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Discussion Starter #1 (Edited)
OK some of you might know I was having low oil pressure problems with the Spider, thought it was the oil pump after a check up at a main dealer. After my Indy garage took the sump off it turns out there pretty bullet proof and it ended up being worn main bearing shells and scored crank end. Horror :cry: previous owner ran it low on oil and the damaged was done :mad:

So, engine out and the blocks being freshened up with satin black paint (hammerite) the cranks being reground, pistons, con rods and fly wheel lightened and balanced, balance shaft removed.

I have a rebuilt head ready to be fitted.
New clutch will be fitted at the same time.

Is there any good advice or info any1 would like to give me?

Cheers Andy
 

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Sorry to hear that bud, really am. Look at it this way though mate, you are doing such a great job looking after her that an engine overhaul is a logical step!

You will have a fantastic looking / running car that is a credit to you. Hoping to see the results for myself sometime soon and we can swap Alfa battle stories over a beer :thumbs:
 

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Discussion Starter #6
I won't be doing the work myself T, but I will get pics of the progress to add to the portfolio :thumbs:
 

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Discussion Starter #7 (Edited)
Progress Report

Ok so the engines out, poor Spider waiting patiently for the Rebuilt lump to be fitted!

Parts got so far and work done......

New Valeo clutch
Rebuilt head (cams,water pump and thermostat fitted)
Head gasket set
Powder coated new part
Painted engine mount
Painted Air compressor bracket

Still waiting for the Oil pump to be delivered from Turin (Italy)

The blocks still at the machinists, hopfully the pump will arrive mid next week and the build can move forwards :thumbs:

Monday eve I'll be picking up the gear box to clean (paint if needed)
 

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Just think how great it will run/look when it's all back together :thumbs:
 

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Looking fantastic - great job :)

Only thing I'd say is - I'd want to keep the balance shafts - why compromise the refinement of the engine for no real benefit?

-Alex
 

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Discussion Starter #11
I would have to agree with you Alex,
if I wasn't lightening and balancing the pistons and con rods! Fly wheel is getting a bit taken off the back too so I will have a well balanced and refined engine after this work is done.

Oil pressure will be improved once the balance shaft is removed (never a bad thing) :thumbs:

The balance shaft does take power from the crank, not alot but I would imagine its like having the air con on (slight lack in power)

They don't use balance shafts in TS race engines and as this is a weekend toy I'm sure it will be ok.

I'll let you know what its like once run in :D
 

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throwing some proper money at yours buddy , picking up a 2nd hand engine for my non runner later ! been waiting too long to find a decent unit at the right money but good things come to those who wait !
 

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Discussion Starter #13
There are some good deals out there at the minute!

I always said to myself if there's a problem with the engine I'd have it rebuilt. I haven't cut corners or saved money with this car as it always was gonna be a keeper!
Turns out a local guy doing the work on the bottom end does this sort of thing for his bread and butter.

I do like the idea of an engine swap tho! (16v turbo fiat coupe ) For another project.........

Best of luck with your 1 mate I bet you've missed driving her.
 

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I would have to agree with you Alex,
if I wasn't lightening and balancing the pistons and con rods! Fly wheel is getting a bit taken off the back too so I will have a well balanced and refined engine after this work is done.

Oil pressure will be improved once the balance shaft is removed (never a bad thing) :thumbs:

The balance shaft does take power from the crank, not alot but I would imagine its like having the air con on (slight lack in power)

They don't use balance shafts in TS race engines and as this is a weekend toy I'm sure it will be ok.

I'll let you know what its like once run in :D
Cool, sounds exciting :)
Maybe you should spring for some Colombo and Bariani cams, I can't remember which place has them - Alfaworkshop or EB Spares? Rather expensive, unfortunately... but it would be great to see how a race engine can be made on a reasonable budget (and to learn how it goes on the road...) Would transform the character of the car too and bring out some of that highly-strung magic for which Alfas were once known.

-Alex
 

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Can I just ask about the flywheel job? I didn't think you could mimic the balance shafts using the crank/flywheel because the vibration is 2nd order (twice per revoltion). Otherwise Alfa would have done it.

So whats this about taking a chunk out of it and what is the logic? Cheers

Edit: sorry, read your post again... You are just making the flywheel thinner I think
 

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Can I just ask about the flywheel job? I didn't think you could mimic the balance shafts using the crank/flywheel because the vibration is 2nd order (twice per revoltion). Otherwise Alfa would have done it.

