Cadillac 500 to TBI

I'm new to EFI conversions and I have a big project with hopes of finding help here. I have a 1986 Chevy4x4 that I'm swapping in a cadillac 500 motor and a 4L80E transmission. I am converting the 500 to TBI froma chevy 454. I have the throttle body and adapter. A brand new engine wiring harness for a 1992-1995chevy truck. Some of the sensors. A cadillac engine to chevy transmission adapter. The PCM I think I need is the 16197427 to control the tbi and transmission. I know there's more parts I need but it's a start.
Hope this site can help me with what to do and what I need. Thanks

The 16197427 PCM is great and has lot's of support and all files needed for TunerPro and so many hacs for running TBI, MPFI and even MAF. It usually runs mask ID $OD for 4L60E which I think can be changed to 4L80E. But you can just start with a $OE mask bin/chip that was designed for the 4l80E in the same PCM.

1986 Chevy truck was carb but should have a VSS already in behind the speedo so that's a good start to. There's lots of guys here that can help out details of VSS changes needed when you get to the chip burning stage.

Post some pictures of your buildup as you go, we like to see projects come together! :rockon:

Mark is correct , there should already be a provision for a speed sensor behind the cluster .

The '7427 is by far the one to choose for this type of conversion , as Mark said , switch to $OE and start with a 454/4L80E bin , should put you pretty darned close .

You will need to address the distributor , I used a early CC distributor when I did the 403 in my Olds and modded the wiring to suit , I believe they are out there for the Cadilliac also .

Good luck with your swap

TOM

Distributor! Good point! If you can get a large cap HEI for that engine it can be converted to EFI spark timing control fairly easily... if not there are other ways.

One other thing to think of is fuel. 500 cubic inches can use a lot and a TBI fuel pump may not be enough. You can use an inline TPI fuel pump which is widely used with big inch or big HP engines. Need 3/8th line to feed and 3/8 or 5/16th return.

I used the 7 pin (I think) CC distributor on my 403 conversion , wired the 4 pins into the control side of the module and retained the coil in cap . At least that is how I think i did it , it has been quite some time ago....

1986 should still be carbed , but he could replace the tank and sender with a later ('87-up) injected tank and I would install an intank TPI pump , no more $ than the TBI pump and it'll give you all the fuel you will need .

TOM

Here's a thread with that HEI conversion info...

http://www.gearhead-efi.com/Fuel-Inj...BI-on-inline-6

I forgot to metion that I also have a distributor out of a 1980 cadillac eldorado with a fuel injected 368 motor. I read
that it should work with some modifications.

Sweet! That should be the large cap HEI with 7 pin module? Like one pictured in other thread? I'm not familiar with what came on them but that is the type of that era...

If it is going into a non-EFI tank, I would suggest the newer style fuel pump module. Like here:
http://www.gearhead-efi.com/Fuel-Inj...l-Pump-Upgrade

Pretty easy, cheap, and will support lots of power.

Thanks, I'll look into it.

Haha, the caddy 500. I have one of those in the storage shed, disassembled, in need of a rebuild. I have plans to one day build it and swap it into my cherokee, but money has kept me from doing that. Plus my current 401 is only a few years old on a full rebuild, so I will probably wait untill I wear it out. So I may be 50 by the time I swap it in (I'm 29 right now)...lol

I remember a build on one of those several years ago in a hot rod mag, they built it and it had more HP, an just as much torque as the customers duramax diesel. I think I still have that issue somewhere....

Those big caddy motors have always been huge tourque monsters! Pushing a 6000 brick down the highway at 70 MPH effortlsly, just touch the gas and 100 MPH comes around. Of course gas was a lot cheaper then, but that was not even a point to a Caddy owner!

I hope we still have gas by the time your 50! But there's enough scrap metal there to build a new car...

Today while at Pull&Save, we found a '74 Eldorado, with a 500 and FWD TH425. My dad and I want to take the front half of the frame from one and graft it the back of the front half of a Datsun pickup. So we would have a rear engine pickup. And of course EFI it.

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Originally Posted by gregs78cam

Today while at Pull&Save, we found a '74 Eldorado, with a 500 and FWD TH425. My dad and I want to take the front half of the frame from one and graft it the back of the front half of a Datsun pickup. So we would have a rear engine pickup. And of course EFI it.

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Now that would be cool!

Next time you go to pull and save let me know if you have room for one more, if not my wagon will seat 6 and still carry all the parts back!

Quote:

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Originally Posted by EagleMark

Now that would be cool!

Next time you go to pull and save let me know if you have room for one more, if not my wagon will seat 6 and still carry all the parts back!

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OK!:happy:

That is how I bought my 500. The guy cut the frame just behind the transmission and welded on a
pipe with a hitch to move it around the yard. I still have the frame, transmission and axels.Attachment 1555Attachment 1556Attachment 1557

wow, frame, trans and axles is exactly what we need, we already have a 472 to fit it.

