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140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 30, 2012 04:17PM

Hi, i am new to the sight and have had trouble finding infomation im looking for.

I have a 140 corvair in my sand rail that i need to rebuild, i did a compression test a few years back when i was redoing the frame and it was all way off (different in all cylinders). My uncle thinks the rings never sealed and im concerned with 40+ year old heads it may need new seats or guides

from reseaching on and off since then i have found that corvair builds can be quite expensive and i tend to dream big for my budget anyway...
so what would be the basics on curing the compression loss in a 140 and possibly gaining power while rebuilding it thats not too over the top $ wise?

its got a center mount carb, 60 over and reverse cam


i would appreciate any help or advice, thanks

Re: 140 rebuild guidance?...
Posted by: cnicol ()
Date: March 30, 2012 05:02PM

Hi, and welcome to the site!

I'd recommend starting with a leakdown test. This test would pinpoint just where you're losing compression. Once that's figured out and the heads are off, you can check the condition of the cylinder walls and where to go from there.

Does the engine have low blow-by and good oil pressure? If so, I'd bet the bottom end and cylinders are OK.

On the other hand, my experience with my sand-rail included enough dirt ingestion that cylinder walls got scored and compression suffered.

You won't know about guide wear until you take the heads apart but wobbly valves would certainly contribute to low and irregular compression.

Like I said, I would begin the process with a leakdown test. Do you know anyone with a leakdown tester?

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
66 Red Monza 2dr 140/4 EFI 60k
61 Seamist Jade Rampside 140 PG
65 Cypress Green Monza 140/4 4dr
65 White 4-dr 110/AC/PG (project)
64 GB -CrUnChEd (donor)
64 Monza coupe (parts)

20 Tons of parts in boxes

Re: 140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 30, 2012 05:12PM

no, i dont and not sure what that is...

and about a year or two ago i pulled the driver side head off and stopped there, does this cause an issue whit a leakdown? as i assume it does



oh, and im in Oklahoma.. anyone know someone around here that specializes in corvair engines?

Re: 140 rebuild guidance?...
Posted by: 4 carbs ()
Date: March 30, 2012 05:23PM

Rafee Corvair is in OK. www.rafeecorvair.com



John Booth
Roselle, IL.

Re: 140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 30, 2012 05:33PM

does he do machine work on the heads, or any other things i may need checked that i have no way to do


also, any tips on gaining horsepower on a reasonable budget? and what that may cost and how much power to expect?

last buggy i had was an 1835cc vw with single weber carb and a engle 110 cam..if anyone knows what can have a corvair in this powerband
im just not realy sure what to expect right now, i got the 140 in hopes of the extra power of 2 more cylinders

Re: 140 rebuild guidance?...
Posted by: 4 carbs ()
Date: March 30, 2012 06:10PM

I had my '65 140/4 complety rebuilt by Larry Claypool in Frankfort, IL. .030 over forged TRW pistons (balanced), 280 ISKY cam, heads rebuilt, new lifters. A great hwy car but lousy around town A year later I had a stock 140 cam installed. The original re-build was $6k.

Call Rafee @ 918-753-2486. He is very acommidatind.


John Booth
Roselle, IL.

Re: 140 rebuild guidance?...
Posted by: MattNall ()
Date: March 30, 2012 06:49PM

For your buggy... higher compression is the fastest / easiest way to more power.

It will have lots more power / torque than that little 1835... All the VW's that run hard, have strokers in them.


Tell us where you are located...





MODERATOR
Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
.............................PG...................................Turbo

Re: 140 rebuild guidance?...
Date: March 30, 2012 07:14PM

I'm rebuilding a 140 longblock for a Southern CA customer right now (also finishing up a 110 for a Florida customer).

Lon
www.corvairunderground.com
MARCH SALES END SATURDAY

Re: 140 rebuild guidance?...
Posted by: Ambush ()
Date: March 30, 2012 07:54PM

My buggy (140 equipped) eats 1835's for breakfast and 1915's for lunch... smoking smiley

Rich

Southern California
Addicted to dezert and dunes.. and now boats!

Re: 140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 30, 2012 08:19PM

i know they will, more displacement... my late grandpa's corvair buggy is realy what has always had me interested and that old 140 was hot! sadly it needs rebuilt too, he burned up the rings when he tried an elctric fan set up he made..only after a few trip getting excited about his extra power.. cam in it was standard rotation and more agressive then mine i believe and the heads were shaved too much so he had to relieve the pistons for the valves bc they were hitting other than that his is the same as mine

so higher compression is must..thanks matt

other things ive looked at is angle exaust, tri-port manifolds, 3brl webbers and the salih 3 5/8 cylinders...that about covers the extent of my wishes but dont know what is worth it or not. although the webbers i remember are way off the do now and the cylinders i havent found

i did read something about ray sedman makes custom cylinders but dont know the price and tried to email him from his web site several times a few years back. and starr cooke has nice stuff on ebay too


starting to look like i may just need to check on valve related head work and milling the heads...any of the other i listed worth doing?

if i sound lost, i pretty much am.. pop was the only one that knew the corvair even though he had his built in i would say the early 70's

Re: 140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 30, 2012 08:35PM

oh, yes.. i would like to build(assemble) it myself unless it seems cheap enough to have it done. my brother and i helped pop build our 1835cc vw's that was around 10 years ago. so what im wondering is what book do i need for torque and assembly instuctions? clark's is all i knew of till i decided to get online and search for other places and finally decided this would be the best place to get started in the right direction

is there a way i can tell what cam i have?

