i installed a engine this week and it idles at 1500 usually. and it flutuates sometimes. in the mornign when it is cold it starts right up, but when ever i try to restart it, it cranks for a long time before starting. even when i get to school and leave it for 4 hours. im thinking it could be my base timing is too retarded, plus my chip needs a lot of tuning. specs on engine are

357
holley tbi
weiand stelth single plane intake
dart iron eagle heads 2.02/1.60
crane powermax cam
222 intake/234 exhaust
467 in. intake/.494 in. exhaust
114 degrees lobe sep
hooker headers and catback
5 speed
1.6 roller tip rockers
65lb injectors

i can send anyone my bin, and winaldl info to see where i need to change some stuff, or you can change it for me if ud like.

 

can you post some winALDL data? BLM's?

 

what is your fuel pressure? did you consider the fuel pump?

 

i have a walbro 255lph and its set at like 20-22 psi.

also i have a check engine light - "Rich 02"
and now a high map code.

ill post the winaldl data and my bin tonight.

 

heres my blm, knock, and bin files.

as soon as i came off the freeway in two cells my knock just jumped over 100. so im thinking thats a error. u can see it in my knock file. those two values were blank till i exited the freeway and was coming to a stop.

http://home.comcast.net/~tkd89rs/BLM.txt
http://home.comcast.net/~tkd89rs/KNOCK.txt
http://home.comcast.net/~tkd89rs/2.bin

 

it is pretty rich all over. verify the BPW in your prom as accurate. reducing fuel pressure may help. how did you arrive at 20 lbs as a starting point? day one of my mods i was at 11-12 lbs with 65 lb injectors. i ran very lean in easy driving. WOT i guessed i was running very lean so added a vafpr for a month. that is a pretty strong cam and may require some tuning in idle area of VE. what is the idle set at in prom? i assume the idle stop screw does nothing for you. The IAC counts may need to be looked at as well. IAC may be bleeding air in causing high idle. possible vac leak? cant read the 3rd file since my Company blocked it. maybe someone that has a better level of knowledge will jump in here. i am adding a similar cam and 454 TB in April so i have an interest in your situation.

 

well jon has told me to back off my BPW till the blms get into the 120's. so thats what im doin first. it was at 135 originally. i put it to 128 yesterday. tomororw mornign im gonna try 120.

 

If you know the pph rating of the holley injectors your using then use that to construct the bpw constant. Since your running them near the pressure that their rated at youll get an accurate bpw constant. From there, start making adjustments to the VE table.

 

heres my new files. im at 10 degress initial advance.

when hold the throttle about have way in gear it climbs to 5000 but then stops there. it wont go past 5k like its hitting a rev limiter, it starts jerking and not becoming smooth. but if i floor it, it will easly go to 6 grand. is this a lack of fuel up there or timing maybe? once i floor it im in PE right.

and it still cranks long when hot.

http://home.comcast.net/~tkd89rs/1BLM.txt
http://home.comcast.net/~tkd89rs/1LOG.txt
http://home.comcast.net/~tkd89rs/1KNOCK.txt
http://home.comcast.net/~tkd89rs/4.bin

 

Its probably a problem with or too little (or possibly too much) timing up there taht causes the motor to nose over. The timing tables also stop at 3600 rpm and your jsut on the slope SA.

Incedentally, doing the math for the injectors gives a BPWC of 127. Looks like your pretty close to that already. Time to start looking at the VE tables. The stock VEs are typically pretty far off from what your motor would want. I had the same problems, 108 BLMS everywhere. Start ironing it out at idle and then work your way out from there. Once you have teh VEs sort of quasi-dialed in then you can start looking at the timing.

 

Double post...

 

those readings was with teh bpw set at 120

 

the calc for BPW takes into account FP.

 

Hes running them at 20-22 psi. IIRC, the holleys are rated at 22 so he should be getting the advertised pph rating out of them.

 

it stilll doesn't pull past 5000 like im hitting a barrier, unless i floor it. im gonna try and lower the psi and see what that does

 

I woulndt tinker with the fuel pressure. Leave it where it is. You need to start tuning the fuel trim, and then the timing. Leave the fuel pressure there and set teh proper BPWC. If you find its ok out top but it starts going async then you can get a VacAFPR. Youll probably want that extra pressure out top with your motor to help the 65's keep up.

