engine build

[Davidm1600]

While I would tend to agree with pretty much that has been said here, and of course it all depends on precisely what you want, on one small matter I would disagree.   As nice as the classic 10548 cams are, according to Max Banks and plenty of other knowledgeable guys on the AlfaBB, they would all suggest that these cams at best should only be considered very mild. Having driven both standard 105 Alfas with and without these cams I am afraid I would concur.  They offer a little more torque but in truth that is about all, and certainly nothing to get too excited about.

If you are serious about increasing engine performance then there is a lot that can be done, including as suggested porting, polishing, bigger valves, race valve springs, mild to hot cams, 45 or 48 webers and extractors etc.   But then you can go a long way further, including hi compression pistons, lightweight and balanced engine/flywheel, and so on.  If you want a powerful, but aspirated Alfa engine, talk to Vin Sharp at Pace, but the more developed you go the bigger the $$$.   The other option is go a Twin Spark engine and develop this rather than a Nord engine.  

Again, check out websites such as Alfaholics as they get 190-200 BHP + out of their engines.  There is a lot of technical info out there if interested.

[alfagtv58]

Have to agree with Dividm1750.  There is soooo much more that you (actually Vin!) can get from the Nord.  But it costs $.  The old saying 'Speed costs money, how fast do you want to go?'.

My Alfetta with 2 litre was dyno'd at 115rwkw (155bhp @ rw).  And if you choose to go with Elf or some other sort of rocket fuel, you can get more.

Picture of the top of the pistons that can be shoe horned into the Nord below.

[Davidm1600]

They're pretty wicked looking pistons Phil and yes, my point exactly. 

A bit like the proverbial piece of string. The more you do, = more power (and we all know how great that is  ) but then up go the costs rapidly, which is fine for a race motor, but not necessarily for a purely road car.  Oh and then depending on how far you go, one needs to start looking at pretty much everything else, ie, brakes, suspension (front and rear), gearbox, diff, clutch etc etc.  Where do you stop. Goodluck anyway with the 2L engine warming.  Dave

[enzo1891]

ok first we never mentioned carby sizes, so yeah bigger carbys will require more of an open inlet but remember bigger is not always better you really need the horse power to run bigger carbys, now trumpets yeah i belive they are a waste of time but i never actually used them myself i am just going off from a my mechanic that tought me about alfas, and he said to me that they did a test at alfa city in peel st and used a alfa with a orignal air box and the same car converted with a air pods and the orignal air box had more response. and if you reaaly look at some of the old pictures of the old school race car yeah they run trumpets but they still used cool air box, think about this how does your alfa run on a stinkying hot day? 

[carjunky]

I had a 1984 Alfa GTV, they had 1048 cams the same as the 105 series and to get an extra 10hp you retarded the exhaust cam by 1 tooth . The exhaust camshaft timing used to be advanced to lower emmissions. Lorenzo from Alfa Australia told me in 1986, I did it and the difference was huge.

[Mat Francis]

I had a 1984 Alfa GTV, they had 1048 cams the same as the 105 series and to get an extra 10hp you retarded the exhaust cam by 1 tooth . The exhaust camshaft timing used to be advanced to lower emmissions. Lorenzo from Alfa Australia told me in 1986, I did it and the difference was huge.

I also heard something similar a while ago, never tried it as i didn't know if it was true, or if there would be any other adverse effects.

Anyone else ever done this?

[carjunky]

It is  true, I did it myself, if you have your Australian spec supplementary manual, a little white booklet and compare the camshaft timing to the euro spec car you can see the differences, I still have the Haynes manual from back then and wrote down the two different readings. The Australian spec car was exhaust valve open at 69 degrees 20' BBDC the  euro spec 63 degrees 54' BBDC and closed at 32 degrees 20' ATDC and the euro spec  41 degrees 20' ATDC. I definitely  remember retarding the exhaust camshaft 1 tooth. It was a long time ago but I have checked the book where I wrote down the figures, maybe someone else remembers but it really did make a big difference especially to the torque and you really felt it in 2nd gear. Lorenzo Montressor was the guys name, he was  the chief mechanic at Alfa Australia in Sydney.

[Mat Francis]

Excellent information. I'll add it to my list of things to do to the Alfetta during it's upcoming overhaul. Thanks

[Craig C]

Have to agree with Dividm1750.  There is soooo much more that you (actually Vin!) can get from the Nord.  But it costs $.  The old saying 'Speed costs money, how fast do you want to go?'.

My Alfetta with 2 litre was dyno'd at 115rwkw (155bhp @ rw).  And if you choose to go with Elf or some other sort of rocket fuel, you can get more.

Picture of the top of the pistons that can be shoe horned into the Nord below.

Phil what did you do to get your 115kw and in what order, ie what provides the biggest improvement first?

[alfagtv58]

Hi Craig,

First of all, good to see you got yourself an Alfetta as well as the spider!  What are the plans for it?

To answer your question, I didn't do all that progressively.  It was all sent off to Vin (PACE) & Hugh (Monza Motors) at once with the request of 'one with the lot, extra fries please'.  It should also be noted that you couldn't really drive it on the road, well maybe you could....just, but it would drive you mad.  Basically - high comp pistons, lots of head work, cams, extractors, carbies are 48's (with the carby extensions).....and lots of love screwing it together!  Vin would be the best guy to ask what to do in what order, I rekon some of these mods would not get the full benefit unless the other steps were taken also (for example, you wouldnt put 48's on unless you had the head flowing better)......but, check with Vin, he's the man!

[Colin Byrne]

I think you'll find that runner lengths and bell mouth design can have a massive effect on power that an engine can produce, there is a reason why race teams spend considerable money and time with flow analysis software and flow bench testing to optimise the designs, sure you are going to get limited improvement  if you just through any old trumpet on any old engine, but a blanket statement that

trumpets yeah i belive they are a waste of time

Is just not correct

[Craig C]

Hi Craig,

First of all, good to see you got yourself an Alfetta as well as the spider!  What are the plans for it?

Well at the moment it doesn't go and has a bit of rust but so far looks like a good project car to get started.  First priority is to get it trackworthy, then later roadworthy and gradually improve it with the track in mind.

It's a lot of fun already but i'm looking forward to getting it mobile.

[Paul Gulliver]

Craig,

Great to see your purchased an Alfetta and want to get it to the track. This is worthy of another thread , so you don't get whacked for hi jacking this one. There are plenty of people in the club that have been around the block on this kind of development and i'm sure they will share this wealth of knowledge.

As Phil said  110kw rw from an old Nord engine is certainly possible but very expensive and i would doubt it would be streetable. Also i wouldn't be attempting anthing like that on standard Alfetta brakes & suspension.

Don't underestimate how much fun you can legally have in an old Alfetta for 2-3 hours on a Sunday morning in the Yarra Valley or in  the hills in South West Gippsland. so be specific about your initail breif (ie do you want to drive it to the track or trail it)

Here's some follow up reading from Alfa BB .

http://www.alfabb.com/bb/forums/alfetta-gtv6-1975-1986/139711-ten-77-alfetta-gt-upgrade-suggestions-wanted.html


Hope you can get that new thread up. ( Perhaps something along the lines of 116 2 litre budget racer / weekend club car) 

Cheers

Gully