Search found 25 matches
- Fri Aug 10, 2007 4:33 pm
- Forum: Engine
- Topic: Piston valve contact
- Replies: 6
- Views: 5721
Piston valve contact
x-rad, When a valve comes in contact with a piston the valve usually bends. But thats not all. To bend the valve does take some force which is easy for the crank to turn as the crank reaches TDC and the conrod straghtens. The valve comes in contact on the side of the piston with great pressure tryin...
- Tue Jun 19, 2007 1:04 am
- Forum: Engine
- Topic: knocking sound caused by loose valve guides
- Replies: 14
- Views: 8475
- Sat May 19, 2007 5:41 pm
- Forum: Engine
- Topic: 2.0 4cyl max liner bore
- Replies: 16
- Views: 13397
2.0 4 cylinder max liner bore
Just an update on increasing bore and stroke. I have recently spoken to a couple of alfa engine builders that have bored the stock liner out to 86 mm and have not any problems. They both said it requires boring and honing the sleeves in the block with a deck plate. I still prefer a dutile liner or e...
- Mon Feb 26, 2007 2:12 am
- Forum: Performance
- Topic: valve spring retainer clearance
- Replies: 5
- Views: 4739
Thanks everyone for the suggestions. x-rad I have found the Alfa OEM black seals with spring are shorter again at 9.3mm high, a gain of another 0.2mm. Also I will machine another 0.6mm from the bottom of the spring retainers which will give me 1.3mm clearance. TS_turbo Unfortunantly I cannot move th...
- Thu Feb 22, 2007 11:18 pm
- Forum: Race Cars and Track preparation
- Topic: Twin Spark Engines
- Replies: 341
- Views: 205318
Twin Spark Engines
Jim, I hope you realise that the asian rods do not come with the cap screw bolts. You have to supply them youself. You can get these for about US $15-$20 a pair per rod from various American parts supplies. Be carefull on your selection of bolts as I contacted ARP to get the correct bolt. You requir...
- Wed Feb 21, 2007 1:24 am
- Forum: Performance
- Topic: valve spring retainer clearance
- Replies: 5
- Views: 4739
valve spring retainer clearance
I am currently assembling my twin spark head with custom valves, custom guides, performance springs, and 11.6 mm lift cams. Before my final assembly I have checked the spring retainer to valve guide clearance at 11.6mm valve lift. The exhaust retainer to guide clearance is 2.5mm (no valve seals) OK....
- Mon Feb 19, 2007 6:41 pm
- Forum: Engine
- Topic: Anybody ever broke a Nord by over-revving?
- Replies: 35
- Views: 19795
Anybody ever broke a Nord by over-revving?
If you want to see a bent Alfa Nord rod have a look at Mike Valant's web site. His site is very interesting.
http://engr.smu.edu/rcam/cpm3v/2lrebuild/2lrebuild5.htm
Zamani, these could be what your rods look like
http://engr.smu.edu/rcam/cpm3v/2lrebuild/2lrebuild5.htm
Zamani, these could be what your rods look like
- Sun Feb 18, 2007 2:48 pm
- Forum: Engine
- Topic: Anybody ever broke a Nord by over-revving?
- Replies: 35
- Views: 19795
Anybody ever broke a Nord by over-revving?
Although the Alfa Nord engine is very sturdy in construction its limitations are the rods. Although they look robust they will fail from fatigue when taken often to high revs. I hear a lot of people saying I rev my engine to 8,000 RPM all the time no problems! But how accurate is the tachometer :?: ...
- Wed Feb 14, 2007 2:19 pm
- Forum: Engine
- Topic: cylinder sleeve installation
- Replies: 10
- Views: 7726
cylinder sleeve installation
x-rad, you are correct. The cylinders do move about in microscopic amounts, probably vibrate is a better term. This is why some engines have lost there cylinder protrusion above the block deck. (a common problem with diesel engines). After a while sludge and corrosion locks the cylinder spigot into ...
- Mon Jan 29, 2007 2:39 pm
- Forum: Engine
- Topic: cylinder sleeve installation
- Replies: 10
- Views: 7726
Thanks Brian16 and x-rad for your comments. I recently have asked the same question to a alfa race engine builder and he confirmed it is a good idea to bond the cylinders in to the block as it reduces stress on the head gasket. The engine builder said that bonding the cylinder spigots into the block...
- Tue Jan 16, 2007 4:30 am
- Forum: Engine
- Topic: cylinder sleeve installation
- Replies: 10
- Views: 7726
cylinder sleeve installation
I are just about ready to install my new cylinder sleeves into my Nord block. The factory correct method is to install the sleeves with a new "o" rings that is lubricated with a smear of silicon grease. Some people like to smear silicon sealant thinking that it would guarantee against any ...
- Fri Nov 10, 2006 5:38 pm
- Forum: Performance
- Topic: Valve springs
- Replies: 2
- Views: 3252
Valve springs
After contacting Performancesprings Australia, and Eibach springs, both confirmed the dual springs they supply for all engines have a friction fit. Performancesprings were able to supply me inner springs wound left hand, same spring rate and height, and had the correct sliding friction fit :) I noti...
- Thu Nov 02, 2006 8:02 pm
- Forum: Performance
- Topic: Valve springs
- Replies: 2
- Views: 3252
Valve springs
I have a set of new shankle valve springs for a 4 cyl. purchased a few years ago. I know this subject was about earlier. These springs have a foil damper in between the inner and outer coils. It is advised this damper be removed before installing the spring set. My concern is having the inner and ou...
- Thu Oct 19, 2006 3:34 pm
- Forum: Engine
- Topic: 2.0 4cyl max liner bore
- Replies: 16
- Views: 13397
2.0 4cyl max liner bore
Not so impossible Mats. As I said if you use an aftermarket rod (such as Carillo or similar) the clearance between the bottom of the cylinder and big end section of the rod is increased. I found out after fitting such rods to my block. As for piston skirt to crank counterweights, well you would be u...
- Thu Oct 19, 2006 3:31 am
- Forum: Engine
- Topic: 2.0 4cyl max liner bore
- Replies: 16
- Views: 13397
2.0 4cyl max liner bore
I am currently building a Nord engine with a TS head and 85mm pistons. I had my stock liners bored to 85 mm but have now decided to junk them for a set of custom ductile liners. I have seen and heard of many cracked cylinder liners with 2.0 race engines, and after spending a lot of time and money I ...