

To check for a vacuum leak, have the car at idle, spray some spots with starting fluid. If the idle changes at all, then where you sprayed it is where its leaking.
Ahh well I will doo that. The car was in Colorado, Hence the methanol injection to help with the compression of the higher elevation. But it was tuned recently down here in Houston. So I dont know man I am just gonna do that or have someone check it out, performance shops rip you off though sadly.
 

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They do, if I were you, sence your in Houston, Ive heard people on these forums say good things about Houston Performance, and Gearheads Performance in Arlington. I had to look that up from 04N20GT's thread. But a lot of people were saying really good things about them.

Go there, just have them look over the car. You can get a re-tune from them too, make sure the meth is working properly. All that.

Sometimes the blowers leak from the oil return line, I have 2 hose clamps on my return line. Still drips a little bit. Pain in the ass.
 

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Discussion Starter #18
I will, theres a place in my area called PSI MOTOR SPORTS, heard theyre pretty reputable. They're mainly mustang performance shop.
 

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It could be the gauge. Is it Autometer? Mine used to read 9psi, now it barely gets to 6psi. Occasionally the needle will also get stuck. It could also be belt stretch. I thought my bypass valve wasn't holding so I threw in a audi/vw bypass valve which is better than the Bosch one that comes from Vortech, and it didn't help. Does it feel slower?
 

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My Autometer gauge sticks at 15-16 in.hg. vacuum at idle. When I tap the gauge it goes to 18-19. I had an Autometer fuel pressure gauge stick constantly.

I realize that the 4v motor is more effecient than the 2v but I was questioning the 6 psi and 440 rwhp until I read that the car was from Colorado. It's good that it was re-tuned because a pulley that generates 6 psi in Colorado could possibly generate 10-12 psi at sea level. I think your best best is to go to a performance shop and get it baselined. That way you will know for sure what you've got.

P.S. On the dyno my car had repeatedly shown 9 psi. I have never seen the gauge go above 6-7 psi. It might but I'm watching other things when I'm WOT at red line.
 
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