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steve1ph
Guest
long time since iv been here. hi im haveing a real rich idle problem. any how i was going to ask what yall think about me taking the 36# back out and putting the 24# back in. mic need any 36#?
WhalePirot
Well-known member
Steve-
May I suggest taking a look at: http://www.jimsperformance.com/tech.html to pick the right sized injector. You will see that the size is a funcgtion of the power your engine produces.
From there, the proper programming of your ECM will be the only right way to get the proper mixture, unless you have another issue with the idle, only, and the associated components.
May I suggest taking a look at: http://www.jimsperformance.com/tech.html to pick the right sized injector. You will see that the size is a funcgtion of the power your engine produces.
From there, the proper programming of your ECM will be the only right way to get the proper mixture, unless you have another issue with the idle, only, and the associated components.
Mad-Mic
Gone but not forgotten
nope don't need not 36 pounders till i do my 434 stroker motor next year 
but it wouldn't hurt to throw them back in. i remember we discussed this over email. what size motor do you have? if i remember correctly it's a stroker motor. what A/F ratio is it running at? hard to really make a decision on it with out knowing "How Rich" it actually is.
checking the plugs? are they burnt black? soaking wet? this will atleast give us some indication "How Rich" it actually is running. what pressure are you running now? if it's in the low 30 range put the 24's in and start back out at 47 psi and work your way up but don't go past 50 psi. IMO 50 psi is the limit of the injector for proper spray. now if your in the mid 30 psi range to high 30 psi range you could try and add alittle more timing 2 degrees at a time. are you running an aftermarket coil? if not try one. this might help lean it out alittle more along with the timing. regap plugs to .047 for better spark.
have you been driving the car alot since you had it back? if so check the cat converter. it might be clogged up from running so rich.
i hope this helps and let us know what you find!
BTW Steve i got TPiS long tube headers now thanks for the Y pipe! the front Y pipe got me down to a 13.26 last year and i could of got a 13.0 i think if the snow would of stayed away a little longer 
with the long tubes i've picked up about 3 mph but only 1 tenth so far in crap air. i'm knocking on 12's and hope to land a 12 second slip in the next week or so 
but it wouldn't hurt to throw them back in. i remember we discussed this over email. what size motor do you have? if i remember correctly it's a stroker motor. what A/F ratio is it running at? hard to really make a decision on it with out knowing "How Rich" it actually is.checking the plugs? are they burnt black? soaking wet? this will atleast give us some indication "How Rich" it actually is running. what pressure are you running now? if it's in the low 30 range put the 24's in and start back out at 47 psi and work your way up but don't go past 50 psi. IMO 50 psi is the limit of the injector for proper spray. now if your in the mid 30 psi range to high 30 psi range you could try and add alittle more timing 2 degrees at a time. are you running an aftermarket coil? if not try one. this might help lean it out alittle more along with the timing. regap plugs to .047 for better spark.
have you been driving the car alot since you had it back? if so check the cat converter. it might be clogged up from running so rich.
i hope this helps and let us know what you find!
BTW Steve i got TPiS long tube headers now
thanks for the Y pipe! the front Y pipe got me down to a 13.26 last year and i could of got a 13.0 i think if the snow would of stayed away a little longer with the long tubes i've picked up about 3 mph but only 1 tenth so far in crap air. i'm knocking on 12's and hope to land a 12 second slip in the next week or so - Thread starter
- #4
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steve1ph
Guest
mic. rich, im rich,to rich.
mic, i left out a few details since we last mailed. after i put the super ram with 58mm tb and 36# injectors on i was getting an eye burning idle at 900 rpm. reset the timing now it ran rich untill the loop ( 10 or 15 minutes or 5 or ten miles) then was ok. oh yea with this setup i went 600 miles on a full tank of gas. do you belive it? from dallas to big spring texas and back at $1.65 a gallon. im thinking ram air, headers, gutted cat, and 6th gear was in my favor. any how just recently the car would back fire when i would put my foot in it. ie: plug wires. i have msd 8.5 new. then it got to where it would pop or back fire randomly during idle. which is where im at now. i replaced all the wires with the old taylors i had and still the same random back fire. not wires. you touched on the plugs being black which is true. which brings us back to running rich. fouled plug. or other sensors telling the ecm to dump more fuel. anyhow this weekend im leaning towards changing the plugs if that works good. then im taking the 36# injectors out which are for sell.
mic, i left out a few details since we last mailed. after i put the super ram with 58mm tb and 36# injectors on i was getting an eye burning idle at 900 rpm. reset the timing now it ran rich untill the loop ( 10 or 15 minutes or 5 or ten miles) then was ok. oh yea with this setup i went 600 miles on a full tank of gas. do you belive it? from dallas to big spring texas and back at $1.65 a gallon. im thinking ram air, headers, gutted cat, and 6th gear was in my favor. any how just recently the car would back fire when i would put my foot in it. ie: plug wires. i have msd 8.5 new. then it got to where it would pop or back fire randomly during idle. which is where im at now. i replaced all the wires with the old taylors i had and still the same random back fire. not wires. you touched on the plugs being black which is true. which brings us back to running rich. fouled plug. or other sensors telling the ecm to dump more fuel. anyhow this weekend im leaning towards changing the plugs if that works good. then im taking the 36# injectors out which are for sell.
