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3.1 Liter Going Together
Posted by: Jonathan Knapp ()
Date: February 05, 2017 08:16PM

Here are some picture of my 3.1 Liter engine being assembled After seemingly years of planning, it is finally going together (hooray!). The first picture shows the polished std. crank with some of the grinding for balancing. The second one shows the American Pi rods all attached.

Jonathan Knapp
Seattle, WA
'66 Corsa Autocrosser

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Re: 3.1 Liter Going Together
Posted by: Jonathan Knapp ()
Date: February 05, 2017 08:18PM

Next up are pictures of the case and the internals. First the case is bare. Then the American Pi roller cam with adjustable cam gear. Then the crank with rods.

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Re: 3.1 Liter Going Together
Posted by: Jonathan Knapp ()
Date: February 05, 2017 08:24PM

Here you can see the crank gear with larger bolts drilled for larger flywheel bolts. It is also pinned to the crank. Then the other half of the case is put in place with rods protruding from enlarged cylinder holes. Finally, I installed the ARP case studs that tap into the reamed case holes. Everything was torqued and turns freely.

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Re: 3.1 Liter Going Together
Posted by: MattNall ()
Date: February 05, 2017 08:43PM

Geat patience on your part!





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: 3.1 Liter Going Together
Posted by: Jonathan Knapp ()
Date: February 05, 2017 11:13PM

Forgot to show a little bit more of the rods. Big ends are doweled with ARP bolts instead of studs/nuts. You can see the profile of the larger beam. Small ends are .810" and have full-floating pins.

Main bearings are std. size Clevitte 77s. Two sets are used to make all four main bearings the same (don't use the off-set one). Rods bearings are also std. size Clevitte 77s.

Next up is fitting the American Pi roller lifters and the lifter retaining bar. After that will be a test fit of the pistons, cylinders, and heads to set the valve timing on the adjustable cam gear and to check for piston to valve clearance.

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Re: 3.1 Liter Going Together
Posted by: 63turbo ()
Date: February 06, 2017 04:06PM

Jonathan- cool cool set-up, its great to see that project of yours finally coming together... I remember talking with you a few years ago about that when
you were still in the planning stages. One thing I'm curious about, what's that
brass(?) fitting in the block that seems to be in the same spot that the dipstick tube would go?

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: 3.1 Liter Going Together
Posted by: 406Vair ()
Date: February 06, 2017 08:17PM

Exciting! This type of project is on my wish list. I'll be watching this post with interest. Good luck!

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Re: 3.1 Liter Going Together
Posted by: Jonathan Knapp ()
Date: February 06, 2017 10:30PM

Hi Kevin,

The brass fitting is no big deal. Just a way to make the dipstick easily removable.

Jonathan Knapp
Seattle, WA
'66 Corsa Autocrosser

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Re: 3.1 Liter Going Together
Posted by: Jonathan Knapp ()
Date: February 06, 2017 10:54PM

Here is a close-up of the bottom of the roller lifter. The top side just looks like a regular hydraulic lifter. The long anodized bar is the lifter retainer bar. It keeps the lifters from rotating in the lifter bores. Fitting the retainer bar is a significant amount of work. In the third picture you can see the groove cut into the web of the block just outboard of the lifter bores. Then the bar had to be individually machined for the proper lifter-to-retainer bar clearance. All of them are between .003" and .006". You can see that in the second picture. That is a challenging job because, it turns out, the lifter bores are not all in the same plane or even parallel. Hopefully the minor lack of parallelism of the lifter bores will not adversely affect cam lobe or lifter roller wear. Quality control for the machining work at Chevrolet, at this time, was middling at best.

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Re: 3.1 Liter Going Together
Date: February 07, 2017 03:32AM

Great build, and I know the feeling of planning and waiting! I'm building a 3L and was wondering if you had dry assembled the case with the ARP studs and measured the main bores for roundness?

I'd like to use the ARP studs as well as I'm supercharging, but am concerned about bore roundness with the potentially higher clamp load of the ARP's due to the fine threads. I know when we would add studs to the mains on a big block, more than half the time we'd have to align bore them. Align boring the mains wouldn't be a big deal, but the cam bores would!

Just wondering what you found and if you could share it.

I'm excited for your build!

---------------------------------------------------------------------------------------------
You're unique, just like everyone else...

Johnny B
Central WI

Wife's '68, 3.0L, twin-screw compressor and fuel injected in the works...

Project Pressurized Pancake


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Re: 3.1 Liter Going Together
Posted by: v8vair ()
Date: February 07, 2017 09:33AM

Very Cool

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Re: 3.1 Liter Going Together
Posted by: larry202br ()
Date: February 07, 2017 11:18AM

I noticed you installed the rods on the crank before putting the crank in the block. Is that because you have floating wrist pins, or is that a normal way to do things? I'm guessing you can't press the pistons on after the connecting rods are installed, and the block halves are mated? One of the biggest PsITA I had was fitting a torque wrench in the block to torque the rod caps. Of course the pistons were already installed on the rods.

1961 rampside with a 65 / 67 110 engine, car four speed.
Now I have 1965 convertible as well, got it running in June, autocrossed in July 2016 at the convention!

