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Crank center line shifted?
Posted by: Willt65 ()
Date: March 29, 2020 05:42PM

After getting my car on the road last year and having a blast beating the tar out of it, I decided I wanted to pull the engine and make it run better. With the setup that I had I thought that it just should have done better that it did.
6 into 1 intake, 280 iski cam, headers, etc... It still only wanted to rev easily to 5500 and no more that 6000 RPM, making power. I want to make power up to 6500 anyway. My plan was to pull the heads and get the head gasket step removed, so I could get the proper squish among several other things. To start I pulled the plugs and measured the existing squish for a baseline, using solid core solder.
Below are the numbers I got. Cylinders 1 and 2 being even, however 5 and 6 are shifted 0.010", with 3 and 4 shifted though not as bad. I am wanting to get my squish dialed in at 0.025" - 0.030". With what I am seeing this will not be easy.
Any suggestions?


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Crank center line shifted?
Posted by: Willt65 ()
Date: March 29, 2020 05:50PM

You might be wondering why I relocated the oil filter to the other side. I was planning on building a box under my intake to run hot oil through, due to it getting frosty. I have what would be a intake bypass valve on that side with ports to run the oil to the intake. Right now I am just bypassing the valve with another line to keep someone from closing it and causing obvious problems. This was just me looking ahead at what I wanted to do. Makes for questions, so I though I would tell you now!


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Crank center line shifted?
Posted by: Willt65 ()
Date: March 29, 2020 05:55PM

Also I'm running lubricator lines to the valve covers to lube the rocker arms.
I'm running Ford roller tip rockers and they don't have the proper lube hole so I did this. I now have some drill bits to fix that, so that's on the list too.


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Crank center line shifted?
Posted by: jjohnsonjo ()
Date: March 29, 2020 06:00PM

Willt65 Wrote:
-------------------------------------------------------
> Also I'm running lubricator lines to the valve covers to lube the rocker arms.
> I'm running Ford roller tip rockers and they don't have the proper lube hole so I did this. I now have some drill bits to fix that, so that's on the list too.

I went through a bunch of carbide tipped bits.

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


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Re: Crank center line shifted?
Posted by: cnicol ()
Date: March 29, 2020 06:13PM

I wonder if the shift you're seeing has anything to do with the purposely offset front main bearing? I don't recall the offset (is it .0005" .001" ??). I can't imagine it was .010" but waiting for someone to post the real offset dimension.

The offset was implemented very early on as a countermeasure to crankshaft knocking at idle.

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
61 Seamist Jade Rampside 140 PG
60 Monza coupe (sold, sniff sniff)
66 Sprint Corsa convt - First car! Re-purchased 43 years later
2+2 gnatsuM 5691

+17 Tons of parts

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Re: Crank center line shifted?
Posted by: Chilly Willy ()
Date: March 29, 2020 06:25PM

?

[corvaircenter.com]




The Corvair, Keeping Nader Notorious winking smiley


Will
Northern California

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Re: Crank center line shifted?
Posted by: Chilly Willy ()
Date: March 29, 2020 06:29PM

Is this the first time you’ve checked for squish on this motor?
I’d cc the heads and use a dial gauge on the pistons.




The Corvair, Keeping Nader Notorious winking smiley


Will
Northern California

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Re: Crank center line shifted?
Posted by: Brizo ()
Date: March 29, 2020 06:29PM

I thought the main bearing off-set was straight down toward the cam..? Which I don't think would effect the squish area measurement.?

However, the only trouble with the "solder squish" method is, since the squish area is not right above the piston pin, the result may be inaccurate because of piston rock.

