swapped carb to tbi on sunday night...bad idea
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Joined: Feb 2002
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
swapped carb to tbi on sunday night...bad idea
Ok bone head move number 1,243,243,414. I decided to swap to my 454 tbi on sunday night since all I had to to do is splice my pump in line and throw the throttle body on. well that took 2 hours and the next 6 i spent figuring out every stupid little thing that went wrong.
Prob. 1
Won't start, starts if i put gas in tb, only sprays for like 2 sprays. then quits once started runs fine.
answer.
I figured this one out in the shower at 3 a.m. I used an ignition hot to turn on the fuel pump. It was from inside the car which gets turned off when you crank on the engine.
Sounds like your problem pablo.
Prob 2
High idle and extremely loud hissing noise. Pretty sure its the iac controle because it doesn't click at all when i turn on the engine. Gonna try to reset it and check wireing... I looked at some other post with the same problem.
answer. ? what do you think
prob 3
Linkage binds and won't seat half time. Works fine with motor off. Must be manifold vacume sucking on the blades or somthin
answer?
Prob4
Linkage adapter I made sucks.
Answer.
Switch majors because I don't believe someone this stupid should not be an engineer. Linkage goes to wot throttle perfect just won't seat half the time and is really hard to push the pedal for the first 25% of the throttle.
Prob 5
Drop base air cleaner won't fit.
answer
Buy a non drop base
If I can't fix all this in an hour or so tonight i'm gonna have to swap the carb back on. I gotta get it runnin tonight. The big problem i'm having is figuring out what the loud hissing noise is. I'm pretty sure there is no vacume leak. This hiss is so loud it's almost defening. Is it possible to run without a IAC if i set the idle screw up enough? All that put aside it revs like no carb I have ever played with and sounds strong, got blm's in the ball park in 2 burns. Just can't drive it.
Prob. 1
Won't start, starts if i put gas in tb, only sprays for like 2 sprays. then quits once started runs fine.
answer.
I figured this one out in the shower at 3 a.m. I used an ignition hot to turn on the fuel pump. It was from inside the car which gets turned off when you crank on the engine.
Sounds like your problem pablo.Prob 2
High idle and extremely loud hissing noise. Pretty sure its the iac controle because it doesn't click at all when i turn on the engine. Gonna try to reset it and check wireing... I looked at some other post with the same problem.
answer. ? what do you think
prob 3
Linkage binds and won't seat half time. Works fine with motor off. Must be manifold vacume sucking on the blades or somthin
answer?
Prob4
Linkage adapter I made sucks.
Answer.
Switch majors because I don't believe someone this stupid should not be an engineer. Linkage goes to wot throttle perfect just won't seat half the time and is really hard to push the pedal for the first 25% of the throttle.
Prob 5
Drop base air cleaner won't fit.
answer
Buy a non drop base
If I can't fix all this in an hour or so tonight i'm gonna have to swap the carb back on. I gotta get it runnin tonight. The big problem i'm having is figuring out what the loud hissing noise is. I'm pretty sure there is no vacume leak. This hiss is so loud it's almost defening. Is it possible to run without a IAC if i set the idle screw up enough? All that put aside it revs like no carb I have ever played with and sounds strong, got blm's in the ball park in 2 burns. Just can't drive it.
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From: Charleston, SC
Car: 91 Camaro Vert
Engine: 02 LS1, HX40
Transmission: 2002 LS1 M6
could the hissing be the noise of the air sucking on the throttle butterflys extra hard because of a broken IAC?
that would account for the IAC, the linkage prob, and the noise....
that would account for the IAC, the linkage prob, and the noise....
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Joined: Feb 2002
Posts: 2,663
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
No, I initially thought the same thing and just stuck my finger in there with the motor runnin and tried to block the air going around the sides of the throttle plates and it didn't change the noise at all. I just read some post that gave me some ideas on what the problem is. Seems like a stuck iac will cause a hissing noise. Gonna try it tonight and see.
edit: I just read some where that 305's have the blue wires swapped on the iac. Is that the sensor or the ecm thats swapped?
edit: I just read some where that 305's have the blue wires swapped on the iac. Is that the sensor or the ecm thats swapped?
