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Turbo 140 cam selection.? hot smiley
Posted by: toms73novass ()
Date: November 06, 2018 12:37PM

I am building a set of modified 140 heads for boost and will be doing 4 blow through carbs like Dave Binnie. Forged Pistons and all the goodies.

The one item that I have not settled on yet is the cam.

I think I have read every post on turbo cam selection and it seems that the 304 cam or the TB20 seem to be the cams most recommended.

I do have a 304 cam in my stash, but have not committed to it yet.

I would like to hear from those that have experimented with turbo cams and what you like the best, particularly if you have experience with the TB20/304/???

Thanks

-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

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Re: Turbo 140 cam selection.? hot smiley
Posted by: BobV66Vair ()
Date: November 06, 2018 01:05PM

Talk to Binnie. He will have the most experience and has probably tried many cam's.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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Re: Turbo 140 cam selection.? hot smiley
Posted by: thewolfe ()
Date: November 06, 2018 02:21PM

Sedman would also be a good guy to ask if you can get a hold of him.

Nate Wolfe
Portland OR
65 Corsa 180

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Re: Turbo 140 cam selection.? hot smiley
Posted by: toms73novass ()
Date: November 06, 2018 03:46PM

BobV66Vair Wrote:
-------------------------------------------------------
> Talk to Binnie. He will have the most experience
> and has probably tried many cam's.


He is using a 304 in his 140 turbo..

-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

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Re: Turbo 140 cam selection.? hot smiley
Posted by: toms73novass ()
Date: November 06, 2018 03:59PM

thewolfe Wrote:
-------------------------------------------------------
> Sedman would also be a good guy to ask if you can
> get a hold of him.


Waiting on reply from Ray....

-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

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Re: Turbo 140 cam selection.? hot smiley
Posted by: Max Roeder ()
Date: November 06, 2018 04:22PM

I believe you need to identify what performance characteristics you are looking for. What are you going to do with the engine and what is needed? Matching the cam specs with the specific turbo(s) performance curves will be a questions to be answered. LSA, (lobe separation angle) controls overlap of intake to exhaust. With a turbo with smaller A/R's low end torque will probably be your sweet spot but top end will suffer. A ball bearing turbo can provide lower back pressure if the exhaust system doesn't choke off the escaping gases. Closer LSA and too much back pressure will be detrimental to performance across the spectrum. So have some answers available for the cam experts when they ask you about what your intent is.

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Re: Turbo 140 cam selection.? hot smiley
Posted by: jjohnsonjo ()
Date: November 06, 2018 06:55PM

I like my 304, but I believe Steve G moved away from them. He is a great source for turbo help. See what he says.

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

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Re: Turbo 140 cam selection.? hot smiley
Posted by: 63turbo ()
Date: November 06, 2018 07:11PM

Here are the cams I have used: stock 1963 Spyder cam, NOS 62-66 Turbo cam (304?) Otto TB-10, and the American-Pi version of a Otto TB-20. The engine,
turbo, and induction were all different with each though.


ratings: the stock 63 cam is kind of a dog cam at low rpm, it did well when
the boost came up but was definitely the kind of cam that needed a lot of timing to run well... I rate this the worst of all. The engine at the time
had 6.5:1 compression, stock distributor with Safegard and I ran it both
with a yh and weber. I ended up running this with 38(!) degrees of timing,
which did make it a lot less of a dog that way.

NOS turbo cam: much better all around power band than the 63. -this time
the heads had all the neat porting tricks and the compression had been raised
to 8:2:1, I ran this one with the stock distributor with the Safegard and stock timing, and Weber, same trick Ray Sedman heads. This cam and the other
2 are run with the same heads

TB-10... this one was run with my current F-flow/B-flow with Weber, and a 95 distributor initially, graduating to distributorless later, and then efi.
Overall this had a fairly wide powerband, probably more than the NOS turbo
cam. I noticed that at high boost and rpms this one seemed to feel like
there was a point where it felt like the brakes were being applied a little
and at least on my engine and how I had it timed had a tendency to run a bit
rough at low rpms and light loads. I rate this cam better than the other
2 stock cams, although I thought the grind was a bit "noisy"... this was probably among the first run of the "schnieder" grind of this cam, and probably
are not like that now.