Dan Brizendine, Circle City Corvairs
'64 8door Greenbrier 140 PG. "In beautiful Wanamaker Indiana...with one stop light and 5 pizza shops"

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Re: Crank center line shifted?
Posted by: v8vair ()
Date: March 29, 2020 06:39PM

You need a better way to check that, But you being stuck at 5500 could be a few things, Valve springs would be my first guess, 2nd would be ignition, even a set of good points will go to 7200, 3rd would be carb, ifs its a 390 that's not much better than 4 rochesters. What are your valve springs ? Ignition ? Carb Jetting ? I like spraying oil on the rockers/valve springs, the more oil in the valve covers the better for cooling

1965 Crown V8 Racer
1964 Bill Thomas Monza Replica Racer
1964 Spyder Street Car
1979 Mazda RX7

Mike Levine



Edited 1 time(s). Last edit at 03/29/2020 06:41PM by v8vair.

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Re: Crank center line shifted?
Posted by: Willt65 ()
Date: March 29, 2020 07:21PM

My valve springs are what are recommended with the cam, been to long to remember off the top of my head, but they were much stiffer that stock, and I have set all of the installed heights. The carb is a Holley 625 street demon, which has it's primary barrels very much like a 750 quadrajet and the secondary is vacuum. I have an O2 sensor in place to help jet the carb, though the exhaust did look very rich. The ignition is an ignighter II.
I realize that my numbers could be off due to what Dan Brizendine is saying, and I won't know fully what it is till I remove the heads and check deck height. Just looking how the numbers came out, it's unlikely that the error would be equally off both ways. Just wanted to run what I found by you all to see what experience says!
After seeing how rich thinks looked in the exhaust, I think I want to go ahead and pull the trigger and go multiport injected. Will have to come up with some funds first however, so well see how that goes. I know I would have better power if it wasn't so rich, though WOT the O2 sensor would be around 12:1. And it would be 13 - 14 normal driving with the O2.

I just want to know that I have the engine right before installing injection. I guess I'll pull the heads and make some checks to see what I really have.
Thanks!


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Crank center line shifted?
Posted by: Willt65 ()
Date: March 29, 2020 07:27PM

If you look at the exhaust you can see how rich it looked. I had a knock in the engine that started about 1/4 mile before getting home on my last ride before winter. You can see Number 4 has no carbon. The intake valve head bold backed out on number 4 causing the knock and the lean cylinder. Seen that tonight when I took the valve cover off. Figured it was something like that.


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Crank center line shifted?
Posted by: MattNall ()
Date: March 29, 2020 07:30PM

I'd say start by cutting the steps, then CCing the Chambers.Hopefully less labor.

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: Crank center line shifted?
Posted by: vairmech ()
Date: March 29, 2020 07:46PM

What rods are you running? Stock? If you are running stock rods they are NOT very even! The production tolerance was .004" on length but I found a set that was .010" difference. You can also use Playdough for that check.

Also keep in mind of what RPM you want to redline at. If you want over 6000 rpm you better keep at least .040" piston to deck clearance. The numbers you have look like a stock head with the step still in place. Remove the step, use anything but stock Corvair valve springs and that should get you going. There just might be something else going on, I used to take stock 140 engines to 6000 all the time, the 304 cammed ones wanted to keep going.

The other thing is the cam gear timing. Aftermarket gears are marked in such a manner that it is hard to tell if you have the correct tooth.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: Crank center line shifted?
Posted by: jjohnsonjo ()
Date: March 30, 2020 05:41AM

Did your compression variations fall in line with your solder tests?

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


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Re: Crank center line shifted?
Posted by: Willt65 ()
Date: March 30, 2020 06:06AM

I have the engine pulled out, and I didn't do a compression test before hand. Poor planning, I would have liked to of had that info! Lesson to self learned!

I am running stock rods with forged pistons, never thought about rod length being off.
I am planning on degreeing the cam, that is what I was thinking might be my issue. I installed the cam straight up and never checked it. I'll find out soon if thats my issue, I suspect its not right per the card. If the cam checks out fine, I am thinking about getting a set of Rhoads lifters, so I can get my bottom end back, and a little vacuum. You mention the 304 cam, is that a good all around performance cam? Looking for a fun street/autocross car.

Question, how many degrees difference does a tooth make on the gear?

Where can I get the equipment to cc my chambers?


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Crank center line shifted?
Posted by: Wagon Master ()
Date: March 30, 2020 06:19AM

Each camshaft gear tooth is approximately 7°.
That is camshaft degrees, or 14 crankshaft degrees.