Last edited by BMmonteSS; Oct 27, 2003 at 09:09 AM.
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Car: 1992 camaro rs 97 yoyota camry
Engine: lo3 carbed
Transmission: t 5
i think it was on the sensor... there was a post a couple of weeks ago about it... also my tbi always hissed... because of the air getting sucked in. try spraying carb cleaner around the base and see if you have a vac. leak. also i use a non drop base they are real cheap i paid 10 bucks for mine!!! it raises just slightly! but looks good on there!
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Joined: Feb 2002
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
I'm deffinetly looking towards the wireing on the iac as the culprit of the high idle. I'm guess it could also be the reason for my hissing. Just to put the hissing into perspective it is so loud I can hear it above my 3 in exhaust that dumps at the rear axle. I've left the brake booster hose off before and it doens't even come close to this .
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From: Moorestown, NJ
Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Have you adjusted the min air yet? The loud hissing you hear is normal. TBI systems are very loud, especially at idle. You could also have a bad IAC as well. With an air cleaner on it its not so bad. As for the linkage, if the pedal is fine except when the engine is started, then thats a good sign that the area on teh tbi base around the shaft is probably excessivly worn and causing the throttle blades to bind up on the walls of the bores. It probably needs to be rebushed. You can check this by firmly moving the throttle shaft around and feeling for play.
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Thread Starter
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Joined: Feb 2002
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
Well I got it runnin.....sorta. The Iac is bottomed now and it still hisses but not as bad. Had to turn the idle up manually to get it to idle. It barely idles. jumps around really bad, kinda like it's peg rich and then goes peg lean just a couple of hundred rpm's later. Once your movin it's ok. Like barely drivable but the idle is all messed up. I'm runnin 90 pound injectors at 16psi, bpw is set at 94 and i've been making rather large changes to the ve curve and it doesn't seem to making much difference well not a positive diference. I really need a ve curve that is setup for a performance motor and then play with my bpw untill it's in the ball park. Anyone care to post one? It would really save me a ton of time. I'm startin to think the ecm can't run the injectors slow enough to get this thing to idle. Let me know what you think I really need this thing drivable in a day or two.
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Car: 1992 camaro rs 97 yoyota camry
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are you running a 350 engine because it may be just me but 90 pound injectors at 16 psi sounds excessive!!!!!
i think the fuel sould be set around 8-12 psi from the factory and i think the 305 uses 40 or 50 pound injectors...??? i can't remember off the top of my head though someone else help me out. but i think 90's are way too much.
i think the fuel sould be set around 8-12 psi from the factory and i think the 305 uses 40 or 50 pound injectors...??? i can't remember off the top of my head though someone else help me out. but i think 90's are way too much.
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Joined: Feb 2002
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
ohh they are way excessive for a 350..just wanted to see if i could get the ve curve low enough to run that much pressure so it would have a good spray pattern. I'm gonna lower the pressure to 10psi and have another go at it. I really shouldn't have started this with out having enough time to really get it ruffed out. I was prepared to drive it getting 5 mpg till i got it tuned half way decent but it's looking a little iffy right now.
p.s. Any one know when the injectors go "async" I think thats what it's called, like when only one injector fires I could be completely lost on this one though. Could be why it's bouncing like it is.
p.s. Any one know when the injectors go "async" I think thats what it's called, like when only one injector fires I could be completely lost on this one though. Could be why it's bouncing like it is.
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From: East Windsor, NJ, 08520
Car: 2002 Harley Nightrain
Engine: twin cam 88ci
Transmission: manual
could be the 16psi thats making the hissing sound, mine's about that much (cold) with 305 injectors and it hisses but runs great.
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
there seems to be some confusion on the loudness of this wistle...anyone ever hear a weaner wistle, you know the hot dog whistle..... well take that and run 90 psi of air through it. You can't talk over it with the hood up. It's gotta be a vacume leak or somthin.
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From: Park City, UT
Car: '92 Corvette, '89 1/2-a-'Vette
Engine: LT1, L400
Transmission: ZF6, T5
Axle/Gears: 3.45, 3.31
Different injectors
I think 90 pph injectors are WAY too big. WAY too big. I'd try 65-75'ers and go from there.
