i have the hei distibutor from my 350. can i install it in my 472 and do away with the damn coil system. thanks
Printable View
i have the hei distibutor from my 350. can i install it in my 472 and do away with the damn coil system. thanks
The shaft length is the same between the caddy an chevy but the body is a different length and diameter where it drops into the block. Because of the larger diameter of the HEI cap there is a few inches between the block and body to clear the AC compressor. Another issue you may have if you still have the AC compressor is that the inner of the dual belt will rub on the cap. When they went to the HEI they switched to a wider single belt to clear the cap. If you are not running the AC anymore you can just remove it and run a shorter belt(s) straignt from the crank pulley to the power steering pump. It will clear the water pump fine. If you motor has the smog pump you will also have to put a slight dent /bend in the tube that goes between the heads. A few of the performance people make dizzys for these motors. The 472 68-74 ,500 70-76, 425 77-79, and 368 80-85. Were all the same basic block so the dizzys will interchange. The basic HEI got phased in starting in 74. All 75-79 were HEI’s with mechanical and vacuum advance. Starting in 80 some of them were computer controlled timing so they did not have the weights. 75-79 there was an EFI option for those motors the top side of those dizzys is the same only difference is there is a sensor in the stalk that gave a tach signal to the ECU to fire the injectors. Only other catch is the 75-80 seville and 79 eldorado used the 350 EFI Oldsmobile motor so those wont fit your 472.
Hope this helps
it does charlie. i have already removed the ac and the smog crap. my engine is a 71 472. it that makes a difference.
my distributor is a msd hei. it does not want to sit all the way down to the block. can someone recommend a hei distributor that is good but not very expensive?
Barb----how about bringing us up to date on EXACTLY what parts are on your car and how you have them wired???
Points???? Hei????Msd????? Msd dist????Msd box?????
you need help barb .. wish i were closer to you ..
i had a coil wired to a points distributor. i have a msd hei distributor off of my 350. it does not fit. i really want to get rid of the coil system. my coil is wired to my ignition along with the electric choke from the carb with new wire. the - on the coil is wired to the distributor. i put all new spark plug wires and spark plugs on the engine and a new coil wire. i even tried running a wire to my fuse box on the ignition fuse. it was no different. i pulled the coil wire off the distributor and put a spark plug in it grounded to the block. took a wire to the + side of the coil and got a spark off the battery directly. the spark plug did not spark. it is a new coil. just tired of being hung up on this mess. the coil is wired to my pink wire coming off my ignition.
take the wire to the choke off the coil!!!!
it is not on the coil it is wired with a wire nut with the coil to the ignition. but i will take it off tomorrow. i really appreciate all the help with this. i know you guys are getting tired of me bugging yall over and over with the same problem.
thanks tech
Hey Barb,Dont ever think that we are tired of your questions. We all feel your frustration,please keep pluging away at this and dont give up.
This should help to wire your Points Dist . A Friend passed it on to me .
thanks tango and chopped. but i am going back to hei. found one by dui for my engine. now i am selling my wii to pay for it. but i did find out today that i had the points wired correctly. my brand new advanced auto coil is crap. had a friend come over that knows coils and he tested it out by wiring it directly to the battery and got no spark either.
You will not get any spark out of the coil with the electric choke wired to the same circuit as it creates a dead short to the voltage
took that off jerry and still nothing.
he took the coil and disconnected it from everything. he then took the coil wire and put a spark plug in it. he put a wire to the - then another one to the + and put those wires to the - and + to the battery. he grounded the spark plug to the block. the wires sparked but the coil did not. I am taking the coil back to get my money but i really want to go back to hei.
Barb---you been jumping back and forth from the points to hei----do you know that the points plug gap is a lot less than the hei???if your gapped wide you might not get a spark--
ALSO----you are doing something very basic wrong---and from your replies I don't think you understand what we are trying to tell you--there are some very simple basic checks and if you think the coil is bad, why don't you try the original one???
i am gapped by the caddy book to coil specs. the old coil had a crack in it. that is why i replaced it. now i have another question. i have the hei distributo from my 350. the gear on the hei does not fit in my engine. can i change the top part of the hei by installing it into the points one. the lower unit is the same diamater.
The housings are different and I suspect the driveshaft is a different length. With enough time and patience, I suppose you could do it, but there is a better way. Call around to your local boneyards and find a HEI from a '75 or '76 500 CID motor. Same motor as yours, with a little longer stroke. Make a deal with the boneyard that the distributor is guaranteed to make fire or they will exchange it for another unit that will work or refund your money.
Begin with all spark plugs and the distributor removed from the motor. There seems to be some confusion as to what is #1 spark plug. I'm thinkin' that it is the front plug on the passenger side of the motor and that the firing order is 1-5-6-3-4-2-7-8 with the distributor rotor turning clockwise. 1-3-5-7 would be on the passenger side and 2-4-6-8 would be on the driver's side, just bass-ackwards from a Chevy. Is that what your service manual shows? We need to get this nailed down before going any further.
you are dead on tech with the firing order and odd on the passenger side. backwards from chevy. i will call around tomorrow to see if i can track down a distributor. the junk yards are closed here for the day. thanks tech.
