Need help with 3.5 (was 3.2) Cam Timing, Head Studs, Top End

strictly · 08:46 AM

History

I have bought a 3.2 which has been rebuilt to 3.5. It had a fire, and the previous owner decided to dismantle one half of the engine (left side, 1 to 3) removing the cam tower, cylinder heads, and chain housing (leaving the piston/cylinders on). To check for damage (carb fire (PMO) on left side). All okay thankfully. The right side is untouched with current cam timing unalterated since having been rebuilt.

its apparently got 10,000 miles from having been rebuilt, and I do have a copy of waynes rebuild book, and Anderson, and other manuals.

Goal

I would like to reassemble and see how it runs before i decide how deep i need to go with it, or if at all. I need to figure out the ignition side as welll

QUESTIONS

1) It has 993 head studs - okay to use anti-sieze compound as a lube for the head stud torque? And is anti-sieze the same as copper grease? Or should i search out specfic lube? I presume I am okay to reuse the existing 993 head studs (?), i wasent planning on removing the pistons/cylinders at this stage

2) Is torquing one side of the motor is not a great idea? - should i loosen the right side of the engine and retorque the head nuts, and then redo both left and right cam timing? is there a risk i could loosen the head studs on the right side, or should i just give em a squirt of oil and go for it? if so i'll do this AFTER the question below

3) If i am to measure the cam timing on the right side, which still is untouched with hydraulic tensioner, should i take the tensioner out, and replace with a mechanical one (stomski) or can i MEASURE the cam timing with the hydraulic tensioner fitted?

The idea behind measuring the cam timing on the right, is to help me figure out what grind the left cam is. It has a solex part number (see pic below), so its either solex, or its been ground since. Ive looked it up in waynes book, and have an idea of what it should be based on the part number. I am going to measure the lobes, on the one in my hand (left) and try and measure the lift using a dial indicator for the one on the right, to narrow down the cam. The reason i was thinking perhaps it has had a grind, as its not aggressive enough for a 3.5 on 46mm PMO's?

4) It had crankfire igntion with a tec-3 ecu and coil pack. The coil pack has gone up in smoke, so just to get it to run, im going to fit it with CDI, and a 2.4T Dizzy from my 2.4, just to get it to run.

I will move to either a replacement electromtive coil pack or programmable MSD, once i hear it run.

My question is - okay to time at 35 deg BTDC @ 6000rpm as a basic setting for max advance?

=======

Any advice you want to add just go for it.

Tippy · 05-07-2016, 10:38 AM

1. I torqued mine dry. Reason I did, is because your exact question. Lubricants effect final torque and can lead to overtorque. Being 993 studs are Dilavar, we all know what the end result can be!
2. No problem torquing one side only.
3. I don't remember, but it should be adressed in Waynes book and Bentley.

strictly · 05-07-2016, 10:53 AM

cool thanks for the reply. hmmm duely noted on the divilar, i certainly dont want to risk a popped stud. The threads do look dry from previous. And good to know that just building up and torquing the let side would be okay. I'd rather not distrub the right side, unless the unnamnious response was i should.

If it runs well, i drive it for a bit for the summer (my 2.4 is a little tired anyway), and tear it down and do it all right one day.

racing97 · 05-07-2016, 03:44 PM

Quote:

The reason i was thinking perhaps it has had a grind, as its not aggressive enough for a 3.5 on 46mm PMO's?

Call DR Cams or Dema Elgin you can't put enough on that small base circle for a engine that size.

Regards

strictly · 05-08-2016, 12:21 AM

Quote:

Originally Posted by racing97

Call DR Cams or Dema Elgin you can't put enough on that small base circle for a engine that size.

Regards

ah ha interesting, i have to read between the lines here, but the cams could be better (more appropriate grind) is what your saying, assuming they are stock solex, i will have to look into it.

strictly · 05-08-2016, 12:29 AM

p.s i still need help with question 3.

I am going to measure the cam timing on the right side, just for reference purposes. Will i get a correct reading with the hydralic tensioner still fitted? Its sat for years. I have the stomski mechanical tensioners. Once i have worked out the cam timing/grind. I obvuisly need to set up the left side. Should i redo the right side, or just leave alone? I guess that answer depends on what i measure vs what it should be

Trackrash · Trackrash's Garage

Is it single plug? What is the compression ratio? 35 deg is too much advance with a conventional ignition. The older cars with higher CR used 30 deg max advance. If it is twin plug even less.

Those cams? Are they three bearing or four bearing? What is the diameter of the bearings? What cam housings are you using? Is there a stamp on the end of the cam that would indicate they were reground?

Most recommend anti-seize on the head stud threads.

You can time your cams with the stock tensioner, I use a small clamp the make sure there is no slack in the chain.

KTL · 05-09-2016, 09:16 AM

Why not just get a replacement coil pack and run it the way it's already been set up? Especially since your TEC-3 ECU is already driving both the fuel and the ignition. You can get a new DFU unit from Clewett.com

The head nuts are supposed to be installed with copper paste on the threads and on the underside of the nut where it contacts the thick supporting washer. I agree that retorquing used dilavar studs can be risky. At least you have the best iteration of the dilavar studs with them being the 993 all-thread version.

strictly · 05-09-2016, 11:09 AM

Quote:

Originally Posted by Trackrash

Is it single plug? What is the compression ratio? 35 deg is too much advance with a conventional ignition. The older cars with higher CR used 30 deg max advance. If it is twin plug even less.

Those cams? Are they three bearing or four bearing? What is the diameter of the bearings? What cam housings are you using? Is there a stamp on the end of the cam that would indicate they were reground?

Most recommend anti-seize on the head stud threads.

You can time your cams with the stock tensioner, I use a small clamp the make sure there is no slack in the chain.

Gordon, thanks for the reply =)

It is single plug. CR I dont know, but its higher than a standard euro 3.2 im guessing so thats got to be close to 11. Ok noted about too much advance, glad i asked the question! thanks

Cams are 3 bearing. I'll check the diameter tomoor, and the cam housings part number, its definatly 901 something. I will check the part numbers tomorrow.

No stamp that I can see on the cam, that may in fact be standard solexes, im taking a worst case approach! I measured the intake and exhaust lobe length (i.e max lift) and found they are close to the specs for the solex cam. I then checked the cam timing, and its at 3.85mm, which is a little low. I am going to retry it tomorrow with a mechanical tensioner, just to see if the tensioner makes a difference to the measurement.

Its the first time ie done any cam timing, so taking it slow and checking everything

anti-sieze, ive noted that. Can i ask, is anti sieze the same as copper grease, or should i specifically buy the anti sieze?

strictly · 11:24 AM

Quote:

Originally Posted by KTL

Why not just get a replacement coil pack and run it the way it's already been set up? Especially since your TEC-3 ECU is already driving both the fuel and the ignition. You can get a new DFU unit from Clewett.com

The head nuts are supposed to be installed with copper paste on the threads and on the underside of the nut where it contacts the thick supporting washer. I agree that retorquing used dilavar studs can be risky. At least you have the best iteration of the dilavar studs with them being the 993 all-thread version.

Kevin,

thanks for that. Very helpfull. I am thinking about what you said, about going with a replacement tec-3 coil pack, and dfu. I had a good look for an ECU today (in the car), i couldn't find one. So i think i have the electromotive version that just controls the ignition. I took it apart to look at the circuit board, it looks okay but the connections are fire damaged so im not going to risk it. My intial reluctance to buying a direct replacement was was because its alien to me.

I know dizzys and CDi very well. My main idea was just to get the engine running first, by using my cdi and distributor from my 2.4T (of course its the wrong set up) but i was thinking it should at least run.

However i found out today, that the 3.2 has a different drive for the distributor, and therefore i would need to find a 3.2 dizzy AND another dizzy (as i need my 2.4T one for the 2.4!) and then i would have to recurve it (or lock out the advance and go MSD)

So ive come full circle to your idea of just replacing what is there. I am going to look at the cost. One issue could be im in europe, so duty/import (approx 30%) and shipping all pay their toll.

