Corvair DiagramCorvair Photo
Corvair Center
home forum corvairs calendar links Corvair Podcast
California Corvairs
Clarks Corvair
Clarks Corvair
“CORSA"



Chevy Corvair License Plate
Chevy Corvair Chrome Wheel
Corvair Center Forum :  Corvair Center Phorum The fastest message board... ever.
Corvair Center 
Current Page: 3 of 5
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: jjohnsonjo ()
Date: February 19, 2019 06:03PM

Matt, I kinda agree with Joel on this. Now a days you can get very low expansion forged pistons and multi weight synthetic oils like 5/30 or 5/40/. We all know that the Vair main clearance grows by at least .001" at temp. So loose is good for racing and high viscosity oil. My last build was at the tight end of every spec. it runs great. If I crawl under it when its hot and running the lack of mechanical noise is unbelievable, you would never think its an air cooled engine.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

Image and video hosting by TinyPic

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 20, 2019 09:44AM

Items to help oiling in crankcase.

Drill out flash in drain holes to 3/8



increased width of oil groove behind main bearings to 3/16 (still need to stone them smoother)

Also checked oil feed hole diameter, gage pined at .188



I increased the hole to .212 with a reamer I had, didn't want to go too big and risk breaking out the side.

You can see the difference in pic (only started this one and took pic). Should help a bit.



-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY



Edited 1 time(s). Last edit at 02/20/2019 09:45AM by toms73novass.

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 20, 2019 03:13PM

Case cleaned up:



And cleaned some more, 3x



Your not done till nothing comes out!!!!!!


Looks like all the main bores are within .0005 of each other checked in multiple orientations , Happy Days!



-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: jjohnsonjo ()
Date: February 20, 2019 03:39PM

Sounds great, how are the cam journals? Also, make sure the cam is true.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

Image and video hosting by TinyPic

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 20, 2019 03:44PM

jjohnsonjo Wrote:
-------------------------------------------------------
> Sounds great, how are the cam journals? Also, make
> sure the cam is true.


Still have to measure the cam journals, they look OK.

Have a new American PI TB-25 cam, it had better be straight !

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 21, 2019 02:11PM

More updates today:

When I did the ring test on the crank, down near 5-6 it didn't have quite the tone of the other areas on the crank.

I did a dye test and did not find anything so to be safe I took it to the local machine shop to have it magnafluxed.

I was given a clean bill of health, better to be safe than sorry.

I tackled the rods, picked out what looked like a nice set in the stash, just dirty. Cleaned them up in the vapor blaster:





Took out the bolts and took off the burrs on the mating surfaces on a diamond stone. (barely took off much)



Installed ARP bolts and plastigaged all the rod bearing on the crank.

All measurements turned out nice.



-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: MattNall ()
Date: February 21, 2019 02:42PM

Great progress!





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

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: 63turbo ()
Date: February 21, 2019 09:06PM

toms73novass Wrote:
-------------------------------------------------------
> jjohnsonjo Wrote:
> --------------------------------------------------
> -----
> > Sounds great, how are the cam journals? Also,
> make
> > sure the cam is true.
>
>
> Still have to measure the cam journals, they look
> OK.
>
> Have a new American PI TB-25 cam, it had better be
> straight !

THAT'S The Total BADAXX turbo cam!! I love that cam!! you
be hanging on for dear life once you get that crate rolling!smileys with beer

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

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



Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: REM654DPG ()
Date: February 21, 2019 09:40PM

Tom, just a couple recommendations. Before you get too far into the assembly I would encourage you to have the flywheel/gear hub pressed off and the key changed out with a new one or the performance MR. Gasket #720-984G. You’ll need a fixture for that. If you skip this important step you will regret it if the old key lets go and you have to start all over again. Next, as the spec sheet from the ARP rod bolts say on line 7, your connecting rods really need to be reconditioned now that you changed them out as they won’t be round. If anything you need to check them on a connecting rod bore gage shown in the picture to verify how round they are. Even if they plastigaged good I would still be concerned. And, check the pin bores on the gage as shown to verify that they have enough press fit as sometimes they don’t – you want .0008 minimum after a touch hone. Then, be sure to have the rods correctly aligned after installing the pistons. And last, main bearing clearance is critical on an aluminum case if you want longevity out of this engine. If you can’t get the right combination of bearings for the standard size the best way to set up the mains on a nitrided Corvair shaft is to custom grind the mains only at .010 under. Install the bearings and measure the I.D. with your bore gage and subtract .0015 to .002 max and give those numbers to the crank grinder. All these small details will give you a bottom end that is blueprinted and will hold up much longer in a turbo/performance application.

Regan Metcalf
Portland, OR

Attachments:

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 22, 2019 04:52AM

Regan,

Thanks for the info, I will replace the key!

I did use gage pins on the rod pin bores and have at least .001 press.

I also did measure out of round on the large ends, if you look on the rods the measurements are written on them, however, I need to go back and re do that because that is before the arp bolts were installed. At that point I was seeing a variation if .0002-.0003 which I though was acceptable.

Thanks for all the good info!

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 22, 2019 05:07PM

Since 5 of the 6 pistons were heavier than the 6th by 12g I had to come up with a plan to remove material with out weakening the piston. I read several articles that said to take it out from under to top of the piston with out going too deep.

I ended up using a large bull nose end mill to prevent sharp corners and used my rotary indexer with a chuck to hold the pistons (with a copper shim).



What the underside looks like, fortunately didn't have to go too deep, because I still need to mill off some of the crown to lower compression:



My target weight, all exactly the same:



And yes, pin weight also done.

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: REM654DPG ()
Date: February 22, 2019 05:27PM

Looking good Tom nice scale. If you want to maintain the squish area when you mill the tops down try to machine it with the D shape dish. Also be sure to check the pin bores in the piston for adequate clearance needed for turbo temps. You want a minimum of .0006 - you can also deburr the corners of the oil slot for what it's worth as that's the weak spot in these pistons.

Regan Metcalf
Portland, OR

Attachments:

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 22, 2019 06:12PM

Regan, once again thanks for all the helpful info! thumbs up

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: jjohnsonjo ()
Date: February 22, 2019 06:16PM

toms73novass Wrote:
-------------------------------------------------------
> Since 5 of the 6 pistons were heavier than the 6th
> by 12g I had to come up with a plan to remove
> material with out weakening the piston.

That is surprising, my set of those were just about dead on, maybe a 10th of a gram off.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

Image and video hosting by TinyPic

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: jjohnsonjo ()
Date: February 22, 2019 06:20PM

REM654DPG Wrote:
-------------------------------------------------------
> Looking good Tom nice scale. If you want to
> maintain the squish area when you mill the tops
> down try to machine it with the D shape dish. Also
> be sure to check the pin bores in the piston for
> adequate clearance needed for turbo temps. You
> want a minimum of .0006 - you can also deburr the
> corners of the oil slot for what it's worth as
> that's the weak spot in these pistons.


I like those pistons and wanted to do it like that. No local machine shops would bite (lost art around here) I just had .070" taken off half the piston, works fine. I did radius the ends of the oil grooves.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

Image and video hosting by TinyPic

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 22, 2019 06:26PM

jjohnsonjo Wrote:
-------------------------------------------------------

> That is surprising, my set of those were just
> about dead on, maybe a 10th of a gram off.

I'm sure the 6th piston was a newer piston the others I think are older.

The person who had these before really had no idea what they were doing. They were run for a very short time (I was told), but I put the rod/piston assemblies on the scale and they were BONKERS out of balance between sets! So I had them taken apart by a machine shop so I didn't mess them up. The engine probably shimmied like crazy.

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: 63turbo ()
Date: February 22, 2019 06:56PM

toms73novass Wrote:
-------------------------------------------------------
> Regan,
>
> Thanks for the info, I will replace the key!
>
Another option might be to not remove the crank hub, but
press a 1/4" dowel pin opposite the original key... both
cranks that I've done got this treatment. A couple of advantages
to doing this instead of removing the crank hub are that it
is much easier, and the hub doesn't loose so much press
from being taken off. I've been told that the force required
to remove a crank hub from an unmolested crank is MUCH higher
than it takes to push back on. By not removing the hub you
keep that extra press, plus the extra shear area added by pressing
another pin in. I haven't had a crank hub come off yet!

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

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



Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: toms73novass ()
Date: February 22, 2019 07:24PM

I am assuming a hole for the pin is drilled half in crank and half in gear and pin pressed in? With a press fit.

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY



Edited 1 time(s). Last edit at 02/22/2019 07:25PM by toms73novass.

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: REM654DPG ()
Date: February 22, 2019 07:41PM

I haven't tried the dowel pin method yet as I've always had good results changing the key. However I know many others have good success with the pins so that's another good option too. You'll need to make a fixture plate that will allow you to hang/clamp the crank off the side of the mill table and drill it straight on. I wish you well Tom.

Regan Metcalf
Portland, OR

Options: ReplyQuote
Re: Down the rabbit hole, blow through turbo 140 build smoking smiley
Posted by: 63turbo ()
Date: February 22, 2019 07:42PM

toms73novass Wrote:
-------------------------------------------------------
> I am assuming a hole for the pin is drilled half
> in crank and half in gear and pin pressed in?
> With a press fit.

Absolutely! Put the center of the mill spindle axis over the
interface between the crank and hub, plunge cut a relief into
the snout of the crank, drill and ream a hole for a interference
fit for a 1/4" dowel pin. Press the pin flush to the crank hub
and finished! When I did mine, I seem to remember the pin being
.875" long.

I did make a tool to hold the crank on the mill table... Ray
Sedman now has that tool!

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

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






Edited 1 time(s). Last edit at 02/22/2019 07:49PM by 63turbo.

Options: ReplyQuote
Current Page: 3 of 5


Sorry, only registered users may post in this forum.
This forum powered by Phorum.