Timing '69 1750 Spica

Jim, honest I don't try to make things difficult, but you said that I should rotate the pulley clockwise going on the basis (my term) that it has the later 70 degree BTDC I mark. Again, I have to say should that be the case one would then have to rotate the pulley 290 degrees to get to the I mark.

However...I have the earlier pulley whereas it is (as I said last night) 80 degrees ATDC to TDC.

Back to my original question, which 'cylinder' should the distributor's rotor be pointing at when the engine is at TDC before I rotate the crank pulley clockwise to the I mark?

I called a friend yesterday and by chance he'd just removed an identical engine/pulley from a Stepnose so he went through the drill while we were on the phone. He has no knowledge of this engine but in his case when the distributor was pointing at #1 cylinder and he rotated the engine clockwise to the I mark, the Spica marks lined up perfectly.

I'll add that in both Wes Ingram's Spica manual and my Alfetta's owner's manual - though termed differently - they're both saying to have the rotor pointing at #4 and then rotate the pulley CounterClockwise 70 degrees to the I mark (for the marks on the Spica to line up).

That said, I cannot imagine that the engine would even run if one still placed the rotor pointing at #4 and then rotate the pulley clockwise to the ATDC to the I mark to set the Spica. Theortically speaking if one had the old pulley (80 degrees ATDC) then changed to the later pulley, the Spica would then be squirting 150 degrees from where it had been before.

No offense, but for this pulley I'm thinking the #1 cylinder is the starting point, not #4.

I would be willing to try the 'new' way by making a 70 degree I mark BTDC but I wonder if the internal timing (what I refer to as the crankshaft) was specific for only the very early (gas) Spicas and must be timed ATDC.

Biba

Biba-
Spica timing is easily misunderstood. The engineers timed the 69s BADLY and that timing was changed to 70 degrees BTDC of the intake stroke during a subsequent recall. Timing the injection pump at other than 70 BTDC of the intake stroke will result in much poorer performance. The engine will run, but may have flat spots in the RPM range and be down on power.

The key operative word there is "intake stroke." The timing procedure of setting the engine on TDC (power stroke) of the #4 cylinder equates to the TDC (INTAKE stroke) of the #1 cylinder. So, we initially start with TDC on #4 power stroke, then rotate the pulley counterclockwise (as seen from the perspective of standing in front of the engine looking towards the rear of the car) to the "I" mark on the 1971-81 pulley (or modified mark on 69 pulleys). This sets the injection pump timing to 70 degrees BTDC of the #1 cylinder INTAKE stroke.

You can also use the #1 cylinder, but then you have to be sure that you're starting the procedure at TDC of the intake stroke, which is harder to see than TDC of the power stroke of the #4 cylinder (both of which are the exact same engine position).

Hope this helps clear up the confusion.

John, I truly appreciate what you are saying. A bit of the background on this car. It's a client's and ran pretty good when delivered to me but it was difficult to really tell since the clutch only 'took hold' at the very end of releasing the clutch pedal. I've not rebuilt the engine since the compression was virtually perfect in all four cylinders as was the oil pressure. It came with two different cams installed, both for Weber carbuereted engines. With client's permission I've switched them and retimed the cams. I also told him I'd check the Spica timing and change it if necessary. Meaning, he's going to be expecting a better running engine - as he should.

If I start deviating from the original Spica timing (whatever that is) I have to know absolutely for sure the Very First Spica (gas) pumps were not unique unto themselves and the recall was only the crank pulley and a 'different' way of timing the Spica pump. If no one really knows for sure, I feel I should time it as it was originally intended to be. I am loathe to experiment by trying different Spica timing methods. Right now the hood and radiator are not installed. I want to get it right the first time.

My ignorance: Please do not use the terms intake and power stroke. Just as in cam timing for me the starting point is with the valves both closed on #1, the cam lobes are pointing out, and the pulley is at TDC (and yes I've set this very carefully with a dial indicator - the engine came with no pointer on the water pump).

Should it be determined I should set the engine 70 degrees BTDC from TDC, which 70 degrees do I use? I've just figured out that Alfa's 70 degree I mark is a myth. I just very carefully went through the procedure with a loose pulley from a '75 Alfetta. The 70 degree mark is actually 62 degrees. The measurement around the pulley is 2 5/8" from TDC to the I mark. I have a '79 Spider engine sitting in my office. The distance from the TDC mark and the I mark is 'about' 3 1/16". Yes, the pulley's are the same diameter. By my very crude calculations (but bet I'm not that far off) this '70' degree mark is 72 degrees.

So now I ask again, which is the ideal 70 degree mark for the early '69 Spica?

I know I'm coming off as a smart ***, don't mean to be, but I'd really like to find the ideal setting for this situation based on empirical knowledge, not theoretical.

I'll add there are likely few of the earlier Spica/80 degree ATDC I mark pulleys still around - but for those who have them, knowing the correct way to set the pump could be very helpful. I suspect most even very knowledgeable Spica experts don't know the actual answer.