Found the mag. Its the april 2008 issue of hot rod.
They did a few tricks like offset grinding the crank to the BBC size, 7 inch rods, .075 overbore, for 541 CID.
They added some custom aluminum heads, cam, rockers, etc...
649 ft/lbs or torque at 3400rpm and 526 hp at 5000rpm.
:rockon:

Quote:

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649 ft/lbs or torque at 3400rpm

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:rockon:

What does a Cummins diesel do? Stock...

Going to the first site I found on google, it has a very wide rating over the years. Based on if its a 12 valve, or 24 valve, crd, etc..
But according to the site I found,
A 2000 model manual trans listed 235hp at 2700rpm, and 460ft/lbs at 1600rpm.
A 2001 high output model lists 245hp, and 505ft/lbs at the same rpm's.
02 and 03 high output models showed 305hp at 2900rpm, and 555ft/lbs at 1400rpm.

:happy:

Built Caddy motor beats a cummins diesel.... :thumbsup:

HAHA stock '70 caddy motor beats '00 Cummins.

But not a built cummins....lol

I wonder what kind of numbers a caddy 500 would put out without the mods done in the hot rod build.
Say stock crank, rods, and stock type pistons, mabey a .030 overbore (typical rebuild) mabey do a light port/polish to the heads and 3 angle valve job, mabey a mild or rv style cam, aftermarket 4V intake, headers, etc...

Is there anyone on this site that could modify a wiring harness? I have a brand new harness from a 1994 C/K chevy truck.
I'm sure it has way more connections than I need.

It's a time consuming task but not hard. We have wiring diagrams and have just been offered a way to update what we have to newer and better. You sure you don't want to do it yourself?

I just re read this thread and informed you that your truck should have a VSS in speedo. It is 2 PPM and in another thread been told that will work with the TBI but for the 4l80E you need 40PPM and it should already be in the trans.

Does your harness have the 4l80E wiring?

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Originally Posted by EagleMark

I just re read this thread and informed you that your truck should have a VSS in speedo. It is 2 PPM and in another thread been told that will work with the TBI but for the 4l80E you need 40PPM and it should already be in the trans.Does your harness have the 4l80E wiring?

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I was just going to say this, the 2 PPR signal will not be able to control an E trans, but the 4L80E will already have the 40 PPR tone ring installed.

I may do the wiring myself. Do you just cut off the ends you don't use or do they have to be removed from
the harness? It has wiring for the 4L80E transmission and I'm going to be using that trans. What way have you been offered to update what you have to newer and better? The truck is all apart in storage and under cover outside under 12" of
snow we got last week here in northern WI. or I would post photos. I'm just getting things together for when the weather gets better. I will post some photos of my wiring harness latter today. Thanks

Just better pictures of what we have for that PCM and other pictures for ECM/PCM we don't have.

I take off all convoluted covering and remove what is not used all the way back to PCM and pull pin or if EGR leave wire as it can be used for wideband on your PCM. There are also going to be a huge harness over to driver side bulk head plug that most is not used but does get power from there. Lots of extras like air diverter, altenator, etc... lots of factory splices for power and grounds, leave them and just cut wire inside where they are taped.

Basically lay the harness out so all connections on motor are where they are supposed to be. Your's has rear distributor like chevy so it should be pretty easy, wires going to PCM, then in middle is all the work where relays are needed, power from fuse block on driver side being removed and things like trans harness and fuel pump wire comes out to go down away from engine harness.

Couple things stay inside cab from PCM connecter like ALDL port and Check Engine Light.

One wire at a time! Just take your time!

When done just use a few cable ties and install harness in truck so things can be adjusted, then tie, tape and run engine, then when your sure it's done put the convoluted tubing back on and you can incorerate your existing harness into it for a clean look.

If you have all the sensors and TBI you can hook up to power and turn distributor with drill and run it on the bench. In the end you should have all plugs and a 12 volt power wire, your wire to you points with resister removed will go to pink wire to power relays and turn on system, 2 grounds and fuel pump wire to hook up.

Here's some ideas:
http://www.gearhead-efi.com/Fuel-Inj...Engine!-HOW-TO!

Here are some photos of the wiring harness I have. I'm sure I won't be using all the ends.Attachment 1826Attachment 1827Attachment 1828Attachment 1829Attachment 1830Attachment 1831Attachment 1832Attachment 1833Attachment 1834

Can a person use a Holley Commander 900cfm 4bbl throttle body with a GM PCM, wiring and sensors? Like this one.Attachment 1835Attachment 1836Attachment 1837

You could, but I wouldn't.

I worked on one once that was bought from and aftermarket EFI company, it had all the injector wires cut and fired right front and left rear and vice versa on a stock ECM. It never ran right untill we put a BB TBI on it. Here's the information on why it won't work and how to make it work.

http://www.dynamicefi.com/InjectorDriving.php

Remove the injector pod, cap the fuel lines, and use it for MPI. :happy:
:innocent2: