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Con rod query - Colin Wilks - 24-11-2018
I am hoping to reuse my standard 1.5” white metalled rods in my sports engine rebuild (after balancing and renewing the white metal). The gudgeon pins are fully floating so there are no pinch bolts on the little ends to worry about. Doing some homework on availability of new / decent second hand rods the choice seems to be Phoenix, Hadley or original Austin.
A couple of people have warned me off Phoenix rods as they are not drilled so as to encourage the flow of oil across the big ends.
Clearly I can drill them myself if needed, but I'm confused as to why people may be selling rods for Austin Sevens that apparently are less than ideal?
Be grateful to hear people's experience and advice.
RE: Con rod query - Tony Betts - 24-11-2018
Hi Colin,
Be cearful over what you listen too.
Everyone's an expert. Or at least able to repeat what the last person sed.
Pheonix rods are fine, and have been fitted to many race engines over the years.
They are made for pressure fed engines initially, so undrilled.
If you want to fit them to splash engines, then drill the holes.
Tony.
RE: Con rod query - Robert Foreman - 24-11-2018
Colin ,
when you come to examine the original rod little ends I would be very surprised if they are not worn.
This is due to the two oil holes drilled from underneath on the thrust side of the little end.
All of the ones I have measured have been worn and as the top of the rod is so thin oversize pins are not really an option.
RE: Con rod query - Ruairidh Dunford - 24-11-2018
(24-11-2018, 06:20 PM)Tony Betts Wrote: They are made for pressure fed engines initially, so undrilled.
If you want to fit them to splash engines, then drill the holes.
Hi Tony,
have you done this modification to Pheonix rods yourself and, if so, how and what exactly did you do please?
RE: Con rod query - Zetomagneto - 24-11-2018
(24-11-2018, 06:20 PM)Tony Betts Wrote: Hi Colin,Tony, I am confused by your answer, drill them for splash fed? Where, and why?
Be cearful over what you listen too.
Everyone's an expert. Or at least able to repeat what the last person sed.
Pheonix rods are fine, and have been fitted to many race engines over the years.
They are made for pressure fed engines initially, so undrilled.
If you want to fit them to splash engines, then drill the holes.
Tony.
Usual to drill no 4 rod on pressure fed.
Never heard of any problems with Phoenix rods.
(24-11-2018, 05:35 PM)Colin Wilks Wrote: I am hoping to reuse my standard 1.5” white metalled rods in my sports engine rebuild (after balancing and renewing the white metal). The gudgeon pins are fully floating so there are no pinch bolts on the little ends to worry about. Doing some homework on availability of new / decent second hand rods the choice seems to be Phoenix, Harland or original Austin.Colin if your rods need remetaling, bearing in mind the cost of this you may as well,for the extra cost involved get a new set of Conrods, as many others will say, Phoenix are fine.
A couple of people have warned me off Phoenix rods as they are not drilled so as to encourage the flow of oil across the big ends.
Clearly I can drill them myself if needed, but I'm confused as to why people may be selling rods for Austin Sevens that apparently are less than ideal?
Be grateful to hear people's experience and advice.
RE: Con rod query - Bob Culver - 24-11-2018
Long ago when my car was in hard everyday use, and I was very inexperienced, I had the rods remetalled. I had noticed that the babbit was more scored on the trailing side of the trench. And I had seen all the diagrams in books showing the very destructive effects on oil film of grooves etc. So I installed with no holes. (Unfortunately filling the holes with screws) The car has been held at 4.000 rpm for long stretches and 50 mph ditto and after about 20,000 miles the big ends appear unmarked. However many maintain the holes are vital, and presumably Austin had a reason. Whether oil net entered or exited is uncertain, but I suspect act as air reliefs to facilitate oil flow. But I am not sure that the trench is necessary or desirable, or whether all models had originally. (Probably only 19 or so bhp)
(All illustrated in Ruairidh’s recent photos under Ring a Ding...)
RE: Con rod query - Zetomagneto - 24-11-2018
(24-11-2018, 10:47 PM)Bob Culver Wrote: Long ago when my car was in hard everyday use, and I was very inexperienced, I had the rods remetalled. I had noticed that the babbit was more scored on the trailing side of the trench. And I had seen all the diagrams in books showing the very destructive effects on oil film of grooves etc. So I installed with no holes. (Unfortunately filling the holes with screws) The car has been held at 4.000 rpm for long stretches and 50 mph ditto and after about 20,000 miles the big ends appear unmarked. However many maintain the holes are vital, and presumably Austin had a reason. Whether oil net entered or exited is uncertain, but I suspect act as air reliefs to facilitate oil flow. But I am not sure that the trench is necessary or desirable, or whether all models had originally.These are shell bearings in Phoenix rods, no trench
(All illustrated in Ruairidh’s recent photos under Ring a Ding...)
RE: Con rod query - Tony Betts - 25-11-2018
(24-11-2018, 08:32 PM)Ruairidh Dunford Wrote:Hi R,(24-11-2018, 06:20 PM)Tony Betts Wrote: They are made for pressure fed engines initially, so undrilled.
If you want to fit them to splash engines, then drill the holes.
Hi Tony,
have you done this modification to Pheonix rods yourself and, if so, how and what exactly did you do please?
Never had to do it, I'm like you. I'd use 1 5/16 with GOOD GOOD GOOD austin rods. I think even if I wanted to go racing, INITIALLY I'd go the same way.
The must have for useing new rods happend around 10 years ago, it happend because the supply of GOOD original rods were running out.
I have NO problem with original 1 1/2 rods, but as Robert points out. They have to be in GOOD condition.
If I was to build the next engine with 1 1/2. It would be pressure fed with HADLEY rods.
Pheonix rods as I say are fine, but they are a modern version of the original. ie made to fit sports engines. If fitting them to standard crankcasses they at least come to close to the sides, and even hit on some crankcasses. And the already thin case has to be ground away.
The HADLEY rods were developed to get around this problem amongst others.
A renault rod is cut on a 43 degree angle on the big end, and almost gives enough Clarence.
So the HADLEY rod was cut on a 45 degree angle, and gives enough clearance.
Rather than rushing the Hadley to market to beat the rest, they were held back to sort other big end and small end problems others were getting on crankcase Clarence, and being able to use all types of Pistons, without having to make mods to the rods first.
Tony.
RE: Con rod query - Ruairidh Dunford - 25-11-2018
Thank you Tony.
RE: Con rod query - Terrytuned - 25-11-2018
Drilling rods.
Terry.