The wiring of the car is shocking. It looks like that is what caused the fire in the first place, so half my thinking was to revert to cdi/msd, which is simple and proven and do away with the whole bodged/rigged DME/motronic, or at least what looks to be left of it

Thanks for the response. Much Appreciated =)

KTL · 05-09-2016, 11:31 AM

Well if you can't find the TEC ECU, then you may be mistaken about what type of Electromotive you have? I didn't make the connection between your ignition and fuel until now, as I was not paying close enough attention. When I saw 3.2 to 3.5, that made me think Motronic fuel injection. But then you said the fire damaged one of the PMO triple carbs. So, duh, no fuel injection!

So my point is that you may not have the TEC style of system with a separate ECU and separate DFU coil pack unit. You may have the older style HPV or HPX which has the coil packs and ignition electronics all in one unit. Post a picture of your ignition and we can clear up that confusion?

We'll figure out the mystery engine you've got there. Just need to keep feeding us supporting information & pictures so we can identify what pieces you have.

strictly · 05-09-2016, 12:06 PM

We'll figure out the mystery engine you've got there. Just need to keep feeding us supporting information & pictures so we can identify what pieces you have.

lol, thanks kevin. I think it is the HPX (or was) with 4 knobs that you turn to set the ignition curve. I'll post some pics tomorrow. Pic heavy thread on its way. The proof quality wiring by the previous owner, will keep you awake at night, lol. At least im really good with electrics =)

Im in deep on this one :

3.5 (told 3.4) measured bores to be 100mm, Alien Ignition (for me), first time cam timing (hey i least i got all of the stomski tools), unknown engine condition (presumed good)

But its good. I wanted an engine that would stretch my knowledge. I enjoyed the learning process with the cams today

strictly · 05-09-2016, 12:07 PM

Quote:

We'll figure out the mystery engine you've got there. Just need to keep feeding us supporting information & pictures so we can identify what pieces you have

lol, thanks kevin. I think it is the HPX (or was) with 4 knobs that you turn to set the ignition curve. I'll post some pics tomorrow. Pic heavy thread on its way. The poor quality wiring by the previous owner, will keep you awake at night, lol. At least im really good with electrics =)

Im in deep on this one :

3.5 (told 3.4) measured bores to be 100mm, Alien Ignition (for me), first time cam timing (hey i least i got all of the stomski tools), unknown engine condition (presumed good)

But its good. I wanted an engine that would stretch my knowledge. I enjoyed the learning process with the cams today

strictly · 05-11-2016, 11:39 AM

Ok ive got some more info, i'll post some photos and make some comments at the end

Part number on cam housing

cam housing bearing bore - thats the spray bar version right?

this is the measurement of the cam shaft bearing in mm

bore measurement, im sure the stroke is stock 3.2 (but that is a guess lol)

this is all coming out

charming note from the person that did it

because if you were that good why didnt you use a terminal, and less duck tape on the rest

might have saved this! lucky i was an auto-electrician in a past life, and i can rewire the whole car back to factory spec with my eyes closed. Shame i dont know as much about engines lol

Flat6pac · 05-11-2016, 12:18 PM

It looks like you have inserts in the cam carrier to make the carriers usable with the smaller 3 bearing cam.
You can't go by the 901 casting number as 78 and 79 carried 4 bearing cams with the 901 casting before the factory began using the 930 casting numbers and went to 964 casting at least by 1988 model year.
Fire damage, not pretty.
Bruce

strictly · 05-11-2016, 12:32 PM

ah intresting. I had no idea you could fit inserts. Im learning something by the minute at the moment!

im trying to figure out my cams, but i think this will all make alot more sense when i measure/graph them which im going to do over the next couple of days.

At least im good with electrics =) gonna need it!

Flat6pac · 05-11-2016, 12:59 PM

I would consider a cut at the torsion bar from the proper group of years, stagger them and solder, shrink, then wrap.
Bruce

strictly · 05-11-2016, 01:07 PM

Quote:

Originally Posted by Flat6pac

I would consider a cut at the torsion bar from the proper group of years, stagger them and solder, shrink, then wrap.
Bruce

im thinking exactly the same, made a little easier as it was 3.2 motronic, but now on carbs, so no dme/motronic. Ive got a 73, which im actually going to "borrow" the cdi from, so i have an easy reference to wire it, just the alternator to convert to one wire. Going to do exactly as you say cut around the torsion area, and splice in a new section of loom, staggering it, with heatshrink and solder not tape lol, after i finish the block of course =)