OK, put your order in at Summit for one of a Moroso 26140 HEI shim kit...
http://www.summitracing.com/parts/MOR-26140/
These are steel shims meant to be used at the bottom of the distributor between the gear and the housing to reduce shaft end play. They are not to be confused with nylon shims that are meant to be used where the distributor housing meets the intake manifold. Those nylon shims are used to restore the depth of the distributor gear into the cam gear following having material removed from the cylinder heads, block and/or intake manifold. Here is the blurb from Performance Distributors....
"The HEI does require some end play but nothing too excessive. We shim our distributors with 0.025" - 0.030" of end play. Any tighter than 0.025" can cause excessive gear wear and more than 0.030" can cause timing fluctuation."
Here's a piece I ran across on the net that shows the procedure for disassembly and assembly of an HEI. This guy sets the end play at 0.010". Performance Distributors says 0.025" to 0.030". I would listen to Performance Distributors, as they have done thousands of these. I would take your boneyard HEI apart according to your service manual and this tutorial and make sure it is a player before dropping it in the hole. Get some silicone oil to re-wet the felt that lubes the bushing.
http://www.rustpuppy.org/ignition2/Ignition%202b.htm
http://www.airsplat.com/Items/AC-TAG-SILICONE.htm
Crane makes an adjustable vacuum cannister and limiter plate that works well for dialing in the vacuum advance. The part number does not show working on a Caddy HEI, but I don't see how there could be that much difference in the upper end of the distributor.
http://www.summitracing.com/parts/CR...EVROLET&page=1
This will be a good time to verify the validity of your harmonic damper TDC mark on the inertia ring. The damper is made of 3 pieces, the inner hub which press-fits onto the end of the crankshaft snout, the black rubber-looking elastomeric material that allows the inertia ring to twist, and the inertia ring itself. Allowing for time and the harsh environment in which the damper must operate, the elastomeric material can break down, allowing the outer inertia ring to slip circumferentially in relation to the inner hub that presses onto the crank. If the inertia ring slips, you no longer have a reference to top dead center to ignition time the motor. Here is a company that will disassemble your damper and install new elastomeric material while clocking the inertia ring back to the hub properly.
http://www.damperdoctor.com/Merchant...egory_Code=CAD
And by the way, resist all temptation to purchase an aftermarket damper unless you need an SFI 18.1 damper to go class racing. The aftermarket damper units I have seen are bored incorrectly and are either too tight to press onto the crank snout or are too loose. The hub must be the correct press fit onto the crank in order to transfer vibrations (harmonics) to the inertia ring to be cancelled out. That's why they're called harmonic dampers. (They dampen harmonics if fitted correctly). When a piston fires, the force is transferred down the rod to the crankpin, which is offset from the centerline of the cylinder bore. This force twists the crank. The crank will only twist just so far until it meets resistance in the core of the crank. It then springs back the other way to its limit. Then back the other way, then back the other way. All of this bending back and forth happens very rapidly and can be likened to plucking a guitar string. If the back and forth harmonics are not cancelled with a damper unit or blower drive belt, they can crack the crankshaft. You know without a doubt that the OEM damper has the hub bored correctly or it would not be sitting on the end of the crank in the first place. It would have been scrapped at the factory. That's why I like to have Damper Doctor rebuild my stock, OEM damper. I know the hub is correct.
Now, if the inertia ring has slipped and you don't want to spend the money for a rebuilt damper right now, here's what I would do. Remove all the spark plugs. Turn the crank with a socket and bar on the damper retaining bolt in the end of the crank. Have a friend hold his/her thumb over the #1 spark plug hole while you turn the crank clockwise. When your friend begins to feel compression being built in the cylinder, have him/her shine a very strong flashlight into the cylinder through the spark plug hole and watch as you slowly bring the piston up to top dead center. This won't be scientific, but it will get you close enough to fire the motor. A mechanic's mirror may be helpful. It's about the size of a quarter and is on a telescoping stick, sold at Checker Auto. When you get the piston to what you think is top dead center, you can install the distributor with the rotor pointing in the direction shown in your service manual and re-install all the spark plugs (AC #44). Gap them to 0.042"-0.045" for the HEI. Some folks will recommend a wider gap, but try them at this first. We're not fine tuning right now, we're just getting the motor running. Using a bright color of paint and a toothpick, make a mark on the timing tab that is attached to the front cover and also on the inertia ring of the damper so that the two marks coincide to mark TDC.
