badgta

iTrader: (4)

i need to ask a question that refers to tpi and at the same time to the tunibility of it.....

i have built a 383 with afr 190's a custom comp grind cam *230in *236ex at .050 with .510in and .520 lift exhaust and ground on a 112* lsa , 30lb ford racing injectors and stealthram........

it has 10.3:1 compression......

my question is will the stock 89 tpi computer and chip be able to run this motor enough to be driven home, without possibly causing damage to it do to running severly rich or detonation??

it will have 6* intial and 33* total at 3000, or "stock timing"

will i be ok for the ride home?

Ed Maher

No, you won't be able to run that engine with a stock chip with 30# injectors. It will run way past rich, if at all it would be blowing black smoke and wash down your cylinder walls, leaving you to drive straight back to the shop and have it rehoned and reringed.

With a few grand in go fast goodies, another $200 on chip burning stuff should be chump change. the best MAF starter bin is the ARAP, although it's spark tables are extremely aggressive but thats an easy fix.

If you really have an itch to take chances and you need to drive it with a stock chip, keep the stock injectors on it. As long as you aren't doing heavy throttle they'll work fine for normal driving.

badgta

iTrader: (4)

thats what i figured........ i gave my stockers to my friend for his 5.0 to try and help him out with his quest for hp....

belive me the last thing i want to do is tear this thing back down again......... i guess i'll just have to raise some more dough and try to get a chip.........

but before i do i have one more good question.....

i can see how 30lb injectors would run the motor severly rich on stock heads, but afrs will have alot more air to go with the fuel, so couldn't the stock chip compensate for this with trying to keep the a/f ratio 14:1?

more air+ more fuel to cancel eachother out?

Guest

No.

Ed Maher

The stock chip will never compensate for injectors that are that much larger. An engine doesn't use more air at idle just because it has big heads. In fact hot combos usually move LESS air during low rpm situations, and don't start to really move air until you get into at least cruising speeds. Thats why radical engines compound the problem of needing big injectors to make power. Your idle injector pulse width is too short for the injector to even open, so the min fuel you can get is too much for the engine at idle with a radical combo.

The ECM couldn't compensate regardless though. The MAF measures Xairflow, and the ECM looks that up and sees it needs Y fuel to get X:Y fuel ratio. It then divides the fuel needed by the injector size (and 8) and shoots.

I think you think closed loop is especially intelligent or something. It's not. And it's not even on all the time. For example, the first few minutes after start-up, the ECM doesn't pay attention to the O2 sensor until the coolant temp comes up. And until it does, it is going right off the tables, so if your injectors are 50% bigger, you get 50% more fuel, and washed cylinders. And even if you did have immediate closed loop through some magic, the ECM can only compensate for a max of about 15% too rich. Anything past that and it will still only be pulling 15% fuel. So best case you'd still be over 20% too rich. Just not a good idea no matter what really.

Guest

LOL! Ed, you did it the hard way.

And my 2 letter response beat you

badgta

iTrader: (4)

i just had to ask to be sure..... thanks for taking the time to explain dude...... hopefully when i get the chip she'll fire right up and run smooth as hell.....

89gta383

iTrader: (5)

Put the stock injectors in it and it will drive home.

I sent you a pm.

Bort62

Doooo biiiii doooooo

badgta

iTrader: (4)

i can't take'm back now......... my friend needed some for his 5.0 rustang....... his 19's were rusting like a ford does and were just junk.... he tossed them in a river and helped me out on a few thing so i said he could have mine....... so i figured i'd be a true friend and help him out... hell mine looked like new when i gave them to him......... so far he has a gm alternator, and my tpi injectors... i have ford cobra r rims.......... weird huh?

gflo383

sorry to say, but you guys are wrong, i drove my 383TPI with 24lbers for a couple months, no probs with the stock 305 chip, now i bolted on a supercharger and added 30lbers, still drivin her, runs good, idles a little rough, and is stoich most often at WOT, a little on the rich side, but it does run. i do think however, with those 30's on a NA 383 it will be rich at top end for sure, i know this because thats what i put in my 383 when it was first done, i had to switch to 24s.... but anyways, it will be okay to drive home!

Ed Maher

We are wrong? Hmmm, exactly what part did we mess up? If you can find a hole in my explanation feel free to clarify for us. Maybe in the meantime you can tell us what your BLMs are?

