ACE1252

Right off hand, it sounds like the car was not tuned correctly. To set the FPR so low, sounds like they were trying to compensate for not doing something right in the tune. Makes me wonder if the fuel injectors were characterized correctly in the tune.

Someone with LT1 Edit experience will have to chime in on this.....

Can he save his tune as a .bin file? I know that JET DST(my PCM software) can open .bin files, but I'm not sure on .lt1 files(my understanding of the LT1 Edit file extension). I have read that C.A.T.S can open .lt1, but I'm not sure if that was carried over to JET DST...I don't think so...but could be wrong.

If he can get me the .bin file, I'll look at the tune.

I'm no tuning professional, but I do know enough to see if the shop was on crack when they tuned it.

mrmint69

Lets say you run 10.99 quarter mile. I would bet your injectors are two small for your setup. I have 42's and run high 12's and they are the showing right about where I want them to be, without ever maxing them out. I would like to see your datalog and take a look at whats going on. Just a suggestion, but I would buy some new injectors and go at least 60lb. Retune the engine with all your current mods. What is your experience as far as tuning and understanding the whole process? You seem to have some knowledge, that helps to help you.

numskull

thanks. When I get home from work tonight I will look into that. I think I can change it to a bin and ive read that you can convert them to bin. Im gonna do the bench test tonight on my O2's also.

numskull

I did a bench test on my O2's, and one barely even moved on my voltage meter, the other one did only produce .4 of a volt. Do yall think this is my issue?

ACE1252

How did you test the O2 sensor? How hot did you get them? Did you do something like this video?

[autostream]http://autostream.com/camaroz28/?page_type=firebirdplayerthumbnail&framepage=2615& transactionid=1334734346-75191131167&posted_by=ACE1252_www.camaroz28.com&yo utube_video_id=stFhLSHsOGg[/autostream]

Injuneer stated that the O2's were active, but if you think they are bad, get some new ones for piece of mind. Buy AC Delco brand if possible.

I personally don't think that is going to solve your problem. You seem to indicate that the car was tuned with 30psi of fuel pressure, that in and of itself points to terrible tuning(or something wrong with the engine while tuning), if that was the case.

Your website info states a lift of .525/.540, brand Lunati. Just doing a quick search, do you know if this the cam?

Lunati 54762 - Lunati Hydraulic Roller Tappet Camshafts - Overview - SummitRacing.com

Has the car been run on NO2 on a regular basis? Also, have you done a read on the plugs?

Injuneer made mention of 80kPA MAP at idle. That is a very high reading for idle. That reading is closer to WOT(around 98kPA) than idle. However, I'm not sure what a cam like the above would do at idle. My CC503 is 45kPA at idle.

numskull

After going back and looking, I don't know if I heated the O2 to 600*. i didnt wanna over heat them, but this is the video I watch. My datamaster log does show that they are reading.

As far as the NOS, it hasnt been sprayed to death. The orginal owner said he sprayed it a few times, but got rid of it to the guy I know, and he had it for about 3 months and got on his death bed, he didnt use it either. My uncle took over everything and drove it around alittle and saw the oil pressure drop at a stop sign and shut it off and had it towed, and that when I bought it, he never sprayed it, he said the car scared him. Ive never sprayed it.

I do believe that the cam, that all I can find with that lift, the man past before I could get all the spec sheets.

The plugs are black, the O2 sensors where black.

Im wondering if my FP gauge is maybe bad...I need to double check that. Running its at 30-35 lbs and when I shut it off it drops down to nothing.

I converted my LT1 file to a BIN last night if you would like to look at it. I ASSUME this is my back up tune, I havent figured out how to pull the current tune off yet pcm.

Im going to look at my injectors again, to make sure they are #36. is there serial #'s on them.

Did you watch the video on my web site? one of the I actually crank it and ya can hear my other problem during cranking, dragging and I just had the starter rebuild cause I was thinking that wast the problem, lol. that a minor one i hope.

Also ACE, here is the location of my BIN file, if you wanna check it out. Thanks

http://www.4shared.com/file/lKI4VbLh/backup.html

ACE1252

Sorry to hear about the passing of one of the car owners. Prayers to his family.