WhalePirot
Well-known member
As Mic said---UR injectors are too big
Steve-
Pardon me for jumping in.
Using the formula in the above link, my 406, at about 550hp, uses 30pph Bosch injectors at 47psi. Opinions among experts vary as to using higher pressure and smaller injectors, or vice versa. Low vacuum, read by a MAP sensor, will signals the ECM of a more open throttle than actually exists, hence it demand more fuel, producing a run rich condition. Associated with all of this is black/fouled plugs, popping, as the unburned fuel explodes in the exhaust, black exhaust, etc.
Once the injectors are properly sized, fuel pressure and ECM pulses must be adjusted for proper A/F ratio. While there is some 'art' to this, the best way is to to judge how radical the changes were. Fuel pressure, while certainly essential to proper tune, is only part of the equation and is limited, high and low, by proper spray patterns and such.
The ECM's block learn capability is limited, but reading these adjustments to the fuel tables (+/-128 max), as it tries to optimize the burn, tells the full story. Too low vacuum can easliy exceed how lean the ECM can adjust, as I saw on my slightly modified, Crossfired, L83 and again on this port injected 406. The fairly radical, hydraulic roller camshaft on this 406 demanded new programming of my ECM's chip, in both advance and fuel delivery.
Once fuel pressure is set, a rather 'gross' and broadband adjustment, proper programming of your ECM will be the only right way to get the proper mixture under all driving conditions. Further adjustment of pressure after the ECM is dialed in, will cause the ECM to try, again, to optimized it.
Ignition components, such as a multi spark discharge box can burn more fuel, but also mask problems in the fuel area and those with failing wires or plugs. The stock system, properly maintained, will deliver more than adequate spark, unless one boosts the intake charge with a blower or exceeds 7000 rpm or so.
Mic is right again to suggest going back to the 24# sprayers. You might consider returning to the stock TB, too, unless you turns such high revs as to need all that air. A 52mm BBK serves this 406 well, up to redline.
I submit that your CAT is working very hard in cleaning up your exhaust, but cannot do so until totally warmed up, as your drive to the loop suggests.
Probably not what you want to hear, but the truth, as best I know it.
Mike
Steve-
Pardon me for jumping in.
Using the formula in the above link, my 406, at about 550hp, uses 30pph Bosch injectors at 47psi. Opinions among experts vary as to using higher pressure and smaller injectors, or vice versa. Low vacuum, read by a MAP sensor, will signals the ECM of a more open throttle than actually exists, hence it demand more fuel, producing a run rich condition. Associated with all of this is black/fouled plugs, popping, as the unburned fuel explodes in the exhaust, black exhaust, etc.
Once the injectors are properly sized, fuel pressure and ECM pulses must be adjusted for proper A/F ratio. While there is some 'art' to this, the best way is to to judge how radical the changes were. Fuel pressure, while certainly essential to proper tune, is only part of the equation and is limited, high and low, by proper spray patterns and such.
The ECM's block learn capability is limited, but reading these adjustments to the fuel tables (+/-128 max), as it tries to optimize the burn, tells the full story. Too low vacuum can easliy exceed how lean the ECM can adjust, as I saw on my slightly modified, Crossfired, L83 and again on this port injected 406. The fairly radical, hydraulic roller camshaft on this 406 demanded new programming of my ECM's chip, in both advance and fuel delivery.
Once fuel pressure is set, a rather 'gross' and broadband adjustment, proper programming of your ECM will be the only right way to get the proper mixture under all driving conditions. Further adjustment of pressure after the ECM is dialed in, will cause the ECM to try, again, to optimized it.
Ignition components, such as a multi spark discharge box can burn more fuel, but also mask problems in the fuel area and those with failing wires or plugs. The stock system, properly maintained, will deliver more than adequate spark, unless one boosts the intake charge with a blower or exceeds 7000 rpm or so.
Mic is right again to suggest going back to the 24# sprayers. You might consider returning to the stock TB, too, unless you turns such high revs as to need all that air. A 52mm BBK serves this 406 well, up to redline.
I submit that your CAT is working very hard in cleaning up your exhaust, but cannot do so until totally warmed up, as your drive to the loop suggests.
Probably not what you want to hear, but the truth, as best I know it.
Mike- Thread starter
- #6
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steve1ph
Guest
mister whale, do you burn eproms? as well thanks for all the advice sounds good to me. going to do the plugs this weekend if that works then of course the sram will have to come off to get to the injectors.