 

From the stock 02's it looks like its rich up top, or about where its supposed to be with the commanded stock AFRs at WOT. Probably not a fuel problem. Cant tell for sure w/o a WB-02 but start getting the fuel roughed in before you worry about that. Its probably a timing issue anyway. Cant fix it all at once, need to do things in steps. Another thing that can help is lowering the %tps threshold for power enrich so its not still trying to shoot for 14.7:1 when the map is around 80-90kpa.

 

so i should put my BPW to 127 and then lean out my fuel table.

 

Thats what I would do. Probably best to use the rated flow rate of the injectors to construct the BPW and trim the fuel instead.

 

Oh, the generic formula I have written down is

BPW = 1461.5*[(Engine vol. in liters/8)/(Injector flow rate in gms/sec)]]

That should give something close to what I said. Use what the equation gives you and dont forget to include those extra cubes from the rebuild.

 

I can only suggest that you run a smoother mapped main SA table. The stock table is complete junk for any motor with headers and a free flowing exhaust.
Dim, where did you hear that the Holley injectors were rated at 22psi? If that were the case, then all of the 'replacement' 670cfm TBI's were lean from Holley. 65pph rated at 22psi is equal to 48pph @ 12psi. I know my unit was one of the very first to get the new injectors so maybe the regulator was old... but I doubt Holley would screw up like that. They would be asking for a lawsuit!
I think it's time I settle this Holley injector rated at blah blah once and for all. Time to dust off the injector test bench....
I had been meaning to do this for quite some time, now I have a reason.
TKD, look at the main SA table, it's absolute garbage in stock for, that's what I was trying to convey to you through AIM. You're probably hitting pre-ignition resulting in the 5k "rev limit." When you open the throttle hard and fast, 2 things happen. The ecm goes into PE mode and your MAP goes to near atmosphere. The PE mode might be set so rich (from the looks of your BLMs this is obvious) that you're covering up detonation from the knock sensor and doing engine damage. The other and hopefully real reason for this hard limiter is from the fact that slightly lower MAP (less throttle) results in more timing. This is normal operation to need more timing with less manifold pressure but it can bring your engine into detnation if something is amiss in the tune (bias values or other various tables). Also look at the PE spark adder, it's a good idea to eliminate this.
Start with having very mild compensation tables and you will get closer to your tune. Stock calibration tables weren't just used for one purpose. "Conditions" with stock engines have funky compensation tables.

 

Ill take a look into it but I distinctly remember hearing that the delphi units are rated at 22 psi, either that or a lot of people have been wrong over the years. I have what I believe to be 65 pph's in mine and theyre running at around 80 some odd percent duty cycle at WOT. Bit surprising on a weak *** 350 but who knows. I tried to get in touch with Delphi about getting some more info in their injectors taht they sell but they never got back to me. If you could flowtest a set that would be great! Would really tell exacly how theyre rated. Some say they are underrated, though. I personally couldnt care less how theyre rated since theyre some of the best damn injectors available and as long as they work well im a happy camper.

 

A quick search shows at least one post that states theyre rated at '21 psi'. Said 22, must be my even number preference taking over again. Either way, thats no garantee that its correct but its the best info available and thats really allt that you have to have to act on unless you ahve them flow tested. I find it believable that holley would jsut pass them off as is. After all, they jsut purchase them from Delphi and spit the specs back out on the data sheet for the tbis they sell. Would be nice to have an exact answer, though.

 

i see 8 tables with SA

SA corr idle high vs rpm
SA corr idle low vs rpm
Choke SA vs temp
Choke SA decay delay vs temp
IAT max knock retard SA multiplier
Base SA for transient SA vs delta map
Map multiplier for trans SA vs s/d map counts
IAT mult for trans SA vs IAT adc counts

does SA mean spark advance? which table should i be looking at and how should i change em.

for now im just gonna leave my bpw at 120 and lower my fuel table 1.

and maybe lower my PE threshold TPS as dim stated.

