Rate this topic:

76 posts in this topic

So I have had this POS S10 for about 10 years (bought it for a daily once I got out of college)

 

DSCF0056.jpg

Had your basic 3/4 drop on it (HUGE blocks in rear, coils up front) and some geh "stealth front grill" (IE a big hunk of perforated sheet over the headlights and all)

So I had some Bullitts laying around....

DSCF0128.jpg

 

And put on some stuff to stop better...

DSCF0157.jpg

DSCF0156.jpg

 

And then scored some other wheels (had them coated with my brake parts)

DSCF0131.jpg

 

DSCF0140.jpg

 Then the old 5 speed was getting noisy

DSCF0154.jpg

059.jpg

And wanted more looks

IMG_0366.jpg

 

Then more go....

IMG_0032.jpg

IMG_0037.jpg

Then more go no longer went....So we needed more go....

 

Share this post


Link to post
Share on other sites

Had a little help from the better half

 

IMG_20140215_112106_306_zpsef15bdd2.jpg

 

IMG_20140216_171349_447_zpsbac7b718.jpg

IMG_20140421_124007_921_zpsf78bpd5a.jpg

 

Needed more room

IMG_20140423_181827_964_zpslw9ey9qw.jpg

IMG_20140423_181839_316_zpsiths0y6e.jpg

 

Got it in....

PART_1422665381198_.IMG_20150130_184900_

20150211_193459_zpst16r3nlv.jpg

So it runs....but the XFI needs a lot of tuning (I should get Mike or Disney to come out here)

 

Basic specs:

Comp 280XFI Grind

Bowtie 225cc Iron vortec heads

Ford 42's

GMPP 1.6 roller rockers

Craptastic shorty headers

Edelbrock Single plane EFI intake

Accel DFI throttle

Some Eagle H-Beams

Coated Hyper full float pistons

About 11:1 compression

Nitrous Express Plate kit (needs installed/wired)

 

Desktop dyno says 505.  I would be way happy with 450 out of an old SBC that is still mostly stockish (no fancy long valves, iron heads, cast crank, etc)

 

I really no longer want the truck....but want the drivetrain.  She would like a Bandit car and while this wouldn't be a BOP power plant it would bolt in very nicely.  Going to run it for the winter and get it tuned/dialed in and then part out the truck so I have room for the Fairlane.

 

Well that is the plan at least.....Plan B is drive it until the 7.5" 10 bolt rear goes out in it.

Edited by NukeWorker
JohnC, 66sprint6 and Tino like this

Share this post


Link to post
Share on other sites
13 hours ago, NukeWorker said:

  She would like a Bandit car and while this wouldn't be a BOP power plant it would bolt in very nicely.

Well, someone has taste. ;)   (I can hook you up with Poncho engine parts if/when you wanna do that with a Bandit build.)

Share this post


Link to post
Share on other sites
50 minutes ago, Ashley P said:

Well, someone has taste. ;)   (I can hook you up with Poncho engine parts if/when you wanna do that with a Bandit build.)

There is a nice TA over by Seattle that needs new floors but has a fresh 400 (still in plastic from machine shop waiting to be assembled) and slush box.  No t a bad looking car for the asking price of $2500.....one out, one in is my rule I am told I have to follow.

JohnC and 66sprint6 like this

Share this post


Link to post
Share on other sites

Poked around on the tune a little tonight and dropped the idle a little lower (took it to 700 but it wanted to stall pretty easy)  Still need a ton of tuning.....really bucks when trying to cruise at part throttle (not fun in a stick shift car)

 

Right now I am trying to figure out my accessory drive issue.  Tensioner is jumping around alot and I can see the belt jumping on the crank pulley.  lots of hot rubber smell.  I doubt an alternator could put that much load on it from a low battery.  Wondering if it is an issue with the newly installed junkyard hydroboost (pedal is very high so maybe it is loading it up?)

JohnC likes this

Share this post


Link to post
Share on other sites

So I have been chasing down some issues.....mainly this motor was not liking any timing beyond 12-15 degrees.  Traced it back to a slight clocking on the distributor (I have a crank trigger) causing a rotor phasing issue.

Alternator was dead so I had to get a new one (grabbed another 140 amp drop in to match the one in the Toyota since it was only $10 more)  Of course it used a different plug so I had to change that out too.

Then the fuel pump died.  I already had a high output on hand knowing I needed more.pump so spent the last two days swapping it out.

Working on finishing the last couple wiring items.  I have my fans in but need them hooked up to the ECU.  I also picked up some Chinese pressure transducers that people have used in place of the high dollar FAST ones so I can log fuel pressure and oil pressure (and set cutoff's for both)

 

Other than I think I flipped my hi/lo beams when I did the front end swap and ditched the cheap HID ballasts and needing a screw for the distributor cap I am almost ready for some serious driving to get this tune doing better.

