8.1 inch rod in stock block/stroke 350 and -----

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GARY C
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by GARY C »

David Vizard wrote: Sat Oct 07, 2017 6:08 pm So after the uproar this simple post produced here is the answer to how this all goes together.

First the block;- This had new thick wall liners installed in every cylinder. Prior to boring to size the blocks water jacket was filled with concrete.

The bores were then prepped as accuratly as possible to the 5 different bore sizes than I most often use. Together with the long rods this is how the block will be used.

Firstly the pistons have the crown machined with a hole that will accommodate the rod coming through. The piston is then mounted on the rod upside down. With the wrist pin above the top of the deck it can easily be removed to allow the piston to be removed from the top of the block. The reason for this is so I can quickly access the rings and replace them as required. The rotating assembly will be turned over at about 200 rpm max (I did say as a clue that the rods would last almost for ever even though they are welded) The purpose of this 'fixture' is as a ring break-in and polishing machine.

Why go to all this trouble? Because my previous method was too time consuming and time is the one thing I am short of.

Using a proprietory oil blend the rings will not only be polished but also the surfaces will receive a very thin layer (about 100th of a thou) of hard ceramic coating.

Try this little exercise next time you build a short block. After it is all together get a long breaker bar and turn the short block over about a half dozen time as fast as you can. Now take a sniff of the block.The chances are you will smell burnt oil caused by the new rings micro welding to the bore. To produce that smell temperatures need to go significantly over 400 F. Just give this a thought for a moment. That micro welding goes on during break-in and only stops (or nearly so) after a fully developed inter-component surface and oil film has been generated. In essence the rings do the final machining on the bores.

Why am I going to all this trouble? easy answer I can't afford to reduce piston assemble to bore friction the way it is done on F1 engines so I have had to come up with my own affordable solution.

Not only does this ring break-in fixture polish and plate the rings but also can be used to measure the the turning torque as the block is supported at a level just above it's longitudinal axis. A torque arm to the frame holding the block allows for load cell output to register the turning torque.

So how well does it work? With the bores prepped in the manner I use which is a double deal (cross hatch applied first and then a very fine vertical platue finish on top) it works very well. In a worst case scenario it cuts friction in half and in a best case scenario it cuts it by over 75%.

For example the initial turning torque my 383 Chevy short block builds usually runs around 18-20 lbs-ft when done in a conventional fashion. Prepping them as described here the turning torque is typically 5-6 lbs-ft. As for wear, when used with a top quality oil, the measured wear is extremely low to non-existent. My Cup car Dodge engine had 1500 race miles on it and exhibited no measurable wear in rings or bores. In fact it looked like it had never been run.

Just a further note here. The ceramic plating on the rings won't micro-weld to the bore material.
DV
For PDQ!
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by GARY C »

pdq67 wrote: Sat Oct 28, 2017 2:11 am I haven't read the complete thread so David, just how are you installing an 8.1" long rod in a 350" SBC engine??

Curious minds want to know!

In the other thread about the big pistons, I have asked how much can the Dart block that will bore to 4.25" be offset bored for max. dia. cylinders"

pdq67
If your referring to the one in the general forum that was someone making fun of this thread! Look up, I just posted what you was looking for.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by pdq67 »

Sorry, I guess I though DV was going to run it with an 8.1" long rod.

Thanks Gary, I just found it and read it over slowly.

pdq67
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by Mark O'Neal »

sanfordandson wrote: Fri Oct 27, 2017 10:09 am
Mark O'Neal wrote: Fri Oct 27, 2017 4:53 am
Ive been getting the mahle rings for around 170 a set in the 1mm size. I didnt think that was bad at all. I'm going to try the CP bullet line this winter in a few motors. 1mm, 1mm, 2mm ring pack, last ported lightweight flat tops for $720 a set with rings. IIRC the mahles were closer to $800.
I used Total Seal pricing, 170 isn't bad at all.

You'll be happy with the Bullet line, they're nice parts. They do a few thing I don't care for a lot, but nothing that would ever stop me from using them. That, and just because it doesn't make sense to me, doesn't necessarily it doesn't make sense.

The problem I have with ring manufacturers is getting rings with a spread so I can use the same rings setup on a range of bore sizes....and with a consistent choice of top rings. Not everyone wants to run moly, not everyone wants to run steel.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by tenxal »

A solution in search of a problem.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by RevTheory »

tenxal wrote: Sun Oct 29, 2017 8:02 am A solution in search of a problem.
Apparently a big time-saver for ring prep.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by MadBill »

After sixty years of engine building, I think David was likely pretty clear on the problem before coming up with this solution..
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by user-23911 »

Here's quick easy question(s) about seating rings (after reading comments on one of those ricer forums).
That's because that's what this topic is about?
Bedding in the rings.


If you've got a good block and it's still got a crosshatch, if you decide to change the pistons and keep the bore size the same........has anyone besides myself reused the rings without a problem.
A bad hone job with a ball hone is worse than no hone job at all?

True or false?