'29 Ford Model A Tudor
'61 700 Lakewood 110 4 speed
'69 Monza Convert. 140 Auto.
'70 Dodge Challenger R/T 440 4 speed

Been aircooled since 1973
Northwest Ohio



Edited 1 time(s). Last edit at 03/30/2020 06:21AM by Wagon Master.

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Re: Crank center line shifted?
Posted by: Willt65 ()
Date: March 30, 2020 06:49AM

Thanks!


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Crank center line shifted?
Posted by: 63turbo ()
Date: March 30, 2020 08:04AM

From what Ken said about rod length tolerance variations being off as much as .010", this would explain the variation as well as anything. The inability of your engine to wind past 6000 rpm is easily explained by lifter pump up, as that rpm is in the range were it usually occurs. Try less lash, maybe 1/4 turns from zero.
Lastly, if your air fuel ratio reading was anywhere near 12.1, it will not have a nose dive in power. You cannot look at the exhaust pipe headers and automatically conclude that the engine is way too rich!
Finally, heck of a job on the S.S. tube bending and plumbing, it looks really nice!!

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

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: Crank center line shifted?
Posted by: Willt65 ()
Date: March 30, 2020 09:35AM

Your comment on the lifters pumping up is interesting, I think I went 3/4 - 1 turn from zero lash.
Do you have any experience with Rhoads lifters? They are a different animal to adjust from what I have read, if my cam checks out ok, Ill probably get a set of them. Thanks for the comment on the SS tubing, it's a challenge to get right and I love doing it!


63turbo Wrote:
-------------------------------------------------------
> From what Ken said about rod length tolerance variations being off as much as .010", this would explain the variation as well as anything. The inability of your engine to wind past 6000 rpm is easily explained by lifter pump up, as that rpm is in the range were it usually occurs. Try less lash, maybe 1/4 turns from zero.
> Lastly, if your air fuel ratio reading was anywhere near 12.1, it will not have a nose dive in power. You cannot look at the exhaust pipe headers and automatically conclude that the engine is way too rich!
> Finally, heck of a job on the S.S. tube bending and plumbing, it looks really nice!!


Will Teeter
Flintstone, MD
65 Corsa project
66 Monza parts car
49 Chevy 5 window project
08 Chevy 2500
13 Honda Odyssey
07 Honda 919
04 Honda Rancher
05 Honda Forman
96 Honda XR400R

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Re: Crank center line shifted?
Posted by: 63turbo ()
Date: March 30, 2020 10:17AM

Willt65 Wrote:
-------------------------------------------------------
> Your comment on the lifters pumping up is interesting, I think I went 3/4 - 1 turn from zero lash.
> Do you have any experience with Rhoads lifters? They are a different animal to adjust from what I have read, if my cam checks out ok, Ill probably get a set of them. Thanks for the comment on the SS tubing, it's a challenge to get right and I love doing it!
>
>
> 63turbo Wrote:
> -------------------------------------------------------
> > From what Ken said about rod length tolerance variations being off as much as .010", this would explain the variation as well as anything. The inability of your engine to wind past 6000 rpm is easily explained by lifter pump up, as that rpm is in the range were it usually occurs. Try less lash, maybe 1/4 turns from zero.
> > Lastly, if your air fuel ratio reading was anywhere near 12.1, it will not have a nose dive in power. You cannot look at the exhaust pipe headers and automatically conclude that the engine is way too rich!
> > Finally, heck of a job on the S.S. tube bending and plumbing, it looks really nice!!

I have never used Rhoad's lifters on any of my engines, but I've heard other engines that did... they are so god awful noisy, that for me personally, whatever benefit is provided by wasnt worth it because of the noise. The other thing is the main benefit of those lifters is to make a radical cam more street friendly at low rpm, not to make it necessarily work better at high rpm.
A much better way to get a hotter cam to work better on the street is to run the compression ratio higher, and get both the ignition timing better, and the cam timing better. Straight up probably isnt right for that cam!!

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

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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