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I don't remember much, it was a few years ago when I watched it.  If you are starting with no knowledge, it's probably a good buy.

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update:

 

New injector info in.  Locked timing at 25 for messing with idle mixture and all.  went back to the clean 350 hot cam fuel map.  dumped some fuel in it.  bucked and coughed worse.  gave it some more.....and more....

 

Now it cruises pretty well.  some a little surging but no bucking or popping.  I think deaccel is TOO lean (shuts off pretty much and will die if you push in clutch without a little gas)  only have had it up to 3000 or so.....even rich and poorly tuned it is snappy.....very snappy.

 

Logged a couple minutes this evening to review and adjusted a couple spots even more.  I have Fridays off so I think there will be alot of logging and tuning come Friday.....I feel now I can at least limp down to the gas station to fill it up with some 92.

 

I feel like somehow the AWESOME ability of Mike and Disney has managed to get me here without them actually looking at my junk.

 

Hoping to post some videos this weekend.

Ashley P likes this

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picked up a misfire I need to track down and still dealing with a belt alignment issue (it is much closer now but still off a hair)

 

I love how small block chevy's are so easy to build.

Cody and 66sprint6 like this

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fresh cap and plugs and seems to be revving ok now.

 

My shitty cramped enginebay requires pulling the drivers side accessory bracket loose to get the valve cover off....had it shimmed with a single washer behind each bolt.  Guess I dropped one out and need to get it back in there so called it a night. 

 

This weekend I am going to pull the crank trigger off and check my pulley alignment with no spacers (should be ok then)  Then measure the trigger wheel thickness and see about finding some AL stock that thick I can then drill and weld to the back of the brackets.....total pain but knew I had to do this months ago when I shimmed with a washer....getting it sorted and correct.

 

Oh did I mention I have to pull the fans and maybe radiator out to get enough room to work in there?

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I am ready to burn this pos....

 

So I found my main power feeds off the factory distibution block were loose.  I am guessing I spun the nuts down by hand while pulling wires and never went back to get them tight.  Snugged up I am showing proper voltage now in software....that problem is solved  This also cleaned up my datalog A/F signal a bit....I think.

 

So everything seems fine until the motor hits 170-175F.  will free great below that.  once it hits it it will no longer build RPM no mater how fast you open the throttle and even struggles to idle.  Timing locked at 25degrees and in open loop.  170F is where I come off my cold enrichment but at 153F it is only at <10% enrichment so I can't see that I am going THAT lean loosing a couple percent of fuel at idle/low rpm.

 

the A/F at idle is showing pegged lean but it still burns your eyes with it running in a slightly closed up garage.  I am debating  anew wideband on it now but damn are they pricey.

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I can loop the block and it is fine.  stop and idle for 2 mins and when I go to pull out it bucks and coughs like crazy.

 

Time for a carb and HEI I think.

JohnC likes this

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If this was using factory logic I'd say your O2 is erroneous because it runs good in open loop (when O2s are ignored), but bad in closed loop (when O2s are used).

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right now I am in open loop and it runs like crap whenever it gets warm it seems.  I dumped a ton of fuel on it (doubled up what was in the tune as of earlier today....which it was running fine on before)

 

it just flat wont take any throttle input once it gets warm period.....I had to idle up the street to get it home....but 60 seconds earlier it was WOT pulls out of the driveway and didn't even touch the tune any....WTF!

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You state " right now I am in open loop and it runs like crap whenever it gets warm it seems".

When it runs bad is it in open loop?   How do fuel trims compare (running good vs bad)?

 

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Posted (edited)

4 hours ago, Ashley P said:

You state " right now I am in open loop and it runs like crap whenever it gets warm it seems".

When it runs bad is it in open loop?   How do fuel trims compare (running good vs bad)?

 

it is always in open loop right now as I have closed loop disabled.  no trims as I am in open loop so fuel delivering should be the same.