Bort62

Go ahead, listen to him.

Im sure it will work just fine, LOL after all his car Ran a 12.7 On the Gtech!

Those of us who actually know how the computer works and what it is doing don't know WTF we are talking about, Im Sure.

I fired a Supercharged L98 w/ 30 lbs injectors using a BIN set for 22 lbs... in the 2 seconds we let it run just to see if the PROM adaptor was working, It stunk so bad our eyes waterd, and black smoke just poured out the exhuast.

But go ahead, listen to Mr "I don't have to follow the laws of physics" over there and see how it turns out.

GhostBuster

hahahaha. A blown 383 that ran 12.7. My cousin went 12.4 with a 305 and a vortech he bought on ebay. gflo, i think something is wrong with your car.

88 350 tpi formula

iTrader: (9)

if the prom was made for 22#inj and you had 24# wouldn't it just be really rich? why would it fry the l98?(tell me so I will learn)


he asked if he could get it home with 30#inj. so he can but, it will be maxing as far as it can.

no wrse than 24# in a 305 right? people do it! why only they can say look at all those 5.0 guys who do that too.

badgta

iTrader: (4)

i'm not taking chances....... i might fire it up to set the timing but thats it, hell i don't know if i will do that....

i'm not saying your wrong gflo, thats why i asked what i did with this thread... hell when it comes to the real technical aspects of computer programing i'm like as hell.....

hell, me and ed, and bort62, pretty much dislike eachother with a passion, but i will say this, even though he might not like me, he has given a very well thought out explination on how it wouldn't work and what might be the consiqenses if i do go with the stock chip...... and to me thats priceless......

and like he said, a good chunck of change has been put in it and it's not time to skimp now....... hell 75$ bucks and i got me a chip that will get me home under the most dire of circumstances....

true not every motor is the same, mine might be fine, and then again i might cost myself another rebuild "which i cannot afford"...

it's time to live up to a saying i have adopted, "chance favors the prepared mind" and not take chances i'm not prepared for....

i do appreciate the help though, it means alot gflo.... i just have to think about whats invested time and money wise and ask myself, is it really worth the risk?

Bort62

Ed May be an *******, But at least he is Usually Right

As far as Disliking you with a Passion... Don't Give yourself that much credit... lol

You appear to be improving however, and that is All I ask. You are exactly right... You have so much invested already ( and you have already seen how cheaping out costs you in the long run ) that it would really be false economy to try to cheap out now.

As far as the cost of the CHip, who is charging you 75$ ? Ill Do it for 40

Bort62

Its bad because Raw gasoline in the cylinder will wash down the cylinder walls, stripping them of oil ( ever used Gasoline to clean parts? It works GOOD )

So then you have metal on metal unlubricated contact... How long do you think your rings will last ?

Additionally, the fuel will then end up in the oil, and dilute the oil. Gasoline isnt a very good lubricant, and getting enough in the Motor will do the same thing to your bearings eventually.

24# On a 305 Will Have a Similar Effect. I don't think you will find anyone who is running 24# injectors on their stock 305 BIN on a 305, for very long.

badgta

iTrader: (4)

the guy who's burning it has a good following of people that have no complaints to date and that were very pleased with what he burn't them......

i myself have talked to him on several occasions and he seems to be and alright and sincere guy.....

don't get me wrong, i'm not saying your bad or anything but i'd like to give him a try and see what happens......

i plan on getting into prom burning after the first of the year, so i can fine tune mine.... or any icon guys who need it...

i think it would be impossible to start to try to get a chip perfect unless you have the car right when ya do it.... but for what i need i think he could pretty easy to get into the ballpark and set it so it will be fine until i can get it broke in and such.....

i'm not saying prom burning is easy, but i think i could do it....

and hell you can download tunercat for free so all ya need is a burner and your set...."or am i wrong?" they tell you that the tunercat is a trial version but all you have to do is set the date on your computer to a day before the limit and it will last forever!!!

ahhh, lord. maybe one day i'll get my pos running and kicking rustangs *** once again?