Modern engines with EFI don't suffer from bore wear like old ones did.
It's normal to strip them and still have a cross hatch.

For a road car / street machine.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by benno318 »

i have had a few modern diesels come in with cracked pistons from injector issues. apart from the piston with cracks, the bores appear excellent. of course, with most of these, the owner wants to spend as little as possible (if they didnt, injectors would have been replaced/serviced ages ago avoiding the problem in the first place)
one way i approach these jobs is to offer to simply replace pistons, refitting existing rings in the same bores, which means i dont have to strip the entire engine down to hone and clean everything properly. this saves many, many hours stripping the engine of all the timing gears, crank and everything else just to give a hone and cleanout.

works well - and if it wasnt using oil before, it still wont.
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by user-23911 »

Good to hear.
Yes...leaking injectors in diesels.
They do a lot of damage.
1KZ, 1KD. WLT. YD25. ZD30?

Getting back the this post.........
It's about seating the rings but in another block.
So in effect you're starting off with new rings.......using a spare block to machine the new rings.
Then remove them and fit them to the block they're going to be used in.
The new block?
That will be already honed?
SO the rings are machined by the block?
The block isn't machined by the rings?
Or a bit of both?
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard »

joe 90 wrote: Wed Nov 01, 2017 5:24 am Good to hear.
Yes...leaking injectors in diesels.
They do a lot of damage.
1KZ, 1KD. WLT. YD25. ZD30?

Getting back the this post.........
It's about seating the rings but in another block.
So in effect you're starting off with new rings.......using a spare block to machine the new rings.
Then remove them and fit them to the block they're going to be used in.
The new block?
That will be already honed?
SO the rings are machined by the block?
The block isn't machined by the rings?
Or a bit of both?
Slightly aside but here is an interesting bit of ring info I got straight from the 'Grump'. 'The second set of rings on a bore always make more power!'
David Vizard Small Group Performance Seminars - held about every 2 months. My shop or yours. Contact for seminar deails - davidvizardseminar@gmail.com for details.
user-29956

Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by user-29956 »

David Vizard wrote: Wed Nov 01, 2017 12:52 pm
joe 90 wrote: Wed Nov 01, 2017 5:24 am Good to hear.
Yes...leaking injectors in diesels.
They do a lot of damage.
1KZ, 1KD. WLT. YD25. ZD30?

Getting back the this post.........
It's about seating the rings but in another block.
So in effect you're starting off with new rings.......using a spare block to machine the new rings.
Then remove them and fit them to the block they're going to be used in.
The new block?
That will be already honed?
SO the rings are machined by the block?
The block isn't machined by the rings?
Or a bit of both?
Slightly aside but here is an interesting bit of ring info I got straight from the 'Grump'. 'The second set of rings on a bore always make more power!'
[*]The third makes 5 more horsepower than the 2nd set! [/i][/b]Not many people have been there though!

.......Vincent Dizziano
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by David Vizard »

Vee-Dizzie wrote: Wed Nov 01, 2017 1:53 pm
David Vizard wrote: Wed Nov 01, 2017 12:52 pm
joe 90 wrote: Wed Nov 01, 2017 5:24 am Good to hear.
Yes...leaking injectors in diesels.
They do a lot of damage.
1KZ, 1KD. WLT. YD25. ZD30?

Getting back the this post.........
It's about seating the rings but in another block.
So in effect you're starting off with new rings.......using a spare block to machine the new rings.
Then remove them and fit them to the block they're going to be used in.
The new block?
That will be already honed?
SO the rings are machined by the block?
The block isn't machined by the rings?
Or a bit of both?
Slightly aside but here is an interesting bit of ring info I got straight from the 'Grump'. 'The second set of rings on a bore always make more power!'
[*]The third makes 5 more horsepower than the 2nd set! [/i][/b]Not many people have been there though!

.......Vincent Dizziano


Well Vincent, Did Grumpy tell you that or is it your opinion or a new 'old wives tale'?

DV
David Vizard Small Group Performance Seminars - held about every 2 months. My shop or yours. Contact for seminar deails - davidvizardseminar@gmail.com for details.
user-29956

Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by user-29956 »

David Vizard wrote: Wed Nov 01, 2017 2:39 pm
Vee-Dizzie wrote: Wed Nov 01, 2017 1:53 pm
David Vizard wrote: Wed Nov 01, 2017 12:52 pm

Slightly aside but here is an interesting bit of ring info I got straight from the 'Grump'. 'The second set of rings on a bore always make more power!'
[*]The third makes 5 more horsepower than the 2nd set! [/i][/b]Not many people have been there though!

.......Vincent Dizziano


Well Vincent, Did Grumpy tell you that or is it your opinion or a new 'old wives tale'?

DV
Yes. CIRCA 1975ish. Ive also tested it many many times. Your free to ignore it of course though. I don't have to give these things away for free you know!
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Re: 8.1 inch rod in stock block/stroke 350 and -----

Post by GARY C »

I like the signature quotes, one my all time favorite is.
"You know your winning when your competition resorts to childish behavior"
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THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
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