 

Tonight the truck really came together....having full voltage, good fuel, proper rotor phasing made this truck run WAY better.....really itching for some drive time.

Cody, JohnC and 66sprint6 like this

Share this post


Link to post
Share on other sites

So I swapped out the bulky weatherpack style 3 bar map sensor or a late model 1 bar map (stole it from my box of vortec leftovers)  Just clipped off the pigtail, soldered, heat shrunk and fired right up.

 

But now my MAP is being spotty.  some days it works just fine and other days it reads a full 99% load / 100kpa while trying to crank it over.  Fired up, idled and rev'd two days in a row.....let it sit and day and then nothing....just floods the crap out of the motor.  I can unplug it and it reads a full vacuum.  I stole one off my 4.3 in the toyota and seems to do the same thing and works fine back on the 4.3.

 

I picked up a vacuum pump with gauge on it so I can test this a little easier than cranking.  the best I can come up with right now is somehow my 5v ref signal is shorting into the signal return (could a faulty signal ground cause this?)  I haven't dug too far into this yet as I am trying to figure out some ideas.  I just hate HATE intermittent issues like this.  We were pretty much snowed in here since December until about a month ago and have left this to the side since then since I couldn't drive it to tune. (and broke 2 ring and pinions in the Toyota, built a spice rack for the pantry door, wheeled a bit in the Toyota, and worked on my RD400 project a bunch)

 

So I am down to a short between the 5v ref signal, a faulty sensor ground that doesn't let a portion of the 5v signal to bypass, or maybe it is all related to the recycle plug I am using.

Share this post


Link to post
Share on other sites

Are you measuring the actual signal voltage or just looking at the bubble on the xfi?  

Mine would show the bubble hung at 0 or max kpa from time to time.  It would still move with rpm.  But a datalog would show moving kpa.  One of the big xfi tuners said it was common and just a display glitch.

If you actual voltage is hung and you've tried multiple sensors then I don't know.

 

Share this post


Link to post
Share on other sites
56 minutes ago, NukeWorker said:

But now my MAP is being spotty.  ............................... I just hate HATE intermittent issues like this.  

As an auto tech I feel your pain.

Is there any pattern to the failures:  ambient temp, humidity, throttle position, or phase of the moon?   Have you shaken the wiring harness while watching voltage?   Does ANY other data go bonkers at the same time?

GM uses a common 5v circuit for multiple sensors, so if it's that circuit then multiple sensors will (most likely) act silly. How is xfi wired?

Share this post


Link to post
Share on other sites
17 minutes ago, Ashley P said:

As an auto tech I feel your pain.

Is there any pattern to the failures:  ambient temp, humidity, throttle position, or phase of the moon?   Have you shaken the wiring harness while watching voltage?   Does ANY other data go bonkers at the same time?

GM uses a common 5v circuit for multiple sensors, so if it's that circuit then multiple sensors will (most likely) act silly. How is xfi wired?

The whole engine harness is now a FAST XFI harness....a used one.  I found some issues on the ignition plug I had to sort out to get the crank trigger working.  but I have driven it a bunch up until I swapped the MAP sensor out, tied in for a fuel pressure sender (have unplugged it and still acts up) and properly wired the fuel pump relay to the ECU (I had been just relying on the oil pressure switch to kick on the pump which leads to LOTS of cranking to get it to fire)

 

I swapped the newer style MAP in and I don't think I have driven it since then.  it will literally start, idle, and rev.  Shut it off and the next day nothing.

 

I am not looking at the bubble Mike but watching the gauge "dash" in the XCOM software that just reads in kpa.  I should pull up the raw voltage reading on it and see what I am getting but I am sure it is close to 5 volts.  I also grabbed a new USB to Serial cable at the suggestion of FAST to hopefully deal with a connectivity issue (likes to drop out when I data log or just hang in general at times)

Share this post


Link to post
Share on other sites

I made the switch while I was snow bound.  Shortly after the switch my battery died (lost a cell) and at the time I blamed the fail to start on low voltage from cranking.  I also added a throttle body gasket at the same time with some longer studs (I was less a gasket as I didn't have enough thread to spare....it did run pretty good less a gasket though)  I pulled it apart last weekend thinking that was the cause of the no start and poor MAP performance (IE a covered port or maybe loose fasteners)  put it together and fired right up.  The MAP readings were poor before this.

I am going ot start checking stuff with a meter this week.  I probed the MAP plug and the ground readings looked a little goofy at the time so I want to double check that and trace back where I tied in for the 5v signal and ground on the fuel pressure sensor (I think I pulled them from the TPS wiring and not sure if it is connected back to the MAP....TPS reads fine)

Share this post


Link to post
Share on other sites
On 3/19/2017 at 8:32 PM, NukeWorker said:

But now my MAP is being spotty.  some days it works just fine and other days it reads a full 99% load / 100kpa while trying to crank it over. 

Hmmm....how does the ECM calculate "load"?   (I thought of this while looking at data on an Aveo that has a wicked surge at 1/4 throttle in drive...most sensors cycle high/low as the engine cycles, "load" included, even though MAP and TPS are very steady.)

Share this post


Link to post
Share on other sites

Lots of factors, the primary being MAP, MAF, RPM, TPS. Other factors such as IAT and CLT factor as well on some ECM. And then there's theoretical load......

Share this post


Link to post
Share on other sites

When looking at the Aveo data and seeing "load" vary high/low just like MAF (while MAP and TPS were very near steady) I wondered how the xFI was "determining" that "load" was 99%.   The Aveo had a crack in the air duct between MAF and TB.  So I assume MAF was it's primary "load" variable.  It would be crappy for Nukeworker to attribute all of the 99% load to the MAP if that sensor might not be that important to the "load" calculation. (FWIW, my TPS was near 20% while MAP was nearly atmosphere.)

Share this post


Link to post
Share on other sites

I think the XFI loading is based on RPM and VAC.  so if at idle I have a MAP reading of 101kPa then it shows it as 100% load.

 

Anyways...

 

The Update:

 

Truck fired up fine on Thursday evening.  gave a code 20 (which breaks down to a MAP and WB error)  did a key reset and all was well.....kinda.

 

Warmed it up and scooted around the neighborhood coughing and spitting.  Noticed that once warm it wasn't kicking into self learn.....then noticed my 12.5v reading.  so the alternator I put on in fall died with like a whopping 5 miles on it.  Also turns out that the XFI will not self learn if voltage is below 13.0 volts or so.  Swapped the alt out and am showing 14.8v at idle (seems a little high to me) but have had family in town over the weekend so I can't get it out to see if it will self tune now.  I did put some more fuel in it in the 1400 column as it was bucking pretty bad and showing over 16:1 at cruise.  that smoothed it out some.  Still hoping to get some drive time this evening and see how it does.

Share this post


Link to post
Share on other sites

Self learning on the xfi isn't too great.  Don't rely on it much.  I'm sure you know that the ecu interpolates VE from the 9 cells that the bubble is touching.  Well if all 9 are lean, it will add fuel only to the one that it's over the most.  So, it can make you have a few cells that are way out of wack from the others.  Pressing "G" when looking at the ve table will pull up a 3d graph and you can visually see how smooth it is or if there are odd peaks and valleys.

Share this post


Link to post
Share on other sites

So an update:

 

Drove it again last night.  13.5v at idle.....then DROPS when load/RPM comes up.  no idea whats up with that.

MAP is still being spotty I think.  We drove around for 10 minutes or so and then pulled back in the garage.  let it idle for a few checking on things and it started to not rev.....MAP dropping out or something.

I am wondering if there could be an issue with the pushlock hose I am using?  it is only a 3" long piece of -4 but could it be collapsing? or failed internally?

 

I am not trying to rely on it Mike but mostly it is a total pain to try and tune this solo.  I think it might be WAY off even starting with the FAST tune for a Hot Cam 350 (in reality maybe my VE's are much better with the Bowtie heads and single plane?)  I almost am at the point of taking it to the "shop" we have in town to tune and sort it out.

Share this post


Link to post
Share on other sites
19 minutes ago, NukeWorker said:

I am not trying to rely on it Mike but mostly it is a total pain to try and tune this solo.  I think it might be WAY off even starting with the FAST tune for a Hot Cam 350 (in reality maybe my VE's are much better with the Bowtie heads and single plane?)  I almost am at the point of taking it to the "shop" we have in town to tune and sort it out.

I completely understand.  I had a hard time doing mine myself.  I just had to go out and datalog with o2 correction turned off then make changes.  It took about 8 trips before I got it close to something I would drive without worry.  I'm not sure I ever got the WOT dialed in.  It was always rich.

Share this post


Link to post
Share on other sites
1 hour ago, NukeWorker said:

 

I am wondering if there could be an issue with the pushlock hose I am using?  it is only a 3" long piece of -4 but could it be collapsing? or failed internally?

 

I thought you had a vacuum pump and could check it that way (eliminating the questionable hose)?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.