88 350 tpi formula

iTrader: (9)

oh, thats what I thought I read your post wrong I thought the supercharged car was damaged. but, I do know that the fuel get in there and so on.

you are right on the 305 and 24# inj most of them are sold and never seen again or the dumb kids hit trees. I have never seen one go south though (yet)
I know 5.0 guys who do run 24#inj with stock chip and mass air flow. I also know some one with a built 5.0 supercharged but has 30#inj and no ecm work only a msd retard box...... he bought it that way and knows it is all wrong and plans to get 24# inj and have it tuned by a some what local shop. he has had the plugs foul out already. it is wierd when you drive it though it feels like your are running out of gas! you give it throttle nothing little more and nothing then all of a sudden it just goes you let up a little and it still is going strong then it like stalls but, not really just drops all power it is the weirdest thing. like I said when you just drive it it feels like your running out of fuel( if you ever drove a car that low on fuel you know what I mean)

Bort62

Pls don't advocate stealing or pirating software on this site Badgta.

Tunercat is a great program that has Facilitated alot for us, the 60$ is a minor pittance for their development and continued support.

If you think that is too much... write your Own.

SATURN5

My only question is when do you plan to switch to a 730. Going by your data, running a 165 MAF is going to max out the MAF. I'd look into swapping over to a 730 SD style in the near future. Now I know some of the MAF guys will probibly disagree with me and there is nothing wrong with the 165, other than the limitations of the software and MAF. Swapping over to a 730 is not that hard, or expensive and can be done in a weekend if you plan it out right. Bort62 will verify that. In the end I feel you will be happier with a 730.

Oh... Bort62, going nutz again...lol Have a second M90 on its way.
cheers, Bob

Bort62

Weeeeeeeee!

badgta

iTrader: (4)

pirating???? whats that?? it's like hacking, i can't even begin to fatham how to do it, or why anyone would wan't to...... i'm clueless.....

when i say turn the date back, your not stealing it but just using what they gave you....

kinda like the debate on satelite tv, your not really stealing if the signal is on your property, your just pulling in whats there..

but i can see how posting that is wrong and for that i'm sorry and apologise.......

gflo383

Bort, your kind of a DICK, i was just saying he would prolly be ok to drive it home, tryin to help out a fellow 3rd gener, im know my car would be much more efficient, and faster..... but i was just saying, i have drove my car for about a year and a half, never had gas in the oil, never fouled any plugs.... it does run rough at idle, and i wish i knew more about prom tunning. by the way, i ran 12.7 AT THE TRACK, with 3.23 gears and a torn fpr diaphram, i then installed 3.73's a new fpr and ran 11.7 on a gtech. not bragging cause its nothing to bragg about, just sayin its not that bad for being a stock 305 prom, give me some credit for that didnt mean to **** any one off, thats not what im here for. sorry again.... just cool off a little.

gflo383

ed, i guess i shouldnt have said it the way i did, i just meant he could make it home from the shop wit hno problems, but thats just from my experience, im sure after he drove it, it would eventually destroy something.... and bort62, i dont know what was wrong with your friends l98, my car doesnt do that" smoke so bad your eyes water" although i could for sure use some prom tunning. i think people take thing s toooo personal on here, you must realize, i dont know any of you, and you dont know me... some things written and then read are takin differently then if i said them,... ya know what im sayin??

89gta383

iTrader: (5)

Just put the 30's in and turn down the fuel pressure, it will be fine.

badgta

iTrader: (4)

time out!!!! lets everyone step back and count backwards from ten....

i know what ya saying about how people can take things the wrong way.... thats why i said tanks to gflo at the bottom because it sounded like i was taking sides or somthing......

belive me thats not what i intended at all...... i have learn alot from this thread.... how some have nearly the same combo and have been fine for the drive home and how some have had problems that tuning had to resolve before the drive.........

but it still comes down to the question of chance..... am i willing to risk a good chunck of money to start it and drive it home or should i just tow it home and wait until i get a prom?

i'm sure that from a direct start 14 miles to the house might not hurt ,but it has to be timed and the cam broke in as well, and that unfortunantly takes time........

i guess i will have to just try to start it, and get it at least timed, and if it ****s up, then i will personally do a write up on how bort and ed said not to and how i was stupid for even trying....

or if it's ok, then i will do a write up of how not always will someones luck be the same as others like you guys have described above......

personally i think it's going to play out like this.....

the stock programing is thinking 22lb injectors and stock heads...
it will fire the 30's thinking theyr'e 22's that means more fuel.... but it still thinks stock heads, but i will have the afr's... which is a hole lot more airflow..... so it's going to be a little hard for the computer to thinks it's ok but i think it might do well....

kinda evening itself out a little.... and with stock timing curves and 93 octane, it shouldn't detonate.....

but hell 9 out of 10 times i'm wrong so only time will tell......

and as far as you guys thinking someone hates you, i know i sure don't... as far as i could tell your just trying to help by sharing your experiences with us..... hell who could get mad at that?