Just for the benefit of those of you who have never done this, there are 720 degrees of crankshaft rotation to make a complete 4-stroke cycle. In other words, the crankshaft rotates two complete turns to fire all 8 spark plugs. If you are attempting to find TDC on the firing cycle, you will need to do the thumb over the spark plug hole trick to feel for compression if you don't have the valve cover off the motor. If you have the valve cover off, you can see when both valves are on their seats and the piston is coming to the top.
There is another time that the piston comes up to the top on the other cycle, but it is with the exhaust valve open (on the exhaust stroke). If you ignition-time the motor off this exhaust cycle, the motor will not run. Both valves must be closed and the motor must be on the compression/firing cycle with the piston coming up in the bore to make compression. I see this happen every day on one forum or another, where the OP has stabbed the distributor into place and has run the wiring with the piston at TDC on the exhaust stroke.
thanks tech. i ordered the summit shims and will go over thoroughly all the info you gave me. found a distributor for a 75 caddy at a local yard for $100.00 with a 60 day warranty. hubby going to pick it up saturday for me. thatnks again for all of your help with this.
In the meantime, chase down the hot wire that used to power the coil. Run it back to the starter switch and remove it. Replace it with a 12/10 ga wire that connects to the start/run terminal of the switch and goes directly to the plus terminal on the HEI. If you have to run the wire from the fuse block because you cannot get to the switch, make REAAAAL sure that the wire from the switch to the fuse block is not a ballast wire (a resistance wire that will cut voltage to the HEI when the wire heats up). Eliminate all other ignition wiring that is in the car.
If you have to order an original Service Manual for the Monte Carlo in order to get this whole mess sorted out, then go for it. Faxon Auto Literature.
i have all that wiring in place as my old engine was hei.
if it aint running in three weeks i`m coming up there .. i`m off two weeks for thanksgiving as well as christmas ..
thanks you two. you can still come even if it is running and take her out and let her rip.:D
Barb, I just noticed that the Monte is a '71. That would have come originally with a points ignition. Just because you were running an HEI on the motor does not mean that there is not a resistor wire coming off the switch, unless you or someone before you removed the wire and ran a genuine 12 ga or 10 ga wire. Be careful here please and double check the wire from the switch. Thanks. I don't want to see this boneyard HEI lay down on you as a result of insufficient voltage.:eek:
Barb, just few comment to add to what has been put out there. I'm not trying to sharpshoot anybody and hope nobody takes it that way, I've just been living these engines the last year and they are a bit of an odball with a few quirks.
As far as a an HEI distributor, the 75 and up 472, 500 AND 425 are a direct drop in and you can pick up a reman from rock auto for $115 plus shipping (makes the JY one sound a bit high to me). Which ever way you go make sure you get one with a vacuum advance as these are the ones that are NOT computer controled.
All the internal parts from the a Chevy HEI, distributor cap, rotor, coil, mechanical advance parts and module interchange with the Cadillac unit. The Cadillac HEI are not known to have an optimum advance curve so the distributor recurve kit with adjustable vacuum advance like Summit sells iis not a bad upgrade if you want to play with getting the optimum performance out of the Caddy engine......THAT BEING SAID THE CADDY HEI UNIT WILL DROP IN AND RUN PERFECTLY.... YOU CAN JUST GET A BIT MORE POWER OUT OF THE EGNINE BY FINE TUNING THE IGINITION.
UNLESS the timing tab or lower pulley has been changed there is no need to worry about verifying the timing mark which is a notch located on the innner most ring of the lower pulley. The big Cadillacs use a crank hub like an FE Ford with fits on the end of the crankshaft, the harmonic balancer is a seperate piece that sandwiches between the hub and pulley and then the pully is bolted to the hub. Basically it is impossible for the timing mark to slip on these engines.
Now having said that I did notice in one of the pictures you posted that it looks like you are not running a smog pump and unless your 472 is a 1970 (one year only) your belt setup should look like the first picture. If you are running with a 1970 belt set up which deletes the smog pump (picture 2) chances are that the lower pulley WAS changed. The timing tab would have had to be changed to match the new pulley for the timing marks to be correct.
The simplest way I’ve found to verify the timing marks is partially as Richard say, pull number 1 plug and put a finger over the plug hole while turning the crankshaft over with a large wrench. When you start to feel compression you know the piston is coming up on TDC and getting ready to fire. I normally use a long screwdriver at this point. Gently put it down number 1 sparkplug hole until it contacts the top of the piston and slowly continue to turn the engine over until it reaches the top of the stroke (you can feel when the screwdriver starts to drop meaning you have just past TDC. Check the timing marks at this point and they should line up. If they don’t remark the pulley with the new timing mark.
Thanks for the heads-up on the damper Mike.:D
thanks mike and tech. i will check the wiring. i am not running a smog pump as i removed it and all its piping. my engine looked exactly like the first picture when i got it. i also removed the ac pump. the wiring for my hei was done when i got it. i will have someone that knows wiring better than me to check the gauge of it. thanks again.