OK, so no matter what people tell you, the stock injectors are not enough for your set-up. Now you mention that Ion's tune was way off. Not that it can't happen, but to be "way off" is pretty rare for Ion. More than not there is something amiss with your car, maybe a fuel pump or something else is being over looked. This is what I have seen many times before and the 1st tuner is blamed. Hardly anyone comes back after sorting the bugs out and says I was wrong, or the new guy I'm working with made a mistake.
Good luck with the car, but don't be bashing someone before you know the whole story.

 

It is VERY common for people to not notice their fuel pump is dying until they hit a dyno.

Happened to me personally...was going lean up top - found out the fuel pump was dying and couldnt keep up. New full racetronix kit fixed the problem 100%.

Mileage is sometimes a good indicator to guess on problems, but to be honest it doesnt really matter - nothing is always certain with cars. If something is going to die on you, it could have 10 miles on it and still bite the dust.

 

Its kinda hard for a mail order tuner to see your fuel pump is on its way out. LOL

 

I've done a lot of research and from what I've gathered, factory injectors are really only sufficient for the factory cam. Even with a baby cam, many people's injector duty cycles are around 95-100%.
Where did you get the information that our 24# are good for 400whp? I've never heard that before...

 

haha, i told him on page one that ions tune was gonna be way off. and the fact its over 100% duty cycle is exactly what i would exspect from his tune given my prior exsperiance. he is not out of injector yet. just pig rich. is going bigger bad. no it will give him room to grow, but not required at this point.

 

given that a mail tuner cant see problems the car has, and the fact that every lt1 ive seen like some totally differant. i dont know how anyone can get away with mail order tuning a lt1. they are very picky beast. i would take it to someone with plenty of lt1 specific hands on tuning.

 

i should have worded that better they max out around 400 hp. well passed 80% duty cycle. The point i was trying to make is that he doesn't need them yet being cam only he isn't even going to clip 350 with that cam. I ran a cc305 (220-230 .510 .510) bigger then his and datamaster only reported 80-81% duty cycle for a milla second before the shift. But i have a new wlbro 255 so my pressure holds rock solid all the way through a pull.

 

Wow lots of people hating in this thread.


Im tuning the car,and yes i have two mustangs and a el camino...
The cobra is on video on this site going 10.0 at 140 on a stock long block and full weight,i have a 1000 whp f1r fox body and a rat powered 14 to 1 496 pro race fogged 65 elco...All built and tuned by me.



Anyway,i never dynoed his car,nor did i check the injector duty cycle.I know from the stang world that 24s are good to the 340 range at 80% duty cycle,the last time i checked you dont want to go past that mark as the spray pattern turns to ****.And really why take the risk of being at 100% duty cycle and then having to re dyno Again.Im trying to save him money in the long run,as i told him to install his cats as well so again he only has to tune once,yes it only makes a slight difference in the ve table but i like my tunes within 1% across the board.So why not do it right the first time then dog **** it twice to three times.I also told him to not be mad at 320 to 330 with his combo.The comment about get a new tuner was un called for and you have no merit to suggest that to him.I have a very good rep in the local community for pretty much all domestic stuff.Ive done Big stuff 3 AEM FAst and efi live tuner cats and sct for the fords.This isnt my fisrt dance when it comes to tuning,nor my first when it comes to having happy customers and also happy customers that only have to pay for one tune because they have enough injectors and fuel system,i also suggested a pump upgrade when he came in.

http://www.youtube.com/watch?v=mZeJl...e=channel_page

there is the video to my slow stang.Did i say that its daily driven and i drove it 200 plus miles to and from the track,I got the boot before i could get my 9 sec time slip.

 

Also to clear something else up.

I said i hate mail order tunes because imo every car is different,but i never once bashed his tuner,or implied he had a bad tune,that was all him,as he said it ran horrible.

 

I agree 100% thats why i told him to address his fuel system now and be 100% ready to dyno tune his car.And ya i have done a few lt based cars.

 

I know elky and we both tuned my LT1 car it had a mail order i wont name who it was but did 349rwhp fine tuning ended up getting 387 rwhp out of a cc503 midtubes and ported heads 355

https://ls1tech.com/forums/lt1-lt4-m...ble-setup.html

 

Mail order tunes are what they are. Not all of us can trailer a car to the shop for a dyno tune. You start out with a mail order (start-up) tune and fine tune on the dyno. Sometimes you gain 2-3 hp, other times you gain a boatload with the dyno. It sucks to have to pay big money for the dyno tune to find out the mail order was near perfect. But that's just the way it goes, better safe then sorry.
As far as the comments about finding a new tuner, you have to admit, the OP didn't do a very good job on explaining all the info. I don't remember any mention of you recommending a fuel pump by the OP as most of us suggested.
Good luck with the car and hopefully there won't be to many issues that pop up while tuning.

 

i agree on the mail order tunes,and you are correct i think some things got lost in translation by the op.Good guys though when they came into the shop.Anyway look forward to seeing the car when he gets it ready.

 

very handy little chart rc put together
little injector spread sheet deal.
Fuel Injector Worksheet

--------------------------------------------------------------------------------


B.H.P.





* See note below.



Warning: Duty cycle should not exceed 80% (0.80) for these calculations.



PSIG


--------------------------------------------------------------------------------

Lbs/Hr CC/Min




* Brake specific should be .45 to .50 for naturally aspirated engines,
.55 TO .60 for supercharged engines,
and .60 to .65 for turbocharged engines.

http://www.rceng.com/technical.aspx#...cted_Injectors

 

So you type in 350 crank hp
8 cylinders
fuel pressure
duty cycle
and it will tell you the injector you need.

SO we all figure this car should make 320 ish whp.
that means 20% or so drive train loss will be 385 to 400 crank hp roughly.

That means to have a 80% or better duty cycle he needs a 30lbs injector.

That is a very helpful site.

Most injectors will max out at 80% duty cycle and this is the accepted industry standard.
this is from the website i linked.

 

Any numbers yet?

 

LOL!^^^^So what did the car do?

 

he hasnt brought it in yet.

Im doing a 383 lt1 tomorrow...Its a 94 camaro i do believe.

 

It also depends on the fuel pressure used as a brake specific when determining the injectors rating. You being a ford guy should know this firsthand, as there is almost always a window. Most ratings are based off of a 43lb fuel pressure static. Fords injectors are rated at 38psi, so alot of people can get away with an 80% or near duty cycle while using 'too small of an injector'.

That said, I do not know how GM rates their injectors, and yes, it is good to have room to grow, but increasing the fuel pressure to a reasonable rate is not terribly uncommon. Also, good quality injectors will also not lose their spray pattern when used at such levels. Hell iirc RC's used to claim you could run like 70-90psi through them without a hitch. I suppose I could go reference that from the link you just posted to their site, but I'm not going to. There is no doubt some wiggle room.

 

I just got my injectors last night and now I am curious about my fuel pressure, I haven't had a lot of time to check it out nor do I have any real way to check pressure at high rpm without it being on the dyno so I think that is something that me and elky will have to address on the dyno unfortunately. I am glad that he posted in this thread so I wasn't the only one trying to defend his good name. I also was not trying to bash Ions tune but the car is not running the way it should, I paid him his money and I got what I paid for so...I should be getting the cats sometime this week and hopefully back up to Fresno either end of this week beginning of next.