The Spica marks on the '69 are/were set at 'about' 50 degrees BTDC on #4.

Biba

I have a '69 and I am absolutely certain that the best timing is 70 degrees BTDC. I wasted years trying to time to the old system and it wasn't until I found this forum that I understood the factory error. As John intimated, the motor will run with the '69 timing but it will run much better with the '71 timing.

It is very interesting that the marks are not that accurate. I have never even thought about that. OTOH, several people on the forum and elsewhere preach the use of a degree wheel. That certainly makes sense in light of your revelation.

BTW, once timed, then what? Are you planning a full on assult on the SPICA? I ask because the more I get into the MFI, the more amazed I am at how well they perform. I just finished a rebuild of a 1750. It ran fine with a recently rebuilt Ingram pump but I spun a bearing so it was time to tear it down.

Since I had the motor out of the car and I have a hot engine stand, I took the opportunity to really work on setting up the SPICA. I have a fresh motor and a fresh SPICA pump (and a working TA) - if ever there was a time, it was now. Also, I was really fired up after hearing Wes Ingram talk at the national convention this past summer. He made the comment that as you go through the set up procedure the motor actually starts to run WORSE. It is not until you get to the final adjustment of the FCS (idle screw in the case of a '69) that everything comes together and the motor evens out. In the past I have "fiddled" with setting up a SPICA only to get discouraged because it would end up worse. In retrospect it was because I was doing things out of order and/or incompletely. There is no "close enough" in SPICAworld nor are there unnecessary steps. Every step is necessary as is the order.

So I was bound and determined to do it right. I went so far as to make , with the help of John Stewart, replica's of factory SPICA tools. All I can say is, if you have never experienced a well set up SPICA, you are in for a treat. I hit the starter and within one revolution it is idling right at 750 rpm. Power rolls on with no flat spots.

And lest one thinks that this is only possible with a fresh motor, I am here to say that I have also set up my '73 GTV's 2L that has never been opened up and it purrs! (BTW, I do have a Crane optical ignition which I highly recommend from a reliabilty standpoint.) My plan is to drive this car as deep into winter as I can. As long as there is no salt on the roads it will be on the roads. I really want to see what these motors can do in extreme conditions (ie Michigan). Thus far this motor performs consistently well in 100 degree weather down to the mid 30's. We'll see when we dip into the teens but I'm putting my money on the SPICA. I also have a spider with Webers which I love to drive but I won't even try to start when it gets even a little cold.

I've grown up believing that Alfa's are beautiful but temperamental cars. I am beginning to see that they are far from that.

Biba -
There was a formal recall by Alfa on the 69s to re-time the injection system. It was very specific about where to scribe the new "I" timing mark. I don't have the Alfa tech order document on my laptop right now. When I get home I can try and find it. I think you have one of those few cars that never got modified. The original factory 69 Spica Manual I have specifies 80 degrees ATDC of the induction stroke.

There was no physical change to the pump itself, only to the timing.

With regards to the Alfetta index marks, I'm at a loss to explain that, unless you're confusing the M mark for maximum ignition advance. All tech materials from Alfa specify that the proper timing is 70 deg BTDC of the intake stroke. I have no idea on the cams, but I do know that on the 2L engines, many people install 1750 cams or Euro carb cams for slightly better engine performance with no decrease in driveability. The standard 1750 cams on the 69 Spica engines should be good performers.

gprocket, while I really appreciate your trying to help, you've not grasped that the I mark on this particular pulley is on the opposite side (counterclockwise) from TDC. Therefore 'should' I use this original timing mark, Wes' 'how to' does not apply here. I also have both of his old and new manuals.

John, it certainly helps to know that there were no internal changes to the early version of the pump itself, just the recommendation to time the pump differently (you are sure of that aren't you?).

I assure you I know the difference from a M mark and an I mark. I will say that the marks on the 69's pulley are very faint but after finding the M mark I found the P and F marks and then went hunting for the I mark. When you have two pulleys of the same diameter and each of the I marks is placed differently than the other, they both (or neither) can't be at 70 degrees. I will say that possibly the belt's groove depth might be somewhat different which 'might' change things - though doubt it.

I can only assume that Alfa varied the 70 degrees I mark to walk the fine line between fuel mileage, HP, but mainly for emission's purposes.

My understanding is that Alfa panicked regarding being able to pass the then recent US' emissions and safety laws and went overboard. In another life we can discuss the absurdity of the dual brake boosters.

So to really muddy the waters, did Alfa undertake the recall for the crank pulleys because they weren't running well - OR - because their emissions weren't acceptable?

While I didn't rebuild this engine, I want to turn over a very nice running car to my client once the restoration is complete. 69's in CA no longer need to be tested for emissions.

I would appreciate knowing what (actual) 'degree' Alfa recommended for the revised I mark on the '69 crank pulley.

Biba

To repeat this Spider came with two Weber 'type' cams. Originally the 1750 Weber/Euro cam was on the exhaust side while an earlier 1600 Giulia Weber cam (set at around 116 degrees) was on the inlet side - which is why I switched them and set both at 104 degrees. I'm quite sure it will make a fairly significant difference in the running of this engine - if only I can find the optimum Spica timing.

Biba - I don't have a copy of the original Alfa Romeo December 5, 1969 Service Bulletin that instructed dealers to shift the injection pump timing, but here's a summary of it from Alfa Owner:

TECHNICAL NOTE, Alfa Owner , January 1970
A new Alfa Romeo Service bulletin, issued December 5, 1969, advises a major shift in fuel injection timing for U.S. 1750 cars. The change applies to models 105.51, 105.62, and 105.71.

The change basically involves rotating the fuel injection pump pulley relative to the crankshaft so that the timing mark on the pump pulley lines up with its index at 70° BTDC rather than 80° ATDC as before. The change can be done by dealers by filing off the old "I" notch on the crank pulley measuring 1 9/l6 inches forward (clockwise as seen from the front) from the "M" mark, and inscribing a new notch to be used when setting the injection pump pulley relative to the toothed drive belt. It may be necessary to re-adjust the idle bleed jets after changing the injection pump timing. After the modification, the fuel delivery adjustment screw can be backed off to lean out the mixture, with the final setting to be determined by road testing. Some cars have already been set up this way at the factory; they can be identified by a spot of yellow paint on the protective cover over the pump drive belt. The following chart is a guide to telling if your car has this modification:

Alfa mod'l Some after Chassis No. All after Chassis No.
105. 51 1.530.748 1 530 769
105,62 1.481 196 1.481 373
105.71 1 555.770 1.555.799

The effect of the modification is to advance injection timing, lowering exhaust emissions and improving "driveability" and fuel consumption, according to the Bulletin. This modification, if applicable, will be accepted under warranty for cars in stock with dealers as well as those already on the road.

Rich, did you work on this car? You're spot on regarding the cams. The exhaust cam originally was 10548 03200 01 and I might have been a bit confused regarding the (originally) inlet cam since it is a 10502 03200 01. I was looking in a slightly different spot and saw that 10502 03200 01(2) was for a Giulia Super. No doubt you have the same info since the (2) (which I hadn't checked) says that early versions ended in 0, not with a 1. So most likely the cam was an original Spica cam. As mentioned the cams have now been switched and set at 104 degrees.

John, Rich, I just went through the drill and after cleaning and painting both the Spica and crank pulley's I did the 13 teeth from the Spica timing marks after setting the TDC on the crank pulley and installed the belt. I was a bit disappointed that the 13th ended up somewhat to the left once the belt was on (what a pain).

Not being a trusting sole I then rotated the crank pulley one complete revolution then continued on to where the Spica's timing mark's lined up. Certainly not to a 1 degree in accuracy, but carefully done I came up with the I mark ending up at 76 degrees BTDC. Les does say that if the car has performance cams and pumps the timing can be advanced so the pulley would be rotated only eleven teeth.

Unless I'm terribly confused I'm guessing I now have it advanced with one less spline.

Comments? In any event, I really appreciate your sticking in here with me and for this doubting Thomas you both came up, in your own ways, with irrefutable evidence that this is how it should be done/set - and why.

Unless I hear otherwise, I'm going to file in a new I mark on the crank pulley where it now lines up with the Spica's marks.

Biba

Once again you're made an interesting observation. I also noticed that after using Wes' alternative timing that the the SPICA timing marks didn't quite line up. I was planning on looking at that further but have yet to have the chance. In the end I think I would stick with the original intent of the engineers and get the pump set to 70 degrees BTDC of the intake stroke. At this point it would be wise to use a degree wheel.

You are correct that pulling that toothed belt on and off is a royal pain. I use WD-40 but it is just not fun. Also I hope you have done what many have suggested and retire that the pulley cover. It serves no value and makes a difficult job that much harder.

As to the cams, Richard Jemison (Alfar7) recommends the following with a SPICA pump:

Intake: 10548 cam timed to 104-108 ATDC
Exhaust: 10502 cam timed to 104 BTDC

This amounts to moving the timing mark on the cam to just outside the timing mark on the cam cap. In other words, the inside edge of the cam mark would line up with the outside edge of the cap mark to give you 104 degrees. This would apply to both intake and exhaust. With a fresh SPICA (timed to the alternate method), a working TA, and cams timed above, my motor is everything I could hope for. The only other suggestion I might make is to add an electronic ignition. I use the Crane optical (about $100) and I think Pertronics is making a magnetic version now for our Marelli dizzies that is a little cheaper. You can also spend $400 + on a replacement but for street use these cheaper units are fine. I think the points and condenser become the weak link in the system as far as reliability goes and by going this route you will have a happy client for a long time...