I'll look at the tune when I get home tonight.

The pressure falling off so quickly sounds like there is no check valve system in place with the dual pump setup. That or there is some kind of air leak between the regulator and fuel pumps. I'm not sure how they would be setup in the tank. Someone with a dual setup might can speak to how they are installed(with or without check valve). I also just read that it could be how the regulator operates....so it might be normal....not sure.

numskull

Thanks! If you see something that I should try let know and I'll load it in.
how much timing should be in at cranking in closed loop? Im just thinking on my old Hei motors id play with the timing to get the best cranking when it was hot.

mrmint69

I had a bad pressure tester and it would never go over thirty. Definately check with another one. Hard to belive the car could run on that pressure anyways.

ACE1252

My version of Jet DST would not open the file(must be because this software is OBDII instead of OBDI).

However TunerPro RT V5 did open it so I could see it.

Injectors flow rate = 36.15psi
Cylinder Volume = 780.01 ml/Cyl (which is 383)
MAF calibration is stock(compared to mine)...
Cooling Fan1 on Threshold = 87*C(around 180*F)
Cooling Fan2 on Threshold = 89*C
RPM Cutoff = 6200RPM
Target Idle in park down to 56*C = 600RPM, 44*C = 800RPM, 32*C on down = 1000RPM

The injector offsets and short pulse adders have been massaged(increased). I'm not sure if they are reasonable.....I have not run across an injector calibration sheet for accel injectors.

I'm also not sure at what pressure Accel benchmarks the injectors. If it's 43.5psi, then the flow rate would seem to be fine, but if it's different like the way Ford's rail pressure is then it is wrong.....

I still need to look at the VE tables and such, but at this point, I wouldn't call this tune completely out in left field. At this point, I think you are looking at some type of electrical and/or mechanical issue with the engine.

ACE1252

Found this bit if info on Jeg's site. Looks like the rail pressure they test at is 43.5psi.

JEGS

Can you get a model or serial number off one of the injectors? The "36#" injectors on the Jeg's site are actually rated at 37.1#@43.5psi.

http://www.jegs.com/p/Accel/Accel-Pe...49691/10002/-1

Look under the "High Impedance 36LB Injectors".....that could be one small issue if the model numbers match up(injector flow rate should be 37.1 instead of 36.15). However, I don't think it would be enough to flood the engine as you describe when you turn up the pressure to 43.5psi....

ACE1252

The one titled "Another tune rev to 7000"?

I just watched it and, to me, it sounds like the starter simply has trouble turning it over on the compression stroke. Do you know the compression ratio of the engine? I'm not sure at what point the stock starter would have issues turning over a high compression engine. You may simply need a new starter(or battery even)....what is the voltage of the system with the engine idling?

I think Injuneer mentioned in one thread that he is using the stock starter on his machine with no problems. However I might be wrong. Best to let him verify that.

Edit: No I'm wrong, he is using this...."CVR Protorque Starter" according to his Mods list.

ACE1252

VE Tables, for the 383 file, from 2800 RPM and up are stock LT1. From 400 to 2600 RPM, they are not as low as my CC503 tune.....not sure what they would be on a good 383 tune.....I'm guessing it depends more on the flow of the heads/cam combo rather than the engine size since the engine volume increase is already accounted for in the constants.

I've pulled a couple of 383 files off Monodax to compare, but have not done so yet. Also, not sure if what I got off Monodax is any "good".

Spark tables for this file are generally less than stock LT1 spark tables.

My CC503 "generally" has 3* to 6* more advance than the 383 file up to the 4000RPM region. From that point up, the differences are only 1*-1.5* degrees.

numskull

The starter is a Powermaster 9600. Ive had it rebuilt cause of that. Only does it when Its warmed up.

The compression I was told was 11.5 to 1

My injectors are black and yellow, where would the #'s be?

Maybe I should try to pull the tune off the car to see if it was the real back-up....I havent figured out how to pull the tune off with LT1 Edit, yet.

Thanks for your help man, Im try to learn all I can, this is my first non carbed toy

numskull

Thought just come to me, Would the timing being set low cause of the NOS. I actually removed the NOS system, I had no plans of using it.