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Richard Jemison
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Discussion Starter #1
As I am finishing up the build of my Montreal engine, (some of which I have posted on the thread relating to my Spider hardtop "coupe" (Alfaghia)):
http://www.alfabb.com/bb/forums/spider-1966-up/74007-spider-improvement-effort.html

I thought I would cover some of the assembly and modifications I made toward improving the engines performance relative to improved torque and drivability, not just HP. As well as cleaning up appearance issues as the magnesium parts are quick to corrode and get ugly.

Although a low mile motor, it has been stored for many years and had made it`s way to Canada from the collection of an Alfisti in Atlanta, before I purchased it.
It was a typical core motor with the common water pump issues and rusty sleeves from storage. Still I think it was worth the $7,000.00 plus that I had in it by the time I had it shipped to Florida from Vancouver Canada. I guess it has to be viewed in one`s perspective, as my wife would never agree. But then she`s happily ignorant of what I spend on car "stuff". I didn`t learn a lot from my first 5 ex-wives, but I picked up the basics!:rolleyes:

Below are pics of the engine as purchased in Canada. It had no distributor, Air box cover which entailed tracking down and buying lots of parts and building a modern distributor to work with the engine triggering a Crane msd ignition unit.
I`ll continue with subsequent build info as time allows. Typing on the computer does not get shop projects completed.
 

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Richard Jemison
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Discussion Starter #2 (Edited)
Engine disasembled

Below are pics of the engine disasembled, (what a complex piece!) for cleaning and determining what is going to be replaced.
Right off it`s obvious it needs pistons, liners, complete water pump kit, gastets etc.
Luckily the internals are good and the crank is perfect, as are the crome-moly rods, abd both oil pumps.
The pistons I ordered are much lighter than stock, and I had them coated with anti wear coating on the skirts.
All of the internal parts not available here in the states I ordered from Joe Cabb at Centerline. It`s nice to have a supplier that you can call and depend on to track down parts in Europe rather than do the lengthy search personally. Besides he has the contacts to find no longer available parts for these motors. He came up with the WP kit, bearings, chain guides etc. with no issues.
The internal drive for the waterpump is a weak link and re-machining the case for heavy duty bearings had to happen. Almost worth converting to an electric waterpump to eliminate any future issues. But electrical things being what they are, I really think anything flowing through a solid is the work of the devil, and will leave poor design as is and improve on it....:rolleyes:
The heads are typical old school with cylindrical thick valve seats and constricted bowls. As this is no race motor I decided to only open the seats and re-shape the valves for better flow and enlarge the bowl to port for better flow. Opening the intake seat 2 mm and the exhaust 3mm at the valve seat gave a significant increase in early (low valve lift) flow and good improvement in higher lifts on the flow bench. (there is more pics on the other thread about the head work including before/after pics)
The cams I designed and had built are designed for improved torque and HP across the engines RPM band. Lower early duration to reduce overlap which bleeds off torque and more "open" valve duration improves bnoth torque and HP without the losses in low RPM drivability.
The cams are 1mm more lift which is about all the splash shields will allow without removing them from the cam bearing caps. More on cams and cam timing changes later...
The crank was lightly polished and throughly cleaned. Clearance with the new bearings was .0015 mains and .0014 rods. With the 4140 rods the engine is easily good for 9000 RPM plus with the light pistons.
 

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Richard Jemison
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Discussion Starter #3
Internal assembly

Below are pics of the internals being assembled.
I decided even though this is a dry sump engine it should have a windage tray to resolve oil spinning around with the crankshaft. Built one from 7075 aircraft grade aluminum (stiff but unweldable) to scrape and return oil to the pick-up in the pan.
The oil pan was one of the items I had powder coated to resolve the magnesium corrosion issues.
 

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Richard Jemison
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Discussion Starter #4 (Edited)
Lightening Clutch

While I was building parts I decided the flywheel, although larger & lighter than typical Alfa stuff, could use some lightening and cut about 6 pounds from it. While at it I built a solid aluminum center RJR clutch disk to lighten the inertia that the syncros have to deal with. Flywheel was balanced to resolve imbalance caused by machining what was a "typical" casting that was not fully machined and balanced "as was" by the suppliers.