Re: 140 rebuild guidance?...
Date: March 30, 2012 09:07PM

Get 1965 Chevrolet Corvair shop manuals. They detail all the procedures and list the proper torque values for rebuilding the engine.
Get "How to Hot-Rod Corvair Engines" for a great look at the performance set-ups of the 1960s.
Look at Corvairkid.com to find the info on building a "big block" Corvair engine using VW Big Bore Cylinder/piston assembly to get more cubes.
Research about putting "slant tube" exhaust into the Corvair heads along with "angled spark plugs" and "removing the step" - All add significant gains to the 140 engines when machine work is being contemplated.




Corvanatics
to host the 2014 CorSA Int'l Convention July 21 to 25 at LeMay "America's Car Museum" - Be There!!
Dan Davis - Seattle ~ CORSA Western Director + Corvairs NW + North Cascades Corvairs + Corvanatics
1966 Corsa Turbo coupe ~ ~ 1966 140 Corsa ~ 65 Monza 140/4 'Vert Sierra Tan/Fawn (my current driver!!)
~ 1964 Monza 'Vert ~ 65 Monza 140/4 Evening Orchid w/ ivory/black int ~ 1962 Monza Wagon 102/4
1963 Rampside/Scamper ~ 1963 Red/Greenbrier ~ 1969 Ultra Van #468



Edited 1 time(s). Last edit at 03/30/2012 09:10PM by 1966-Corsa-GT-180.

Re: 140 rebuild guidance?...
Posted by: MattNall ()
Date: March 30, 2012 09:10PM

Sedman make make customs.. but most use Mahle 94 mm barrels... Ray does the machine work and supplies the parts for under $1700 last time I looked.. 3000cc!

Books?? I would Think one of Bob Helt's newer books [ "The Classic Corvair" ] is the most up to date with current techniques..

otherwise Finch's "How to keep your Corvair Alive" is an old standby..

Email Bobhelt@aol.com


You'll most likely have to wait until you've at least got the Adapter Bellhousing off..

Since you are RR'd.. most likely an Otto cam.. and the number "may" be on the end..


And you are correct... Exhaust... the #l HP limiter on Vair heads... you need to realize.... unlike Vw's.. NO NEW HEADS for Vairs... Factory only.. 1960's designs..





MODERATOR
Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
.............................PG...................................Turbo

Re: 140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 30, 2012 09:46PM

thanks guys, enjoying the feedback.

angle spark plugs? can someone explain this and the pros and cons?

and to matt, yeah i noticed no new heads even though i couldnt $ get em for my vw either at the time.

so angle/slant exhaust would be worth it if it fits the budget?
seems the big bore i realy wanted is out of the question anytime soon.. hell i may have to figure out what i want to do costs and save up for a while or try for a loan..lol

just to entertain me, has anyone tried the stroker crank?

Re: 140 rebuild guidance?...
Posted by: MattNall ()
Date: March 31, 2012 01:04AM

Roger Gaults 3.6 l 1/2 stroked Vair Engine

Relocated Sparkplugs.... when CR gets high... they must be moved...


Headwork that we are talking about will come to approx. $2k!





MODERATOR
Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
.............................PG...................................Turbo

Re: 140 rebuild guidance?...
Posted by: vairmech ()
Date: March 31, 2012 02:30AM

No matter what you do to an engine, the real power is made in the head. You can make an engine do better by adding cubic inches but when you want it to do the best it can do, it's all in the heads.

I read someone said something about angle plugs and compression earlier. Well, I have 10mm plug heads with compression around 13-1, almost alcohol range.

On the end of your cam should be some numbers, those will tel a story of what you have. If you get the engine apart and there are no numbers on the cam then you can measure the lobe height and see what the lift is and with a little guestimating you can pretty well figure what you have.

Ken Hand
CORSA Central Division Director
CORSA Treasurer
248 613 8586
[www.corvairmechanic.com]
vairmech@aol.com

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Re: 140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 31, 2012 03:06AM

just remembered an idea i had a while back
when i saw clarks new full fin cylinders, i started wondering if you could take them to .125 over with peace of mind? bc i noticed they are thicker and they said that one bored 60over is stock wall thickness

just to make note, reliablity is first for me then hp.. want it to last atleast a 10+ years or so


p.s. i remember visiting most of the sites like corvairkid ect, i will be looking over them again and refresh myself

my uncle and bro have pinto's now, uncle 2.0 and bro 2.3... any idea where i would compair in performance...bro's 2.3 was out of a guys stock car and had head work cam and stroked, but the guy swaped out his stroker crank b4 he parted with it.. uncles buggy its front end just floats up climbing hills, hope i can dodge this issue with higher gears and lighter engine... dont get me wrong i like to stant on rears but i like to be the judge of when with my left foot

Re: 140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 31, 2012 03:24AM

3.0 corvair tri-port and angle/slant exhaust is still what i want, but on the other hand i want to just drive the damn thing...
reverse rotation is nessasary with the trans i am using 091vw bus aka 6 rib bus rear suspension too. wheelbase is 91" or 87" and a king/link pin front end

What Net HP Can I Expect With It 60 over As Is, Just Valve Job, Mill Heads for 10:1 compression and rebuilt?

what hp would the 3.0 i listed be with same 10:1 comp?

and est. price of each build?

Re: 140 rebuild guidance?...
Posted by: PlumWild ()
Date: March 31, 2012 03:33AM

I mentioned i was from OKLAHOMA a few posts earlier

Re: 140 rebuild guidance?...
Posted by: MattNall ()
Date: March 31, 2012 03:33AM

PW.. you are asking a lot... too many Variances... affect cost..

And forget HP.... in buggies it's the combination..not just the engine..

Sounds like you are in SoCal? Going to Run Glamis? Ocotilla?





MODERATOR
Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
.............................PG...................................Turbo

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