So whats this about taking a chunk out of it and what is the logic? Cheers

Edit: sorry, read your post again... You are just making the flywheel thinner I think
I was thinking that too. I think the main benefit of the balance shafts - for me anyway! - is to reduce the inevitable shake at low engine speeds caused by that 2nd order vibration (the Bosch Automotive Handbook does a good job of explaining this). FIAT/Alfa had no problems making engines that ran to high revs without destroying themselves and I don't think the balance shafts are for that purpose, and therefore removing them from race engines makes sense. The smoothness at high revs depends on balancing/weight matching the main parts, as Andy is doing - should run great :)

But when sitting at traffic lights, I like not having the steering wheel shake. I believe that low-speed smoothness depends mainly on how many cylinders there are and how big the explosions are, I don't think the balancing (crank, flywheel, etc.) will affect this but I reckon the balance shafts take out some of the thump. Will be interesting to learn from Andy's experience whether that's actually the case. Two litres was always the reasonable limit for a four-cylinder engine to be acceptably smooth; I think it was Mitsubishi and Porsche who last exceeded this (2.4 and 3.0 litres) and that's when they applied the balance shafts which, I think, were originally a Rolls-Royce patent - Mitsubishi snapped it up when it expired in the 80s? EDIT: no, it was Lanchester, sorry... I don't think many manufacturers have used balance shafts on 2 litre engines - FIAT introduced them for the 2L four in the late-80s Lancia Thema. Must go and have a check on Wikipedia, probably some American econo-luxo-barges had them? ;)

I feel that the 2.0TS is a long-stroke motor (undersquare, stroke larger than bore) compared to old FIAT/Alfa standards. The smaller four-pots in the 1970s/80s were always oversquare, which facilitates smooth high-speed running but reduces torque at low speeds, making it smoother but also less torquey, and torque is what you need for economy/low emissions. Therefore since the '90s the trend seems to have gone back the other way, to the undersquare proportions used before the '70s (excepting Honda, of course). So without the balance shafts I would have thought the TS would feel quite rugged at idle, like a '70s Lotus or tuned Ford of that era (and I mean that in the nicest possible way :)) Who cares if it's a race engine - just turn the idle up a bit...

Beats me why four-cylinder diesels don't have balance shafts - I would expect it would help them too... Of course, the FIAT/Alfa solution is to use 5 cylinders...

Useful article here: http://www.autozine.org/technical_school/engine/smooth2.htm

-Alex
 

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Discussion Starter #17 (Edited)
Maybe you should spring for some Colombo and Bariani cams
I've looked into this but its difficult to time up the belt with C&B cams. (no cam locks) to get full benefit from having the C&B cam you would also need ITB (individual throttle bodies) Pic added. You looking around £2,000 for this work. (200bhp) I'd rather get a V6 or start that turbo project I have waiting in the wind ;)


Can I just ask about the flywheel job?

Just shaving a bit off the back to lighten and balance the fly wheel.
Its the pistons and con rods moving up and down that will unsettle the engine, with this being balanced no need for the balance shaft!

P.S.....I'm no expert but this is my under standing :)
 

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I've looked into this but its difficult to time up the belt with C&B cams. (no cam locks) to get full benefit from having the C&B cam you would also need ITB (individual throttle bodies) Pic added. You looking around £2,000 for this work. (220bhp) I'd rather get a V6 or start that turbo project I have waiting in the wind ;)
Ah, I see! Thanks for clearing that up for me... Racing ain't cheap is it... :cool:

Just shaving a bit off the back to lighten and balance the fly wheel.
Its the pistons and con rods moving up and down that will unsettle the engine, with this being balanced no need for the balance shaft!

P.S.....I'm no expert but this is my under standing :)
Yes, I believe it's never quite possible for a 4-cylinder to be truly balanced (regardless of how balanced the components are), but it is probably not going to be an issue, just like it normally isn't an issue for smaller engines, and I look forward to your report. The Wikipedia article mentioned 15hp as the power loss. 15hp! I think I'd be taking out my balance shafts if that's the case (I doubt it's that much?)

-Alex
 

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Discussion Starter #19
Thats interesting link Alex thanks for posting!

I really think this won't be a problem with my engine because of this reason...

I had the belts done last year by a local guy who wasn't an Alfa specialist and he put the balance shaft belt on 1 tooth out! from what I've heard this is worse then removing the belt altogether. The car idled fine but had exhaust vibration at high revs, Once the belt was timed up correctly the problem solved.

There have been occasions where guys have just cut the balance belt and experienced no difference.
I've spoke to Gus at Alfatune and Adie at AHM Motor Sport and they both say it will be fine :thumbs:
 

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I took my belt off and it felt a bit more rough through the controls but not really much difference. I forgot to check if the belt was installed correctly before. Would like to know if the balance belt improves efficiency, as these designers really did anything and everything to squeeze another mpg out.

Tempted to put my belt back on and do some mpg trials.

Btw Alex, I have a massive crush on you for using the term "undersquare" and referencing the Bosch handbook!
 
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