El Camino Central Forum banner

81 build, jpe

5K views 63 replies 9 participants last post by  78 Elk 
#1 ·
Hi,

A new member from Finland joined and planning to start a 81 build for a street and occasional street car drag event use . This is not my native language so please forgive my typos.
The car has been sold as new here in Finland and we actually do have quite a bit 5th gen Caminos here. That's because in 80s they were relative cheap as they were sold as tax free delivery vehicles. At 80s we did have about 100% tax on top of factory price for normal passenger cars, nowadays it's a bit lower but still a lot. The car did originally have a V6 and most likely th200. During winters we have have normally quite a bit of snow here and they are salting the roads so rust issues are more than likely for older cars. Also this one have had quite a bit of issues and some earlier owner has replaced basically the whole underside of the car with sheet metal and not very nicely.

The owner before me did also spend some serious money for this as the motor was replaced for a factory new Goodwrench 350 and also the trans is brand new TH350 with some shift kit installed. Also all brakes were renewed as well ass diff with some anti spin lock and about 3.55 gears. This has been some serious money as we need to ship and import these parts from States. Shipping itself is pricey and on top we need to pay about 30% taxes when importing.

However as the body and floor repairs are not done very well there is no any big reason to try to keep the car original anymore so I did buy this for a build project for next winter. The plan is to build a relatively fast street car which is not very easy task here as we do have mandatory yearly inspections for street cars and if you are changing for example a motor you need have approved inspection for a change also. We also have quite a bit of rules what you can do and what not, so this will be interesting journey to see if I'm able to have this inspected after changes.

I've been collecting a bunch of parts for this already and I'm starting to pull off the motor in a week. I'll sell the motor as it does have quite goo resell value here and there is no point to mess this engine as it is very well working one for some cruiser. So at least the motor and rear end will be changed. Maybe the tans is usable at least as long as it holds the planned engines torq. The motor will be iron block truck LS with a quite big turbo. So yes, this will be another LS swap but first one for me. However I still hope the build still interests most of you. Motor will use stock wiring harness and stock ecm with boost os patch, at least that is the plan. Rear end will be Ford 9 inch with 31 spline Strange axles which I already have. The axle will be shortened and all brackets will be planned, laser cutted and welded if I don't find a reasonable priced ready made bracket set. Frame will most likely be boxed and some ways to drop total weight will be inspected. Interior will most likely remain stock for most parts but a roll bar or cage will be in the build list. Maybe a fuel cell etc but we'll see during next winter.



Wheel Tire Car Land vehicle Plant
 
See less See more
1
#2 ·
Welcome aboard from an almost fellow Finn.
My parents hail from there.

I will be following along and look forward to your updates.

And, here I thought we were getting screwed for costs in Canada.
I guess it is worse in other places.
 
  • Like
Reactions: jpe
#5 ·
Hi jpe, welcome from Idaho. Glad you've joined us. Thank you for your introduction. You have a very nice looking 81 El Camino. Looking forward to seeing your build progress. Have fun with your 81 El Camino and the community.
 
#6 · (Edited)
Thank you all!

First a little bit some nerd stuff about the ecm operating system and also about the motor.

The engine is LQ4 with all accessories out of 2003 local wrecked Suburban that should have about 55k miles on it according to seller. After dropping the oil pan I don't buy the miles, but seems to be usable however. Dropped the pan also to check if it has older or newer style rods and they are older style. So the build is limited to about 600hp for now as long as I'll replace rods and pistons later maybe.

Motor vehicle Automotive design Automotive exterior Machine tool Engineering



As said the plan is to use stock ecm and wiring harness which also came with the motor. To be able to handle boost with stock ecm you need to have ve tables etc expanded for 2 or 3 bar map sensor. There is a boost os patch available for P59 ecm operating system 12587603, so one of the first thing I wanted to do was to check if I'll be able to use boost os:

To check the os ecm needs to be powered up and also supported OBD2 connection is needed. Luckily there is a person in my home town who imports supported OBDLink bluetooth dongle, so it was easy and fast to get one.

The wiring loom however did not have a fuse box with it, just the big fuse box connector and it's not very easy to get a 2003 Suburban fuse box here as it's not very common truck here at all. Luckily again there are huge amount of information available nowadays in internet, so it was easy to get knowledge how to power up the stock loom with out fuse box.


Dvi cable Light Automotive tire Hood Motor vehicle



All you need to do is to connect all orange wires to +12V and all pink wires through the on/off switch to +12V. On top of that you need of course to connect all wiring looms ground points to battery negative. After that you are able to power up the ecm using the on/off switch.

