So I have a pretty basic set up. 355ci lt1 with cc503. It was running OK with out a tune. Then its started running extremely rich. With all the fuel in the oil I figured my injectors were leaking. So I bought these 0280155831. Because they were rated 28lbs @3bar. I didn't feel like my engine was making enough power to use bigger ones yet. Well after installing the car will only idle. I can't drive it, so I paid for a full performance tune on the 16th, then mailed it out on the 17th. He received it on Tuesday n still hasn't tuned it. Then says he doesn't know if it'll work with these injectors. I tried to exchange them for the ford 30's like everybody else but its been too long so I'm stuck with these. He tells me I'll get it back early next week. Is there something I'm missing? I thought the tune was for the injector #'s not what car they were originally intended for. They are Bosch injectors...what's so different about them? I'm just trying to get some clarity before I start cussing people out. I just feel like if I didn't pay for the tune all ready I would get more timely treatment. Especially since I told him last week my family car was down n I needed this asap.

I hope atleast you have upgraded from the 870 ecm to the 165 ecm. the Volvo 28#hrs will work you could even run 30s . Everyone has there own process for tuning. I all was start with a base tune I do myself then have a datalog submitted so I can make corrections. just changing the injector constant to help with ecm control is a huge difference and may even make the engine run lean with the 28s until correction can be done to the maf tables.

If this is an lt1 you did a mail order from one of the major tune companies?

Injector type doesnt really matter, a good tuner will make it work. However a mail order doesnt mean tuned. Got to find a local person if you can to work driveability. Mail order ppl should have a file that works close enough tho esp if you used pcmforless. Double check you have no mechanical issues causing this and work with the tuner to try something different.

Sorry, missed the lt1 part opps, what justin said live is Always better.

Yes I am getting a mail order, and it is a big mane tuner, but I'm not happy rite now and im not into name bashing so I don't feel like mentioning the company name will do anything but cause me more problems, especially on a topic that I'm not well rounded on. I understand live is better, but right now I just need my car back on the road. I have checked for mechanical issues, and it seems my rebuild is holding together fine. I did replace the MAP pigtail. I can't seem to get a UART signal when I wired the dlc. So live is out of the question for now anyway. I gave up the dlc because the car was running ok. And I was in the middle of relocating across country. Now I'm here and settled so I'm back at it. Before I replaced the injectors I checked o² sensor, MAF, map IAC, TPS manually. Found my tps had a dead spot which improved throttle response. Also went with NGK tr6's and changed the opti because my rotor had a very small amount of play. I also checked my wires while I was at it and they looked good. All of this help cold start. But was still running REALLY rich. Through reading on this forum I read that without a tune and my cam I'm most likely washing down my cylinders. So now I'm here. The only thing I feel like I overlooked was my temp sensor. But I feel like that would really only cause me problems during closed loop. And that should include idle not just acceleration. He finally got back to me n says he's concerned about how the computer will controlled the injectors...I'm guessing he's referring to the impedance values rite?? But they are rated @12.5-14.5 ohms....which indicates they are high impedance like the factories rite? I feel like he's spinning me to buy time, since I was told/read this was supposed to be done with 2 days of receiving the pcm

Different injectors have different operational properties. I'm not going to get into the theories of inductance, capacitance and impedance changes making two different injectors of same flow rating operate differently, but suffice it to say, they do. Then there is the physical properties, like pintle or disc that make a difference, then add in the type of spray pattern they have, will change how they work in an engine. There's a lot more to an injector than just how much it flows when it comes to getting a good tune.

Six_shooter, thanks for not going too deep/over my head with it. But I figured the basic design would play a factor. Which is why I chose to stay with a 4 hole design (same as factory) instead of a pintle. Which honeslt I would prefer. I would rather have an injector stick open than clog up. But I planned on getting a mail order tune/flash first because I have really made up my mind on what ignition system I want for the long run I.e distributor, or CNP. But I do know I wanna burn up a few sets of tires to and from work while I'm deciding. And I'm confident this is the last peice of my puzzle holding me back

Yeah injectors design can change fueling but to alter the fueling so much that the car is undriveable, when the base tune supposively works on same combo with different brand injectors of similar size, to me is not a reasonable explaination. You are talking an insane amount of fuel difference. I have tried siemens 80lb then moved to fic 127's on same tune, just accounted for injector and it was running. Ran rich at first, had to lean some items out but a motor will idle anywhere from 10's air fuel to 16-17's air fuel and it will also drive part throttle all in between those ratios as well.

I think the tune needs looked at again. It shouldnt be that far off imo. Thats assuming everything else is ok and no mechanical issues etc

Oh boy.....well with the stock 24/22 lbs (not sure what came on road masters) I had to shut the injectors off to start it, and feather the throttle for 1-2mins before the idle would level out. It stayed erratic until it went into closed loop then ran good just smelled REALLY rich n puffed brown/black smoke when I revved it to 5500. After I changed all the parts I mentioned above and went to a walbro 255 I changed my oil with royal purple(amazon deal), fired it up n had similar problems. Went back out the next mourning n checked the oil....it was like I dumped a gallon of gas in it...biggest waste of oil! This is why I got new injectors in the 1st place. Now after the injectors it doesn't need as much feathering as before to idle on its on. But it sounds like its drowning when accelerating. I'd be willing to bet if I had regular copper plugs in it they would fowl out. So the only thing I could think was that it needed tuned. I was under the impression that the extra air flow across the maf form the cam and bigger ci would make the pcm increase the....open time/duty cycle? Of the injectors to avoid lean condition. I thought it would do the same but worse with these injectors since the pcm doesn't know they are bigger. I know the o2 should play a factor in this also but I would think emission would take the back seat to engine preservation. Sorry about the novel but I'm trying to paint the whole picture. This will be the last time that I deal with a tuner that doesn't offer phone support. Smh (insert slap myself icon)...

So to finish this thread, mail order tune solved all problems! No need to feather throttle to get it started, no hesitation, no smoke AT ALL, throttle response is night and day, no drowning, quiet backfire during acceleration...its like a whole different car!

What did you do different? Use a new tuner? Or work the issues out with the old tuner?

I stayed with the same tuner because he already had my pcm. My problem with him was minimal communication. 1 email a day, the 1st one was, I'm not familiar with the injectors, it may not work....that put me on edge immediately, then with no reassurance other than, "if it was me I would try to exchange for ford 30's"...I already had to agree to no liability when filling out the order sheet. He has ALOT of positive review on a few fbody forums so I thought it was worth the risk. I had to pay for priority return shipping, but didn't get any tracking information....not even an email saying its been sent out. Even after I repeatedly sent emails asking when/if it had been shipped yet because my family car was down so we were bumming rides and I needed to know how long I needed to schedule them to make thing as convenient as possible for our friends. After its all said and done I'm very impressed with the tune, no arguing that, but the customer service fuc**** sucked! Next time I will pay the extra and go with pcms forless...at least they could pick up a phone, and save all the emails in 20 mins. I'm a tech. Myself so I understand people constantly calling and tying up work time with ladidah conversation. But me asking..seemingly valid questions and come to find out O'Reilly gave me the wrong year pcm so now my knock sensors are wrong, I think a phone call is in order. That's gonna change more than a couple things in my electronic parts selection...it just wasn't a good move to put me on edge so quick then take a week to do something he was would be done in 1-2 days. Maybe he was researching my injectors but he could have told me that...

And even better....I noticed today my home made security system isnt working any more because my vats has been disabled when I didn't request that.....this isn't the best situation because Miami has ALOT of stolen car cases and these cars are really easy to steal