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305 TPI running rich

Old 09-25-2014, 04:57 PM
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305 TPI running rich

I bought my firebird about a year ago and the po said that they had had 24# injectors installed and now it runs rich. rich enough for smoke to come out the exhaust when starting the vehicle as well as when under a decent amount of load. I don't think that's normal even with the heavier fuel injectors and I'm curious if there is a good solution without buying different injectors.

I've considered adjusting the timing, but that scares me as the indicator at the harmonic balancer only goes to 12 degrees before TDC and I don't know how much I should adjust it anyway to allow greatest performance and safety. I have also noticed that when I get up in RPMs and let off the gas, I hear like a gurgling sound in the exhaust, don't know if that is in any way related.

I could really use a solution as I don't think the car will pass inspection without that fix (due to smoke coming from exhaust). I appreciate any assistance I can get with this.
Old 09-25-2014, 05:10 PM
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Re: 305 TPI running rich

Originally Posted by corey8084
I bought my firebird about a year ago and the po said that they had had 24# injectors installed and now it runs rich. rich enough for smoke to come out the exhaust when starting the vehicle as well as when under a decent amount of load. I don't think that's normal even with the heavier fuel injectors and I'm curious if there is a good solution without buying different injectors.

I've considered adjusting the timing, but that scares me as the indicator at the harmonic balancer only goes to 12 degrees before TDC and I don't know how much I should adjust it anyway to allow greatest performance and safety. I have also noticed that when I get up in RPMs and let off the gas, I hear like a gurgling sound in the exhaust, don't know if that is in any way related.

I could really use a solution as I don't think the car will pass inspection without that fix (due to smoke coming from exhaust). I appreciate any assistance I can get with this.
305s take 19 lb hr. and you might want to ditch those and fix it right. as for the smoke ,no way will it pass like that. HCs will be through the roof.
Old 09-25-2014, 05:19 PM
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Re: 305 TPI running rich

yeah, I know the stock are 19# and the po increased it for performance. if possible, I would rather adjust something than pay to replace the injectors, if that makes sense. I know, I'm trying to be lazy and cheap, please forgive me.
Old 09-25-2014, 06:22 PM
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Re: 305 TPI running rich

Originally Posted by corey8084
yeah, I know the stock are 19# and the po increased it for performance. if possible, I would rather adjust something than pay to replace the injectors, if that makes sense. I know, I'm trying to be lazy and cheap, please forgive me.
ok, we forgive you for being lazy and cheap. but the CARB wont. call south bay and get yourself some 19 lb hr injectors and move past this gaffe.
Old 09-25-2014, 07:07 PM
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Re: 305 TPI running rich

Carb as in carburetor? Or did you mean car? Because one of those I don't have.
Old 09-25-2014, 08:20 PM
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Re: 305 TPI running rich

Originally Posted by corey8084
Carb as in carburetor? Or did you mean car? Because one of those I don't have.
Californication Air Resourses Board, get it?
Old 09-25-2014, 09:06 PM
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Re: 305 TPI running rich

Very sorry. I need to update my profile. I don't live in california anymore. Louisiana just doesn't want to see smoke. They don't care so much about emissions.
Old 09-26-2014, 08:29 AM
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Re: 305 TPI running rich

rusty vango is right. 24's are a bit on the large side for the 305. I know you would rather not spend the money, however if we can help you in anyway, please don't hesitate to give us a shout.
Old 09-26-2014, 09:14 AM
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Re: 305 TPI running rich

well then, if I'm going to be forced to spend money, I would like to future proof things a little bit. another big reason I wanted to keep the 24# injectors was because I plan to do a swap and put a 357/383 in it. to my understanding the 24's aren't out of the scope for that engine. what size should I consider if I want something that's still viable after the swap? (I would like to not have to buy injectors twice, if possible) I know I'm trying to be cheap and I hate it, but I just got out the Marines and am a full time student so my income is a little limited.
Old 09-26-2014, 10:01 AM
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Re: 305 TPI running rich

Originally Posted by corey8084
well then, if I'm going to be forced to spend money, I would like to future proof things a little bit. another big reason I wanted to keep the 24# injectors was because I plan to do a swap and put a 357/383 in it. to my understanding the 24's aren't out of the scope for that engine. what size should I consider if I want something that's still viable after the swap? (I would like to not have to buy injectors twice, if possible) I know I'm trying to be cheap and I hate it, but I just got out the Marines and am a full time student so my income is a little limited.
save the ones you now have for later. but you need 19s for a 305 to run right. south bay is in expensive and worth it.
Old 09-26-2014, 10:14 AM
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Re: 305 TPI running rich

I hadn't thought of saving the ones that are on there already. I am not a smart man. Stupid question: will I see a loss of power when I drop to the 19# injectors?
Old 09-26-2014, 10:41 AM
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Re: 305 TPI running rich

Originally Posted by corey8084
Stupid question: will I see a loss of power when I drop to the 19# injectors?
My guess is it will run better. It's been running rich for so long, the plugs may be fouled, so they might need an inspection also.
Old 09-26-2014, 10:44 AM
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Re: 305 TPI running rich

interesting point. I guess I'm just really worried. I'm an amateur and I don't want to break my toy. but those fuel injectors have been in for at least 2 years.
Old 09-26-2014, 11:00 AM
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Re: 305 TPI running rich

Originally Posted by corey8084
interesting point. I guess I'm just really worried. I'm an amateur and I don't want to break my toy. but those fuel injectors have been in for at least 2 years.
Do a compression check on all cylinders to make sure the piston rings didn't go on you just yet, change your oil and oil filter, and either get the correct 19 pound injectors, or get a custom chip burned for those 24 pound injectors. Stop delaying what needs to be done, otherwise you'll need new piston rings if you don't already need them...
Old 09-26-2014, 11:08 AM
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Re: 305 TPI running rich

quit bullying me! lol j/k. are you saying to do an oil change before the compression check because I just did an oil change (btw, apparently K&N 2002 is not a perfect fit for my car, Mobile 1 M1-111 or whatever fit much better, K&N leaked real bad on this last oil change I did)
Old 09-26-2014, 12:33 PM
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Re: 305 TPI running rich

Originally Posted by corey8084
quit bullying me! lol j/k. are you saying to do an oil change before the compression check because I just did an oil change (btw, apparently K&N 2002 is not a perfect fit for my car, Mobile 1 M1-111 or whatever fit much better, K&N leaked real bad on this last oil change I did)
synthetic oil on a old engine is just asking for leaks everywhere. and switching to 19s will make it more efficient in its use of fuel, thusly your MPGs will go up some. and , well , one dosent mention power and 305 in the same sentence!
Old 09-26-2014, 12:39 PM
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Re: 305 TPI running rich

Hmm. How about 302 and power? Wooh Ford! Haha. I kid, don't shoot me please. MPGs were never much of a concern to me, if they were that important I would have bought a civic.
Old 09-26-2014, 02:31 PM
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Re: 305 TPI running rich

Originally Posted by corey8084
Hmm. How about 302 and power? Wooh Ford! Haha. I kid, don't shoot me please. MPGs were never much of a concern to me, if they were that important I would have bought a civic.
touché !
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