FYI, the Montreal and Alfa Sei clutch disk are (in stock form) idential to 9 inch small GM units. Same spline and diameter(1 inch 14 sp[line). Easy to find, but still not light with the "torque spring" steel centers.

If someones wants a excellent used one I have one I will not be using)

I purchased a ZF gearbox that was rebuilt by ZF of North America, and shorteded the shift tower location by 6 inches so it wouldn`t be so close to the driver. Pics below...
Pics of flywheel are below:
 

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Richard Jemison
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Discussion Starter #5
Powder coated parts

I had the Cam covers powdercoated along with the Oil pan and assorted brackets and bolts, in a bright silver.
The headers are ceramic coated after welding a bung in each to use a pair of broadband O2 sensors for a pair of air fuel gauges.
 

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Richard Jemison
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Discussion Starter #6 (Edited)
Distributor for Montreal

I didn`t want to use a points type distributor so I found a Mercedes 250/450 V8 Bosch distributor and machined drive parts to fit it to the Montreal drive assembly that is cam driven.
Below are pics of it as started and finished...more on the other thread...
 

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Nice work

Beautiful! I wish I had your skill. Obviously you are not going to install this in a Montreal. Tell us more. Sorry to make you take up worthwhile time typing instead of working on your car. Were there any other pieces available in Vancouver from the guy who sold you the motor? I am close enough to go there and see if there might be some usable parts I need. Jay in Seattle.
 

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Richard Jemison
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Discussion Starter #8 (Edited)
Head / Cam work

Jay, the only Montreal parts he had was the engine, originally destined for a pre-war racecar replica which instead got a 6c 2600 engine to keep it narrow.

The Montreal engine, is a complicated piece with all the chain driven pumps (2 oil and water) but different from other Alfa`s, the camshafts are hollow castings in which oil is fed only to the front cam journal, and the 4 rearward cam journals on each cam are oiled internally through the cam. Each cam is a different casting so it`s easy to see why there are no aftermarket cams floating around.

Being better versed than most in the cam builders art, I could never be satisfied with the old lobe design used by Alfa on everything before the latest Twin Spark renditions.
Since the best cam building process ( our extreme hard weld overlays ), would likely cause warping of the tubular shafts, and not being receptive to trying to find replacements, I chose a lobe profile that could be carefully reground into the existing lobes without a serious reduction in the cams base circle. Another factor was the limited space in the heads for higher lift lobes. The cam lobes chosen give a full 1mm + more lift, and substantial duration increases without the increades in overlap that kills lower RPM torque and power.
The profile of the factory Montreal cams are below, as duration at actual valve lift, between the original cams and the RJR260e profiles used for these cams.

Cam timing is similar to other Alfa 4 cylinder production cams with the factory cams placed at a very close Lobe Separation Angle (102 degrees, both LCs are 102). With the new cam designs I set the Cams at 103 degree lobe centers on the intake side, and 108 degrees exhaust, to bias performance back towards mid range, since the cam designs will improve upper RPM in any event, due to more open valve duration an enhanced lifts over the factory design. This isn`t a race motor so I want a wide torque band, without needing to rev the engine out of the car!
Here`s the cam data:

Montreal 2600 V8 cam lobes RJR206e Montreal Cams
Degrees of duration at actual valve lift with lash at correct settings
.001 276 280
.010 255̊ 256
.020 234°̊ 251
.030 228°̊ 247
.100 186°̊ 213
.150 166°̊ 196
.200 138°̊ 161
.300 81°̊ 122
.350 33°̊ 78
.356 valve lift(actual) (9mm) .394 actual valve lift(10mm)

10555.03200.02 right intake
10555.03200.03 left intake
10555.03201.02 left exhaust
10664.03201.02 right exhaust

Pics show cams in head in proper position at TDC on cyl.s 1 and 5

The Spica Throttle bodies have been cleaned and were ready to instal, but I have decided to increase the internal dimensions, by boring and replacing the 35mm butterflies with either 38mm ones from a 1750 Spica unit, or 40mm ones from the 2 liter Spica TBs that I have removed when doing the 44mm TBs in the past. The Montreal TBs are smaller and I`m concerned with thin walls if bored to 40mm. We`ll see... below is a pic of a RJR 44mm TB with the original 40mm Spica butterfly laying in it.
 

