Rods for the 1592cc motor

[sunbeam74]

Tom,

Mine could have been 485.00 with shipping. I would need to check the reciept - it has been 3 or so years since I had bought the set.... they were the cheapest I had talked with and could deliver within a reasonable schedule.

I thought the quality was very good.

Steve

 

[Tom H]

Steve, just so you understand, it was your posting and pictures that caused me to go to Venolia. I sent your pictures and used your pistons as a "model" for mine. But I gave them my specific dimensions (and dished top)

Tom

 

[sunbeam74]

Tom,

Yes, I remember we exchanged a few e-mails. I still think they were the best value on the market. I forget who else I had quotes from but all were more expensive and the delivery time were longer.

What did you think of them? I was very pleased. The only thing I did different with the second engine build was a change to Total Seal rings.


Steve

 

[jumpinjan]

Well, I need about 4 sets and I need to contact them pretty soon. What do I need to tell them? I wonder if they will remember what a Sunbeam is, and your orders.
I also need to firm up the rod that I'm going to use. I'm not consider a stroked 1725, I want to include the 1600. Actually, the 1600 has more consideration right now for these pistons. So thats the criteria I going with, when I talk to them.
Jan

 

[sunbeam74]

Jan,

I sent a letter and a piston example which stated:

"Please review the enclosed piston. I would like to have this piston reproduced but with a few changes:

1) The piston should fit a 3.270†cylinder bore.

2) Compression height should be 1.900â€
(The piston sample in this package is 1.850â€)

3) Wrist pin should be 0.927†with spiroloc retainers

4) The top of the piston should be FLAT (not dished like the included example)

Upon receiving this package would you please contact me to finalize details?
"


Because of damage to the cylinder bores I had the shop clean up the block first. The machine shop came back with 3.270".

Steve

 

[Tom H]

I think they'll know what an Alpine is. I gave them pretty much the same info that Steve did. But I also gave them an overall height. We had a discussion about the pin fit. We ended up deciding on an interference fit of the pin in the piston leaving it up to my machine shop to hone it or not depending on if we wanted it to float in both the piston and rod. I ended up floating it in both.

Also had some discussion about the arc on the bottom. As best I can recall, I tried to spec the distance between the bottom of the pin and the top of the arc, but they said that dimension was simply whatever resulted from their standard arc and the overal piston length. Or maybe it was vice versa. But the result was a nice piston.

Tom

 

[owakip]

1592 motor with I6 rods

Very interested in this thread. I run a 1959 Buckler Mk17 with 1592cc Sunbeam Alpine running gear, out hear in New Zealand.. I just converted the motor to Chev I6 rods and bored it out for Holden 161 ci (Australian in line 6) pistons or 85.7mm.. May have been a bit ambitious.. as not long after running it in, and in the heat of my first race.. it let go.. big time... a hole in the block that you could clap your hands in... a rod had gone through # 2 cylinder.On pulling the engine down all the other 3 bores/pistons looked fine. The problem was #2 and #3 big ends had become very hot and # 2 seized and broke across the BE cap (bolts still intact). I am at a loss as to know why as all the BE clearances were fine on assembling the motor + had good oil pressure up to the explosion (50lb + ) . I run an Accusump and it still has 20lb in it + the middle main bearing ( which from memory feeds onto #2 and #3 BEs) looks fine. I would appreciate any thoughts you may have on the cause. Thanks.

 

[RootesRacer]

Well you did do most of the right things.

Based on the dollars you probably spent, I'd have gone the extra mile and used H beam rods, these would not likely have failed, you'd have snapped the crank first.

 

[sunbeam74]

It is surprising that it let go. If #2 and #3 showed signs of overheating then clearly there had to be some type of oiling issue going on. You'll have to keep us posted if you find anything.

There are minor things that can be done to the passages for #2+#3 to improve the flow since they share oil feed. (In fact Jerry Titus wrote about this in the series "Race Tuning a Sunbeam Alpine" for Sports Car Graphic (1962 issues, August and I can't remember the other month. They never published the last installment but I have it))

In general, the Chevy rod treatment has been used for a while... in fact, the earliest racing use I know of was in the 70's.

Steve

 

[sunbeam74]

BTW< post a nicer photo of the Buckler. It is a neat sports racer.

STeve

 

[owakip]

Thanks for your comments so far ..I have attached a couple of photos, (as requested by Steve).
Regards

Peter W

 

[puff4]

Nice Buckler! And quite rare. Tell me, is that a cast alloy plenum for the intake?

 

[owakip]

No it's fabricated out of sheet alloy

 

[owakip]

I had a thought regarding my question on what was the likely cause for the failure of BEs 2 and 3 in my 1592cc motor with Chevy I6 rods..given that the centre main bearing/journal (which feeds them) looks fine + the motor had good systemic oil pressure at the time of failure. Could it be that the BE bearing shells in # 2 and 3 started spinning and caused the failure?... If this is a likely cause .. I read elsewhere in this forum that you can "pin" them ... What is the recommended method for doing this? Thanks