starting L69-350 my plans with questions

[84HOtransam]

I am about to start the process of pulling my stock L69 and replace it with a non computer controlled 350. I already have a mechanical water temp gauge and I would like to keep the stock volt meter and oil pressure gauge. I am removing the computer and all its wiring. I have no idea where to start. The motor going in has a Holley 750 DP and non computer HEI distributor. I am going to set it up with an electric water pump and alternator run right off the crank where the power steering pump is now.

So is it possible to remove the computer and wire harness and still have my gauges, radio, electric fan, lights and wipers work?

I also want to lose the rest of my vacuum lines and canister I don’t need anymore as well as the oxygen sensor (new headers don’t have provisions) .

What else can go?

Has anyone done this type of swap before?

In general I want a clean and professional looking engine swap. The car is not a daily driver and primarily track/ limited street use (to and from track). The front suspension is Lakewood 90/10’s with new moog springs. Rear is a 9in with 4.30’s and a Detroit trutrac. Lakewood 50/50s and new moog springs. Spohn lca’s and panhard rod. Stock torque arm for now. (Ill install bmr trac pak after the sub-frames are in) I run 15x3.5 front rims with 165 tires and rear 27x10.5 qtp’s on 15x8 rims. Alum. Drive shaft and stock non wc bw t-5 trans. Centerforce DF clutch and hurst shifter.

Im going to install hooker super comps 1 ¾ coated headers with dual 3in cutouts into a 3in x pipe and hooker mufflers and have side exit exhaust before the back wheels.

I have a heated, lit garage that I can store the car in for as long as I need as well as an engine hoist and stand, hand tools, air tools, welder, torch, jacks, and ramps.

Am I missing anything?

[V]

im most computer controlled engines, there is a seperate engine harness from the underhood harness. i know thats how its in in MOST car, but i have dealt with an 86? iroc that had the harnesses mixed, but theres still one main part that can be removed. With gauge wiring on your 84, it is all in the underhood side of the harness, and not through the computer. To remove the computer harness, first remove the computer from over the passenger footwell and unhook the harness and pull it up through the fender and into the engine compartment, pass the blower motor. That main harness now can be unplugged at one connector at a time. Fans will not function as stock however, they are usually computer controlled. radio, lights and wipers will eb completely unaffected as long as the main power wires off the starter are left intact. Once the motor is out and you can easily access the engine compartment, youll get a better idea of what can be removed, obviously try to label connectors when you pull the motor. You may have to remove some factroy wiring loom the seperate all the wires and seperate harnesses. most of the vacuum lines can be removed, main ones youd need are to brake booster, vacuum canister, pcv, dist. advance(if used) and climate control system. The T5 setup you are using, is it mechanical or hydraulic clutch setup? i ask because if its a hydraulic version with the tilted belllhousing, the Long tube headers will interfere with the clutch slave cylinder.(the manual linkage clutch may also have clearence issues, but i dont know) I may have missed a few thiongs with the wiring that may be year specific(82-84) but overall thats basic stuff for the later 3rd gens that ive worked on/dissassembled.

[Batman]

On an 84 I would think everything is mechanical still so you shouldn't have any problems. I don't think the wipers, lights or radio hook to it in anyway but the electric fan (Are you sure it is electric on an 84?) is probably going to be hooked to the PCM so plan on having to work that issue when you get there. I know on the newer 3rd gens it hooks to the PCM and is controlled by the PCM but I am not 100% sure on an 84 because it is the older computer. If you pull the ECm then you definately won't need an O2 sensor. Not sure on the canister controls for you.

[84HOtransam]

Single electric fan is stock on the L69...i also added 2 fans to push air on the front of the radiator.

Ill take care of the fans with a seperate thermostate.

the trans setup is the stock hydrualic that came in the car. i have been reading up on the clearence issue. i will just cross that bridge when i reach it..

[Savage_Messiah]

probably be easiest to wire up a manual fan switch to address that issue

[NJSPEEDER]

my suggestion would be to get the motor and sending units all installed in the car and hook up all teh appropriate wires. any wires that are left over you can just chase out of the harness.
jsut get the engine started before you cut anything up.

it takes a little time, but you will be sure to not have any unneccesary wires weighing the car down :)

[84HOtransam]

my suggestion would be to get the motor and sending units all installed in the car and hook up all teh appropriate wires. any wires that are left over you can just chase out of the harness.
jsut get the engine started before you cut anything up.

it takes a little time, but you will be sure to not have any unneccesary wires weighing the car down :)

i was waiting for a reply from you..thanks..it sounds like a good idea.

[helgrind]

I just removed the ecm, all related wiring, and the smog stuff.... really simple... should take only a few hours. unplug the ecm wire harness at the ecm, pull out through hole in fender then just have your way at un-plugging all the crap. wipers, radio, etc have nothing to do with that. your speedo should be mechanical so thats a no-brainer. tach doesn't run off the ecm so thats ok. as far as fan control goes I wired up a temp. switch to a relay that turns on the fan when the temps get hot, only runs when the car ign. is on. i don't remember about the temp sender but i removed the stock cluster and have a mechanical water temp and oil pressure gauge. oh your fuel level gauge will still work too.

[camaro2you]

haha just did this swap on my car this past week still working out some bugs but its stupid ****, rerouting a fuel fitting a different way getting shorter plug wires and such. send me a pm if ya need any pics or info on anything.

[84HOtransam]

haha just did this swap on my car this past week still working out some bugs but its stupid ****, rerouting a fuel fitting a different way getting shorter plug wires and such. send me a pm if ya need any pics or info on anything.

are you using the accel shorty plugs with those headers? do you know what part number they are?

[Tru2Chevy]

Anything that is plugged into the ECM can be pulled out with no ill effects (besides the electric fans). For the fans, I would just toss the fan switch in the head and wire it up that way.

- Justin