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Some awesome work there Richard, thanks for sharing so much information!
It's fantastic to see inside the Montreal engine :D
 

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Hi Richard. Nice work.

I bored my Montreals ITB to 38mm but had to weld up several places where it broke through the wall.

I've since replaced these with custom made 40mm ITB's with even more increased flow required for my 3lt engine. On the my 2.6 I use 40mm ram pipes tappered down to the 35mm std butterfly which is working well. A 25 degree angled adapter plate for the makes in the inlet track straight as well.

I see for your exhaust headers you have kept the standard flange right at the very early days I put a new one to open up the ID which improved the top end. But now run a 4-2-1 matched length system after numerous trials to get this right. The exhaust changes I made on the 2.6 engine provided the most hp and torque gains overall.

Did the engine come with the extra aircon roller bearing on front of the crank? If not it's worth getting one as it really helps to stop crank wipping as it has such a long snout on the bugger and smooths out the engine a little at high rpm.

Regards
Phil.
 

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Very nice work Rich....seeing a project like this come to fruition really makes me green with envy. If you don't mind my asking.....In the right hand top photo something looks odd....does the camshaft drive chain not run square to the cam centrelines? The intake cam sprocket seems to be further forward than the exhaust cam sprocket...why is that?
 

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Richard Jemison
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Discussion Starter #12
Continuing saga....

[Did the engine come with the extra aircon roller bearing on front of the crank? If not it's worth getting one as it really helps to stop crank wipping as it has such a long snout on the bugger and smooths out the engine a little at high rpm.

/QUOTE]
No, and I recall you mentioned that last year when I was chasing parts... Got a pic of it, as I havent thought about it but if it will improve reliability, I will find a way to do it. Will the oilpan/heads/front cocer have to be removed???

I havent touched the motor in a while, as I went to pick up the chassis from the painter.
 

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Yep I can give you some pictures I'll post up tonight for you. The engine can have tendency to run 1 and 5 bigends and the front main bearing when pushed hard for extended duration and as such the factory used the extra bearing on all race prepared engines.

It attaches behind the front pulley onto the front timing chest (those 3 bolts you see) and the bearing replaces the spacer you have fitted between the pulley and timing gear sprocket. So a simple post build fix with no modification required and uses the same front seal as well.

P.S. The cam cover "nuts" you're using aren't the standard ones.. are they alloy? I'm after some alloy ones to save more grams if I can get them.


Phil.
 

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Hi Richard. A picture of the bearing housing... it's simple enough, and would not be difficult to replicate if you're unable to source one. I can provide the a SKF bearing part number as well, just need to find the invoice.

Regards
Phil.
 

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Sorry to bother you again Rich. Are you going to still use the SPICA system or are you converting to EFI?

And the ZF gearbox you have pictured... Was that from an Alfa 6? As the completed tail shaft housing and mounting flange is quite different from a Montreal one?

Phil.
 

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Richard Jemison
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Discussion Starter #16 (Edited)
engine continued

Phil, the gearbox is one that I bought out of the ZF re-work facility, it was a unit designed for the Masserati. The rear drive coupler is for a u-joint rather than rubber giubo. I prefer a single piece driveshaft with a splined sliding coupler, rather than a multipiece unit as Alfa uses. The unit bolts up with no mods to the Montreal bellhousing, and for clutch release I`m using a Quartermaster internal hydraulic release bearing.
I shortened the shift housing about 8 inches along with the 3 shift rods internal to it.

I still have one of my modified 115 series transmissions with ultra close gears (2.0 1st / 1.59/ 1.25/ 1.0 and .86 fifth.) and still consifering using it in the "Alfaghia" Coupe:rolleyes:

My engine did not have the carrier for the additional roller bearing on the crank, and since this motor isn`t a race engine I`m not going to modfy it now. Since the only pull on the crank pulley is the alternator, and I`ve modified a 115 Amp Bosch unit from a 164 application driven by a large 5.5 inch aluminum pulley to reduce its RPM and residual drag.