Pliers Circuit component Nipper Wire stripper Finger



Ok after I was able to power up the thing I realized that the wiring loom lacks OBD2 connector. Again a bit luckily a local parts store did have a OBD2 connector body and pins available so I did drive there and bought one. Then back to internet and again it was quite easy to find what to connect. ODB2 connector has basically only 3 wires, plus an minus 12V and serial data pin from ecm. It was quite easy to find the correct connector and pin where the serial data is available.

Electrical wiring Automotive tire Auto part Cable Electrical supply



Ok now I was able to connect my OBD2 bluetooth dongle to wiring loom and power up the ecm. Using android app LS Droid I was able to get a working connection to ecm just to find that my operating system 12579405 is not supported by boost os nor there is any support for free TunerPro tuning software.

Font Material property Display device Electronic device Software



Ok back to internet again.

To be continued..
 
#7 · (Edited)
By joining pcmhacking you are able to find some emc operating system files and tuning files for different vehicle - motor - trans combinations and there is 12587603 os with LQ4 tuning and Tunerpro xdf included. It is for 4L80 transmission, but discussing with a person with more knowledge it should not be a problem. My wiring harness actually do have connectors for these later transmissions, so the os will be ready if I'll change the trans later. For now I'll only disable all alarms regarding the transmission and it should work OK with older Th350 or Th400.

So I did upload 12587603 os to the ecm and the process was successful with pcmhammer.

Font Parallel Paper Paper product Document


After writing the new os I did connect electrical throttle pedal and the controller box included in wiring harness to the motor and everything seems to work fine. To me DBW throttle calibration seems ok. So it seems it could work without aftermarket ecu but well see later when I'll try to fire up the motor. Before that ring gaps will be enlarged for boost, bearings checked etc.



Next I'll start to lift the old motor away and the actual build will start.
 
#9 ·
Thank you!

It would be too easy, or actually too pricey, for me to buy correct impedance injectors so I did buy a cheap used low impedance set from a friend who needed larger ones. The plan is to use E85 fuel and as said some boost, so injectors must support both demands. Injectors I bought are Holley 120lb/hr and the set came straight from service, so they are just measured, cleaned and serviced.

Camera accessory Camera lens Automotive tire Cameras & optics Auto part



So as the plan is also to use stock ecm I'll need to use ballast resistors or spend money and buy peak and hold type separate injector driver box not to fry ecm injector driver. As this will be relatively low budget build I'll at least try to use resistors first. Injectors were measured as 3.1ohms and smaller the ballast resistor will be more voltage but also current injector will get. If voltage is dropped too much injector opening time will be too slow to properly tune them for idle. Also it's unknown at least for me what is minimum voltage to open them at all. Holley spec sheet tells the lag for 8.0 volts so at least it should work. However 8.0 volts would mean a bit less than 3 Amp current to stock injector driver so it may be a bit too much as with stock injectors the current would be about 0.8Amps.
If someone happens to know how much current stock LS ecm can take reliable please tell me. If injectors would open with about 7 volts the current would be less than 2 Amps and I think that should fit the tolerance. There are also some people arguing that they are running low impedance injectors without ballast resistors with stock ls ecm.


Also following the low budget rule the turbo I bought was very much on cheap side but not a Chinese GT45 however. I did find just only test used Holset HX55 that is actually a Scania freight truck spare part and it was cheaper than a GT45. Again it may be that I'm not doing this very easy for myself but if I'm not totally wrong the turbo should work ok with the motor to reach my targets. But we'll see I guess. At least the hot side will be large enough.


Automotive tire Tire Tread Motor vehicle Rim
 
#11 ·
I did lift the old 350 with trans out of Camino and it is now waiting to have a space in my garage. So there will be a couple week brake before build continues. I need first to move my 72 Chevelle out of the way to it's winter storage and to do it I have couple of things to do with it before.


Car Plant Vehicle Motor vehicle Hood
 
#12 · (Edited)
Hello,

I am impressed!! Very impressed. Your knowledge of LS Droid, Tuner Pro RT, PCM Hammer and the PCM Hacking web site is all very good. Most people tend to use "HP Tuners" for their PCM operating system re-writes and I'm happy to see others use these more obscure but free PCM tools.

I can also suggest that you add another tool to your list: "Universal Patcher". This program has saved me a few times when I've caused myself a checksum error after doing something stupid inside the operating system (OS). UP determines what the checksum error is and then determines what needs to be fixed to correct it. Amazing!! Accept the fix, save the OS file and move on.

Universal Patcher also has a relatively new capability for creating operating system "definition files" . . . aka the "XDF" that Tuner Pro RT needs to interpret all of the parameters inside the thousands of lines of code inside the operating system. I have not used these functions because I stick with the P01 and P59 PCM OS versions that already have richly featured XDF files. This has allowed people to create XDF files for quite a number of the lesser known GM operating systems without having to learn how to use a de-compiler reverse engineering tool such as "Ghidra" or "IDA Pro".

I may have a file or two that can help you with your 4L80E segment swap. Between LS Droid, PCM Hammer and Universal Patcher, we should be able to get you going.

Edit: Ah, OK. I re-read about the 4L80E problem. No need for a segment swap and I would have done the same thing to kill off the 4L80E OBD2 DTC trouble codes if I was using a non-electronic automatic transmission. I've also got a list of my typical trouble codes to kill off for everything if you need it.

Rick
 
#13 ·
Damn, I'm glad I have HP Tuners after trying to understand whatever it is that you posted above.
All I see with all the computer talk is a jumble of wires my friend sees when I work on a harness. o_O
 
  • Like
Reactions: jpe
#14 ·
Thank you! Have to admit that I got some help where to start from a builder also located here in Finland who have actually coded the universal patcher I think. So I have heard also about that but have not took the time and learned it yet.

If you have a list of typical codes to disable it should help quite a bit!

The target is to get everything to work with stock ecm but I am a bit worried about driving those low impedance injectors. If I'll need a peak and hold driver box it would make more sense to use a aftermarket ecu.
 
#15 ·
Yes, you are correct to worry about a low impedance injector. That circuit will appear to the PCM as very nearly a high current "short" - like two wires touching with a near zero resistance. This won't play nicely with the very tiniest printed circuit board traces but there is no predicting how quickly this might or might not fail.

Fortunately, a P59 PCM is cheap around here in the junk yards and if you need another, let me know and I will send you one for an invisibly small price. I have a bit of a hoarding problem with PCM's - I have way too many, I think my stack is eight high of these and the P01 devices.

When I walk through the junk yards . . . I . . . just . . . can't . . . let one of these sit there. Especially when somebody else has been ever so kind as to do the work for me to expose it. Typically, they are about 35 USD for a price around here but I like to go to the yards "for the good walking exercise", of course, on the Half Price Sale Days to see what I can drag back home.

I've never had a bad one coming out of the junk yards but I did have one fail later that caused me a bunch of random spark misfires. It eventually went into the trash at the end of a long period of troubleshooting.

Rick
 
#16 ·
Sounds really good, then there would be quite low risk to try with ballast resistors. Let's see what happens.
There seems also to be still one AEM peak and hold driver box in shop here and they are willing to sell it for 350€ which nowadays is quite a bit the same amount in $. The price here was 550€ but they want to get rid of it so maybe I'll just get it and do not need to worry more if I can get injectors to work. However I may still need a ecm after try and errors.
 
#17 ·
I did drop fuel tank and also rear axle to try fit a GM 12bolt axle I happen to have. The axle has been fitted to G body by someone earlier and I did buy it some years ago quite cheap.
Well it seems to fit to link arms and also springs and shocks ok. Only issue is that the axle is too wide about 2 inches per side. Now I'm thinking should I actually use this axle and create a bit wider body Camino as this now gives plenty of frame side room for 10 inch wide slicks. Another way would be to shorten the axle a bit or go back to the original plan and build a Ford 9 inch one.

I've seen some photos of a wider rear fender Camino and it was not totally bad at all.



Tire Wheel Vehicle Automotive tire Motor vehicle


Tire Wheel Vehicle Automotive tire Hood
 
#23 ·
After a short holiday in Greece back to Camino. I did test a 29*10" Hoosier wheel set with the wider 12 bolt axle and for my surprise they did not push nearly as much out as the stock set in the photo earlier. So I checked the et numbers and my stock wheels seem to have minus 20 et so they do come out a bit less than an inch more than expected. So a bit less modification needed with et0 or even with plus et wheels if I can find a set.
 
#26 ·
Cleaned all pistons and filed ring gaps for boost. Both upper and lower gaps are now 0.7mm which is about 0.028 inches. Motor seems to have some miles as lowers were all actually already 0.028". Uppers were about 0.024" so they needed some work. All cylinder walls seem fine. Also lifters are ok and I'll reuse then for now.


Black Font Gas Tool Wood
 
Top