Guest

Actually, it will happen more like this:

When the car is cold, it doesnt make adjustments. It runs right off the airflow (maf or map calculation) and determines a fuel flow rate based on this. This is based on the 22#/hr injectors. The ecm has NO idea you put 30's in there. That means it takes the airflow it reads (and this will be accurate no matter what you do, at least close enough that the difference isnt significant), does a calculation, and shoots the fuel in. The actual fuel delivered will be 30/22 or 1.36 times as much as it thought, because its stupid and doesnt know what you did. 36% more is enough to cause all sorts of problems.

Once the car warms up and it starts using the 02 sensor, it will know something is amiss, and it will try to compensate for this. The BLM's will hit the end of the adjustment range, and the car will still be rich. It cant make a correction for a 36% increase in fueling.

I wouldnt do it if I were you.

gflo383

i guess if its not too big a deal to tow it home, why not, be on the safe side right? i just dont undersatand how my car runs fine with no prom tunning at all, and others wit hslight mods runs like crap???? oh well. maybe ive just been lucky so far

badgta

iTrader: (4)

so all a person would have to do is change the injector constant to 30? in all the $6e bins?

88 350 tpi formula

iTrader: (9)

well? I want to know too! I changed mine for the 24# inj I have but, what about he 30#inj. will the ecm be able to run them at that low of a duty cycle?

Bort62

Setting the $6E to 30 lbs/hr would Be a good start, and at least put you in the "tolerable" Range. But getting respectable BLM's is likely going to require alot more work than that.

Gflo, your definition of "fine" means little. I know lots of guys with hopped up cars that run "fine" yet run 2-3 seconds slower than their Mods would indicate... take a look at the whole TBI Crowd. Not to insult, but 12.7 out of a Blown 383 Is not "fine" In my Book.

In your particular circumstance, the Increased airflow from the blower is most likely similar in magnitude to the increased Fuel from the oversized injectors once the MAF has Maxed. So your probrably at least closer to right than a NA motor would be.

Im a Dick Because I saw you give this Kid Bad advice, advice wich could potentially cost him a lot of money.

So Yeah, I jumped on you for it because I didn't want him to make a mistake that would be very devistating, because he followed your incorrect reccomendation. Sure I may appear a Dick from one standpoint, but thats o-k.


Badgta's musings about increased airflow compensating for increase fuel show he is at least thinking about the subject, the problem is he doesnt know the details.

Madmax put it dead nuts... The MAF will accurately measure any increased airflow ( below its 255gps limit ) Your engine produces, so your fueling is still going to be 36% Innacurate untill the point where the MAF Maxes.. beyond that it is anyones guess what happens wich is a whole nother subject entirely

In all honesty You could probrably fire it up, break in the cam, and Drive it your 14 miles, You may not notice the effects for thousands of miles to come, or it May start knocking 12 miles into your trip. Would I do it ? Hell no.

You can get away with all sorts of rediculous things with cars... people abuse them everyday. The thing is when you build a Motor to your own exacting specifications, you don't want to take any chances or introduce any variables. One of the biggest Benifits of having a freshly rebuilt engine, is you know its solid, you know its been treated right and isnt going to suddenly fail on you.

So why would you start abusing it and take away that certainty ?

Do it right, or Do it again folks... Things never change.

gflo383

wellput! i guess i never thought of it as my car being so far off its potential, yeah, sure i thought i would gain a few horse, and a lil more driveability, maybe a tenth or two in the 1/4, but 2 seconds?? damn, i guess i am in need of some tunning... interested in helpin? $$$$ im just getting into the DIY prom tunning, and i plan on buying all the required hardware/software etc. but i dont think ill be able to tune my car when all said and done. till the day i can do it all myself, ill stick with bassic repair to general publics automobiles