 

I took some logs and whenever it acts up it goes off the charts lean on the data log with any throttle input as if it is not delivering additional fuel (think clogged main jets AND no accel pump on a carb)  my AE vs CTS is flat in this area.  it seems if I shut it off and let it sit for a minute or two everything is then fine for a few minutes until it starts doing it again.  All I can think of is the ignition actually dropping out but not sure how to check that with the crank trigger (my "tach" signal is off the crank trigger and not the coil/distributor)  I have a cheapo suntachIII laying around I think I could hook up to the coil in the truck and see if my coil itself is dropping out but may not tell me much if I am dropping spark in the chamber.

 

a 750 cfm carb is seeming so tempting to toss on right now.  When this is not acting up it seems very strong and healthy (just way far out on tune still)

Edited by NukeWorker
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Look at the ae decay.  It ae vs. Time.  They are probably set to add more fuel after startup and slowly drop to zero.  Maybe try raising it off zero.

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3 minutes ago, Mike said:

Look at the ae decay.  It ae vs. Time.  They are probably set to add more fuel after startup and slowly drop to zero.  Maybe try raising it off zero.

decay?  I don't have a AE vs Time table

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I don't have the software on my pc anymore.  I'll have to look up the name.

 

Maybe it's startup fuel decay.  An adder for fuel right after startup.

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6 minutes ago, Mike said:

I don't have the software on my pc anymore.  I'll have to look up the name.

 

Maybe it's startup fuel decay.  An adder for fuel right after startup.

runs fine within the startup decay window...issues seems to be more after running for a period...I think.

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Have you checked your fuel pressure when it gets warm and starts doing it?

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so I have had a noisy pressure regulator (Aeromotive)

 

I removed my gauge for a sending unit for the XFI (only to find the ground return missing from my used harness)  I am going to try and swap the mech gauge back in on a length of braided line so I can get it up on the cowl.  All I can come up with is that it is either full bypassing all the fuel it can or the pump is dropping out (it is a new pump)

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So I swapped on my mech gauge.  pressure was holding "steady" at just under 40 psi static (my idle tune is **** so there is some vac fluctuation in it....line removed it was steady)  I might dial it back a bit closer to 35psi.  Truck didn't seem to act up at all last night though.  I'll poke it along a little and see if I can narrow it down to something

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Relocated the fuel pressure gauge to the cowl and seems to be holding pressure ok.  still runs like crap once it warms up.  I am starting to lean towards a head gasket or cracked head issue.  These bowtie heads were known for cracking if they got too warm.  one was cracked and I had to replace it already (when I had both rebuilt)  I hope the other one is not the older crack prone casting still.  

Well I am pulling headers off tomorrow and doing a compression test on the motor to make sure nothing internal is wrong like a holed piston or something.  Something seems off mechanically to me.  If it looks internal it might be getting parted out.  If not I might be tossing a new harness at it and see what thats gets me as I seem to have issues with the current one.

JohnC likes this

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Compression test was good.  Pressure tested coolant system.  Pumped it up to 20psi and an hour later it had dropped to 18psi.  So seems to pretty much be holding ok.

 

I think my issue is a combo of the crank trigger/coil/distributor and the hanky used main harness.  Since the headers had to be pulled to compression check and new parts are not in the budget right now I think it is time to toss it in and part this project out.

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8 minutes ago, Ashley P said:

Huh?  Part it out 'cause it runs bad when warm?  

I have too many projects and not enough space.  The truck itself is clapped out.  I started building this motor in 2013ish.  in that time things have changed and I need the space and would rather have this motor in a classic muscle car.  I just wanted to get it dialed in and tuned so it would be ready for a transplant.  It runs poor before it is warm (like at 120F and gets worse/doesn't run at 170F)  I am sure it would run strong on a carb and distributor but changing everything over is out of my budget right now (time and money wise)  I would rather have my Fairlane out here to work on and I need to make room for it first.  I am keeping the motor and XFI and maybe the T56 but the rest will get sold off.

66sprint6 and Ashley P like this

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