- Thread starter
- #7
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steve1ph
Guest
spark plugs
what spark plugs do yall use. im running factory delco. recomend?
what spark plugs do yall use. im running factory delco. recomend?
Mad-Mic
Gone but not forgotten
i run AC Delco Rapid Fire plugs with an .047 gap to help on burn. when you change the plugs and put the #24 injectors back in, if it continues to run rich then your cat is toast. running super rich for a long amount of time will clog the cat and make the car run super rich.steve1ph said:
also you might want to talk to -=Jeff=- who is a moderator for the C4 section about burning you a chip. i recommended him before. he will work with you on your tune and will reburn the chip upto 2 times for you for 175 bucks which is pretty cheap considering some charge as high as 350 bucks for a cookie cutter chip.
great info Whale! glad Jim's shop is right around the corner from my house
Mad-Mic
Gone but not forgotten
is your car a 6 speed with speed density? i *might* know someone that is selling not only a level IV chip from TPiS but also the ecm from a 90-91 6 speed car if your interested. i think he was asking 200 bucks. i'll have to check. with the chip on a mini ram setup with afr heads and ZZ9 cam the car ran 10.8's.
if not talk to -=Jeff=- cause i know he does good work on chips also.
if not talk to -=Jeff=- cause i know he does good work on chips also.
- Thread starter
- #10
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steve1ph
Guest
well proble going to get flamed for running with no cats. actually i have one and it came apart long ago so i unhooked the back y and blew all the inards out. now there is no ozone protection. after the car warms up it does not run rich. but iv noticed that doing about 70mph and stomp it i get the black unburned fuel puff. let me give you a quick history. 1st parts list. stroked 383, big cam, all msd ign ( 6a, 8.5 wires and coil, stock dist). hooker ceramic coated long tubes, breathless ram air, borla cat back, sr intake all three parts, 58mm tb, 36# injectors. stock heads, stiffer springs, stock rocker ratio, stock rear end and tranny( 6speed). a super chip eprom that was in the car when i bought it. long story short after i put the sram, injectors and tb on about 2 months after i stroked it. at that point the car would idle 900 ( super rich) then jump to 2000 and stay there (air fuel ratio ok) . got annoyed about the idle jump and pulled the plug on the air idle control valve while it was closed or mostly and plugged it in to the one that i took off the factory tb. then just adjusted the idle with the butter fly screw. rigged or what? but still had the rich burn during warm up. now the popping. we are talking 6months laps between sr install and the popping. kick that around and let me know what you think. going to do the plugs on friday.
-=Jeff=-
Well-known member
the 36# are a bit big if the Chip is not changed to compensate. I actually run 30# in my minirammed 357 but I have tuned it to not be rich anymore. I would almost stick to the 24# injectors for your set-up. I was going to build my SBC400 which is why I have the 30# but that project is on hold indefinitely.
WhalePirot
Well-known member
I wish I could burn chips. There is a market for it, but no, I do not. Such is a talent I have not developed, which entails in-depth knowledge of how engine control and performance works: mixture and timing, in detail and as related to output and driveability problems. The euiipment and know-how of reading and adjusting fuel tables is not rocket science, but an endeavor for others, here.
I have used and bought from Jim. He is great and always seems to find time to help. I am slowly finding experts in SoCal. Hot cars and the guys who were really into them, have gone to boats, due to SMOG laws. I feel lucky to have found one guy, who would take the time, to custom program my ECM. He did, what was termed, impossible, by many 'pros'.
I found my original CAT plugged, when the engine could not reach high RPMs. It was due to a long standing rich condition.
I was quite lucky to have a brother who used to work at the factory and he got me a new CAT, as part of his 'bennies'. They were allowed one/ywear, for any car. It sat in the garage for years, waiting for me to need it. I had run a 'hi-flow, aftermarket CAT, with small problems, but this stock replacement seems to NOT hinder my car at all. I found no seat-of-the-pants performance difference between the hollow test pipe and the factory CAT, so I comply, gladly, with the law and have a tube for a future telescope project!
I have used and bought from Jim. He is great and always seems to find time to help. I am slowly finding experts in SoCal. Hot cars and the guys who were really into them, have gone to boats, due to SMOG laws. I feel lucky to have found one guy, who would take the time, to custom program my ECM. He did, what was termed, impossible, by many 'pros'.
I found my original CAT plugged, when the engine could not reach high RPMs. It was due to a long standing rich condition.
I was quite lucky to have a brother who used to work at the factory and he got me a new CAT, as part of his 'bennies'. They were allowed one/ywear, for any car. It sat in the garage for years, waiting for me to need it. I had run a 'hi-flow, aftermarket CAT, with small problems, but this stock replacement seems to NOT hinder my car at all. I found no seat-of-the-pants performance difference between the hollow test pipe and the factory CAT, so I comply, gladly, with the law and have a tube for a future telescope project!
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