KC0SKX
Olathe, ks
HACOA

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Re: 3.1 Liter Going Together
Posted by: MattNall ()
Date: February 07, 2017 11:20AM

Larry, you are correct...





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: 3.1 Liter Going Together
Posted by: thewolfe ()
Date: February 07, 2017 11:22AM

Droooooool....

Nate Wolfe
Portland OR
65 Corsa 180

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Re: 3.1 Liter Going Together
Posted by: Ratt643 ()
Date: February 07, 2017 01:07PM

I love it. Need a drooling imogy...Nice work!




1964 Monza Coupe

Maryville, TN
U.S. 129 The"Tail Of The Dragon"



Edited 1 time(s). Last edit at 02/07/2017 01:12PM by MattNall.

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Re: 3.1 Liter Going Together
Posted by: gnvair ()
Date: February 07, 2017 01:18PM

What brand connecting rods are those?

Lee J

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Re: 3.1 Liter Going Together
Posted by: Jonathan Knapp ()
Date: February 07, 2017 10:13PM

Johnny -
We started out with a known good block by clamping it with regular case bolt and checking it. Then, one by one we bored the case holes to the size of the stud shoulder. The boring starts on the right side but only goes about an inch and a quarter into the left side. After each case hole was bored the ARP stud was tapped into place from the right side, washers and nuts were installed and torqued. When all were done, the main bores were still the same. The rotating parts turn just as freely as they did when I first clamped it together with the stock case bolts before installing the ARP studs.

Larry -

I chose full floating pins just so I could assemble the engine this way. The plan further down the road calls for forced induction. At that point I can pull the heads and cylinders and replace the pistons with a dished piston to lower the compression ratio for the forced induction. I can do that without splitting the case, dropping the pan, or removing the top cover. New rings and cylinders will go on with the new dished pistons. The cam design is already set up for the forced induction.

Lee -

The rods are Sedman (American Pi): stock length.


Jonathan Knapp
Seattle, WA
'66 Corsa Autocrosser

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Re: 3.1 Liter Going Together
Date: February 08, 2017 03:35AM

Jonathan Knapp Wrote:
-------------------------------------------------------
> Johnny -
> We started out with a known good block by clamping
> it with regular case bolt and checking it. Then,
> one by one we bored the case holes to the size of
> the stud shoulder. The boring starts on the right
> side but only goes about an inch and a quarter
> into the left side. After each case hole was
> bored the ARP stud was tapped into place from the
> right side, washers and nuts were installed and
> torqued. When all were done, the main bores were
> still the same. The rotating parts turn just as
> freely as they did when I first clamped it
> together with the stock case bolts before
> installing the ARP studs.



Thanks much for the reply. This information allows me to go the ARP path with confidence. I will pre-assemble and check main and cam bores as well.

---------------------------------------------------------------------------------------------
You're unique, just like everyone else...

Johnny B
Central WI

Wife's '68, 3.0L, twin-screw compressor and fuel injected in the works...

Project Pressurized Pancake


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Re: 3.1 Liter Going Together
Posted by: larry202br ()
Date: February 08, 2017 04:12AM

I say thanks as well. Please continue to post progress. The stuff from American Pi is very impressive.

1961 rampside with a 65 / 67 110 engine, car four speed.
Now I have 1965 convertible as well, got it running in June, autocrossed in July 2016 at the convention!

KC0SKX
Olathe, ks
HACOA

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Re: 3.1 Liter Going Together
Posted by: Max Roeder ()
Date: February 08, 2017 04:27AM

PressurizedPancake Wrote:
-------------------------------------------------------
> Great build, and I know the feeling of planning
> and waiting! I'm building a 3L and was wondering
> if you had dry assembled the case with the ARP
> studs and measured the main bores for roundness?
>
>
> I'd like to use the ARP studs as well as I'm
> supercharging, but am concerned about bore
> roundness with the potentially higher clamp load
> of the ARP's due to the fine threads. I know when
> we would add studs to the mains on a big block,
> more than half the time we'd have to align bore
> them. Align boring the mains wouldn't be a big
> deal, but the cam bores would!
>
> Just wondering what you found and if you could
> share it.
>
> I'm excited for your build!

There should not be any higher clamp loads due to the finer threads on the ARP studs if the correct correlated torque is applied. Finer threads are stronger threads because of the larger cross section of the threaded area. For similar torquing they do provide higher clamping forces compared to coarse thread. Coarse threads go deeper into the bolt/ screw base material and reduce the cross section thus reducing their yield/ failure strength.

Although I don't remember the torque recommendations for the ARP studs and I don't know of any stretch of the standard block bolts with specified torque, that question is a different set of answers. I don't remember what the ARP block stud torque specs are, does anyone know if they are published?

The actual purpose of the ARP studs is to form eight dowel pins locating the block in it's intended original machined position. With the eight added dowel pins vs the two original the intent is to form a much more stiff block. There is a very specific installation and machining procedure for these ARP studs. A stiffer block is much less likely to move, i.e., maintaining crank bore and cam bore alignment, under heavy loading. To float the ARP block studs would be to eliminate their original purpose.

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