I`ve been through lots of mental anguish over FI, deciding I will initially run the engine in the test stand using the Spica FI as it seems to be in good condition. I`ve even considered using a 1750 control unit in it if it seems too lean. However I favor Megasquirt and will resort to it, using Hilborn screw-in EFI injectors if the Spica isn`t capable or is troublesome. Have had offers to sell it but have held on to it so far... The engine must drive and perform correctly with no agravations or the Spica will be sat on a shelf.

The sparkplugs I again decided to use are Autolite XP3924s. A shorter extended tip, with fine wire electrode in iridium along with a pointed iridium ground electrode. Thes plugs will fire when other designs would foul out from fuel wetness (Spica?:rolleyes:) or oil fouling. They also require less energy to fire. Maybe you can see the electrode design in the pics.

Still debating TB mods....
 

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Looks good Richard.

I run the Champion C57CX race plugs (Stock number 295) which have a cut back ground to expose the electrode more. These plugs work real well and with the MSD HVC 6600 ignition system I run. Never have an issue with fouling and always an easy start as long as we have plenty of battery juice as the ignition system had a big draw.

The load on the crank at the front isn't really from the alternator but from the asymmetric load on from the timing chains and harmonic balancer. We measured some run-out at high rpm from the outer surface of the balancer hence the reason to retro fit the extra bearing.

Another question for you... Did you do any other head work other than the camshafts like bigger valves or porting?


Phil.
 

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Is that a Lamborghini Muira nose I see by the tyres in the background?

Pete
 

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Richard Jemison
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Discussion Starter #19 (Edited)
Questions....

Is that a Lamborghini Muira nose I see by the tyres in the background?
No, it`s the body that is going on the tube frame, 2 seat GTR (on my website) which has finally gotten to the point of being worked on again. Frame is being modified to take much larger engine than the 3.0 12V it was built around. May get the Montreal. The coupe might get a 2100 cc Nord that has been laying in pieces for a while.

I run the Champion C57CX race plugs (Stock number 295) which have a cut back ground to expose the electrode more. These plugs work real well and with the MSD HVC 6600 ignition system I run. Never have an issue with fouling and always an easy start as long as we have plenty of battery juice as the ignition system had a big draw.

The load on the crank at the front isn't really from the alternator but from the asymmetric load on from the timing chains and harmonic balancer. We measured some run-out at high rpm from the outer surface of the balancer hence the reason to retro fit the extra bearing.

Another question for you... Did you do any other head work other than the camshafts like bigger valves or porting?
The plugs are not a race design. I use the Bosch "dome" surface gap plugs on all the race motors. (see pic) There are Champion C57C and C59c as well as the Bosch plugs used for various applications.

The Montreal heads were modified by opening up the seats considerably, using a 75degree cutter as can be seen on the other thread. The valves (std) were reshaped and the seat which is at the very margin of the valves, is only .040 which gives better contact and seal, and opens up flow since seat is cut totally away internally. (Three angle seats only reduce flow volumn.)

Took 20 Spica 40mm butterflys and machined them to 38.4mm. Stacked them excentrically (8 degrees) so when machined they will now seat correctly in a 38mm bore at 172 degrees. Will bore the Montreal TBs next week as leaving tomorrow for the races and relaxing for a week.
The TBs will match the 38 mm intake ports on the head. The increase in butterfly size from 35mm to 38 will be about all the motor needs.
 

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Hi Richard. A picture of the bearing housing... it's simple enough, and would not be difficult to replicate if you're unable to source one. I can provide the a SKF bearing part number as well, just need to find the invoice.

Regards
Phil.
Hi Phil

You have my curiosity with regards the extra bearing on the nose of the crank.
I am looking at putting A/C in my project and I didnd realise it was such a simple mod.
I assume that the extra bearing is only narrow and the seal is the original one?

Graeme
 
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