American pi version of the Otto TB-20... I. LOVE. THIS. CAM!!! This sucker ROCKS!
the powerband for this cam is so cool- the engine is very rev happy, and is definitely a mid to high rpm cam... If I would have known how cool this cam was, I would have bought one of these a long time ago. There might be a very
slight loss of power below 1250-1500 compared to the "stock" TB-10, but ends
up being better than or equal to the TB-10 is when the timing and fueling are
right. I run this one with a timing curve that is very similar to kmart356 "black box" map but with a bit more retard at higher boost levels for
tuning/safety reasons, and my light load timing is a bit more.
hell of a 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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Re: Turbo 140 cam selection.? hot smiley
Posted by: steve c goodman ()
Date: November 06, 2018 07:22PM

My typical choice is still 304 cam.

best wishes, Steve
Rear Engine Spec. Inc. Golden, Colo.

1962 spyder 3.0L turbo---1965 Crown V8
1967 monza 110/4---1968 monza 110/4
1971 amante gt 110/4
CORSA/RMC/PPCC

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Re: Turbo 140 cam selection.? hot smiley
Posted by: stratovair ()
Date: November 06, 2018 08:49PM

The 304 is an excellent choice. It does run out of breath around 5500, but that is the beauty of turbocharging and strong torque figures. I think it would matter more if you were looking for a max speed record and needed longer legs. Turbo Corvair engines typically don’t need to rev as high as a N/A engine to achieve max power and torque, but I do give a nod to what Ray Sedman has been doing with roller cams. I think that would change the parameters considerably with the rollers ability for much stronger midrange power and obviously smoother cam ramp following. Every time I think of what my next project will be, I take the BT car for a burn and realize how well it performs. Best to leave it alone and build something else! Of my experience with Corvair cams and turbocharging, the 304 gets my vote.

Dave "Turbo" Binnie

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Re: Turbo 140 cam selection.? hot smiley
Posted by: toms73novass ()
Date: November 07, 2018 03:16AM

Thanks for all the feedback.

-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

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Re: Turbo 140 cam selection.? hot smiley
Posted by: jjohnsonjo ()
Date: November 07, 2018 06:10AM

toms73novass Wrote:
-------------------------------------------------------

>
> I do have a 304 cam in my stash, but have not
> committed to it yet.
>

>
> Thanks


I was looking for a NOS 304 a couple of years ago for my current build. I was warned by few guys that there are a lot of these cams that are not straight. It seems the line guys wouldn't install them and then they ended up in the service parts bin. So check yours really close. I ended up buying a new Clarks 304 repo.

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

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Re: Turbo 140 cam selection.? hot smiley
Posted by: 63turbo ()
Date: November 07, 2018 07:40AM

jjohnsonjo Wrote:
-------------------------------------------------------
> toms73novass Wrote:
> --------------------------------------------------
> -----
>
> >
> > I do have a 304 cam in my stash, but have not
> > committed to it yet.
> >
>
> >
> > Thanks
>
>
> I was looking for a NOS 304 a couple of years ago
> for my current build. I was warned by few guys
> that there are a lot of these cams that are not
> straight. It seems the line guys wouldn't install
> them and then they ended up in the service parts
> bin. So check yours really close. I ended up
> buying a new Clarks 304 repo.

+20 to that!! the main reason I swapped mine out was this very issue.
There was .007" runout on the journal's, and there is only supposed to
be a maximum of .002"

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

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: Turbo 140 cam selection.? hot smiley
Posted by: toms73novass ()
Date: November 07, 2018 08:11AM

I mine is an aftermarket 304, but will check for straightness. Thanks for the tip.

Liking Kevin's experience with Ray's Cam

-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

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Re: Turbo 140 cam selection.? hot smiley
Posted by: toms73novass ()
Date: November 11, 2018 06:30AM

Well, I'm going to give Ray's cam a try, since Kevin gave it such a glowing review.

Ray calls it his TB-25 cam. Says it is similar to the original OTTO TB-20 (not the Clarks TB-20) with a bit more grunt.

He also mentioned that the 304 cam was a good cam profile and would work well, but some power would be left on the table due to the lower valve lift.

-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

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