 

I wouldnt play with those quite yet. The main Spark Advance table is the one you want. Be sure to only make small changes at a time untill you become familiar with how it all works. Lowering the threshold for power enrich can help alot, too. The holly tbi will alow the vacuum to drop alot faster then the stock tbi so having it come in sooner will help the car not feel dead under moderate thorttle because its still targeting AFRs of 14.7:1 instead of around 12.5:1 (11:1 or so if you still have to have your cat.)

 

whats the title for the PE threshold. does it say PE threshold vs tps or something.

 

In Jons ECU, which is what I assume your using, its called 'TPS threshold vs. RPM for WOT mode'. I set mine for 35%, which corresponds to MAP readings of around ~75 kPa. You dont want it too early or youll needlessly waste gas, too late and itll effect performance. I think it will also go into PE above a certain MAP as well.

 

heres my newests files from today. i think im getting closer, what do u all think. i still have the hard starting problem. im gonna mess with the crank fuel ratio next to see if that helps.

http://home.comcast.net/~tkd89rs/KNOCK.txt

http://home.comcast.net/~tkd89rs/BLM.txt

http://home.comcast.net/~tkd89rs/9.bin

http://home.comcast.net/~tkd89rs/LOG.txt

 

getting back to the Q of the holley rated FP for their system. i would think holley expects you to install one of their fuel pumps in addition to their 670 TB unit and their ECU. then set the FP to their spec. if you are adding this to a carb application the above would make sense. not sure if holley expected us to replace existing GM TBI with their unit and use our GM ECU. if their lierature suggests a replacement item for GM applications i would expect the directions to ask FP be set up that high. As a side note it appears GM went to 26-32 lbs on their 454 TB with smaller injectors 1994-1995. maybe similar FP on the truck 350 cid.

 

Holley was advertising their 670 tbi units as having 85 lb injectors, I think the pn# was 502-6. Thats the direct replacment for the stock 350 tbi. 85# @ 22psi is pretty close to 55# (or 62# as some people say) @11 psi. Thats why the thing is able to run on a stock motor with stock prom. I think holley quit doing this over rating technique though, not sure.

 

i looked at the 670 holley for my application 2 months ago. Q was asked of swapping out the 65's (?) or so and adding their 85's on a new TB order. they said no can do. wont mix match. my F pump will only pump to 19 lbs??? TPI. i need to order the 85's at add cost they said. . so instead went to 454 TB. the holley 670 runs small injectors at high FP. as does 454GM TB for 1994-1995.

 

The rating at high pressure isnt holleys fault. The manufacturer of the newer tbi injectors, which is delphi, is the one who assignes the rating to the injector. Theyre designed to work at high pressure, probably because maybe the nozzle does a better job of breaking up the fuel into nice small droplets.

 

so does anyone have any advice on my last files.

 

Looking at the BLM file I'd say that areas of the VE tables need leaning out. What you need to do is to work the VE tables and go drive around again. Work the VE tables again, then drive around again.

Rinse and repeat.

By improving the VE tables the engine will run smoother and better. Then items such as DE & AE can be improved upon.

RBob.

 

what is DE and AE. and i blew my head gasket yesterday racing a LT1. beat em but now i gotta pull a head.

 

Accelleration enrichment
Decelleration enleanment

 

i think my DE is disabled in my prom. does DE mean that it completely shuts off fuel or leans it to about 20/1 ? i had a problem with engine dying after a DE to a stop sign from 50-60 mph. manual trans.

 

I think it depends on the computer your running, there also usually is DFCO, or decel fuel cut off. I believe DE does efact raise the AFR. I don't use ethier, I had the same stalling problem as you.

 

maybe that is reason my gas mileage is in toilet. i just found out i may be super rich on cold engine startup(not choke enrichment) based on coolant temps. was told my AE is mucho greater till up to temp on coolant(180). goes closed loop however at about 159 deg. does closed loop override that cold collant temp enrich?

 

I Had that same problem coming to a stop. should i just lower those figures.

 

mine was disabled by another member. i dontt know how to do it. tunercat does not offer it TBOMK.