Cranks and rods for 1275 builds
Total posts: 4134
Last post: Oct 13, 2020 Member since:Oct 8, 2011
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
Since I'm still treated like family when ever I drop in, I take full advantage of it. The current cost of removing bolts and reconditioning 4 rods runs $95. US. I have always removed rods with pistons then press the pistons off rods, box the pistons and tie wrap the rods as a set. I don't bother to clean them till I'm ready to work them. While pressing apart I watch the press gauge and mark any rod that the pin moves to easy. When I have four I tie wrap as a set. They can be converted to floating without bushing or fitted for a small end bushing. I have never been a fan of floating steel to steel but I know it is done and with enough clearance and a oil hole in the web to force feed the pin on the down stroke it will work. Speaking of floating most of the new rods I see for sale are either floated std pin and more and more 18 mm pin requiring a special piston. Even the reasonable ones are $1000. US. If you want to e mail me a link to press fit rods new or used feel free. I can spend a couple extra min. or two on rods for $1000. I have broken plenty of cranks only one came out the side of the engine but it did bring it's Cooper S rods with it. And they had been heavily lightened all over.
Think about it, anybody who can does their own work weather that's good or bad we wait to see. The people who can afford to have their work done want and expect a great result as well they should. They are also shocked as am I, at the cost of building a top shelf power unit. If building from a customers core one would expect the cyl. head casting, block, crank and rods would all be reused and they would be if all passed inspection. Build from a pile of left over parts does not sound like a great idea. As for blocks and heads we are kind of stuck. Everything else is easy enough new and heads can be bought new. I guess there is someone selling new blocks. Thanks for the feed back. Steve (CTR)
Total posts: 10237
Last post: Apr 9, 2024 Member since:Mar 24, 1999
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
Finding a good set of roughly matched weight rods, balancing them, peening them takes time & money and the supply is dwindling. I'll agree with Mur, comparing that to the cost of a brand new set of budget rods and it's a no-brainer really if you're paying someone to do the work.
CTR is the other side of that balance though - he's the one charging for the work and it's his livlihood... On the other hand, if I were Steve I'd be looking for a good trade deal on new rods and upsell them - the saving in time and effort would be mahoosive along with better quality control. Even the el-cheapo Chinese rods are better than 45 year old bent things.
Total posts: 5840
Last post: Nov 1, 2019 Member since:Nov 12, 1999
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
Total posts: 4134
Last post: Oct 13, 2020 Member since:Oct 8, 2011
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
Total posts: 4134
Last post: Oct 13, 2020 Member since:Oct 8, 2011
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
If I recall when the rolled radius cranks first appeared there was talk of grinding them till all the roll radius was gone and finishing with a proper ground radius.
If anyone has a set or two of metro rods I'd be interested in talking. I have lots of mini stuff and plan to have less next year. Steve (CTR)
Total posts: 438
Last post: Nov 13, 2022 Member since:Mar 27, 2002
|
Cars in Garage: 0
Photos: 15 WorkBench Posts: 0 |
|
Ron
Total posts: 10237
Last post: Apr 9, 2024 Member since:Mar 24, 1999
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
From memory, the 1100 cranks are EN16T as opposed to EN12T for the A+ cranks - although the stroke is longer and there is little or no overlap on the journals, they are still technically stronger.
For smoooooth street engines, I'm inclined to try using the 'Inno' rods - you know, the deeply unfashionable ones with the upgraded material spec but huuuge balance weights on the end cap.
My thought train is that the extra weight will help offset the reciprocating piston but not harm the rotating mass too badly as the weight is right in the centre. Coupled with a lightened flywheel and electronic ignition to damp out lumpiness at idle, I reckon it could be a winner for cruising in grand manner.
Grownups can have informed discussions from opposing viewpoints without resorting to silliness.
Total posts: 4134
Last post: Oct 13, 2020 Member since:Oct 8, 2011
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
Yes, I also have read why the cranks went larger on rods when a lesser material was chosen. I have also seen AA cranks off set ground .125 and greater to stroke. I have nothing against Metro rods just don't have a bunch of them.
Thanks for the reply and I respect your opinion just don't happen to agree. I have built engines using AA auto cranks some of which are small rod, lesser material. I spent 25 years working at an auto machine shop with two crank grinders running every day. What people don't realize is most cranks are now made of cast steel not forged steel. To make things better most rods are now made of powdered metal heated and formed into a rod like the newer rocker arms for minis.
I have thought about sending them for wedge and heat treatment as well. Don't think it will be required for street units.
Oh yeah, is the 1100 stroke as long or longer than a 1275 and what material and rod size do they run? Steve (CTR)
PS not looking for a fuss just sharing thoughts.
Total posts: 6469
Last post: Sep 29, 2022 Member since:Nov 2, 2006
|
Cars in Garage: 4
Photos: 1354 WorkBench Posts: 2 |
|
The A+ rods are up to almost any mayhem one can imagine with an A Series engine.
My 2nd set was being held for use in a Metro turbo build...still have them, the +20 Omega pistons, Longman head, and prepared crank.
Total posts: 10237
Last post: Apr 9, 2024 Member since:Mar 24, 1999
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
One of the reasons for going to 1.75" big ends from the smaller 1.625" S size was to allow for a lower grade of steel in the crank but nominally keep the same strength through having more material.
If you go down the route of reducing the diameter of the big ends just to use up the 1.625" rods don't use them in any customer performance engines...
A+ Metro rods are actually very good.
Total posts: 6349
Last post: Oct 22, 2023 Member since:Mar 9, 1999
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|
Total posts: 4134
Last post: Oct 13, 2020 Member since:Oct 8, 2011
|
Cars in Garage: 0
Photos: 0 WorkBench Posts: 0 |
|