Injectors

[Big_Z]

Well I just put some 30lb Injectors in my Z34 with the coil packs & wires. The car has a Superchip in it. why would it run ruff with black smoke? And it also only hits 3500rpm then it brakes up . Can anyone help me??????

[your_I.D.]

overfueled

[Kohburn]

WAY to much fuel
put the stockers back in or reprogram the chip

[Big_Z]

well it has a super chip won't that help?

[pocket-rocket]

No, the super chip doesn't know you have massive amounts of fuel being dumped in because you never had the chip reprogrammed for them... Right now it think's you have stock injectors, and it can only pull fuel so far to try to compensate for the extra fuel. Think of it as taking a stock 302ci (Mustang 5.0) and tossing a Holly 750 double pumper carb on it without putting in other new goodies to take care of the extra fuel and air the new carb can pass. Leave them in there long enough and you could run the risk of washing the oil off of the cylinder walls which = bad news for you and your engine.

[RednBlack]

A/F ratio definately needs adjusted. Not sure if Superchips are tunable. Ask sappy. He fries his own chips. Something else to consider. with more fuel, you need more air. Have you done anything about that?

Pocket...What are you doing posting? You have a year yet! :P

[SappySE107]

I wouldn't waste my time with that chip, and I certainly wouldn't be running those injectors without some form of boost.

[OldSkoolGP]

That, or at least have it reprogrammed to lower that injector pulse width a lot more.

[pocket-rocket]

Pocket...What are you doing posting? You have a year yet! :P

I thought something was wrong with my calender.... and away I go!!!

[Big_Z]

Thanks you guys are helping ALOT

[Scott205]

30lb/hr are probably exceeding what the computer can handle at its minimium rate of bandwidth. If your headers and exhaust are still stock (no port polish) it is probably struggling to get air and so your Stoicometric ratio is horrible. More gas doesn't mean faster unless you have more air and more control. I am putting 26lbs in my new crate motor, have to see how that goes.

[Big_Z]

now what do you mean by "crate" moter??

[Scott205]

Crate engine

now what do you mean by "crate" moter??

I mean it was bought from a GM dealership (through ebay) brand new 0 miles, not rebuilt, and they package it in a crate. GM still sells quite a few EcoTech and many V8s as a crate motor. They come with Heads, and most of the sensors (plus spark plugs, oil filter) already installed. You just need the intake manifold, plenum, exhaust manifolds, and your accesories (a/c, alt, power steering pump) and you have a brand new, not rebuilt engine.

[Scott205]

Ok, well, engine is in, sounded like it had a miss.. played with it for a day and found out when we pulled the harness on #2 injector there was no change in what almost sounded like a miss. A good mechanic friend of mine suggested to have the flowed, took them over, after 40 bucks, found out that one was flowing less than half and they were poorly matched. So i have new ones ordered (should have been here today, not making me happy) and i will have them flowed. My lesson of this has been pay to have someone flow test them if you want good performance, order 2 sets, send the worst back.

More news later. But 26lbs didn't make it black, curious to see how a better set will do.

[fieromadman]

stock injectors have a dual conical spray pattern anyhow, putting aftermarket injectors in might tweak the A/F even if they flow the same......