I am running 90 lb at 9 lbs FP. 350 cid. BPW is set at 93. seems to run fine. i believe i could have used the 65 lbs but was predicting more HP than I found on dyno. original 65 lb'ers were on car 90K miles so possibly needed replacement anyway. anyway, plenty capacity for future. will move FP to 10 lbs next year and retune. I would hope the spray will look better.
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Joined: Feb 2002
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
ok thats why i'm rich right now, i'm runnin 16 psi at a 94 bpw, i'm headin to the garage to see what i can do
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From: Moorestown, NJ
Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Originally posted by BMmonteSS
there seems to be some confusion on the loudness of this wistle...anyone ever hear a weaner wistle, you know the hot dog whistle..... well take that and run 90 psi of air through it. You can't talk over it with the hood up. It's gotta be a vacume leak or somthin.
there seems to be some confusion on the loudness of this wistle...anyone ever hear a weaner wistle, you know the hot dog whistle..... well take that and run 90 psi of air through it. You can't talk over it with the hood up. It's gotta be a vacume leak or somthin.
Thread Starter
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Joined: Feb 2002
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
:lala: :lala:
Whoo Hoo :lala: :lala:
sorry just had to take a victory lap....So got most of the problems fixed and took her out on her maiden voyage. She runs some where between dog pooh and baby splatter but she runs. Thats all i wanted out of it. Long road ahead tuning the beast but it looks like i'm not quite as stupid as I look.The whistle was a vacume leak. My home made adapter plate is too thin (1/4 aluminum not enough I guess) and the thin gasket I was using was acting like a you guesses it a whistle. Got that fixed then the (insert explicit language here) oil pressure guage sprung a leak and required a good hour to fix. After that i lowered the fuel pressure as low as it would go only got it down to like 11 pounds. Took a good hour making a base bin from a 454 chip and a v-6 chip. Thats all it took.
At least i can get started on the tuning now. For some dump reason the cpu was thinking it was lean when i got her first started which it wasn't because I started halucinating from the fumes. Once I got it on the road and it cleared out the 5 gallons of fuel that was in the motor it started reading peg rich. Like it pegged my blm's at 90 somthin. So at least I know what it's doin now. Just wanted to thank you guys for helpin out.
Whoo Hoo :lala: :lala: sorry just had to take a victory lap....So got most of the problems fixed and took her out on her maiden voyage. She runs some where between dog pooh and baby splatter but she runs. Thats all i wanted out of it. Long road ahead tuning the beast but it looks like i'm not quite as stupid as I look.The whistle was a vacume leak. My home made adapter plate is too thin (1/4 aluminum not enough I guess) and the thin gasket I was using was acting like a you guesses it a whistle. Got that fixed then the (insert explicit language here) oil pressure guage sprung a leak and required a good hour to fix. After that i lowered the fuel pressure as low as it would go only got it down to like 11 pounds. Took a good hour making a base bin from a 454 chip and a v-6 chip. Thats all it took.
At least i can get started on the tuning now. For some dump reason the cpu was thinking it was lean when i got her first started which it wasn't because I started halucinating from the fumes. Once I got it on the road and it cleared out the 5 gallons of fuel that was in the motor it started reading peg rich. Like it pegged my blm's at 90 somthin. So at least I know what it's doin now. Just wanted to thank you guys for helpin out. Thread Starter
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Joined: Feb 2002
Posts: 2,663
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From: Buckhannon, WV
Car: 84' Monte
Engine: 350
Transmission: 700-r4
Axle/Gears: ferd 9" posi 3.50 gears
Just another update. First couple of chips got her runnin pretty decent. Still rich but I have a good bit more room for adjustment. Ohh by the way I redid the throttle linkage and she works nice and smooth now. This cam isn't all that hard to tune around, it's just a little sloppy down round 800 to 1200 rpm's. Should clean up nicely and man does the throttle response blow away the 750 carter I had on there before. Hopefully I can get everything squared away enough to do some full throttle action before long, right now it's a pain to take off in the rain without blowing the tires off so I can't wait to see what she'll do tuned up and on dry pavement
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