exhaust leak, cause boost loss?

littleboylan

Registered User
I am in the process of figuring out why im only idoling at 18 in/hg and my max boost is 12 with a 10% pulley, Im figuring something is leaking somewere, and I already tried zip tying all my vac lines, and it dont appear that I have a leak anywere else, I also have heard what sounds like the exhaust when i get on it near my drivers side door, could this cause it? any suggestions would be great help, THanks MIke
 
hmm..

Do you have anything done to the exhaust system in the way of performance. I think an exhaust leak big enough to cause a noticable boost loss would be very obvious. Usually our SC's produce anywhere from 10-12 pounds of boost. So if you pushed around 10 stock, with a 10% you may only be at 12 now. I only gained about 1.5-2 psi from a 10% pulley. Remember, more boost is not necessarily better. Boost is actually back pressure in the motor. Faster you can get it out, usually the better. So your motor may just be more efficeint for some reason. You have any 1/4 mile times on it?

Not sure where it should be setting for the proper idol. I haven't driven mine in so long, i have forgot. Someone else might beable to chip in.
 
kool

Hey I know I have flomasters all the way, no cats, that would probably drop the boost numbers too huh? I just put on a mac cai, Its like I can almost feel a difference with it on, but I dont seem to have gained any boost, according to our oh so accurate gauge, anyways I still think I got a leak somewere, maybe a vacuum line but I really am not sure, hey by the way is your name Mark, with the silver sc?
 
hmm..

That would be me. LOL I know who this is now. Didn't even look at the name till after you just said something.

BTW, I didn't gain any boost from my CAI either. So I wouldn't expect it from that.

Also I woudl consider it normal what you have in boost anyways. Though I push about 14 PSI at WOT.
 
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haha thought so

hey i was wondering you wouldnt happen to know how to rebuild a manual trans would ya, i see all the stuff your going through with your automatic, but you say you did it yourself, i need to get my third gear synchro fixed, actually I went to the track but only pulled off a 15.6 due to missin third gear, DOPE, what a screw I was pissed, anyways I need someone who knows how to pressure test my lines to see if I do have a leak somewere, u got a msn? instant messenging would be so much easier Thanks
 
forgot to mention

at wot I notice that the boost does climb to the 14 range but when I stab it, it jumps to 12 and then slowly climbs from there
 
Re: haha thought so

littleboylan said:
hey i was wondering you wouldnt happen to know how to rebuild a manual trans would ya, i see all the stuff your going through with your automatic, but you say you did it yourself, i need to get my third gear synchro fixed, actually I went to the track but only pulled off a 15.6 due to missin third gear, DOPE, what a screw I was pissed, anyways I need someone who knows how to pressure test my lines to see if I do have a leak somewere, u got a msn? instant messenging would be so much easier Thanks

No, we didnt' rebuild my transmission. Me and my father rebuilt my engine though. With new rings, bearings, seals, and what not. After the engine we were pretty tired out. I took it to one of my friends boss who works at a dealership. But now we have run into trouble where I do not have reverse. And I to am assuming I am losing line pressure with my trans. Because reverse requires full line pressure to apply the clutch pack. So we have been pulling off the valve body and what not and adjusting the throttle cable linkage to see if it changes but it hasn't. So I wouldn't be the person to ask. But there are a ton of people on here who could probably tell you how. But I do have MSN. kram8it@hotmail.com
 
Re: forgot to mention

littleboylan said:
at wot I notice that the boost does climb to the 14 range but when I stab it, it jumps to 12 and then slowly climbs from there

It should do that. That is perfectly normal. Mine also hits 12-13 and then climbs to 14.
 
just added

Hey just added your email to my msn list, u are from around town here aint ya, im trying to think exactly who u are, i just know ya from jared, anyways, I was talking about pressure testin my vac lines to try and find a leak somewere, any help with this?
 
Re: just added

littleboylan said:
Hey just added your email to my msn list, u are from around town here aint ya, im trying to think exactly who u are, i just know ya from jared, anyways, I was talking about pressure testin my vac lines to try and find a leak somewere, any help with this?

Sort of. I live out a little farther actually. Prolly 10-15 minutes from you. You will have to send me a message for me to add you. As for your lines, i would suggest getting a manual that shows the routing of the Vac lines. Then just pull them off and put them back on one by one. I would think the one you come across that doesn't change the idle of the engine would be the one that needs to be replaced. We sorta found Jareds leak that way. Only his was louder. That is how I would do it and have did it before. Is it the best way? Couldn't tell ya. LOL. Its probably the ones on the back of the supercharger. After rebuilding my engine, I had to replaced 2-3 of them because of the bends that ford put on them. Eventually they just cracked.

Come to think about it. I think theres a diagram right on your car. Under the hood. Its one of the stickers, along with the belt rountings. Have you checked those?
 
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ok

so basically just let my car idle and start pulling lines and see which ones change it and which ones dont, and the ones that dont change the idol then there the ones that probably need fixed? right, I think I know what your saying, I should get like a haynes manual or something? I just got this car and know more about it than anyother car ive owned so far, anyways im blabbling, but I cant send you a message cause it says your offline, can you add me?
littleboylan@hotmail.com
 
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